Definition of a Medical Physicist (MP)
“Medical Physicist”
According to the definition of the International Basic Safety Standards (BSS) , is “a health professional, with specialist education and training in the concepts and techniques of applying physics in medicine, and competent to practise independently in one or more of the subfields (specialties) of medical physics.”
Qualifications of a Medical Physicist
Medical physicists must have received appropriate undergraduate education in physical or engineering sciences, followed by a professional competency training that includes an additional period of 1–3 years of academic education in medical physics at the postgraduate level. In order to become a clinically qualified medical physicist (CQMP), the academic training at the postgraduate level must be followed by at least two additional years of structured practical training in a clinical environment, in one or more specialties of medical physics. Overall, the academic education and clinical training should extend over a minimum period of, typically, seven years. Medical physicists that have completed an academic programme and work or do research in a non-clinical environment will require additional appropriate training to become CQMPs. The education and training of medical physicists should be recognized by a national or international accreditation body.
Scope of Practice for a Medical Physicist (common for all specialisations)
Medical physicists contribute to the safe and effective use of radiation in order to achieve the best diagnostic or therapeutic outcome of the prescribed medical procedure. To achieve this, they:
• Evaluate practices that involve medical exposure and optimize the physical aspects of diagnostic and therapeutic procedures in terms of benefits and risks.
• Calibrate imaging equipment to ensure accurate and safe delivery of radiation to patients.
• Implement appropriate quality assurance programmes, including quality control measures.
• Assess radiation doses and associated risks to patients (especially for pregnant women and children) and personnel.

Most medical physicists work in cancer treatment facilities, hospital diagnostic imaging departments or hospital-based research establishments, and mostly specialize in three areas of activity: clinical service and consultation, research and development, and teaching.

The three core areas where medical physicist practice:
Clinical service and consultation
• The Medical Physicist’s work often involves the use of x-rays, ultrasound, radioisotopes, magnetic and electric fields in diagnosis and therapy. These activities take the form of clinical consultations with health other professionals. In radiotherapy departments, physicists have a central role in planning individual patients’ radiation treatment using either external radiation beams or internally placed radioactive sources.
• Medical Physicists also have a role to play in diagnostics. For example, they might analyse nuclear medical image data to determine important physiological variables, such as metabolic rates or blood flow.
• Physicists provide an essential radiation protection and radiation safety service, providing scientific and technical consultancy on the design of radiation facilities and the safe handling, storage and disposal of radioactive materials.
• Similar consultancy services are provided for the specification, procurement and acceptance testing of complex and expensive medical equipment including radiotherapy linear accelerators and imaging equipment such as X-ray CT scanners and MRI scanners.
• Another important clinical duty of the medical physicist is to design and manage quality assurance and preventative maintenance programmes (often in close collaboration with manufacturers) to ensure that equipment remains safe and accurate.
• Finally, the specialist clinical scientific and technical knowledge of the physicist is frequently called upon to diagnose faults and problems that arise with such specialized and complex equipment.
Research and Development
Medical physicists are also involved at the frontiers of research at all levels:
• Basic, theoretical studies into new physical concepts that might be used for diagnosis and treatment
• Development and testing of equipment
• The conduct of clinical trials of new imaging and treatment techniques.
• Medical research work is almost always highly collaborative and multi-disciplinary. Collaborations typically involve basic scientists in universities, equipment manufactures and a range of different medical professionals, including radiographers, radiologists and radiation oncologists.
• The recent rapid technical developments in equipment used in medical imaging and therapy mean that there is always a need for applied research and development work within hospitals. Finding the optimum way to use new equipment and designing practical and robust methods for implementing technology in a busy clinical workplace are challenges that face most medical physicists are some stage.

From this distant vantage point, the Earth might not seem of particular interest. But for us, it's different. Consider again that dot. That's here, that's home, that's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.

Carl Sagan, from his book THE PALE BLUE DOT originally published in 1994. The book was inspired by a photo taken by Voyager1 space probe in February, 1990 about 6 billion kilometers from Earth.

O, the complexity of existence! Blind we are when our's begins and blind shall we be when our's ends. We know not by our own selves the hour in which we were conceived, nor the hour in which we were birthed. We took no part in deciding when, where, or how we were to be born. And concerning our end, perhaps we may be playing a role, but its fulfillment remains still quite uncertain.

Let the thoughts of life and death abide in the hearts and minds of anyone who wishes to philosophize accordingly. Understanding the scope of one's ignorance is critically vital for any intelligent mind. It is very important to question oneself the fundamental questions about life, about one's existence and one's end. These are not easy questions for the mind and heart, nevertheless, every one of us ought to not necessarily solve them, but at least face them - to stop for a while and think about them. Why am I here? Where did I come from? What is my purpose in this life? What happens to me when I die? One question after the other...Pause. Think. Philosophize.

We know so little. We understand so less. We do not question our knowledge because we think we know. Sometimes, we simply fear to think because we are afraid of where our thoughts may lead us. We love certainty. We love our strongly held beliefs. We don't want them challenged. But, I say to you my dear friends, in an honest pursuit of truth and understanding, let ALL ideas be challenged. At the end, when all shaking has been done, the truth will always stand.

Various religions provide different answers to questions concerning life and death. It's all a matter of faith. Faith, in all its elegance and all its beauty, provides little or no explanation for its claims. You need only to believe, and so we do, in accordance with our religion. Science, on the other hand, does not have all the answers to these questions but provides some explanation in correspondence with present evidence and understanding. As intelligent beings, we need explanations. As spiritual and emotional beings, we need faith. So both are essential.

Whether it be us or the generations to come which will provide explanations to such philosophical questions, let us ensure to build a society and a world which accommodates both religious and scientific concepts when it comes to answering the questions about origins, life, existence, and death. Let us not be too quick to dismiss everything we do not understand and every concept which seems to challenge our long-held views. Let us work together to build a better world where differences don't divide us; be it religion, politics, tribes, race, and so forth. And above all my dear friends, let us keep loving one another! Let us promote a society that will fully embrace science and philosophy in an attempt to raise a generation more informed about themselves and the world in which they live. I believe peace, unity, and development come when there is understanding and when there is cooperation. Not everyone who disagrees with you is your enemy. This is no parable, but plain simple truth.

In the last few years, society has witnessed rapid advances in electronics that have found uses in applications such as computing and photonics, affecting just about every aspect of our lives. Many of these advances have been the result of the continuous downscaling of electronic devices. However, performance enhancement via device scaling approaches a limit. There are several limitations that put a restraint on the size and performance of devices [1]. When natural materials meet their physical limit, metamaterials are utilized for their unusual electromagnetic properties that are not found in naturally occurring materials. A natural material has positive electrical permittivity, magnetic permeability, and an index of refraction. Metamaterials can have some or all these parameters be negative [2].

Thermophotovoltaic devices, for example, can be used to increase the efficiency of solar panels by absorbing the waste heat and emitting light, which can be absorbed by the solar cells. Thermophotovoltaics, a type of photonic device, can absorb electromagnetic radiation from processes producing heat, which would otherwise dissipate and be wasted, into utilizable electricity [3]. With the use of heat resistant hyperbolic materials with broad dispersion spectra, more energy can be converted into usable electricity [4]. Waste heat accounts for 67% of the energy used in energy production in the US alone [4]. Therefore, the application of such technology would have great prospects. Thermal photons are photons emitted from a hot body. As Infrared radiation is a small component of the electromagnetic spectrum, all hot surfaces emit light as thermal radiation. The problem with photonics is that thermal radiation is broadband, while the conversion of light to electricity is efficient only if the emission is in a narrowband [4] [5].

Past photonics attempt to put broadband photons into a narrow band, but HMMspresent an opportunity to absorb mid-infrared photons that would be wasted otherwise. There are HMMs that absorb waste heat and turn it into narrow-bandwidth photons [5]. Electrons in HMMs can only travel in one direction. These anisotropic materials are metallic in one direction while insulating in the perpendicular direction. The high-k waves supported in the hyperbolic mediums give significantly higherPDOS. The smallest cavities, the volume of∼λ3/700, in single walled carbon nanotubes(SWCNT) for example, display a resonance corresponding with at least a 100 times enhancement of PDOS in SWCNT compared to blackbody radiation [4].

REFERENCES
[1] Jes ́us A. del Alamo. Nanometre-scale electronics with iii-v compound semiconductors.Nature, 479(7373):317–323, 2011.

[2] R. S. Kshetrimayum. A brief intro to metamaterials.IEEE Potentials, 23(5):44–46, 2005.

[3] Lorenzo Ferrari, Dylan Lu, Dominic Lepage, and Zhaowei Liu. Enhanced spontaneous emission inside hyperbolic metamaterials. Opt. Express, 22(4):4301–4306, Feb 2014.

[4] Weilu Gao, Chloe F. Doiron, Xinwei Li, Junichiro Kono, and Gururaj V. Naik.Macroscopically aligned carbon nanotubes as a refractory platform for hyperbolic thermal emitters.ACS Photonics, 6(7):1602–1609, Jul 2019.

[5] J. D. Joannopoulos, Pierre R. Villeneuve, and Shanhui Fan. Photonic crystals: putting a new twist on light. Nature, 386(6621):143–149, 1997

Source: Hyperbolic Metamaterials and Applications, S. Young, T. Kabengele, Solid State Physics course project, Dalhousie University, 2020.

Fast reactors are a class of advanced nuclear reactors that have some key advantages over traditional reactors in safety, sustainability, and waste. While traditional reactors contain moderators, such as water used in the VVER, to slow down neutrons after they’re emitted, fast reactors keep their neutrons moving quickly. Fast neutron reactors exploit the vast energy in the uranium U-238 isotope in addition to that of the uranium U-235 isotope exploited by most modern thermal reactors.

Natural uranium consists mostly of three isotopes: U-238, U-235, and trace quantities of U-234, a decay product of U-238. U-238 accounts for roughly 99.3% of natural uranium and undergoes fission only by fast neutrons. It is turned into several isotopes of plutonium, of which Pu-239 and Pu-241 then undergo fission in the same way as U-235 to produce heat. This process is optimized so that uranium is utilized about 60 times more efficiently than conventional thermal reactors.

Fast neutron reactors can reduce the total radiotoxicity of nuclear waste by using all or almost all of the waste as fuel. Since disposal of the fission products is dominated by the most radiotoxic fission product, caesium-137, which has a half-life of 30.1 years, the result is to reduce nuclear waste lifetimes from tens of millennia (from transuranic isotopes) to a few centuries. Fast reactors get more neutrons out of their primary fuel than thermal reactors, so many can be used to breed new fuel thus greatly enhancing the sustainability of nuclear power. Fast reactors typically use liquid metal coolants rather than water. These coolants, such as liquid sodium, have superior heat-transfer properties. Another advantage of the reactors is their strong negative temperature coefficient (the reaction slows as the temperature rises unduly) which allows them to remove the heat in even severe accident scenarios, causing a safer and more effective shutdown.

There are 12 experimental fast reactors and six commercial size prototypes with outputs from 250 – 1200 Megawatts that have been constructed or are in operation. The Russian Federation currently operates the most powerful commercial fast neutron reactor, the BN-600 in Beloyarsk which has been supplying electricity to the grid since 1980 and is said to have the best operating and production record of all Russia's nuclear power units.

The advantages that the implementation of fast neutron reactors comes with are visible. Present research prospects are to make the fast neutron reactor safer, more cost effective and more efficient. There are programmes ongoing to develop and implement innovative fast nuclear energy systems in China, France, India, Japan, the Republic of Korea, the Russian Federation, among other countries.

REFERENCES
1. Smarter use of Nuclear Waste – William H. Hannum, Gerald E. Marsh and George S. Stanford, 2005
2. "Fast Neutron Reactors" – World Nuclear Association.
3. Fast Breeder Reactors – Richard L. Garwin
4. Fast Neutron Reactor – www.nuclear-power.net.
5. Fast Reactor – whatisnuclear.com
6. Fast Reactors Provide Sustainable Nuclear Power for "Thousands of Years" – Peter Kaiser, Peter Rickwood, IAEA Division of Public Information