108. Solar Efficiency Record Broken, Lumber Grown in the Lab, Dissolving Pacemaker Improved

That‘s Cool News | A weekly breakdown of positive Science & Tech news.

Scientists just broke the record for the highest efficiency solar cell | Interesting Engineering (01:46)

• A team of researchers at the US Department of Energy's National Renewable Energy Laboratory (NREL) has created a solar cell with a record efficiency of 39.5 percent.
  • This is the highest efficiency solar cell of any type, measured using standard 1-sun conditions.
  • Under lighting conditions equivalent to that of the sun
• The solar cell was also tested for its potential in space, especially for powering communications satellites, which are powered by solar cells and require high cell efficiency.
  • Under such conditions, it has a 34.2 percent efficiency.
• Principal investigator Myles Steiner, talks on the new solar cell:
  • “The new cell is more efficient and has a simpler design that may be useful for a variety of new applications, such as highly area-constrained applications or low-radiation space applications."
• The novel solar cell is built on an architecture known as inverted metamorphic multijunction (IMM) cells.
  • gallium indium phosphide on top,
  • gallium arsenide in the center,
  • gallium indium arsenide on the bottom.
  • Has three components that generate electric current in response to light.
  • Each component is built with a different material:
• These materials specialize in various light wavelengths, this allows the cell to capture more energy from the whole light spectrum.
• The researchers created these “quantum wells” with the middle layer.
  • Represents the minimum energy that is required to excite an electron up to a state in the conduction band where it can participate in conduction
  • By sandwiching a conductive layer between two other materials with a wider band gap, they were able to get the electrons confined to two dimensions, which allowed the material to capture more light in return.
  • A band gap is the distance between the valence band of electrons and the conduction band.
• This solar cell's middle layer comprised up to 300 quantum wells, which greatly increased the total efficiency
• Before the novel cell can become widespread, the researchers will need to reduce the expenses and find potential new uses.

First Patient Injected With Experimental Cancer-Killing Virus in New Clinical Trial | Science Alert (07:18)

• An experimental cancer-killing virus has been administered to a human patient for the first time, with hopes the testing will ultimately reveal evidence of a new means of successfully fighting cancer tumors in people's bodies.
  • The drug candidate, called CF33-hNIS (aka Vaxinia)
• The drug is an oncolytic virus, which is a genetically modified virus designed to selectively infect and kill cancer cells while sparing healthy ones.
  • A modified smallpox virus
• Works by entering cells and duplicating itself.
  • Eventually, the infected cell bursts, releasing thousands of new virus particles that act as antigens, stimulating the immune system to attack nearby cancer cells.
• Previous research in animal models has shown the drug can harness the immune system in this way to hunt and destroy cancer cells, but up until now no testing has been done in humans.
  • The first phase of the trial focuses on the safety and tolerability of the drug.
• The intervention is expected to enroll 100 participants in total, each being an adult patient with metastatic or advanced solid tumors who has previously tried at least two prior lines of standard treatment.
  • These individuals will receive low doses of the experimental treatment via direct injection or intravenously.
• If early results are successful and CF33-hNIS is deemed safe and well tolerated, additional tests will investigate how the drug pairs with pembrolizumab, an existing antibody treatment already used in cancer immunotherapy.
• If the drug does turn out to be safe and well-tolerated, we could be looking at a powerful new tool for fighting tumors, and a game-changer.
• According to surgical oncologist Susanne Warner, said back in 2020 “Our oncolytic virus trains the immune system to target a specific cancer cell … Meaning if a similar cancer cell ever tries to regrow, the immune system will be ready and waiting to shut it down."

Scientists can now grow wood in a lab without cutting a single tree | Interesting Engineering (11:46)

• The market for wood-derived products stood at $631 billion in 2021, and despite all the efforts that environmentalists have been putting in to prevent deforestation activities, it is expected to cross the mark of $900 billion by 2026, according to the Wood Products Global Market 2022 Report.
• That’s a lot of trees being cut down, but what would happen if we could grow wood without cutting trees? Interesting question, that we may have to answer soon.
• A team of researchers at MIT claims that lab-grown timber can replace deforestation driving products made from real wood.
  • They have developed a technique using which timber can be produced in any shape and size, so you can create it in a lab without cutting a single tree.
• The researchers at MIT performed an experiment that gave stem cell-like properties to normal plant cells
  • Extracted cells from the leaves of a flowering plant called Common zinnia (Zinnia elegans)
  • Then they stored the cells in a liquid medium for a couple of days.
  • The researchers treated the plant cells with a gel-based medium enriched with nutrients and hormones.
  • After some time, the cells gave rise to new plant cells.
• The researchers during this process noticed that by changing the hormonal concentration in the gel medium, they could control the physical and mechanical properties of the newly grown cells.
• Lead researcher Ashley Beckwith explains the role of hormones in plant cell growth:
  • “In the human body, you have hormones that determine how your cells develop and how certain traits emerge. In the same way, by changing the hormone concentrations in the nutrient broth, the plant cells respond differently. Just by manipulating these tiny chemical quantities, we can elicit pretty dramatic changes in terms of the physical outcomes.”
• Beckwith and her team were also able to 3D print custom-designed structures out of the cells cultured in the gel using a 3D bioprinting method.
  • Does not generate any waste, unlike the current furniture-making process, which leads to the loss of about 30% of the total wood as waste
• For three months, the lab-printed plant material was incubated in the dark. Not only did the lab wood manage to survive, but also grow at a rate twice that of a regular tree.
• Senior author and scientist Luis Fernando Velásquez-García talks on the techniques future:
  • “Though still in its early days, this research demonstrates that lab-grown plant materials can be tuned to have specific characteristics, which could someday enable researchers to grow wood products with the exact features needed for a particular application.”

Dissolving pacemaker links up with wearables to better control the heart | New Atlas (17:42)

• Last year, scientists at Northwestern University announced a transient pacemaker that dissolves when no longer needed.
  • Now, they improved the device, and incorporated it into a linked suite of wearable sensors.
• The original implant:
  • The original implant was designed for people recovering from an injury or heart surgery, or who otherwise only require a pacemaker for a short amount of time.
  • Once they've recovered from their condition – within five to seven weeks – the pacemaker will have biodegraded and been harmlessly absorbed by their body.
  • Doesn't have to be wired to a separate battery, and is just 250 microns thick, and weighs less than half a gram.
  • Only one surgery is required
• Among the improvements in the new version:
  • Its ability to stretch as well as flex – thus allowing it to better conform to the surface of a beating heart.
  • Now releases an anti-inflammatory drug as it dissolves, in order to prevent foreign-body immune reactions.
  • Wirelessly communicates with four other soft-electronic devices, temporarily adhered to the skin on various parts of the patient's upper body.
• All of the collected data is wirelessly transmitted to a nearby internet-connected smartphone or tablet, allowing the patient's doctor to remotely monitor their condition.
  • Monitors blood oxygen levels,
  • Tissue oxygenation and blood vessel tone;
  • A respiratory module at the base of the throat, that monitors coughing and other respiratory activity;
  • A haptic feedback module worn anywhere on the body, which vibrates to alert the patient of malfunctions or other problems;
  • A cardiac module, located on the chest.
• Prof. John Rogers, who is leading the research, talks on the device:
  • “For temporary cardiac pacing, the system untethers patients from monitoring and stimulation apparatuses that keep them confined to a hospital setting … Instead, patients could recover in the comfort of their own homes while maintaining the peace of mind that comes with being remotely monitored by their physicians. This also would reduce the cost of health care and free up hospital beds for other patients."

New Research Shows ADHD Medication Doesn't Help Kids Learn | SciTechDaily (22:03)

• For decades, most doctors, parents, and teachers have believed that stimulant medications help children with attention deficit hyperactivity disorder (ADHD) learn.
  • Approximately 10 percent of children in the U.S. are diagnosed with ADHD.
  • Of those, more than 90 percent are prescribed stimulant medication as the main form of treatment in school settings.
• However, in the first study of its kind, scientists at the Center for Children and Families at Florida International University (FIU) found medication has no detectable impact on how much children with ADHD learn in the school classroom.
• William E. Pelham, Jr., senior author of the study, stated:
  • “Physicians and educators have held the belief that medication helps children with ADHD learn because they complete more seatwork and spend more time on-task when medicated … Unfortunately, we found that medication had no impact on learning of actual curriculum content.”
• Researchers evaluated 173 children between the ages of 7 and 12 with ADHD participating in the center’s Summer Treatment Program, a comprehensive eight-week summer camp program.
  • Children completed two consecutive phases of daily, 25-minute instruction in vocabulary and subject-area content in science and social studies.
  • Each child was randomized to be medicated with a sustained-release stimulant medication during either the first or second of the instructional phases, receiving a placebo during the other.
• Contrary to expectations, researchers found that children learned the same amount of science, social studies, and vocabulary content whether they were taking the medication or the placebo.
• While medication did not improve learning, the study showed that medication helped children complete more seatwork and improve their classroom behavior, as expected.
• In more detail, while taking medication, children completed 37 percent more arithmetic problems per minute and committed 53 percent fewer classroom rule violations per hour.
• Additionally, consistent with previous studies, researchers found that medication slightly helped to improve test scores when medication is taken on the day of a test, but not enough to boost most children’s grades.
  • Helped children increase on average 1.7 percentage points out of 100 on science and social studies tests.
• Pelham talks on this jump in society to medicate:
  • “Our research has found time and time again that behavioral intervention is best for children with ADHD because they, their teachers, and their parents learn skills and strategies that will help them succeed at school, at home and in relationships long-term … Medicating our children doesn’t solve the problem—it only takes away the symptoms temporarily. Instead, families should focus on behavioral interventions first and add medication only if needed.”
• Researchers note that the study was conducted in a controlled summer school-like environment and results may be different in a regular classroom setting.
  • They would like to replicate this study in a natural classroom environment using academic curricula over the duration of a school year to further evaluate the impact of medication on learning.