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  • richardmitnick 12:07 pm on April 6, 2018 Permalink | Reply
    Tags: Australia looks set to become a significant global player in the emerging quantum computing market, , Q-CTRL, Sydney teams with Silicon Valley to boost quantum computing R&D, U Sidney   

    From U Sidney via COSMOS: “Sydney teams with Silicon Valley to boost quantum computing R&D” 

    U Sidney bloc

    University of Sidney

    COSMOS

    06 April 2018
    Andrew Masterson

    1
    A collaboration between IBM and Sydney quantum researchers could pay rich dividends for Australia’s tech sector. NIGEL TREBLIN / Getty Images.

    Australia looks set to become a significant global player in the emerging quantum computing market after a Sydney-based firm was picked to collaborate with US tech giant IBM to develop the industry.

    Q-CTRL, a company established by physicists working at the University of Sydney, is one of eight start-ups chosen by IBM from a wide field of candidates.

    Researchers at the university recently reported a significant advance in tackling one of the major problems bedevilling quantum computing development – system noise.

    The fundamental basis of the field revolves around entangling quantum bits, or qubits, such that they occupy a superposition comprising two possible information states. The “bits” that define classical computing technology can only ever express one such state (0 or 1, for example), and qubits’ ability to express both simultaneously is the key advantage of a quantum system.

    However, entangled qubits are by nature extremely fragile, and entanglement can be lost (and the information encoded by them destroyed) very easily. In practical terms, a major cause of this decoherence – as the jargon has it – is the noise generated by the very system that produces it in the first place.

    In a paper published in the journal Physical Review Letters earlier this year researchers from the university’s Centre for Engineered Quantum Systems revealed a “hack” – a simple modification to coding – that resulted in an enormous improvement in robustness before decoherence kicks in.

    The scientists reported a stunning 400% increase in the amount of interference the system could stand before breaking down.

    This and related research contributed to Q-CTRL’s appeal for IBM.

    Company founder Michael Biercuk says working with the California-based corporation is a natural alliance for it.

    “Working with IBM is a logical step for Q-CTRL to develop real solutions to one of the hardest problems in quantum computing – dealing with hardware error,” he says.

    “As IBM continues to scale-up its quantum computers, we will gain direct access to the company’s most advanced devices and have an opportunity to help solve some of quantum computing’s most vexing challenges.

    “Our techniques are already validated through our ion-trapping laboratory. Working with IBM gives us a new opportunity to test these concepts on a totally different kind of quantum computing hardware.”

    The successful development of working, sustainable quantum computers is widely predicted to transform industry, research, cryptography and, indeed, in time, everyday life.

    IBM is recognised as a leading contender in the field, but it is by no means the only horse in the race. Other tech titans, including Google, Microsoft, IonQ and Rigetti, are prominent in the field.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

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  • richardmitnick 1:05 pm on November 29, 2017 Permalink | Reply
    Tags: , , U Sidney   

    From U Sidney via Science Alert: “Physicists Just Invented an Essential Component Needed For Quantum Computers” 

    U Sidney bloc

    University of Sidney

    Science Alert

    29 NOV 2017
    MIKE MCRAE

    1
    (The University of Sydney)

    They’re using a new state of matter for this.

    In 2016, the Nobel Prize in Physics went to three British scientists for their work on superconductors and superfluids, which included the explanation of a rather odd phase of matter.

    Now, for the first time, their discovery has a practical application – shrinking an electrical component to a size that will help quantum computers reach a scale that just might make them useful.

    In a collaboration with Stanford University in the US, a team of scientists from the University of Sydney and Microsoft have used the newly found phase of matter – topological insulator – in shrinking an electrical component called a circulator 1,000 times smaller.

    That’s super good news when it comes to squeezing more qubits into a small enough space.

    If you missed the fuss last year, a trio of physicists received the Nobel Prize for discovering that under certain conditions some materials could easily conduct electrons along their surface, but remain an insulator within.

    Most importantly, they discovered cases where matter transitioned between states without breaking something called symmetry, as happens when water atoms rearrange into ice or vapour.

    As we shrink electrical components down to virtually atomic scales, the way electrons move in different dimensions becomes increasingly important.

    Enter the qubit – a chunky piece of electronics that uses the probabilities of an unmeasured bit of matter to perform calculations classical computers can’t hope to match.

    We can make qubits in a variety of ways, and are getting pretty good at stringing them together in ever larger numbers.

    But shrinking qubits to sizes small enough that we can shove hundreds of thousands into a small-enough space is a challenge.

    “Even if we had millions of qubits today, it is not clear that we have the classical technology to control them,” says David Reilly, a physicist at the University of Sydney and Director of Microsoft Station Q.

    “Realising a scaled-up quantum computer will require the invention of new devices and techniques at the quantum-classical interface.”

    One such device is called a circulator, which is kind-of like a roundabout for electrical signals, ensuring information heads in one direction only.

    Until now, the smallest versions of this hardware could be held in the palm of your hand.

    This is now set to change as scientists have shown a magnetised wafer made of a particular topological insulator could do the job, and be made 1,000 times smaller than existing components.

    “Such compact circulators could be implemented in a variety of quantum hardware platforms, irrespective of the particular quantum system used,” says the study’s lead author, Alice Mahoney.

    In many respects, we’re still at the pre-vacuum-tube and magnetic tape phase of quantum computers – they’re more promise than practical.

    But if we keep seeing advances like this, it won’t be long before we’ll be bringing you news of quantum computers cracking problems which leave our best supercomputers gasping.

    This research was published in Nature Communications.

    See the full article here .

    Please help promote STEM in your local schools.

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    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
  • richardmitnick 4:01 pm on November 13, 2017 Permalink | Reply
    Tags: Electrons can ‘tunnel’ through barriers in aqueous solutions away from the electrodes neutralising ions of impurities in that water, , Quantum Tunneling, Quantum tunnelling in electrolysis was proposed in 1931 by Ronald Gurney (a student of Australian Nobel laureate William Bragg) but has not been confirmed until now, Researchers at the University of Sydney have applied quantum techniques to understanding the electrolysis of water, U Sidney   

    From U Sidney: “Tomb-raided quantum theory opens way to improved biosensing” 

    U Sidney bloc

    University of Sidney

    1
    Ain’t no mountain high enough: electrons can tunnel through barriers in certain circumstances.
    Richard Kail/Science Photo Library

    8 November 2017

    Marcus Strom
    Phone +61 2 8627 6433
    Mobile +61 423 982 485
    marcus.strom@sydney.edu.au

    Tunnelling electrons should speed up medical sensing technology.

    Hydrogen-based solar energy storage and biosensing techniques could be dramatically improved after University of Sydney researchers show the validity of theory first proposed in 1931.

    2
    Humans have known of electrolysis for more than 200 years. It was formally described by Faraday in 1833. Image from Robert Amory’s “A treatise on electrolysis and its applications to therapeutical and surgical treatment in disease” (1886). Source: Flickr Commons

    Researchers at the University of Sydney have applied quantum techniques to understanding the electrolysis of water, which is the application of an electric current to H2O to produce the constituent elements hydrogen and oxygen.

    They found that electrons can ‘tunnel’ through barriers in aqueous solutions away from the electrodes, neutralising ions of impurities in that water. This can be detected in changes in current, which has applications for biosensing, the detection of biological elements in solution.

    This neutralisation of ions in solution is a different idea to that currently believed, where the neutralisation only happens at the electrode surface.

    Quantum tunnelling in electrolysis was proposed in 1931 by Ronald Gurney (a student of Australian Nobel laureate William Bragg) but has not been confirmed until now.

    The idea that tunnelling through water really does occur was suspected from recent work on the scanning tunnelling microscope, the invention of which was awarded the Nobel prize for physics in 1986.

    Professor David McKenzie from the School of Physics said: “This lays the basis for new and faster methods to detect biomedical impurities in water, with potentially important implications for biosensing techniques.”

    Professor McKenzie also said: “A better understanding of electrolysis is becoming more important for applications in alternative energies in what is sometimes called the ‘hydrogen economy’.”

    Without storage methods, solar energy only works when the sun is shining.

    To produce energy at other times, one method is to use electricity from solar cells to electrolyse water, producing hydrogen gas which can then be stored and burned later to produce energy when needed.

    The tunnelling effect refers to the quantum mechanical process where a particle moves through a barrier that in classical physical theory should not occur.

    Electrons are able to ‘tunnel’ in biological and chemical systems in a non-trivial manner that has implications for photosynthesis and other biological processes. It occurs through barriers that are just a few nanometres thick, a billionth of a metre.

    The research was conducted by Professor McKenzie and his PhD student, Enyi Guo and was published on Wednesday in the Proceedings of the Royal Society.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
    • tubeist- dan 12:13 pm on November 14, 2017 Permalink | Reply

      cold fusion then?

      Like

    • richardmitnick 12:24 pm on November 14, 2017 Permalink | Reply

      Your question is beyond my knowledge.

      Like

      • tubeist- dan 12:39 pm on November 14, 2017 Permalink | Reply

        The (original) claim of ‘cold fusion’ involved purported deuteron tunneling, thence fusion, in an electrolytic context. Clearly a deuteron is far more massive than an electron, and will require a shorter/thinner barrier to tunnel, but the outcome here is suggestive.

        I’ll see if the cold fusion crowd takes up the question; it must be ringing their bells.

        Like

  • richardmitnick 8:22 pm on October 16, 2017 Permalink | Reply
    Tags: , , , , , , , U Sidney   

    From U Sidney: “Gravitational waves world-first discovery Down Under” 

    U Sidney bloc

    University of Sidney

    17 October 2017

    Sydney confirms radio emission from gravitational wave event.

    A Sydney team was the first in the world to confirm radio waves from the latest gravitational waves event, resulting from a spectacular neutron star merger that has produced light and radio waves as well as gravitational waves.

    How the discovery unfolded in Sydney.

    An Australian group was the first in the world to confirm the radio emission from a gravitational wave event, discovered by collaborators in the United States being announced today.

    The discovery of gravitational waves in 2015 was awarded the Nobel Prize for physics this year. The discovery of these ripples in space-time, produced by massive, accelerating bodies, like orbiting black holes (which cannot be seen directly) or neutron stars, confirms a prediction made by Albert Einstein in 1916.

    Now, a group led by Associate Professor Tara Murphy, from the University of Sydney and the Centre of Excellence for All-Sky Astrophysics (CAASTRO), has confirmed radio-wave emission from a gravitational wave event discovered on 17 August this year.

    The results are included in a Science paper published today with co-author institutions including the California Institute of Technology (Caltech) and Oxford University; simultaneously teams from the international science community are publishing related research in other leading journals, demonstrating the second epoch in gravitational waves discovery.

    Scientists representing LIGO-Virgo, and some 70 observatories today reveal the gravitational waves discovery – the first to produce light and radio waves, not just gravitational waves.

    The explosion, produced by a pair of neutron stars merging, took place in galaxy NGC 4993, about 130 million light-years away. The first follow-up detection was optical, about 11 hours after the event, and was detected by a number of groups worldwide. X-ray emissions were detected nine days later and radiowaves after 15 days.

    University of Sydney Associate Professor Tara Murphy, who leads the radio astronomy follow-up in Australia, said she was in the United States with colleague David Kaplan when they saw the gravitational wave announcement come through on the private email list of the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO).


    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation


    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger-Zib

    ESA/eLISA the future of gravitational wave research

    1
    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    “We immediately rang our team in Australia and told them to get onto the CSIRO telescope as soon as possible, then started planning our observations,” she said.

    CSIRO/Parkes Observatory, located 20 kilometres north of the town of Parkes, New South Wales, Australia

    “We were lucky in a sense in that it was perfect timing but you have to be at the top of your game to play in this space. It is intense, time-critical science.”

    PhD candidate Dougal Dobie spent hours observing on the telescope. More details in today’s piece by Associate Professor Murphy in The Conversation.

    The team used the CSIRO’s Australia Telescope Compact Array to monitor the gravitational wave event for more than 40 hours over several weeks. Dr Douglas Bock, Director of CSIRO’s Astronomy & Space Science team, said this extraordinary detection by an Australian team, using Australian facilities, made a significant contribution to the global discovery.

    “Running a national facility involves providing researchers with access – fast – so they can monitor unexpected astronomical events of extraordinary scientific interest,” Dr Bock said.

    The ARC Centre of Excellence for Gravitational Waves (OzGrav) director Professor Matthew Bailes said: “Never before have we seen where in the Universe gravitational waves came from; the subsequent avalanche of science was virtually unparalleled in modern astrophysics.”

    University of Sydney Vice-Chancellor and Principal Dr Michael Spence said: “This international discovery, with Sydney playing an integral role, demonstrates that the best science and modern innovation is intrinsically a collaborative effort.

    “What better a way to confirm that Einstein’s theory of relativity was correct, gain insights into massive bodies like black holes and, with this knowledge, start to re-think our understanding of the Universe,” Dr Spence concluded.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
  • richardmitnick 5:39 am on September 7, 2017 Permalink | Reply
    Tags: , Majorana fermions as the basis for quantum computers, , Quantum detectives in the hunt for the world's first quantum computer, Station Q Sydney, Topological quantum computers, U Sidney   

    From U Sidney via phys.org: “Quantum detectives in the hunt for the world’s first quantum computer” 

    U Sidney bloc

    University of Sidney

    phys.org

    September 7, 2017

    2
    Launch of the University of Sydney partnership with Microsoft.Front row: Ph.D. candidate Alice Mahoney with Microsoft’s David Pritchard. Back row (R-L): Station Q Sydney director Professor David Reilly; Microsoft’s Douglas Carmean; Station Q Sydney senior research scientist Dr. Maja Cassidy; University of Sydney Chancellor Belinda Hutchinson, postdoctoral researcher Dr. John Hornibrook and University of Sydney Vice-Chancellor Dr. Michael Spence. Credit: Jayne Ion/University of Sydney

    Scientists at the University of Sydney are entering a new phase of development to scale up the next generation of quantum-engineered devices.

    These devices will form the heart of the first practical topological quantum computers.

    A study released today in Nature Communications confirms one of the prerequisites for building these devices.

    An author of that paper, Dr Maja Cassidy, said: “Here at Station Q Sydney we are building the next generation of devices that will use quasiparticles known as Majorana fermions as the basis for quantum computers.”

    Dr Cassidy said the $150 million Sydney Nanoscience Hub provides a world-class environment in which to build the next generation of devices.

    Microsoft’s Station Q will move scientific equipment into the Nanoscience Hub’s clean rooms – controlled environments with low levels of pollutants and steady temperatures – over the next few months as it increases capacity to develop quantum machines.

    Detective hunt

    Dr Cassidy said that building these quantum devices is a “bit like going on a detective hunt”.

    “When Majorana fermions were first shown to exist in 2012, there were many who said there could be other explanations for the findings,” she said.

    A challenge to show the findings were caused by Majoranas was put to the research team led by Professor Leo Kouwenhoven, who now leads Microsoft’s Station Q in the Netherlands.

    The paper published today meets an essential part of that challenge.

    In essence, it proves that electrons on a one-dimensional semiconducting nanowire will have a quantum spin opposite to its momentum in a finite magnetic field.

    “This information is consistent with previous reports observing Majorana fermions in these nanowires,” Dr Cassidy said.

    She said the findings are not just applicable to quantum computers but will be useful in spintronic systems, where the quantum spin and not the charge is used for information in classical systems.

    Dr Cassidy conducted the research while at the Technical University Delft in the Netherlands, where she held a post-doctorate position. She has since returned to Australia and is based at the University of Sydney Station Q partnership with Microsoft.

    University of Sydney Professor David Reilly is the director of Station Q Sydney.

    “This is practical science at the cutting-edge,” Professor Reilly said. “We have hired Dr Cassidy because her ability to fabricate next-generation quantum devices is second to none.”

    He said Dr Cassidy was one of many great minds attracted to work at Station Q Sydney already this year. “And there are more people joining us soon at Sydney as we build our capacity.”

    Professor Reilly last week won the Australian Financial Review award for Emerging Leadership in Higher Education.

    See the full article here .

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
  • richardmitnick 7:07 am on July 10, 2017 Permalink | Reply
    Tags: , , , Explainer: what is cancer radiotherapy and why do we need proton beam therapy?, , Proton Beam Therapy, Radiation cancer therapy, U Sidney   

    From COSMOS via U Sidney: “Explainer: what is cancer radiotherapy and why do we need proton beam therapy?” 

    U Sidney bloc

    University of Sidney

    COSMOS

    10 July 2017
    Paul Keall

    Proton beam therapy is radiation therapy that uses heavier particles instead of the X-rays used in conventional radiotherapy.

    2
    1
    Both above from New Jersey’s ProCure Proton Therapy Center

    In the 2017 federal budget, the government dedicated up to A$68 million to help set up Australia’s first proton beam therapy facility in South Australia. The government says this will help Australian researchers develop the next generation of cancer treatments, including for complex children’s cancers.

    Proton beam therapy is radiation therapy that uses heavier particles (protons) instead of the X-rays used in conventional radiotherapy. These particles can more accurately target tumours closer to vital organs, which can be especially beneficial to patients suffering from brain cancer and children whose organs are still developing and are more vulnerable to damage.

    So, the facility will also be an alternative to conventional radiotherapy for treating certain cancer. But what is traditional radiotherapy, and how will access to proton beam therapy improve how we manage cancer?

    What is radiotherapy?

    Radiotherapy, together with surgery, chemotherapy and palliative care, are the cornerstones of cancer treatment. Radiotherapy is recommended for half of cancer patients.

    It is mostly used when the cancer is localised to one or more areas. Depending on the cancer site and stage, radiotherapy can be used alone or in combination with surgery and chemotherapy. It can be used before or after other treatments to make them more effective by, for example, shrinking the tumour before chemotherapy or treating cancer that remains after surgery.

    Most radiotherapy treats cancer by directing beams of high energy X-rays at the tumour (although other radiation beams, such as gamma rays, electron beams or proton/heavy particle beams can also be used).

    The X-rays interact with tumour cells, damaging their DNA and restricting their ability to reproduce. But because X-rays don’t differentiate between cancerous and healthy cells, normal tissues can be damaged. Damaged healthy tissue can lead to minor symptoms such as fatigue, or, in rare cases, more serious outcomes such as hospitalisation and death.

    Getting the right amount of radiation is a fine balance between therapy and harm. A common way to improve the benefit-to-cure ratio is to fire multiple beams at the tumour from different directions. If they overlap, they can maximise the damage to the tumour while minimising damage to healthy tissue.

    How it works

    3
    A drawing of the X-ray machine used by Wilhelm Röntgen to produce images of the hand. Golan Levin/Flickr, CC BY-SA

    Wilhelm Röntgen discovered X-rays in 1895 and within a year, the link between exposure to too much radiation and skin burns led scientists and doctors to pursue radiation in cancer treatment.

    There are three key stages in the radiotherapy process. The patient is first imaged – using such machines as computer tomography (CT) or magnetic resonance imaging (MRI). This estimates the extent of the tumour and helps to understand where it is with respect to healthy tissues and other critical structures.

    In the second stage, the doctor and treatment team will use these images and the patient’s case history to plan where the radiation beams should be placed – to maximise the damage to the tumour while minimising it to healthy tissues. Complex computer simulations model the interactions of the radiation beams with the patient to give a best estimate of what will happen during treatment.

    4
    A single radiotherapy treatment takes 15 to 30 minutes. IAEA Imagebank/Flickr, CC BY

    During the third, treatment-delivery stage, the patient lies still while the treatment beam rotates, delivering radiation from multiple angles.

    Each treatment generally takes 15 to 30 minutes. Depending on the cancer and stage, there are between one and 40 individual treatments, typically one treatment a day. The patient cannot feel the radiation being delivered.

    Benefits and side effects

    Radiotherapy’s targeting technology has made a significant difference to many cancers, in particular early-stage lung and prostate cancers. It is now possible to have effective, low toxicity treatments for these with one to five radiotherapy sessions.

    For early-stage lung cancer studies estimate with radiotherapy, survival three years after diagnosis is at 95%. For prostate cancer, one study estimates survival at the five year mark is about 93%.

    Side effects for radiotherapy vary markedly between treatment sites, cancer stages and individual patients. They are typically moderate but can be severe. A general side effect of radiotherapy is fatigue.

    5
    Radiotherapy is often used to treat brain tumours. Eric Lewis/Flickr, CC BY

    Other side effects include diarrhoea, appetite loss, dry mouth and difficulty swallowing for head and neck cancer radiotherapy, as well as incontinence and reduction in sexual function for pelvic radiotherapy.

    Long-term effects of radiotherapy are a concern, particularly for children. For instance, radiation to treat childhood brain tumours can have long-lasting cognitive effects that can affect relationships and academic achievement.

    Again doctors will need to weigh up the risks and benefits of treatment for individual patients. Proton beam therapy is arguably most beneficial in these cases.

    Other radiotherapy challenges

    There are several challenges to current radiotherapy. It is often difficult to differentiate the tumour from healthy tissue, and even experts do not always agree on where exactly the tumour is.

    Radiotherapy can’t easily adapt to the complex changes in patients’ anatomy when a patient moves – for instance, when they breathe, swallow, their heart beats or as they digest food. As a result, radiation beams can be off-target, missing the tumour and striking healthy tissue.

    Also, we currently treat all parts of the tumour equally, despite knowing some of the tumour’s regions are more aggressive, resistant to radiation and likely to spread to other parts of the body.

    The tumour itself also changes in response to the treatment, further confounding the problem. An ideal radiotherapy solution would image and adapt the treatment continuously based on these changes.

    Improvements in technology, including in imaging systems that can better find the tumour, can help overcome these challenges.


    Proton therapy requires large accelerators to give protons enough energy to penetrate deep into patients. No video credit.

    Proton beam therapy and other innovations

    Proton beam therapy will help maximise benefits for many patients, including those with cancers near the spinal cord and pelvis. It requires large accelerators to give protons enough energy to penetrate deep into patients. The energetic protons are transported into the treatment room using complex steering magnets and directed to the tumour inside the patient.

    Protons slow down and lose energy inside the patient, with most of the energy loss planned to occur in the tumour. This reduces energy loss in healthy tissues and reduces side effects.

    The problems of changing patient anatomy and physiology in other forms of radiotherapy are also challenges for proton beam therapy.

    The ConversationAustralia has a number of research teams tackling such challenges, including developing new radiation treatment devices, breathing aids for cancer patients, radiation measurement devices, shorter and more convenient treatment schedules and the optimal combination of radiotherapy with other treatments, such as chemotherapy and immunotherapy.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
  • richardmitnick 10:57 am on February 15, 2017 Permalink | Reply
    Tags: Faint polarized flares detected from the variable star UV Ceti, , or Luyten 726-8B, , U Sidney, UV Ceti   

    From U Sidney via phys.org: “Faint, polarized flares detected from the variable star UV Ceti” 

    U Sidney bloc

    University of Sidney

    phys.org

    phys.org

    February 15, 2017
    Tomasz Nowakowski

    1
    Faraday dispersion function of UV Ceti at 154 MHz during the off and on period of the Dec. 11, 2015 flare. Credit: Lynch et al., 2017.

    Astronomers have detected four faint, polarized flares at 154 MHz from the nearby variable star UV Ceti. The newly observed flares are much fainter than most flares found at these frequencies. The findings were presented February 10 in a paper published online on the arXiv pre-print server.

    Located just about 8.7 light years away, UV Ceti, or Luyten 726-8B, belongs to a nearby binary star system Luyten 726-8.

    3
    Luyten 726-8 AB / UV Ceti http://www.solstation.com/stars/luy726-8.htm

    It is a variable red dwarf of spectral type M, just like its companion star BL Ceti (Luyten 726-8A). Due to its proximity, this star system is a treasure trove for astronomers studying flaring events of magnetically active stellar systems.

    That is why a team of researchers led by Christene Lynch of the University of Sydney in Australia selected UV Ceti as a target of radio astronomy observations in December 2015. They used the Murchison Widefield Array (MWA) in Australia to confirm previous bright flare detections in the system at 100 to 200 MHz.

    SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO), 800 kilometres north of Perth
    SKA Murchison Widefield Array, Boolardy station in outback Western Australia, at the Murchison Radio-astronomy Observatory (MRO), 800 kilometres north of Perth

    The array allowed the scientist to get a glimpse of low-level flares fainter than expected.

    “We have detected four flares from UV Ceti at 154 MHz using the Murchison Widefield Array,” the paper reads.

    The observation sessions, which used a 30.72 MHz bandwidth centered at 154 MHz with 40 kHz channels and 0.5-second integrations, allowed the team to observe flare emission in the polarized images. In each epoch, they detected a single right-handed circularly polarized flare, finding also a left-handed flare immediately following the right-handed one. Moreover, they detected linear polarization during the brightest flare, what indicates that the flares are elliptically polarized. The researchers noted that these results highlight the importance of polarization images in such studies.

    “These dim flares are only detected in polarized images, which have an order of magnitude better sensitivity than the total intensity images. This highlights the utility of using polarization images to detect low level emission in confusion limited images,” the team wrote in the paper.

    The study also revealed that the newly detected flares have flux densities between 10 to 65 mJy. This means that they are about 100 times fainter than most flares observed so far at similar frequencies. Notably, three of the four flares described in the paper have flux densities below 15 mJy, while the one observed on Dec. 11, 2015 reached nearly 65 mJy.

    The researchers emphasize that their study provides first flare rate measurements for low-intensity (below 100 mJy) flares at 100 to 200 MHz. However, they note that there is still much to accomplish in the field of flare emission research and recommend further observations. Future studies would improve our understanding of physical parameters of the stellar magnetospheric plasma.

    “To better characterize M dwarf flares at meter wavelengths requires more observational time on individual sources to constrain flare rates. More sensitive observations are also needed to investigate the fine time-frequency structure of the flares. Simultaneous multi-wavelength observations would also add to this analysis,” the team concluded.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
  • richardmitnick 4:46 am on May 12, 2016 Permalink | Reply
    Tags: , How the Hawaiian-Emperor seamount chain got its spectacular bend, , U Sidney   

    From U Sidney: “How the Hawaiian-Emperor seamount chain got its spectacular bend” 

    U Sidney bloc

    University of Sidney

    12 May 2016
    Vivienne Reiner
    Media and PR Adviser (Science, Veterinary Science, Agriculture)
    Phone
    +61 2 951 2390
    +61 438 021 390
    Email
    vivienne.reiner@sydney.edu.au
    Address
    Room 192, Level 1 Carslaw F07

    Researchers used a world-leading supercomputer, revealing flow patterns just above the Earth’s core 100 million years old.


    Access mp4 video here .
    Rapid southward motion of the Hawaiian plume, followed by a sharp slowdown, causes the sharp bend in the Hawaiian-Emperor seamount chain. Created by Rakib Hassan, University of Sydney.

    1
    Hawaiian-Emperor seamount chain. Source: University of Sydney

    The physical mechanism causing the unique, sharp bend in the Hawaiian-Emperor seamount chain has been uncovered in a collaboration between the University of Sydney and the California Institute of Technology (Caltech).

    Led by a PhD candidate at the University of Sydney’s School of Geosciences, researchers used the Southern Hemisphere’s most highly integrated supercomputer to reveal flow patterns deep in the Earth’s mantle – just above the core – over the past 100 million years.

    U Sidney Raijin Fujitsu supercomputer
    U Sidney Raijin Fujitsu supercomputer

    The flow patterns explain how the enigmatic bend in the Hawaiian–Emperor seamount chain arose.

    True to the old adage – as above, so below – the Sydney-US collaboration found the shape of volcanic seamount chains (chains of mostly extinct volcanoes), including Hawaii, is intimately linked to motion near the Earth’s core.

    The findings* of PhD candidate Rakib Hassan and fellow researchers including Professor Dietmar Müller from the University’s EarthByte Group, are being published in Nature.

    Mr Hassan explained: “Until now, scientists believed the spectacular 60° bend in the Hawaiian seamount chain – not found in any other seamount chains – was related to a change in plate motion combined with a change in flow direction in the shallow mantle, the layer of thick rock between the Earth’s crust and its core.

    “These findings suggest the shape of volcanic seamount chains record motion in the deepest mantle, near the Earth’s core. The more coherent and rapid the motion deep in the mantle, the more acute its effects are on the shape of seamount chains above,” he said.

    Although solid, the mantle is in a state of continuous flow, observable only over geological timescales. Vertical columns of hot and buoyant rock rising through the mantle from near the core are known as mantle plumes. Volcanic seamount chains such as Hawaii were created from magma produced near the surface by mantle plumes. Moving tectonic plates sit above the mantle and carry newly formed seamounts away from the plume underneath – the oldest seamounts in a chain are therefore furthest away from the plume.

    “We had an intuition that, since the north Pacific experienced a prolonged phase where large, cold tectonic plates uninterruptedly sank into the mantle, the flow in the deepest mantle there would be very different compared to other regions of the Earth,” Mr Hassan said.

    One of the most contentious debates in geoscience has centred on whether piles of rock in the deep mantle – to which plumes are anchored – have remained stationary, unaffected by mantle flow over hundreds of millions of years.

    The new research shows the shapes of these piles have changed through time and their shapes can be strongly dependent on rapid, coherent flow in the deep mantle.

    Between 50-100 million years ago, the edge of the pile under the north Pacific was pushed rapidly southward, along with the base of Hawaii’s volcanic plume, causing it to tilt. The plume became vertical again once the motion of its base stopped; this dramatic start-stop motion resulted in the seamount chain’s sharp bend.

    Using Australia’s National Computational Infrastructure’s supercomputer Raijin, the team created high-resolution three-dimensional simulations of mantle evolution over the past 200 million years to understand the coupling between convection in the deep Earth and volcanism.

    Mr Hassan said the simulations were guided by surface observations – similar to meteorologists applying past measurements to predict the weather.

    “These simulations required millions of central processing unit (CPU) hours on the supercomputer over the course of the project,” he said.

    Professor Müller concluded: “Our results help resolve a major enigma of why volcanic seamount chains on the same tectonic plate can have very different shapes.

    “It is now clear that we first need to understand the dynamics of the deepest ‘Underworld’, right above the core, to unravel the history of volcanism at Earth’s surface,” said Professor Müller.

    The paper, ‘A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow’, will be published this week in Nature.

    *Science paper:
    A rapid burst in hotspot motion through the interaction of tectonics and deep mantle flow

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    U Sidney campus

    Our founding principle as Australia’s first university was that we would be a modern and progressive institution. It’s an ideal we still hold dear today.

    When Charles William Wentworth proposed the idea of Australia’s first university in 1850, he imagined “the opportunity for the child of every class to become great and useful in the destinies of this country”.

    We’ve stayed true to that original value and purpose by promoting inclusion and diversity for the past 160 years.

    It’s the reason that, as early as 1881, we admitted women on an equal footing to male students. Oxford University didn’t follow suit until 30 years later, and Jesus College at Cambridge University did not begin admitting female students until 1974.

    It’s also why, from the very start, talented students of all backgrounds were given the chance to access further education through bursaries and scholarships.

    Today we offer hundreds of scholarships to support and encourage talented students, and a range of grants and bursaries to those who need a financial helping hand.

     
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