Liquid metals are used in everything from thermostats and barometers to wearable devices. Scientists say that these metals may also eliminate some surgical or endoscopic procedures – by dissolving implantable devices made from solid metals on command.
“Because of their excellent mechanical strength, metals are very useful for making medical devices that need to resist large forces, like long-term drug delivery systems. For these kinds of devices to be broadly accessible to patients, we also need non-invasive methods of removing them from the body,” says Vivian Feig, a postdoctoral research fellow at MIT and Brigham and Women’s Hospital.
Feig is the lead author on a recent study demonstrating how gallium alloys, which are in liquid state at body temperature, can break down aluminium-based devices. In the future, the researchers hope that they can trigger more clinically relevant metals, such as titanium, to break down upon exposure to gallium.
Intentional metal failure
Liquid metal embrittlement, a phenomenon that leads to fractures in metal, is the key to the researchers’ method for dissolving metal implantable devices. “Liquid metal embrittlement is a fairly well-studied phenomenon that has been historically treated as a failure mechanism meant to be avoided,” Feig explains.
But Feig and the team were looking for ways to build medical devices out of tough, durable materials that can also be prompted to break down after use. Most actively triggerable materials to date have been made from polymers, which aren’t as strong as metals. What if, the researchers reasoned, a liquid metal like gallium could be used as a biocompatible trigger “that leverages embrittlement in a productive manner to address a clinically-important challenge”.
The result: repurposing an alloy of gallium called eutectic gallium indium (EGaIn).
Scientists have already explored EGaIn for a variety of applications in biomedicine, energy and flexible electronics. Feig and her team tested whether EGaIn could be formulated for targeted breakdown of aluminium in the body. In their recent study, described in Advanced Materials, they performed experiments to initiate embrittlement in EGaIn and control its breakdown. They also demonstrated potential biomedical uses of EGaIn and performed some biocompatibility studies.
Medical application Prototype of a gastric resident device with polymeric components linked via aluminium tubes. The device can be broken down in the digestive tract upon treatment with EGaIn. (Courtesy: MIT/the researchers)
The researchers’ functional formulation of EGaIn weakens aluminium by diffusing through a metal’s grain boundaries – border lines between crystals that make up the metal – which causes pieces of the metal to break off. EGaIn also prevents aluminium from forming a protective oxide layer on its surface, which increases the aluminium’s exposure to water and enhances its degradation.
Aluminium devices painted with EGaIn disintegrate within minutes, experiments showed. The researchers also created nanoparticles and microparticles of gallium-indium and demonstrated that these particles, suspended in fluid, could also break down aluminium structures.
Feig says that EGaIn could be painted onto staples used to hold skin together, causing the staples to disintegrate on-demand and preventing damage that can occur during procedures to remove them. EGaIn could also be used to break down stents implanted in oesophageal tissue. To date, stents are left in the body permanently or removed endoscopically.
Next, the researchers will perform extensive biocompatibility testing, exploring applications for EGaIn in different physiological environments and studying how different metals respond to EGaIn. The team is also working to address changes in liquid metal performance arising when metal surfaces are coated by proteins and other endogenous materials.
“We hope this work can inspire others to think about failure mechanisms like embrittlement in a different way – as processes that can actually be beneficial for addressing certain biomedical challenges,” Feig says. “Now, we are delving deeper into understanding how we can make metals more susceptible to embrittlement. This knowledge will help us apply our work to a wider range of clinically relevant metals, beyond aluminium.”
My job involves collaborating with colleagues from physics, physiology, mathematics and engineering; based in both academia and industry. This means that the day-to-day activities I’m involved in are exciting but challenging at the same time, as none of us are experts in all aspects of the project. We have to work to understand each other’s perspectives and priorities. One of the key skills needed in such an environment is effective communication techniques, which help me to explain highly technical fundamental physics concepts to non-physicists while also helping me understand complex principles from beyond my areas of expertise. Developing the skills to communicate with different disciplines and sectors has been vital to ensure effective working and to minimize errors.
Working in diverse teams also means I am constantly learning and adapting, and finding interesting new ways to apply my technical skills and knowledge to real-world problems. In academia I mostly worked in labs, using experimental setups. However, since moving into industry I spend the majority of my time working on simulations and mathematical modelling. This transition has been challenging but rewarding, and has allowed me to develop the technical skills that are in high demand in my sector. Being adaptable and able to learn new skills on the job has made me a more well-rounded researcher.
What do you like best and least about your job?
I enjoy the diversity of the environment I work in and the applied nature of the physics we are conducting. Working in industry, I have engaged in research with real-world impact and am often involved in projects from concept to implementation. I have the flexibility to apply my ideas and explore interesting research questions alongside many collaborators, and can drive the research agenda of the company. This has given me more autonomy and independence than I could have had in a traditional academic environment, especially in the early stages of my career.
While the flexibility of my job is a real positive, it can be challenging at times due to the constantly changing nature of the work and the complexity of coordinating multiple collaborative activities. This becomes even more difficult when you consider we have colleagues in different time-zones. It does become more manageable as you gain experience, and in the process you learn invaluable organizational and managerial skills. Moreover, there is a great sense of personal and professional satisfaction when you successfully execute the collaborative activities.
What do you know today that you wish you knew when you were starting out in your career?
When I transitioned to physics from engineering, I thought that the skills I had gained in my previous training as an electronics engineer would not be very useful. However, I have used them in every research project I have worked on. I also found that having a mixed technical background helps me tackle a wide range of challenges in distinct ways. I wish I had known that having a non-traditional background and skills beyond specific technical aspects of physics could be beneficial when I made the transition to physics. As innovation requires more and more interdisciplinary work to address complex challenges, so having a wide skill-set is a real positive and I would encourage all early-career researchers to consider branching out beyond traditional subject-specific topics whenever they get the chance.
I also wish I had known that you can do fundamental research outside academia. After I completed my PhD, I initially thought that I would only have the opportunity to do pure research if I pursued an academic path. However, I have now discovered that there are great opportunities to build a research-focused physics career in industry. Recognizing that these career paths exist earlier in your career can be really beneficial to your long-term plans.
A new type of solar cell based on heterojunctions between different crystalline phases of the same light-absorbing material boasts a maximum power conversion of 20.1% and is stable for long periods of time. The concept, developed by researchers at the Technische Universität Dresden (TUD) in Germany, could be applied to cells made from other so-called polymorphic material systems, as well as to other types of optoelectronic devices such as light-emitting diodes and photodetectors.
Modern solar cells often contain a heterojunction – a structure in which two components with different optoelectronic properties meet at an interface. The properties of these components are usually tuned by using different materials or by doping the same material so that one side of the junction has an excess of electrons (n-doped) while the other has an excess of positively-charged holes (p-doped).
Two polymorphs of caesium lead iodide
Researchers led by Yana Vaynzof have now developed a new type of heterojunction solar cell that uses two polymorphs, or phases, of a single material: caesium lead iodide. This material is a perovskite and highly efficient at absorbing light at wavelengths in the Sun’s spectrum, and the optoelectronic properties of its gamma and beta phases are different. By placing the gamma-perovskite atop the beta-perovskite, the researchers succeeded in fabricating a solar cell that is much more efficient than cells based on single-phase perovskites.
According to Vaynzof and colleagues, who report their work in Nature Energy, the top layer of gamma-perovskite improves the performance of the solar cells by passivating defects at the surface of the bottom beta-phase layer. These defects usually trap photoactivated charge carriers (electrons and holes), preventing them from propagating to the opposite side of the photovoltaic device and producing electric current.
The phase heterojunction also increases the cell’s performance in other ways, Vaynzof adds. “Light absorption in the phase heterojunction structure is enhanced as compared to each of the single phases, and the alignment between the energy levels of the two phases results in a beneficial energetic landscape with the solar cell to drive the charge carriers to be separated,” she explains.
‘An entirely new concept for photovoltaics’
The TUD team made its solar cell by depositing the bottom beta-phase and top gamma-phase using techniques called solution processing and thermal evaporation, respectively. Both techniques require only moderate temperatures and combining them produces a sharp interface between the two phases. The phase heterojunction is also stable over long time periods.
“Considering that phase heterojunction solar cells are an entirely new concept for photovoltaics, we foresee that such a concept may also be applied to other polymorphic materials systems” Vaynzof tells Physics World. “It is also possible that such a concept could be applied to other types of optoelectronic devices such as light-emitting diodes and photodetectors.”
The researchers are now exploring different phase heterojunction configurations for other perovskite compositions. They are also exploring alternative photovoltaic device architectures. “Importantly, we aim to use only thermal evaporation as the deposition method to enable the fabrication of multi-layered structures without the limitations that arise from the use of solvents in solution processing,” Vaynzof says. “Since thermal evaporation is a highly scalable, industrially-relevant method, this will facilitate the future integration of phase heterojunctions in industrial applications.”
Theoretical physicists at Rice University in the US have proposed a practical new approach to growing carbon nanotubes with a single chosen “handedness”, or chirality. If realized experimentally, the approach would fulfil a long sought-after goal in nanotechnology and could make nanotube-based technologies more accessible.
Carbon nanotubes (CNTs) are rolled-up hexagonal lattices of carbon just one atom thick. Thanks to their excellent electrical and mechanical properties, they show promise for many applications, including ultra-strong fibres and conductive wires. They can be single-walled or multi-walled, and the way the hexagons are angled within the lattices – their chirality – determines whether they are metallic or semiconducting.
Nanotubes normally grow in a way that produces single and multiple walls and different chiralities at random. However, some applications (like highly conductive fibres or the semiconductor channels of transistors) require batches with just one type of chirality. Separation techniques such as centrifuging can meet this need, but they are complex and costly.
Growing like Lamarck’s giraffes
The new approach developed by Boris Yakobson and Ksenia Bets at Rice requires would-be chiral nanotube growers to set up an optimized localized zone in the CNT growth chamber. This zone contains a precursor feedstock from which the CNTs are created, and Yakobson and Bets’ “recipe” calls for it to move along the reactor at a prescribed speed, allowing only some types of CNT to be “fed”. Since tubes with different chiralities grow at different speeds, they can then be separated by length, leaving the slower-growing types behind.
The researchers describe their method with an analogy to “Lamarck’s giraffes” – a 19th-century theory suggesting that giraffes evolved long necks due to a gradual evolutionary selection of animals that can reach progressively higher for tree leaves to eat.
“It works as a metaphor because you move your ‘leaves’ away, the tubes that can reach them continue growing fast and those that cannot just die out,” says Bets. “Eventually all the nanotubes that are just a tiny bit slow will ‘die’.”
As the main obstacle to widespread industrial use of nanotubes, an in-growth method of chirality selection was a highly-coveted goal for researchers in this field, says Yakobson. “Our new technique can unlock many CNT-based technologies developed over the last decades for mass production,” he claims. “Indeed, chirality selection means single, well-defined electronic bandgaps for transistor or well-defined optical properties perhaps for solar cells applications.”
The Rice team, who detail their study in Science Advances, hope their technique will now be realized in a real-world experiment. “Now that the paper has been published, experimental groups worldwide can try implementing this methodology on their particular growth setups, exploring the possibilities and limitations of the approach pushing the technology development even further,” Yakobson tells Physics World.
In this episode of the Physics World Weekly podcast Katherine Morris of the University of Manchester explains how her research on environmental radiochemistry will lead to better ways of storing nuclear waste and remediating contaminated sites. She also talks about how her team uses the UK’s Diamond Light Source to better understand the chemistry of systems containing radioactive materials.
This webinar will demonstrate planning tools available for the Gamma Knife, such as inverse optimization, which can be used to improve plan consistency and quality and, remote access that allow users to contribute and explore plans from any location.
Plan comparisons will be made between manually created clinical plans by an expert planner and inverse optimized plans using the Lightning software.
Following this, we will discuss the potential impact of Lightning optimized plans on treatment delivery and explore techniques to verify delivery of these plans using Gafchromic film.
The webinar, hosted by Benjamin Earner, concludes with a discussion of various real-world scenarios that benefit from remote access in the clinic and how these can improve patient care and user experience.
Benjamin Earner is a principal physicist at the London Gamma Knife Centre, London, UK, which is part of the HCA Healthcare UK network. He has worked with the Gamma Knife Icon for more than six years and has been involved in the commissioning of stereotactic radiosurgery and radiotherapy systems for 14 years. He has a passion for bring innovation and workflow improvements to the clinic, with a particular emphasis on the integration of software solutions. Benjamin has co-authored several articles on the implementation of Gafchromic film for radiotherapy applications.
From Laura Bassi to Marie Curie, for centuries, women have been making important contributions to the world of physics. Now with ViewRay’s MRIdian system, women are leading the charge in bringing the latest advancement of MRI-guided radiation therapy to the forefront of radiation oncology and expanding the medical physics landscape.
Based on American Association of Medical Physicists (AAPM) TG-100, ACR phantoms are used to evaluate the key performance of MR scanners, such as magnetic field homogeneity, geometric accuracy, slice thickness, low-contrast detectability, high-contrast spatial resolution, slice position accuracy, uniformity, and radiofrequency coil checks. Although literature highlights the needs and considerations for QA of MRI simulation in radiotherapy with the ACR phantom, a dedicated QA procedure for radiation oncology is not yet established and available since the commercialization of MRL systems.
The Magphan RT phantom (The Phantom Laboratory, Salem, NY, USA) has been released, providing an integrated test that performs all of the measurements required to ensure MRI performance in MRgRT with an automated analysis platform that facilitates a comprehensive and sophisticated QA of a MR scanner.
This series of five webinars will specifically highlight women physicists across the globe that are using MRIdian to transform cancer care as we know it. Poonam Yadav will discuss different modes of the system, periodic MRI QA and their challenges, establishing time-saving MRI QA and consistency of the results.
This presentation is the second in a series of Women in Medical Physics, supported by ViewRay.
Poonam Yadav, PhD, is an associate professor of radiation oncology at Northwestern University Feinberg School of Medicine. Much of her current work involves the ViewRay MRIdian System, an MRI-guided radiation therapy machine that enables clinicians to monitor tumours and surrounding tissues during treatment. This technology allows us to adapt to changes in the patient’s anatomy to ensure accurate delivery of radiation. Previously, she served as faculty at the University of Wisconsin School of Medicine and Public Health’s Department of Human Oncology, with an affiliate appointment at the University of Wisconsin Carbone Cancer Center where she led numerous research studies, technology implementation, and substantial clinical practice. Poonam has designed and led several clinical physics studies. She finds interdisciplinary approach in radiotherapy quite motivating and to engage with. She is actively involved in investigating a whole host of clinical situations such as ventricular tachycardia, benign diseases and others where patients can benefit from radiation therapy. Poonam is a strong advocate for everyone to have equal access to education and training and has been an advocate for this cause through AAPM and other professional organizations.
The UK must attract highly qualified workers from abroad if the country wants to have a flourishing industry and economy. That is one of four recommendations in a new report released by the House of Lords Science and Technology Committee. The conclusions were reached following an inquiry by the committee last year into science, technology, engineering and mathematics (STEM) skills in the UK.
Led by Julia King, a former chief executive of the Institute of Physics, which publishes Physics World, the inquiry sought to assess whether the UK’s workforce is sufficiently skilled to achieve the government’s ambition of becoming a “science and technology superpower” by 2030.
After hearing from representatives from a range of sectors, including pharmaceuticals and manufacturing, the committee has concluded that there is a widespread shortage of STEM skills, such as mathematics and coding. It also says that the government’s proposed solutions to tackle the shortage are “inadequate and piecemeal”.
To address the skills gap, the committee recommends four policies, the first being to encourage skilled workers from abroad to move to the UK. The report states that overseas talent is a “key” part of the solution and calls on the government to explore new types of visas, revise visa costs and make it easier for small companies to sponsor people from overseas.
The committee’s second recommendation is for a quantitative assessment of exactly which skills are missing in the UK, with routes for people to gain them through apprenticeships and – later in their careers – through modular courses below degree level.
Recruiting and retaining science teachers, particularly in high-demand subjects like physics and computing, is another priority, as is tackling the uncertainty of short-term postdoc work in academia. More should also be done support PhD students to find careers in industry.
Economic focus
To become a science superpower, King says the UK would need a growing STEM culture, excellent teaching, a science-literate population as well as more young people aspiring to STEM jobs. Together with well-funded research in UK universities, this would then fuel a rapid growth in technology companies.
Markers of success for this strategy would include the UK becoming a preferred international research partner as well as a desirable work destination for world-class scientists. Companies would also choose to list on the UK stock market, rather than seeking financial support elsewhere.
“The right skills are critical to the UK’s economic growth,” King told Physics World. “For example, there are many opportunities from the green economy, from retrofitting homes to developing new low-carbon heating technologies to zero-carbon aviation.”
King adds that companies in all areas and of all sizes are reporting skills shortages at technician, graduate and PhD level. “Investment in STEM skills is critical to drive the growth we need to restore the economy and to support critical services such as the NHS,” she says.
The findings from the Lords’ report are detailed in a letter to UK science minister George Freeman published in mid-December. The committee has requested a response from the UK government by 15 February.
BBB opening and deep brain stimulation Schematic showing how systemically administered piezoelectric nanoparticles release NO locally in response to ultrasound and accumulate in the brain via BBB opening. The ultrasound-stimulated nanoparticles then generate current for neural stimulation, resulting in the release of neurotransmitters. (Courtesy: Nat. Biomed. Eng. 10.1038/s41551-022-00965-4)
Deep brain stimulation (DBS), in which electrodes implanted in the brain deliver electrical impulses to specific targets, is an effective clinical treatment for several neurological conditions. DBS is currently used to treat movement disorders such as Parkinson’s disease, essential tremor and dystonia, as well as conditions such as epilepsy and obsessive-compulsive disorder. The treatment, however, necessitates brain surgery to insert the stimulation electrodes, with the potential to cause numerous side effects.
To remove the need for invasive surgery, researchers from Pohang University of Science and Technology (POSTECH) in Korea are developing a non-invasive neural stimulation strategy based on piezoelectric nanoparticles. The nanoparticles serve two functions – transient opening of the blood–brain barrier (BBB) and stimulating the release of dopamine – both controlled by externally applied focused ultrasound.
Piezoelectric nanoparticles are of interest as neural stimulators because in response to external stimuli – such as ultrasound, for example – they deform and output direct current. The researchers propose that this current could then be used to stimulate dopaminergic neurons to release neurotransmitters.
One key challenge is delivering the nanoparticles to the brain, specifically, how to get them across the BBB. To achieve this, the researchers turned to nitric oxide (NO), a highly reactive molecule that shows potential for BBB disruption. They designed a multifunctional system, described in Nature Biomedical Engineering, comprising a barium titanate nanoparticle coated with NO-releasing BNN6 and polydopamine (pDA). In response to ultrasound, these nanoparticles should generate both NO and direct current.
To test their approach, lead author Won Jong Kim and colleagues first investigated the nanoparticles’ ability to release NO. In response to 5 s of high-intensity focused ultrasound (HIFU), the nanoparticles instantaneously released NO. They also evaluated the piezoelectric behaviour using a patch-clamp set-up. While solvent without pDA-coated nanoparticles exhibited no current spikes, in the presence of the nanoparticles, distinctive current spikes were seen with intensities proportional to the ultrasound intensity.
DBS is hypothesized to electrically stimulate the nervous system by opening Ca2+ channels of nearby neurons and then accelerating neurotransmitter release at the synapse. To investigate whether nanoparticle-generated current could provide similar neural stimulation, the team monitored the Ca2+ dynamics of neuron-like cells. Intracellular Ca2+ concentration significantly increased in cells receiving both nanoparticles and ultrasound, whereas either ultrasound or nanoparticles alone did not have any effect.
Cells treated with ultrasound-stimulated nanoparticles also generated an increased extracellular concentration of dopamine, indicating Ca2+ influx-mediated neurotransmitter release. Again, no significant change was seen with either ultrasound or nanoparticles alone. Tests using non-piezoelectric nanoparticles showed insignificant changes in Ca2+ influx and neurotransmitter release, indicating that these effects arise primarily in response to piezoelectric stimulation.
The researchers next performed a series of in vivo studies. To investigate NO-mediated BBB opening, they intravenously injected mice with NO-releasing piezoelectric nanoparticles and then applied HIFU to targeted brain sites under ultrasound guidance.
In vivo studies Mice received intravenous injections of nanoparticles, followed by HIFU. (Courtesy: Nat. Biomed. Eng. 10.1038/s41551-022-00965-4)
Two hours after injection, transmission electron microscopy revealed significantly higher amounts of nanoparticles accumulated inside the animals’ brains compared with control groups, demonstrating that the release of NO temporarily disrupted the tight junctions in the BBB. The researchers also showed that 2 h after HIFU application, the BBB was no longer permeable, confirming that the NO-mediated BBB disruption is only temporary.
Finally, the team evaluated the therapeutic effects of the nanoparticles using a mouse model of Parkinson’s disease. Mice were injected with nanoparticles followed by multiple applications of HIFU at the subthalamic nucleus (the US Food and Drug Administration-approved DBS targeting site) to restore dopamine levels in the brain.
DBS using the ultrasound-driven nanoparticles enhanced the animals’ behavioural functions, including motor coordination and locomotor activity. The mice showed a gradual improvement in motor function with daily HIFU stimulation for 10 days, with locomotor activity almost restored by day 16. The team surmise that the piezoelectric nanoparticles induced neurotransmitter release, which significantly alleviated the symptoms of Parkinson’s disease without causing any significant toxicity.
“We hope that ultrasound-responsive NO-releasing piezoelectric nanoparticles can be further developed into minimally invasive therapeutic approaches for the treatment of neurodegenerative diseases,” they conclude.
The group is now employing fundamental studies to determine out the underlying mechanisms for NO-mediated BBB opening. “We are also developing next-generation NO-modulatory materials to maximize their clinical usage while also minimizing their unwanted side effects,” explains first author Taejeong Kim.
The world is always in a state of flux – and no more so than now. Triggered in part by the COVID-19 pandemic, it’s clear that new technologies, such as telemedicine, digital payments and industrial automation, are moving faster than ever. We also need to find ways to decarbonize the economy, deal with an ageing population and harness the power of artificial intelligence.
In the light of these challenges, it’s vital that universities give students the right knowledge and skills so they can create and develop the next generation of technological solutions to tomorrow’s problems. With their unique combination of high-level scientific knowledge, numeracy and problem-solving skills, physicists are well placed to meet these needs in a wide range of hi-tech industries.
However, physicists often fall short on broader translational skills, such as effective communication, team working, creativity and the ability to find cross-disciplinary solutions to complex problems. Furthermore, traditional physics degrees often overlook the fact that many physicists do not end up in academic or physics-specific roles. Instead, they move into areas such as manufacturing, energy, finance and teaching, where they have to apply their knowledge in ways they have not been taught.
Ensuring enough physics graduates have the right mix of skills is a huge challenge for educators. It’s pleasing therefore that the Institute of Physics (IOP) revised its degree accreditation framework in 2022 to encourage universities to design more flexible physics degrees. Departments that want IOP accreditation now need to make translational skills more prominent, while placing an equal emphasis on knowledge and skills.
Future physicists To better prepare physics graduates, teaching methods need to change. (Courtesy: iStock/PeopleImages)
The new framework should ensure that physics graduates are better prepared for the world of work. It will give them “skills clusters” – combinations of translational and technical skills that are valued by graduate employers and can be used in many different careers. It will also encourage universities to teach and assess in innovative ways. Physicists heading into financial technology, cybersecurity or IT, for example, will need data-science and machine-learning skills alongside their core physics expertise.
We are also seeing the emergence of entirely new educational models that are challenging the traditional degree structure. Stanford University’s thought experiment Stanford2025, as well as UA92 in Manchester and 01 Founders in London, are all designed to attract students from more diverse backgrounds, and align more closely to employers’ needs. Rather than just being about what students learn, their focus is increasingly on how the students are taught and assessed.
But what would a physics degree look like if we were to start a new university or a new course entirely from scratch? How could we redesign physics courses to more closely match the skills that physics students and employers need? And what lessons can we learn from the way in which degrees were forced to adapt during the pandemic? Which changes were effective, and which were not?
Those were some of the issues that graduate recruiters and university physicists discussed during a series of IOP-supported webinars that took place in 2021. Organized by the UK’s South East Physics Network (SEPnet) and the White Rose Industrial Physics Academy (WRIPA), the webinars raised some fascinating issues that we summarize here. As the COVID-19 pandemic fades into the background, here are five important questions we need to ask ourselves if we are to create the physics degree of the future.
1. How do we teach students to tackle open-ended, unfamiliar problems?
Employers want graduates who can solve problems that are not necessarily well-posed or lie in a specific scientific area. However, those who recruit physicists often comment that candidates struggle with open-ended questions. This shortcoming may be due to the traditional “modular” nature of physics degrees, where each assessment only tests students on what they know about one particular topic.
No firm answer Physics students need to learn how to answer open-ended questions. (Courtesy: iStock/SeventyFour)
Take optics, for example. Students are often taught and assessed in terms of topics such as diffraction and interferometry, which means they only know how to solve questions framed in certain ways. It’s a method of teaching that reinforces “siloed thinking”, with students not realizing – or knowing – that optics is also hugely relevant to areas such as robotics, advanced driver-assistance systems and healthcare.
An alternative approach would be for students to be introduced to a number of topics at one time, with assessments based on all prior learning. This “programme-level” or “portfolio assessment” method could enable students to make new connections across different areas, and help them think more creatively about ways to solve unfamiliar problems.
Problem-based learning (PBL) programmes are already offered by a number of institutions, such as the University of Maastricht in the Netherlands, and the new coding college 01 Founders in the UK. Students here work in small groups to solve real-world problems that incorporate four key learning principles. They build knowledge from experiences rather than rote learning (“constructive education”), and apply knowledge and skill to societal challenges (“learning in a relevant context”). Meanwhile, “collective learning” and “self-directed education” mean students learn from peers and begin to manage their own education.
In terms of our future physics degree, a PBL programme could mean students taking part in one group project per term, during which they apply their learning to solve research or technical problems based on global challenges, possibly posed by businesses. Students would develop a variety of skills, such as project management, report writing, communicating and collaboration, as well as learning to think creatively in order to solve open-ended problems.
We also think that physics educators can learn from their colleagues in engineering. Far too often it’s assumed that physicists will stay in academia, with students striving to get top grades and universities reinforcing the idea that academic excellence is the only important measure of ability. In non-university roles, however, you need more than just academic ability to succeed.
Team work Some institutions offer group projects, where students work together to solve real-world problems. (Courtesy: iStock/franckreporter)
Engineers are much more aware of the realities of work. As well as using a variety of teaching methods that focus on the application of scientific principles, many engineering degrees do a far better job at engaging with industry and preparing their students for a variety of careers. We need much greater industry input into our future physics degrees to ensure we equip graduates with the skills that businesses need.
2. How do we account for students’ different learning styles?
The favoured method for teaching in universities, particularly in pure sciences, has long been the traditional lecture. However, the COVID-19 pandemic forced departments to try different approaches, including online sessions. It’s not been a smooth ride, with some undergraduates even having their tuition fees refunded because of complaints about the poor quality of tuition.
But there have been benefits. For example, some students seem more engaged and are more likely to ask questions in a chat box than they would if the lecture was face-to-face. Digital learning has also helped those with some disabilities or who face long commutes. What’s more, because online lectures are typically recorded with notes, the ability to return to recorded material later can be beneficial for reinforcing learning.
However, an over-reliance on online and recorded material can make it hard for students to choose and prioritize the resources they need. In addition, some students are not engaged by online learning, simply “switching off” during live sessions. Without face-to-face interaction, students lose the ability to interact with their peers and build their social skills.
The way that undergraduates study and learn has changed too. They rarely use textbooks, while libraries are now more valued as a space to study than somewhere to access learning materials. Tutorials have become more important for students to meet each other and staff in person. They are perfect for groups to work together to solve real-world problems, boosting their employability as well as their social skills.
But it’s not just about the students; academics are changing too. With staff and students returning to campus, academics have acknowledged the benefit of a hybrid form of teaching to engage more undergraduates. A tailored, “Netflix-type” offer featuring both in-person and virtual sessions could help meet a greater number of students’ individual learning needs and preferences to cover the same content.
3. How can we assess students on their ability to master challenges and apply their knowledge?
Traditionally, physics students were assessed through “closed-book” exams, where they sat in an exam hall for a fixed period of time and were tested on everything they know on one particular subject. But with the shift to online learning during the pandemic, educators have been forced to try new approaches to get a better understanding of a student’s ability and potential.
Continuous assessment, for example, has been introduced in some cases via regular online quizzes and “gamification” to measure progress and highlight gaps in understanding. It’s possible that, in the future, different online assessment methods (such as reflective journals, or patchwork assessment) could be used to assess the same academic content to suit students’ preferred learning style.
But should we go further? Why don’t we assess students based on their depth of learning (in other words, their ability to transfer and apply learning in different contexts) rather than on their ability to simply regurgitate information in order to progress to the next teaching level?
This alternative model of learning already exists in primary schools, where pupils of varying ages sit in different groups depending on their ability to accomplish certain tasks commensurate with a “mastery level”, rather than being separated according to age. Learners must demonstrate mastery in unit tests, typically achieving an 80% mark, before moving on to a new task. Mastery learning can be defined as a level of deep understanding about a topic that is maintained and can be recalled over time.
Mastering skills Primary-school pupils have to demonstrate mastery of a task before moving on to the next. (Courtesy: iStock/insta_photos)
In contrast, university students taking traditional “summative” tests typically need to get only 50% in their exams to move onto the next year of study. The problem with this approach is that students often end up with a superficial and shallow knowledge. What’s more, they often forget the information and are unable to apply it to different contexts. That’s no good for employers, who want graduates who can do more than just memorize facts and information.
If the model used at primary schools were adopted in a university setting, students would continue the cycle of studying and testing until the mastery criteria are met. Those who do not achieve this deeper level of understanding would be given extra support via, for example, tutoring, peer-assisted learning or small group discussions.
4. Can technology be used to enhance or replace laboratory work?
When it comes to experimental work, undergraduates are traditionally made to attend face-to-face lab sessions where they work their way through specific, well-known experiments. As well as developing practical skills, these timetabled hours give students structure to their working day, helping them plan and manage their time, and allow for group work and social interaction. However, the pandemic forced physics departments to reassess this approach almost overnight, and rapidly refashion experiments for an online world.
Some better-resourced universities were able to provide students with individual kits while others relied on video demonstrations. One department (which wishes to remain anonymous) offered some of their undergraduates socially-distanced, face-to-face lab sessions while others took part in virtual lab work online. This approach, while resource-intensive and challenging, did provide interesting results.
The assumption had been that students working online would have a less valuable experience than those in the lab. It turned out, however, that those very same students enjoyed working on their own – particularly as they could still interact with others to exchange ideas via chat forums. As a result, this department decided to continue with this approach to digital lab teaching.
Online laboratories Since COVID-19, virtual experiments have become more commonplace. (Courtesy: iStock/Alina-Vasylieva)
For some students with particular learning styles or needs, virtual labs are simply more effective. The Open University – which makes its students do experiments virtually through the OpenSTEM Labs interface – has also found that this method lets students learn from their mistakes. At in-person teaching labs, there’s often no time to make errors or repeat experiments as you would do in real research. Virtual platforms offer that flexibility and provide feedback about mistakes via a live feed.
For a future physics degree, a hybrid approach – with a mix of virtual and in-person experiments – seems essential. Students could, for example, go online to plan their experiments ahead of a class so that their time in the lab is more focused and involves more group work. They’d gain from the practical and social benefits of the real-lab experience, while also improving their independent learning.
Reduced time in the lab would also be cheaper for universities and free up vital lab space for other activities. We know that physics is an expensive degree course and the inclusion of high-quality virtual experiments, especially towards the start of a physics degree, could be vital in showing a university is ahead of the curve compared to others.
5. How do you attract and support a diverse community of students and staff in physics?
Most businesses understand that a diverse and inclusive workforce can lead to better ideas, decision-making and success. They realize the importance of reaching a wider talent pool to attract the best graduates, and of reviewing their recruitment processes and working environments to ensure they are more inclusive.
Universities need to do the same. Higher education is ultra-competitive, with degree courses increasingly measured and evaluated on the success of graduate employment and student satisfaction ratings. Universities need to ensure they provide a truly inclusive environment to better attract and support talented students from all backgrounds, and enable them to meet their full potential.
Specifically, universities need to do more for under-represented groups, including people with disabilities, those from minority communities and those from lower socio-economic backgrounds. Indeed, students with social communication difficulties, including autism spectrum disorder, have been found by the UK’s Association of Graduate Careers Advisory Services to be the least likely of all disability groups to be in full-time employment and the most likely to be unemployed. This is of particular concern for physicists because data suggests that students with social or communication impairment are more commonly found in physics programmes than any other undergraduate subject.
So what can we do to support university students with disabilities and learning needs? While school pupils are typically given an education, health and care plan (EHCP), undergraduates are not universally evaluated in this way. And even when information about a student’s disability or learning needs is given to a university, it is often not shared with teaching staff and departments because of concerns with confidentiality.
Staff therefore need to be trained so that they can spot problems, and point undergraduates to relevant help and support. We also need to find ways to share information about students’ learning needs when they enrol at university, while encouraging the students themselves to declare any disabilities they have.
Inclusive support A lecturer helps students – including those with disabilities – to work together in a lab. (Courtesy: iStock/FG-Trade)
Physics degrees also need to do a lot more to attract students from diverse backgrounds by widening access opportunities to attract the best talent. There has been some progress, with most physics departments already having well-established Equality, Diversity & Inclusion (EDI) committees and policies. However, we need to make sure that staff themselves are from a wide range of backgrounds too. They act as role models and mentors, and it’s important staff take part in EDI initiatives. But we must avoid making those who are from under-represented groups themselves shoulder all the responsibility for solving diversity issues. Empowering more staff to be accountable for diversity issues means the work isn’t dumped on just a few but is shared by many people.
So what does a physics degree of the future offer?
With the changing job market, growth of digital technology and greater awareness of diversity issues, physics degrees need to evolve.
Employers increasingly want graduates with good team work and problem solving skills, and it is possible to provide these via academically rigorous physics degrees. In fact, businesses do not want physics degrees to be “dumbed down” in any way. Instead, educators need to consider how these skills can be embedded within the curriculum so as to prepare students to better apply their knowledge at work.
Furthermore, across the higher education sector, new ways of teaching and different university models are being set up to attract and meet the needs of all students. These new approaches to curriculum design – along with changes to the IOP accreditation process – offer ideas about how the physics degree can evolve to equip every student with the skills and knowledge needed for future employment markets.
This webinar will demonstrate planning tools available for the Gamma Knife, such as inverse optimization, which can be used to improve plan consistency and quality and, remote access that allow users to contribute and explore plans from any location.
