Day: 08/19/2015

Tumours and Birthmarks on the Scalp

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Naevus Sebaceous

  • Naevus sebaceous are birthmarks originating from the oil glands of the skin.
  • They are present at birth, initially as a faint yellowish patch that becomes raised and rough and wart-like as the child grows older. It usually appears on the scalp, but can occur on the face and neck occasionally.
  • The lesion is asymptomatic.
  • It often enlarges at puberty, and there is a very small risk of cancer developing on the birthmarks during adulthood.
  • Surgical removal is the treatment of choice.

 

 

Seborrheic Keratoses (Seborrheic Warts, Age Spots)

  • These are benign growths on the scalp or on any part of the body.
  • They appear as discrete, sharply demarcated brownish to black patches or raised flat-topped lumps of various sizes. They have a smooth or rough surface. The lesions often appear on the face, but some may occur on the scalp.
  • They usually occur in older adults and are very common in persons over 50 years old.
  • These lesions are benign and not associated with any symptoms.
  • They do not need treatment but can be destroyed and removed by liquid nitrogen applications, electrosurgery or shave excision or laser surgery for cosmetic reasons or for diagnostic concerns.

Seborrhoeic keratosis

Seborrheic keratosis

 

 

Solar Keratoses (Actinic Keratosis)

  • Solar keratoses are pre-cancerous skin lesions on sun-exposed skin of the face and scalp.
  • On the scalp they occur on balding individuals where chronic sun exposure occurs . They are often seen in fair skinned individuals who have had exposure to sunlight for many years.
  • They often occur in middle-aged and older individuals. Solar keratoses present as ill-defined red scaly patches on the skin. The surface of the lesion looks and feel rough (akin to fine sandpaper).
  • The lesion is painless and not itchy.
  • If left untreated solar keratosis may develop into skin cancer. Solar keratoses must be destroyed to stop cancerous transformation. It is usually destroyed with liquid nitrogen applications or topical anticancer cream e.g. 5-fluorouracil. Patients with solar keratoses must avoid further sun exposure. Patients should avoid mid-day sun exposure and use sunscreen cream daily and should consult their doctor regularly to get treatment whenever new lesions occur.
  • A skin biopsy may be necessary to ascertain if a cancer has developed.

Actinic or solar keratoses

Actinic or solar keratoses

 

 

Angiosarcoma

  • This is a rare blood vessel cancer of the skin.
  • It usually occurs in elderly patients, and it commonly presents as single or grouped bluish-red nodules or plaques on the scalp, face or ears.
  • The lesions may occasionally be mildly tender but are often painless.
  • Early diagnosis is essential to improve the prognosis of such patients. A skin biopsy is essential to confirm the diagnosis.
  • Patients with angiosarcoma are referred to the oncologist for treatment. Localised lesions can be removed by surgery, but large lesions need radiotherapy.
  • The prognosis of angiosarcoma is poor generally.

Combating cancer

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Smoking hookah is not cool

Oral cancer frequently progresses without causing any pain or discomfort and is particularly dangerous because in its early stage, it cannot be felt by the patient. Often oral cancer is discovered when it has spread to other locations of the body. The most common cause is the chewable tobacco which is affordable and easily available at all paan, beedi shops.

Further, its popularity among the labourers and daily wage workers stems from the fact that it curbs hunger and gives a kind of well-being feeling in addition to being addictive. Hence the danger of this disease is immense.

In a 2014 interview, Dr Ashok Dhoble, Indian Dental Association General Secretary, noted that India has witnessed a steep growth in oral cancer patients because of the widespread use of cigarettes and chewable tobacco products. Roughly 30 per cent of India’s adult population – 15 years and older – uses some form of tobacco, according to “Tobacco use in India: An evil with many faces,” a report compiled by the American Cancer Society under the India Cancer Initiative. “Many faces” refers to the various types of smoked and smokeless tobacco products consumed in India, which include beedis, cigarettes, chillum, hookah, chutta, khaini, gutkha, paan with tobacco and paan masala.

Steps taken to curb the use of tobacco products are definitely in the right direction. But further efforts are required, not just in the obvious area of addressing addiction in tobacco products, but in creating employment opportunities for those currently working in this industry.

In India, the highest incidence of oral cancer is in the region of the tongue, followed by lips and then the salivary glands. Oral lesions can be benign or malignant and the confirmatory test is biopsy from the site. Non-invasive tests are also available to remove the doubt from a suspicious looking lesion with the dentists in the form of dyes which have reasonable accuracy to exclude the disease.

Oral cancer starts typically as a non-healing ulcer or a white or red patch in the mouth. The warning signs include change of colour, burning sensation, limited mouth opening, presence of swelling or nodules, inability to swallow, and thickening of the oral mucosa.

A regular check-up by a dental surgeon is the best way to monitor your oral health. However, self-diagnosis is also useful and can be done by examining your mouth in good daylight. Any non-healing ulcer of more than three months duration must ring the warning bell and immediately seen by a dental surgeon.

Hookah is the most common form of tobacco smoking in villages because it is cheap and generally you find hookah in village panchayats where it is passed from one person to another and another. Unfortunately, this habit is fast picking up in modern bars where hookahs are placed.

Between the smoking tobacco’s, beedis are most harmful, followed by hookah and cigarettes. However there is no doubt that they are all bad. The severity may differ.

It is also the type of tobacco used in the hookah which is most important. In India, of the total tobacco users, 48 per cent are using chewable tobacco in the form of gutkha, khaini, or zarda and 42 per cent are on smoking tobaccos with 38 per cent on beedis and 14 per cent on cigarette smoking.

As government bodies’ move toward curbing the use of tobacco products, those who use them should be constantly mindful of the dangers present. A dental visit is a good first step, as the dentist is most skilled in identifying even the most subtle signs of trouble.

Almost ‘fully-formed’ brain grown in lab for first time .

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© Amir Cohen
An almost fully-formed human brain has been grown in a lab for the very first time, in a breakthrough that could lead to a better understanding of neurological diseases such as Alzheimer’s. The brain is comparable to that of a five-week-old fetus.

About the size of a pencil eraser, the brain was created by a research team at Ohio State University, Columbus. Their work was presented at the Military Health System Research Symposium in Fort Lauderdale, Florida, on Tuesday.

The brain was engineered from human skin cells, and is the most complete human brain ever to be created in a laboratory.

The creation process involved converting the skin cells into pluripotent cells. That is, stem cells that can be programmed to become any tissue in the body. These were then put in an environment which persuaded them to grow into different components of the brain and central nervous system.

© news.osu.edu

“We provide the best possible environment and conditions that replicate what’s going on in utero to support the brain,” professor of biological chemistry and pharmacology Rene Anand, who presented his team’s work at the symposium, said in a statement.

The team claims to have reproduced 99 percent of a fetal brain’s diverse cell types and genes.

“It not only looks like the developing brain, its diverse cell types express nearly all genes like a brain,” Anand said.

Along with all major regions of the brain and multiple cell types, the model also boasts a spinal cord, signaling circuitry, and even a retina.

According to Anand, the presence of such areas has the potential to revolutionize the study of autism as well as developmental and neurological diseases such as Alzheimer’s and Parkinson’s.

“We’ve struggled for a long time trying to solve complex brain disease problems that cause tremendous pain and suffering. The power of this brain model bodes very well for human health because it gives us better and more relevant options to test and develop therapeutics other than rodents,” Anand said.

He went on to stress that the brain is not conscious, meaning there were no ethical dilemmas involved in its creation.

“We don’t have any sensory stimuli entering the brain. This brain is not thinking in any way,” said Anand.

It took about 15 weeks to develop the brain to the maturity of a five-week-old fetus.

“If we let it go to 16 or 20 weeks, that might complete it, filling in that one percent of missing genes,” Anand said.“We don’t know yet.”

NASA Admits To Chemtrails As They Propose Spraying Stratospheric Aerosols Into Earths Atmosphere

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It’s really amazing how many people are waking up to the fact that “chemtrails” are different from “con-trails.” What was once considered a conspiracy to many is now a fact, chemicals are constantly sprayed into our atmosphere and have been for quite some time now. Not long ago, NASA personnel gave a lecture (that was also streamed live) at their Jet Propulsion Laboratory at the California Institute of Technology.

It was a series of talks by scientists and engineers exploring the topic of Geoengineering and Climate Intervention. (1) Some of you might be thinking, “Geoengineering, what is that?” Geoengineering encompasses strategies to combat and reduce the effects of global warming and climate change. It’s the deliberate and large-scale intervention in the Earth’s climatic system, and one of these methods, as illustrated in the lecture, is called Solar Radiation Management (SRM) by spraying stratospheric aerosols into the atmosphere. (1) The lecture outlines how SRM would require the equivalent of airplanes spraying aerosols into our atmosphere for decades. You can see this at approximately the 32 minute mark. It seems it’s already happening. These programs are also considering spraying Aluminum into the atmosphere (if not already doing it). “There might be some good reasons to think about aluminum.

Aluminum has four times the volumetric rate for small particles as does sulphur. That means you have roughly 16 times less the coagulation rate, and that’s the thing that really drives removal.” – David Keith, Canadian Environmental Scientists, Professor of Applied Physics at Gordon McKay, Professor of Public policy, Harvard University, President of Carbon Engineering. (2) The idea of spraying aluminum into our atmosphere goes way back, patents exist that clearly demonstrate the consideration of such materials that include the oxides of metals which have high emissivity. These include harmful substances like aluminum oxide and thorium oxide. A great patent example is one from the Hughes Aircraft Company that dates all the way back to 1990, that’s over twenty years ago. You can take a look at it here. “We do stuff in the stratosphere all the time off-course, so it’s not as though the stratosphere is absolutely pristine. But you don’t want to have people going off and doing things that involve large radioactive forgings, or programs that go on for extended periods or for that matter provide lots of reactive surfaces that could result in significant ozone destruction.” – M. Granger Morgan, Carnegie Mellon University, University and Lord Chair Professor of Engineering and Public Policy, National Academy of Sciences Member (2) Did you know that “they” do stuff in the atmosphere all the time?

Is he referring to the Department of Defense? These programs are indeed backed by agencies like the CIA and NASA, they support the National Academy of Sciences with regards to geoengineering projects, and still do till this day. (3) (4) Why are Defense Intelligence Agencies in control? Is this a national security issue? If so, that means happenings with regards to geoengineering might remain classified. Below is a visual I used from a previous article to give you a good idea about SRM. If you are a constant observer of the skies, as I am, it’s not hard to see that something is already going on. This has been voiced by various individuals from all over the world. For example, Rosalind Peterson, president and Co-Founder of the Agriculture Defense Coalition (ADC), and x United States Department of Agriculture (USDA) employee stated at a 2007 United Nations hearing on global warming that: “One of the things that’s affected by climate change is agriculture, but some of what we are seeing is man made, but man made in a different way than what you may guess. Weather modification programs, experimental ones done by private companies, the US government, are underway and there are more than 50 operations underway across the United States.

All of these impact agriculture because they change the micro-climates needed for agriculture to survive. None of these programs are done with oversight. International corporations are modifying our weather all the time, and modifying it in ways that cover thousands and thousands of square miles. Most of it is chemically altered, so what happens is that we are putting ground based chemicals that are shot into the air that change and modify our weather.” You can read more, and view that full hearing here. A former premier of British Columbia felt so strong about the issue that he sent out a letter across Canada to multiple politicians voicing his concern. You can read more about that here. Neurosurgeon Russel L. Blaylock made some noise about health concerns as a result of nanoaluminum spraying, you can read about that here. Anybody who looks out their window on a bright day and watches these trails will notice them spread out and expand until the sky is covered with them. Contrails don’t do that.

There is plenty of evidence to suggest that these geonengineering techniques have already begun, and were initiated a long time ago. As far as global warming goes, that’s another controversial topic. There is no doubt climate change is occurring, but why and how is still not well understood. Is ‘global warming’ just a justification for geoengineering? Is geoengineering a cover for alternative agendas we don’t know about? These are important questions. No doubt that human activity has played a large role in the destruction of our environment. |

10 Reasons Why People Feel Lost in Life – Purpose Fairy

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“If you feel lost, disappointed, hesitant, or weak, return to yourself, to who you are, here and now and when you get there, you will discover yourself, like a lotus flower in full bloom, even in a muddy pond, beautiful and strong.” ~ Masaru Emoto

10 Reasons Why People Feel Lost in Life

Why is it that so many people feel lost in life, not knowing who they are, where they are going, and whether there is any purpose or meaning in their lives? Have you ever asked yourself any of these questions? I have. And that’s why I decided to write this blog post, in the hope that it will bring some clarity to people’s lives and help them find their way back – back to themselves, back to their hearts and back to their life’s path.

Here are 10 Reasons Why People Feel Lost in Life:

1. They have lost the connection with their own heart and Soul.

One of the many reasons why people feel lost in life is because they have disconnected from their own hearts and Souls. They pay too much attention to their rational minds, and to what everyone else has to say, and now they can no longer hear the voices of their hearts, nor can they connect to the wisdom of their Souls.

“It is only when we silent the blaring sounds of our daily existence that we can finally hear the whispers of truth that life reveals to us, as it stands knocking on the doorsteps of our hearts.” ~ K.T. Jong

2. They live their lives based on what other people believe to be right.

Another reason why people feel lost in life is because they live their lives based on what other people believe to be right for them, based on what other people think to be true. They craft their lives based on the thoughts, beliefs and ideas that were handed down to them from a very young age by their parents, family members, teachers, friends, society, and every single person with whom they interacted. And because they never took the time to question the authenticity of those beliefs, and whether they had anything to do with who they themselves are, they continued to build, craft and shape their lives based on what other people believe to be right.

“Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it.” ~ Buddha

3. They value the opinions of others more than their own.

Even though they have a very wise and trusted counselor within themselves – their heart and Soul, they don’t seem to trust themselves. They constantly seek advice from others, and the opinions of those around them always seem to be more valuable and more important than their own.

“Your time is limited, so don’t waste it living someone else’s life. Don’t be trapped by dogma – which is living with the results of other people’s thinking. Don’t let the noise of others’ opinions drown out your own inner voice. And most important, have the courage to follow your heart and intuition. They somehow already know what you truly want to become. Everything else is secondary.” ~ Steve Jobs

4. They are ruled by fear.

Their hearts are closed and fear seems to govern every area of their lives. Fear seems to be present in their minds, in their hearts, in their homes, in the work they do, in the decisions they make, in the relationships they have and in everything they do. They live in a permanent state of fear, and since love is no longer welcomed, they feel lost, disoriented, disconnected and very unhappy.

“There are two basic motivating forces: fear and love. When we are afraid, we pull back from life. When we are in love, we open to all that life has to offer with passion, excitement, and acceptance. We need to learn to love ourselves first, in all our glory and our imperfections. If we cannot love ourselves, we cannot fully open to our ability to love others or our potential to create. Evolution and all hopes for a better world rest in the fearlessness and open-hearted vision of people who embrace life.” ~ John Lennon

5. They have a distorted sense of self.

People who feel lost in life tend to have a distorted sense of self. They no longer see their beauty, their light and their perfection, and they can no longer accept this truth – that who they are is enough! Their vision of reality seems to be darkened and distorted. And all they seem to “see” is how little, unworthy and insignificant they are, and how nothing they do is good enough.

“Resolve to be thyself; and know that he who finds himself, loses his misery.” ~ Matthew Arnold

6. They surround themselves with people who drag them down.

Spending too much time with the wrong crowd is another reason why so many people feel lost in life. When you surround yourself with people who drag you down, people who are constantly whining, blaming, criticizing, gossiping and complaining about everything and everyone, poisoning your mind, your heart and your life with their fears, doubts and negativity, you will eventually get derailed from your life path, and that will cause you to feel lost. 

“People tend to be generous when sharing their nonsense, fear, and ignorance. And while they seem quite eager to feed you their negativity, please remember that sometimes the diet we need to be on is a spiritual and emotional one. Be cautious with what you feed your mind and soul. Fuel yourself with positivity and let that fuel propel you into positive action.” ~ Steve Maraboli

7. They believe every toxic thought that runs through their minds. 

Eckhart Tolle said it so beautifully: “The mind is a superb instrument if used rightly. Used wrongly, however, it becomes very destructive. To put it more accurately, it is not so much that you use your mind wrongly—you usually don’t use it at all. It uses you. All the things that truly matter — beauty, love, creativity, joy, inner peace — arise from beyond the mind…” When you believe every toxic thought that runs through your mind, and when you insist on building your sense of self and your entire life based on those thoughts, you can’t help but feel lost. 

8. They believe logic is more important than imagination.

People who suffer from a lack of imagination feel compelled to rationalize everything that happens to them. Constantly seeking to give logical explanations, to themselves and to others, for why they can’t move on with their lives, for why they aren’t as happy as they would like to be, and for why their present and future lives will be nothing but a replica of their past. And that’s just another reason why people feel lost in life. 

“Anyone who lives within their means suffers from a lack of imagination.” ~ Oscar Wilde

9. They are stuck in the past.

They are very attached to their past and everything that happened in it. And they just can’t seem to find a way to free themselves from it, not do they want to. 

“People have a hard time letting go of their suffering. Out of a fear of the unknown, they prefer suffering that is familiar.” ~ Thich Nhat Hanh

10. They try to control everything.

They can’t seem to understand that life has a natural flow that is always working with them, and so, they choose to push against it by trying to control everything and everyone. As a result, they get imbalanced, they disconnect from their own heart and soul, and they start to feel more and more lost with every day that passes.

“You who cannot even control yourself should hardly aspire to control the universe.” ~ ACIM

We all get lost from time to time, and even though you might not always like it, you have to understand that it’s all part of this adventure called life. It’s all part of your journey. If you immerse yourself fully into every experience and every interaction life sends your way, no matter if good or bad, you will have so much to gain. And when the time comes for you to return “Home”, you will never return empty handed, but with   many valuable lessons, great insights and a lot of wisdom. So always remember, “It is good to feel lost… because it proves you have a navigational sense of where ‘Home’ is. You know that a place that feels like being found exists. And maybe your current location isn’t that place but, Hallelujah, that unsettled, uneasy feeling of lost-ness just brought you closer to it.”

New algorithm for estimating body mass of extinct quadrupedal mammals

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mammoth
Restoration of a steppe mammoth. Credit: Kurzon/Wikipedia, CC BY-SA 3.0

A pair of researchers, one with the University of Manchester, the other with the University of Salford, both in the U.K., has developed a new computer algorithm for estimating the body mass of extinct quadrupedal mammals. In their paper published in Royal Society Open Science, Charlotte Brassey and James Gardiner describe how they came up with the new algorithm and the ways that they believe it can be used to improve estimates of body mass of extinct creatures.

Ever since humans discovered that there were creatures roaming the earth that had gone extinct, efforts have been made to try to imagine what they must have looked like. Skeletons have been reassembled and then estimates on body shape and mass were made based on how modern animals are put together—but such efforts have been deemed too open to interpretation, which likely meant that researchers were simply guessing. In an attempt to improve the accuracy, other researchers developed 3D computer models and simulations, but have had to acknowledge that there was still a lot of guesswork involved.

Now, in an attempt to remove some of that guesswork, Brassey and Gardiner have developed a that takes advantage of the best aspects of both prior methods. Their algorithm allows for the creation of what they call “alpha-shapes” where objects meant to mimic actual body parts, are “shrink-wrapped” around a reconstructed virtual skeleton created from the actual bones of a real specimen. The algorithm also allows for fine-tuning the shrink wrapping process from very fine, to quite coarse—on an individual specimen. Once the rendering is done, the algorithm calculates the original of the creature by using an average of the body mass of 14 modern animals.

Brassey and Gardiner have tested their on the remains of a found wooly mammoth and a giant sloth—the first was calculated to be 3.6 metric tons, the second 3.7. They note that the reconstruction of the skeleton has a big impact on the final result, which means that in order to get an accurate body mass estimate, researchers must first put the skeleton together in the way that nature intended.

More information: An advanced shape-fitting algorithm applied to quadrupedal mammals: improving volumetric mass estimates, Published 19 August 2015.DOI: 10.1098/rsos.150302

Abstract
Body mass is a fundamental physical property of an individual and has enormous bearing upon ecology and physiology. Generating reliable estimates for body mass is therefore a necessary step in many palaeontological studies. Whilst early reconstructions of mass in extinct species relied upon isolated skeletal elements, volumetric techniques are increasingly applied to fossils when skeletal completeness allows. We apply a new ‘alpha shapes’ (α-shapes) algorithm to volumetric mass estimation in quadrupedal mammals. α-shapes are defined by: (i) the underlying skeletal structure to which they are fitted; and (ii) the value α, determining the refinement of fit. For a given skeleton, a range of α-shapes may be fitted around the individual, spanning from very coarse to very fine. We fit α-shapes to three-dimensional models of extant mammals and calculate volumes, which are regressed against mass to generate predictive equations. Our optimal model is characterized by a high correlation coefficient and mean square error (r2=0.975, m.s.e.=0.025). When applied to the woolly mammoth (Mammuthus primigenius) and giant ground sloth (Megatherium americanum), we reconstruct masses of 3635 and 3706 kg, respectively. We consider α-shapes an improvement upon previous techniques as resulting volumes are less sensitive to uncertainties in skeletal reconstructions, and do not require manual separation of body segments from skeletons.

Does E-Cigarette Use Lead to Combustible Tobacco Product Use in Adolescents?

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Among ninth graders who did not use combustible tobacco products, e-cigarette use was associated with increased risks for smoking combustible cigarettes, cigars, and hookah during the subsequent year.

 An estimated 16% of U.S. tenth graders have tried e-cigarettes, of whom 43% have never smoked combustible cigarettes. To determine whether use of e-cigarettes during adolescence increases the likelihood of subsequently using combustible tobacco products (cigarette, cigar, or hookah), investigators analyzed data from a longitudinal study of high school students surveyed in the fall of ninth grade (baseline) and then 6 and 12 months later.

Of 2530 students who had never used combustible tobacco control products at baseline (mean age, 14 years; 53% female; 19% Asian, 44% Hispanic, 16% white), 222 (9%) had used e-cigarettes. At each follow-up period, e-cigarette users at baseline were more likely than nonusers to begin using any combustible tobacco product during the previous 6-month period (31% vs. 8% at 6 months; 25% vs. 9% at 12 months). Adjustment for peer smoking, impulsivity, any previous use of non-nicotine and non-tobacco substances, delinquent behavior, and smoking expectancies — but not for socioeconomic status or other psychosocial variables — attenuated but did not eliminate the significant relationship between baseline e-cigarette use and transition to using combustible cigarettes (adjusted odds ratio, 1.75), cigars (AOR, 2.96), or hookah (AOR, 2.26). Baseline use of cigarettes or hookah but not cigars was associated with e-cigarette initiation across follow-up periods in fully adjusted models.

COMMENT

This well-executed study provides strong evidence that use of e-cigarettes is prospectively associated with uptake of combustible tobacco product use among ninth graders. Although the authors controlled for numerous key variables related to both e-cigarette use and combustible tobacco product use, the possibility of unknown confounding remains. It would be interesting to know what variables were protective for the 70% of baseline e-cigarette users who did not initiate combustible tobacco product use during the following year.

 

New temperature record: Hydrogen sulfide becomes superconductive under high pressure at minus 70 degrees Celsius

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The apparatus the team led by Mikhail Eremets at the Max Planck Institute for Chemistry in Mainz uses to generate extremely high pressures, is amazingly handy. The researchers press the metal cell with Allen screws together. The high pressure thus created in the center of the cell, only diamonds resist. The gems operate like anvils that compress a sample. Credit: Thomas Hartmann

Up until now, no material has been able to conduct current with no resistance at such high temperatures: Researchers at the Max Planck Institute for Chemistry in Mainz and the Johannes Gutenberg University Mainz observed that hydrogen sulfide becomes superconductive at minus 70 degree Celsius—when the substance is placed under a pressure of 1.5 million bar. This corresponds to half of the pressure of the earth’s core. With their high pressure experiments the researchers in Mainz have thus not only set a new record for superconductivity—their findings have also highlighted a potential new way to transport current at room temperature with no loss.

For many solid-state physicists, superconductors that are suitable for use at room temperature are still a dream. Up until now, the only materials known to conduct current with no and thus no loss did so only at very low temperatures. Accordingly, special copper ceramics (cuprates) took the leading positions in terms of —the temperature at which the material loses its resistance. The record for a ceramic of this type is roughly minus 140 degrees Celsius at normal air pressure and minus 109 degrees Celsius at . In the ceramics, a special, unconventional form of superconductivity occurs. For conventional superconductivity, temperatures of at least minus 234 degrees Celsius have so far been necessary.

A team led by Mikhael Eremets, head of a working group at the Max Planck Institute for Chemistry, working in collaboration with the researchers at Johannes Gutenberg University Mainz has now observed conventional superconductivity at minus 70 degrees Celsius, in (H2S). To convert the substance, which is a gas under normal conditions, into a superconductor the scientists did however have to subject it to a pressure of 1.5 megabar (1.5 million bar), as they describe in the latest edition of the science magazine Nature.

The transition temperature of conventional superconductivity knows no limits

“With our experiments we have set a new record for the temperature at which a material becomes superconductive,” says Mikhael Eremets. His team has also been the first to prove in an experiment that there are conventional superconductors with a high transition temperature. Theoretical calculations had already predicted this for certain substances including H2S. “There is a lot of potential in looking for other materials in which conventional superconductivity occurs at ,” says the physicist. “There is theoretically no limit for the transition temperature of conventional superconductors, and our experiments give reason to hope that superconductivity can even occur at room temperature.”

The researchers generated the extremely high pressure required to make H2S superconductive at comparatively moderate negative temperatures in a special pressure chamber smaller than one cubic centimeter in size. The two diamond tips on the side, which act as anvils, are able to constantly increase the pressure that the sample is subjected to. The cell is equipped with contacts to measure the electrical resistance of the sample. In another high-pressure cell, the researchers were able to investigate the magnetic properties of a material that also change at the transition temperature.

After the researchers had filled the pressure chamber with liquid hydrogen sulfide, they increased the pressure acting on the sample gradually up to roughly two megabar and changing the temperature for each pressure level. They took measurements of both resistance and magnetization to determine the material’s transition temperature. The magnetization measurements provide very useful information, because a superconductor possesses ideal magnetic properties.

Hydrogen atoms facilitate superconductivity at high temperatures

The researchers believe that it is mainly hydrogen atoms that are responsible for hydrogen sulfide losing its electrical resistance under high pressure at relatively high temperatures: Hydrogen atoms oscillate in the lattice with the highest frequency of all elements, because hydrogen is the lightest. As the oscillations of the lattice determine the conventional superconductivity—and do this more effectively the faster the atoms oscillate—materials with high hydrogen content exhibit a relatively high transition temperature. In addition, strong bonds between the atoms increase the temperature at which a material becomes superconductive. These conditions are met in H3S, and it is precisely this compound that develops from H2S at high pressure.

Mikhael Eremets and his team are now looking for materials with even higher transition temperatures. Increasing the pressure acting on the hydrogen sulfide above 1.5 megabar is not helpful in this case. This has not only been calculated by theoretical physicists, but now also confirmed in experiments performed by the team in Mainz. At even higher temperatures the electron structure changes in such a way that the transition temperature slowly begins to drop again.

Wanted: hydrogen-rich materials with a higher transition temperature

“An obvious candidate for a high transition temperature is pure hydrogen,” says Mikhael Eremets. “It is expected that it would become superconductive at room temperature under high pressure.” His team has already begun experimenting with pure hydrogen, but the experiments are very difficult as pressures of three to four megabar are required.

“Our research into hydrogen sulfide has however shown that many hydrogen-rich materials can have a high transition temperature,” says Eremets. It may even be possible to realize a high-temperature superconductor worth the name in terms of common temperature perception without high pressure. The researchers in Mainz currently need the high pressure to convert materials that act electrically insulating like hydrogen sulfide into metals. “There may be polymers or other hydrogen-rich compounds that can be converted to metals in some other way and become superconductive at ,” says the physicist. If such materials can be found, we would finally have them: superconductors that can be used for a wide range of technical applications.

Going solid-state could make batteries safer and longer-lasting

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Going solid-state could make batteries safer and longer-lasting
Illustrations show the crystal structure of a superionic conductor. The backbone of the material is a body-centred cubic-like arrangement of sulphur anions. Lithium atoms are depicted in green, sulfur atoms in yellow, PS4 tetrahedra in purple, and GeS4 tetrahedra in blue. Researchers have revealed the fundamental relationship between anion packing and ionic transport in fast lithium-conducting materials. Credit: Yan Wang

If you pry open one of today’s ubiquitous high-tech devices—whether a cellphone, a laptop, or an electric car—you’ll find that batteries take up most of the space inside. Indeed, the recent evolution of batteries has made it possible to pack ample power in small places.

But people still always want their devices to last even longer, or go further on a charge, so researchers work night and day to boost the power a given size can hold. Rare, but widely publicized, incidents of overheating or combustion in lithium-ion batteries have also highlighted the importance of safety in battery technology.

Now researchers at MIT and Samsung, and in California and Maryland, have developed a new approach to one of the three basic components of batteries, the . The new findings are based on the idea that a solid electrolyte, rather than the liquid used in today’s most common rechargeables, could greatly improve both device lifetime and safety—while providing a significant boost in the amount of power stored in a given space.

The results are reported in the journal Nature Materials in a paper by MIT postdoc Yan Wang, visiting professor of materials science and engineering Gerbrand Ceder, and five others. They describe a new approach to the development of solid-state electrolytes that could simultaneously address the greatest challenges associated with improving lithium-ion batteries, the technology now used in everything from cellphones to electric cars.

The electrolyte in such batteries—typically a liquid organic solvent whose function is to transport charged particles from one of a battery’s two electrodes to the other during charging and discharging—has been responsible for the overheating and fires that, for example, resulted in a temporary grounding of all of Boeing’s 787 Dreamliner jets, Ceder explains. Others have attempted to find a solid replacement for the , but this group is the first to show that this can be done in a formulation that fully meets the needs of battery applications.

Solid-state electrolytes could be “a real game-changer,” Ceder says, creating “almost a perfect battery, solving most of the remaining issues” in battery lifetime, safety, and cost.

Costs have already been coming down steadily, he says. But as for safety, replacing the electrolyte would be the key, Ceder adds: “All of the fires you’ve seen, with Boeing, Tesla, and others, they are all electrolyte fires. The lithium itself is not flammable in the state it’s in in these batteries. [With a solid electrolyte] there’s no safety problem—you could throw it against the wall, drive a nail through it—there’s nothing there to burn.”

The proposed solid electrolyte also holds other advantages, he says: “With a solid-state electrolyte, there’s virtually no degradation reactions left”—meaning such batteries could last through “hundreds of thousands of cycles.”

The key to making this feasible, Ceder says, was finding solid materials that could conduct ions fast enough to be useful in a battery.

“There was a view that solids cannot conduct fast enough,” he says. “That paradigm has been overthrown.”

The research team was able to analyze the factors that make for efficient ion conduction in solids, and home in on compounds that showed the right characteristics. The initial findings focused on a class of materials known as superionic lithium-ion conductors, which are compounds of lithium, germanium, phosphorus, and sulfur, but the principles derived from this research could lead to even more effective materials, the team says.

The research that led to a workable solid-state electrolyte was part of an ongoing partnership with the Korean electronics company Samsung, through the Samsung Advanced Institute of Technology in Cambridge, Massachusetts, Ceder says. That alliance also has led to important advances in the use of quantum-dot materials to create highly efficient solar cells and sodium batteries, he adds.

This solid-state electrolyte has other, unexpected side benefits: While conventional do not perform well in extreme cold, and need to be preheated at temperatures below roughly minus 20 degrees Fahrenheit, the solid-electrolyte versions can still function at those frigid temperatures, Ceder says.

The solid-state electrolyte also allows for greater power density—the amount of power that can be stored in a given amount of space. Such batteries provide a 20 to 30 percent improvement in power density—with a corresponding increase in how long a battery of a given size could power a phone, a computer, or a car.

Ambient sound may help protect your online accounts

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Ambient sound may help protect your online accounts
Block diagram of the function that computes the similarity score between two samples. The computation takes place on the phone. Credit: arXiv:1503.03790 [cs.CR]

Two-factor authentication based on ambient sound has been the focus of four researchers from the Institute of Information Security ETH Zurich. Nikolaos Karapanos, Claudio Marforio, Claudio Soriente, and Srdjan Capkun posted their work on the .arXiv server and they presented their research at the recent Usenix conference in Washington, DC.

As they see it, may be a good way to address the risk of stolen passwords but why is it not very popular? They said, “Despite the improvements introduced by software tokens, most users still prefer password-only authentication for services where 2FA is not mandatory. This is probably due to the extra burden that 2FA causes to the user, since it typically requires the user to interact with his phone.”

Fair enough. Wired‘s Klint Finley described the frustration like this: “Two-factor authentication provides much better security than a password alone, and you really should enable it everywhere you can: Gmail, Facebook, Twitter, your bank. But there is one big problem with it: it’s really annoying. Every time you want to log in to a site, you have to get your phone out, unlock it, find the authentication code, and type it in. If you type too slowly, the code changes and you’ve gotta try again. For far too many people, this is just too big of a hassle, so they leave themselves open to attack.”

The authors propose another path to protection, in the name of Sound-Proof. They said it is a two-factor authentication mechanism transparent to the user; it can be used with current phones and with major browsers without any plugin.

The process goes like this: the second authentication factor is the proximity of the user’s phone to the computer being used to log in. Sound-Proof works even if the phone is in the user’s pocket or purse, and both indoors and outdoors.

“When the user logs in,” said the researchers, “the two devices record the ambient noise via their microphones. The phone compares the two recordings, determines if the computer is located in the same environment, and ultimately decides whether the login attempt is legitimate or fraudulent.”

They implemented a prototype of Sound-Proof for both Android and iOS. Their findings: “Sound-Proof adds, on average, less than 5 seconds to a password-only login operation. This time is substantially shorter than the time overhead of 2FA mechanisms based on verification codes (roughly 25 seconds). We also report on a user study we conducted which shows that users prefer Sound-Proof over Google 2-Step Verification.”

According to the researchers, “The security of Sound-Proof stems from the attacker’s inability to guess the sound in the victim’s environment at the time of the attack.”

Nonetheless, pointed out Finley, “if someone is in the same room as you—at a coffee shop for example—and has your password, they could access your account. There’s also the possibility that if someone is watching the exact same TV or radio broadcast that you are, they might be able to spoof the request, depending on other ambient sound in the room, as well as differences in broadcast latencies. But the researchers think such targeted attacks will be uncommon. And besides, they argue, it would be far better than not using two-factor at all.”

 

Abstract
Two-factor authentication protects online accounts even if passwords are leaked. Most users, however, prefer password-only authentication. One reason why two-factor authentication is so unpopular is the extra steps that the user must complete in order to log in. Currently deployed two-factor authentication mechanisms require the user to interact with his phone to, for example, copy a verification code to the browser. Two-factor authentication schemes that eliminate user-phone interaction exist, but require additional software to be deployed.
In this paper we propose Sound-Proof, a usable and deployable two-factor authentication mechanism. Sound-Proof does not require interaction between the user and his phone. In Sound-Proof the second authentication factor is the proximity of the user’s phone to the device being used to log in. The proximity of the two devices is verified by comparing the ambient noise recorded by their microphones. Audio recording and comparison are transparent to the user, so that the user experience is similar to the one of password-only authentication. Sound-Proof can be easily deployed as it works with current phones and major browsers without plugins. We build a prototype for both Android and iOS. We provide empirical evidence that ambient noise is a robust discriminant to determine the proximity of two devices both indoors and outdoors, and even if the phone is in a pocket or purse. We conduct a user study designed to compare the perceived usability of Sound-Proof with Google 2-Step Verification. Participants ranked Sound-Proof as more usable and the majority would be willing to use Sound-Proof even for scenarios in which two-factor authentication is optional.