Professor Gert-Jan Gruter and Strong Durable Bio-Based Plastics

 

Gert-Jan Gruter is a professor at the University of Amsterdam and leads a team of researchers at the Industrial Sustainable Chemistry group. He is also the chief technology officer at Avantium, an organization which provides technologies for applications in energy chemicals and pharmaceuticals, which he worked at since 2003. He graduated with a Ph.D in chemistry from VU University Amsterdam. His current research is focused on producing fully bio-based rigid polyesters, but he has researched many other topics in the physical and organic chemistry fields.

Gruter's team recently developed a synthesis strategy to overcome the low reactivity of bio-based secondary diols and make polyesters that have very good mechanical and thermal properties. They also have high molecular weights making them ideal for durable bio-based plastics. In fact, the rigidity is the most crucial part to ensuring the success of these plastics. The plastics that were already available fell short at this point and their low reactivity made it very difficult to obtain long polymer chains. The team countered this by enhancing the ending steps on the process where the low reactivity inhibits the growth of the chains and allows for the higher weight materials to be produced. 

Winter Ground with Horses is the Worst

As the weather gets colder here in northeastern New York, the ground gets so muddy so quickly. While I was bringing horses in for practice for the equestrian team, I noticed when I stepped on the mud lightly I would slip but when I stepped on the mud with my full force I would sink in. Quickly, I realized this must be friction in action, though in the moment I was more annoyed than anything that I was slowly sinking into a muddy field.

When I stepped lightly and quickly on the ground, I applied less force to the ground and therefore the ground applied less normal force to me. As a result of this lack of normal force and the fact that mud is a very slippery and smooth surface, I would slip. However when I stepped harder in the mud, more normal force was applied and I was able to bypass the slippy mud and make contact with the stickier underlying mud. Of course this resulted in me getting pretty stuck and wondering if I would ever get out from this mess. Also wear rain boots when you go mud walking, mud is no joke.

Xiao Mi and the Time Crystal

 

Dr. Xiao Mi is a researcher working for Google who explores applications of intermediate-scale quantum processors based on superconducting qubits. He graduated from Cornell University with an Engineering Physics major and works as a professor at Princeton University. What this means is that he is looking into a type of computation that works with quantum mechanics, in this case a quantum computer, using superconducting quantum bits (that can reach high speeds and can also be in two places at once) who if harnessed correctly, can be used to create computers that work very fast.  In 2021, him and his team at Google with Stanford scientists collaborated to work on creating the Time Crystal for quantum computing.

The Time Crystal is a structure that can repeat in time infinitely without any input in energy. A physical crystal that we see, such as a diamond, consists of physical structures that repeat to create a pointed form, but a Time Crystal can flip between its different areas in space to come back to one structure without loosing any energy. What this means is that the team has created a new phase of matter which was previously thought of as impossible. With the time crystal, the team can test their quantum computers to continue to recognize and detect new phases of matter on its own, which will further the understanding of quantum physics. The team as of now could only recognize and view a few hundred cycles of the time crystal, but will continue to work to try and view it indefinitely. 

Sources:

https://news.stanford.edu/2021/11/30/time-crystal-quantum-computer/

Dr. Jigang Wang

 

Dr. Jigang Wang is a prominent researcher in his field and has recently been a large contributor to the field of spectroscopy and microscopy. Dr. Wang began his higher education by getting his Bachelors in Physics at Jilin University in China in 2000. He then went on to earn a masters and subsequent Phd in Electrical and Computer engineering at Rice University in 2002 and 2005, respectively. He is currently a Professor of Physics and Astronomy at Iowa State University. In addition to his teaching role, he is also the senior scientist at the company Ames Lab where some of his more prominent research has come from.

One of these new findings has been a result of his investigation of microscopy techniques at this company. More specifically, he has been investigating ultrafast microscopy techniques to aid in the identification of new and more efficient materials for use in the photovoltaic component of solar panels. To achieve this, he has been working on microscopy technology to detect light at the terahertz frequency. This frequency is between Infrared light and microwaves and is useful in developing photovoltaic materials. The wavelength of this light is around a millimeter, so in order to detect it Dr. Wang and his colleagues have developed a microscope sensor that is only 20 nanometers in radius. With the use of this sensor, they have identified the compound Methylammonium lead (MAPbI3) as a potential candidate for a new photovoltaic material that could replace the traditional silicon used today. Dr. Wang is one of the most prominent researchers in his field and his contributions have made great strides to both the development of microscopy tools and the development of new photovoltaic solar technologies. 

Bored with work? Try spinning!

The other day while I was waiting in my lab for our microscope laser to warm up I got bored so I ended up spinning around in one of the chairs. While I was doing this I realized that I was pulling my legs in and pushing them out as I spun. As I was doing this I was speeding up as pulled my legs in, and I was slowing down as I let my legs stick out again. Thinking back to what was happening it makes a fun connection with our angular momentum topic that we covered in class. 

As I pulled my legs in, I decreased my moment of inertia (I). In order for the conservation of angular momentum to hold true, my angular velocity would need to increase to compensate for this, which it did! In the opposite sense, when I let my legs stick out again my angular velocity decreased because I was increasing my moment of inertia. An interesting aspect about this though is that my kinetic energy was actually increasing as I pulled my legs in and my angular velocity increased. But where would the extra energy come from to raise the kinetic energy of my system? It comes from the work that I did when I pulled my legs inward, that would have to counteract the centripetal acceleration that would pull them outwards. Anyways, good luck during exam week everyone!

Chonghe Wang and Continuous Ultrasound

    

     Chonghe Wang is an engineer graduate student at MIT who has recently been heavily involved in the production and testing of ultrasound patches that allow for continuous imaging over longer periods of time. Before starting his Ph.D. at MIT, Chonghe received his undergraduate degree from UC San Diego studying nanoengineering. Upon completion he moved to Harvard University for a year to start his Ph.D. in Engineering Science. Now at MIT, a team of scientists including Wang are doing extensive study on how to perfect the image resolution and durability of an ultrasound patch. In order to achieve this, the team created the patch by pairing a "stretchy adhesive layer with a rigid array of transducers," Wang says. This method allows for the device to conform to the skin while the transducers maintain their relative locations which can generate an image with more clarity and precision. "The device's adhesive layer is made from two thin layers of elastomer that encapsulate a middle layer of solid hydrogel." This layer mimics what is found in the gel used in a traditional ultrasound and allows for the easy transmission of sound waves. However, unlike the ultrasound gel we are used to, MIT's is "elastic and stretchy" and prevents dehydration. The bottom layer is meant to stick to the skin. The entire sticker measures about 2 cm^2 across and 3 millimeters thick which is about the size of a postage stamp. This research can change the way many doctors utilize ultrasounds and provide a much more accurate and consistent look into the body's deep internal organs over a longer period of time.

https://www.sciencedaily.com/releases/2022/07/220728142925.htm

http://zhao.mit.edu/teams/chonghe-wang/

A Bus Full of Children or Gravity? - Elannah De La O

Back home in Sonoma County, California, everyone has heard of the myth surrounding Gravity Hill. The tale is that if you encounter a strip of road on Sonoma Mountain, place your car in neutral, and the souls of a bus full of children will push your car to the top. Although I have never gone up this hill myself, my aunt and her children have and swear in having children's handprints on the back of their car afterwards. In thinking of this hill in conversation with my sister, it made me wonder if there was a possibility to explain the physics behind this.

A video of Sonoma Mountain's Gravity Hill taken for SFGate

How does one see a hill inclining and roll forward on neutral? In this case, it is an optical illusion. As explained by Elizabeth Borneman, a small strip of road such as Gravity Hill is an optical illusion by obscuring someone's horizon line partially or fully, which will affect how they perceive what is up and down. Sarah Kirker draws for SFGate the image below:

Typically, we are the top of the image. Our line of sight goes in front of us where we can see and perceive what is up and what is down. If we are perpendicular to the horizon line and know so, we can perceive an upcoming hill that goes upwards. If we are perpendicular to a downhill slope without being able to see a horizon line as featured on the bottom, we will see a straight or less steep downhill slope as an incline instead. For some roads, there are lots of trees to cover the horizon line but in the case of Gravity Hill, you can still see the surrounding area fairly clearly. What can change someone's perception is also the trees that have grown in such a way to give off the illusion of growing "uphill" when actually being downhill, which makes this road even cooler as it does seem so realistic to the human eye as an uphill.

So how does physics play into this? Simply put, when the car is in a neutral position, it will continue to move forward due to gravity alone. For Gravity Hill, the slight downward slope is enough to make the car continue to roll forward even with factors such as the force of friction, drag, and normal force. Although this is fairly simple, it is interesting to see how impactful an optical illusion is in making one question the laws of physics!

Sources:

https://www.sfgate.com/local/article/I-went-to-the-most-confusing-road-in-the-Bay-Area-15631568.php

https://www.geographyrealm.com/what-are-gravity-hills/

Physics in Sports?

 

Alix Deymier: How Soda is Rotting Your Bones

 On Tuesday, I went to Dr. Alix Deymier's talk. Dr. Deymier is an assistant professor at the Biomedical Engineering at UConn's School of Medicine studying bone formation and its relationship to acidosis. Dr. Deymier has had an interesting career path. She wanted to study the material composition of Native American Art and what makes up unique pottery, but instead she was forced to study bone bio-mechanics at Northwestern. Having little to no background in biology, she spent her graduate career learning about X-ray diffraction in bone, including the relationship between collagen and minerals and outside factors that affect their structure and function. Ultimately, she chose bones over art.

Her research on acidosis is incredibly fascinating and admittedly terrifying. Her lab wanted to analyze the effects of chronic soda intake on bone health. The main reason why she wanted to look at these effects is that bones are a large bicarbonate sink. Bicarbonate formation plays a role in chronic kidney disease and in the Keto diet; and bicarbonate reacts with acid to form a buffer solution. She took a group of mice and fed them homemade soda comprised of ammonium chloride in aqueous solution with a sprinkling of sugar (this was done because you cannot legally use soda in the lab since its pH is too low). In only 24 hours of drinking the homemade brew, the mice's blood and urine pH had dropped, their bone mineral and bone carbonate content had dropped, fraction resistance had increased, but there were no cellular changes within the bone. This meant that the soda's acidity alone had reacted with the bones to remove carbonate ions from the bone and made them weaker. What's even more shocking is that the pH of her homemade soda is less acidic than that compared to normal soda (Pepsi and Coke had pH values of around 2.5)! I thought this study was incredibly fascinating because it was interesting to see the interactions between chemistry, physics, and biology. Physics comes into play with her research because she wanted to look at the physical properties of bone to see how it changes with the soda solution. I learned something very important from her talk: drink less soda!

Professor Bradley T. Christian - medical physics

Professor Bradley T. Christian is a professor of Medical Physics and Psychiatry and the Director of PET Physics at Waisman Brain Imaging Lab at the University of Wisconsin-Madison School of Medicine and Public Health. He received his B.S. in 1989 in physics at St. John’s University. He proceeded to get a M.S. in 1991 and his Ph.D. in 1994, both in Medical Physics at the University of Wisconsin-Madison. His current research focuses on using PET radiotracers to study brain chemistry. He focuses on Alzheimer's disease, and investigates brain pathways involving dopamine, serotonin, and other neurochemical systems.

Recently, Professor Christian used positron emission tomography to assess memory in patients with Down syndrome. He performed a variety of scans to identify a variety of markers in the brain such as Aβ and tau to figure out if the tau PET biomarker is related to early memory impairment. He found that tau was negatively associated with memory in Aβ+ groups but not in Aβ- groups.  This finding is similar to Alzheimer's disease where high tau indicated dementia in Down syndrome.

References:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8976157/pdf/DAD2-14-e12256.pdf

https://www.medphysics.wisc.edu/blog/staff/christian-bradley-t/

Angela Gronenborn

Angela Gronenborn

Image of Angela Gronenborn. (Gronenborn, 2021).

Background

        Angela M. Gronenborn is a biophysicist researching HIV pathogenesis as the Rosalind Franklin Chair at the University of Pittsburgh Medical Center, in addition to her role as a Distinguished Professor in the Department of Structural Biology. Dr. Gronenborn traces her roots far from Pittsburgh, to Cologne, Germany, where she completed her education from primary school to PhD. Prior to beginning her undergraduate studies in physics and biology at the University of Cologne, she intended to study mathematics but was dissuaded by both her father and her high school principal despite her excellence in the subject. Because she did not ultimately want to use a degree in mathematics to become a teacher, she would not have been able to earn a living as a mathematician due to her gender. After receiving her bachelor's degree in 1972, Gronenborn pursued a master's degree in chemistry, which she received in 1975. Her PhD studies focused on comparing coupling constants of aromatic N-oxides that were experimentally derived using 13C Nuclear Magnetic Resonance (NMR) spectroscopy to those calculated via quantum mechanics (Kramer, 2008).

        Dr. Gronenborn was accepted into a Postdoc program away from Cologne at the National Institute for Medical Research (NIMR) with the Medical Research Council located in London,  where she aimed to solve the structures of protein-DNA complexes using NMR. After completing her postdoc. Gronenborn was employed as a staff member until 1984, when she went back home to Germany and was employed as head of the biological NMR group at the Max Planck Institute for Biochemistry in Munich. Her NMR group followed her to the National Institute of Health's Division of Diabetes and Digestive and Kidney Diseases as the head of structural biology. From 2018-2019, Dr. Gronenborn assumed the position of President of the Biophysical Society, and has since continued with her work at the University of Pittsburgh through NIH funding at the Center for HIV Protein Interactions (Kramer, 2008). 

Research Focus

    Along with her group, Dr. Gronenborn has elucidated the structures of biologically important proteins, including transcription factors and associated complexes, along with chemokines, cytokines, and HIV-associated proteins. The Center for HIV Protein Interactions is tasked with discovering the mechanism behind HIV's hijacking of host cells for replication. She hopes to decode the interactions between HIV's interaction with human immune system cells through determining the molecular structures of viral proteins. Hopefully, these structures will assist in the development of drug targets for HIV and reduce HIV's danger to the human immune system. Using NMR, researchers are allowed insight into how proteins interact to changes in their environment. The current approach of HIV drugs targets single proteins created by the virus, but newer methods focus on uncovering the structures of complexes that two or more virus-created proteins form to discover sites where protein interactions occur, as these sites are vulnerable and useful for drug targeting. Using this method, HIV viral molecules could be prevented from replicating without harming human cells. Researchers hope to combine x-ray crystallography and NMR-related techniques using cryo-electron microscopy to discover the sites of complex interactions (Kramer, 2008; Phelan, 2020). 

References 

Gronenborn, A.M. (2021), Editor Profile: Angela Gronenborn. FEBS J, 288: 4432-4434.                    https://doi.org/10.1111/febs.15889.

Kramer, D. (2008, February 1). Physics meets biology at new HIV structural biology centers. Physics Today. From https://physicstoday.scitation.org/doi/full/10.1063/1.2883903. 

Phelan, L. (2020, June 12). Angela M. Gronenborn. The Biophysical Society. From https://www.biophysics.org/profiles/angela-m-gronenborn.

 

Why do shoes have air bubbles?

Over thanksgiving break, I got new shoes. I noticed they have a funky design, with air holes in the bottom. I started to think to myself: what is the purpose of these strange holes? Is it aesthetic, or is it functional? 

Air bubbles in shoes have a unique history. A former aerospace engineer-turned-shoe designer Marion Franklin Rudy first incorporated air bubbles into Nike Air Max shoes in order to lessen impact when walking and allow more energy to go into running. Air bubbles are springy; the energy going from your foot into the ground is converted into spring energy, meaning you aren't losing all of it into the ground. That means you would be able to run faster by reducing work lost from your feet into the ground!  The technique used to install the holes is called blow rubber molding. Polyurethane is used to trap air bubbles inside the small plastic sole, and nitrogen is used as the air inside the bubble. The air pressure within the sole is around 25 PSI. So, they are functional AND stylish!

Although interesting, this applies to Nike shoes. What about the On Cloudrunners that have holes in the sole, not in polyurethane packets? On advertises that the shoe has "Zero-Gravity foam" which serves as a cushion for impact and for soft training. Cloudrunners also have moderate cushioning and are good for road usage. It serves the same function, but for a different shoe! It all comes to preference.

https://www.highsnobiety.com/p/nike-air-history/

https://www.asos.com/men/fashion-feed/2014_03_25-tues/facts-about-the-nike-air-max-bubble/

https://www.on-running.com/en-us/products/cloudrunner?specs=cloud

Real-life Object of Collision: Ice Skating Hazards and Not Anne Hathaway.

 At the time I came to the realization that physics exists as a field of study, I was probably around 5 years old and watching a Disney movie titled, Ice Princess (2005). In the movie, Casey is a teenage #womaninSTEM, who is tormented by the decision she needed to make in choosing between her passion and her education. The movie makes a point of highlighting Casey’s good grades and physics knowledge and how her mother really wants her to apply to Harvard. However, Casey was an angsty goody two-shoes, who also was good at figure skating, and for some reason could not both apply to Harvard and pursue figure skating. My physics-related memory of the movie is Casey speaking with her physics teacher and someone writing down physics formulas and free body diagrams on the chalkboard, which were then overlaid with videos of figure skating. I had solidly forgotten about the relationship between physics and figure skating and that movie for a good 15 years until I had the pleasure of being an object of collision several nights ago at an open skating event in the 1964 Arena. I had also really thought the main character was played by Anne Hathaway until I researched the movie for this article, which is disappointing finding to say the least.  

Although object #1 in the collision profusely apologized for skating into me while attempting to skate backwards without a rear view camera, I sincerely thanked object #1 for giving me a topic idea for my physics article on the relevance of physics in real life events. I plan to use this article to discuss how the skating collision relates to physics through the impulse and the conservation of momentum and energy, in addition to discussing the physics that makes ice skating possible. The collision began with I, object #2, skating at a very slow speed with my friend, who was dressed as a life-sized Hanukkah dreidel. Then, I felt something make contact with my back and push me forward slightly, watching as the other skater, object #1, moved at an angle away from me, at a decreased speed and angle of trajectory than I had initially seen them skating at. I am going to attempt to visually depict the event below. If the diagram is not adequate, please feel free to email me and we can recreate the scene at the next open skate event. I am not joking.

 

Summary of Collision Events

Before Collision

• Object #1 initially moving at velocity greater than object #2.

• Object #1 initial velocity direction was at an angle to the x-axis, assuming the axis is located in the direction of motion of object #2.

• Object #2 initial velocity near 0 m/s in direction perpendicular to the y-axis, at a 0° angle overlaying the x-axis. 

   

After Collision

• Object #1 moved with a slightly decreased magnitude of velocity, at an angle greater than the initial angle of velocity.

• Object #2 moved in the same angle as its initial velocity, with a magnitude of velocity greater than the initial. 

Figure 1. Diagram of collision. Figure represents position and change in direction of velocity before and after collision event by the two skaters. The initial velocity of object #1, labeled above, is of greater magnitude than that of object #2, and decreases after collision. The initial magnitude of velocity of object #2 is low, but increases after collision with object #1. The x-axis is overlaid with the direction of velocity of object #2, while the direction of velocity of object 1 is represented by the orange velocity arrows, accompanied by a green indication of angle. Initial and final velocities and positions are represented by the labels, " v " and " v’ ", respectively, with object #1 being orange, and object #2 being red. My apologies if you are color blind. The same color scheme follows for position, as is indicated on the x-axis with initial position being “ x ” and final position being represented at “ x ‘ “. 

 

Impulse and Conservation of Momentum

Momentum	Conservation of Momentum for Elastic Collisions	Impulse
p = mv	Δp = 0 p0 = p’ m1v1sinθ1+ m2v2sinθ2= m1v1’sin θ1’+ m2v2’sin θ2’	I=Δp  I = FAvgΔt

        In an elastic collision, with no external forces applied, both energy and momentum are conserved as objects bounce off of each other. Our collision was likely elastic because we did not continue to move together at a new shared velocity after the collision, but object #1 was deflected away from me, object #2, because the initial velocity of object #1 was at an angle compared to my direction of velocity. I was pushed forward slightly due to the force applied to object #2 by object #1 upon impact. The inverse relationship between average force (FAvg) and change in time (Δt) can be seen in the formula for impact (I): I = FAvgΔt. Additionally, because we were ice skating, there is external force from friction interfering with the possibility of a perfectly elastic collision, but very little, as the coefficient of friction between ice skates and ice is between 0.006 and 0.016 (Lozowski et al., 2013). For comparison, a surface considered to be slip-resistant has a coefficient of friction ranging from 0.2 to 0.29 (Mohamed et al., 2011). 

 

        The force exerted on object #1 when colliding with object #2 was small enough to allow object #1 to continue motion at a different angle with only a magnitude of velocity slightly less than than object #1’s initial velocity. The small amount of force applied to object #2 during the collision was likely prolonged by the cushioning in the puffer jacket on object #1, and the hoodie on object #2, resulting in a decreased magnitude of force of impact in the collision (FAvg), due to an increase in change in time (Δt) during contact. In addition, the angle of approach of object 1 was altered because collision with object 2 interfered with the path of object 1.   

      

Conservation of Energy

Conservation of Energy

ΔKE0 + ΔPE0 + WNC = ΔKE’ + ΔPE’ KE = 1/2mv2

       

Object #1 initially had greater kinetic energy before the collision than they did after the collision. Some of their kinetic energy was transferred to object #2 upon collision, where it was absorbed by the cushioning of clothing, or transferred to object #2 as potential energy, and immediately translated into a short increase in the magnitude of object #2’s velocity, while object #1 experienced a slight decrease in magnitude of velocity. Non-conservative work would have a small value on the part of friction, as ice has a very low coefficient of friction, as mentioned earlier. It is likely that the mass of object #2 was greater than object #1 because of the minimal change in position experienced by object #2 as compared to object #1. However, the mass and speed of each object are unknown, so cannot be used to calculate KE or momentum at this time.  

How Physics Allows For Ice Skating

Figure 2. Physics of ice skating. Figure originally published at (Physics of Ice Skating), https://www.real-world-physics-problems.com/physics-of-ice-skating.html. The figure presents the direction of the force vector as at an angle less than 90° to the direction of motion, although it is perpendicular to the direction the skate is facing. The angle of the skate from the direction of motion is represented by “a”, as this angle contributes to the acceleration that may be obtained, and the force vector is represented by “F”. 

 

            Ice has a low coefficient of friction in contact with ice skates because there is a layer of liquid water on top of the ice, which reduces the force of friction between the ice and the blade of the skate. In addition, the metal blade is a great conductor of heat, so that any friction that does result from skating generates heat which melts the ice into liquid, allowing for ease of skating. You can brake or speed up when ice skating due to the force applied from the edge of the blade on the ice in a perpendicular direction, allowing for the skater to push off of the ice and accelerate. Often, people skate with the hind leg pushing off of the ice to form enough friction to accelerate, and then switch to the other leg and do the same. Skaters have the option to  increase the angle between the blade and where it is in perpendicular contact with the ice, providing even greater potential for acceleration (Physics of Ice Skating). 

References

Cabot, M., & Davis, H. (2005). Ice Princess [Film]. Walt Disney Pictures.

Lozowski, E., Szilder, K., & Maw, S. (2013). A model of ice friction for a speed skate blade. Sports Engineering, 16(4), 239–253. 

Mohamed, M.K. & Samy, Abdelhalim & Ali, W.Y. (2011). Friction Coefficient of Rubber Shoe Soles Sliding Against Ceramic Flooring. KGK Kautschuk Gummi Kunststoffe, 64, 44-49.

Physics of ice skating. Real World Physics Problems. From https://www.real-world-physics-problems.com/physics-of-ice-skating.html

Why Do Pro Soccer Fields Have Wet Grass Over Dry Grass? by Andrew Cooke

If you have been living under a rock then you may not know that the World Cup is currently going on in Qatar right now. The World Cup is the most popular soccer tournament in the world where 32 of the best national teams compete to see who is the best, and it is held only once every 4 years. If you have watched any of these games lately you’ll notice a common trend. The sprinkler system in the field will always spray the field with water before warms-up, kick off, and during halftime. You may think this seems excessive to keeping the field healthy and you would be right, the sprinklers have no use on the health of the grass but instead on how the players like the game to be played. Any soccer player will tell you that a damp, not overly wet, field is the best to play on because of the speed that the ball travels across the grass. It’s fast, consistent, and keeps the spin that is applied to the pass across the ground. This makes for a better soccer game but how does the wet grass do this?

The answer is because the wet grass has less friction compared to dry grass, which can allow the ball to travel faster and do all these other things, but how is this possible from a basic physics level? So on a microscopic level, friction occurs because of irregularities between 2 materials. These irregularities can interlock with each other and cause a resistive force in the opposite direction of the object that is moving or having force applied to it. This is the basis of what causes friction force. When looking at a soccer ball on grass, there are irregularities in the ball and each individual grass it touches which slows the linear and centripetal velocities of the ball as it moves over them. Water, however, is liquid, and has no irregularities, so when it is on the grass/ball in small amounts it can fill in some of these irregularities and allow for less contact to occur. This means that the ball feels like friction force so the linear and centripetal velocities after it is kicked will decelerate at a low rate then if it was dry.

1. https://www.sciencedirect.com/topics/materials-science/lubricant#:~:text=Lubricant%20is%20widely%20used%20when,between%20the%20interfaces%20is%20reduced. 

2. https://www.semanticscholar.org/paper/Biomechanical-Analysis-%3A-Different-Phases-Of-Motion-Peter-Whiston/928e8e59c86265b47a80cb98e2fd95973ba2ba58 

Michal Zochowski by Andrew Cooke

Michal is a Biophysics professor from the University of Michigan and has been there for the last 15 years. Michal graduated from the University of Warsaw (in Poland) for his undergraduate, Masters, and PHD before coming to America to work at the University of Michigan. Michal is currently a Biophysics professor who specializes on the mechanisms of the formation of certain spatiotemporal patterns in select coupled systems, with special focus on their applicability during processing of information in the brain. To attempt to achieve this research Michal tries to connect the theoretical with experimental approaches. His group is focused on dynamic control and synchronization in those coupled systems as well as in complex computational systems. The couple systems they are especially interested in are self-adaptive ones that model neuromodulatory processes. Experimentally, the group he runs works on using optical imagery to view large neuromodulatory sections, and through this they can monitor activity spikes from individual neurons or as a large, averaged group of them. While this research is very complicated, it is unique in the way Michal combines physics, biology, and neuroscience in his overall research. 

Michals current research revolves around how the brain stores and processes long lasting information/memories and the importance that sleep has on that function. Synaptic plasticity is linked to the ability of the brain to take fleeting sensory information and store that as a long term memory/information. Using mice, Michal and his team will use newly found techniques and computational tools with recordings of the mice neural activity to find the effect of sleep-associated patterns in consolidating brain plasticity. The hypothesis being tested is that non-REM sleep plays a role in promoting plasticity between the LGN and the V1 (primary visual cortex) parts of the brain following the presentation of visual information. They will measure individual neuron changes in the LGN and V1 regions with the given stimulus and the given stimulus in the context of another (best way to put that I know it sounds kind of weird). They will then see if following this, the neurons that were selected and showed activity during the stimulus were used during the non-REM sleep to communicate between the LGN and V1 to increase plasticity. Overall this could be another massive piece of information proving how vital sleep is for our brains to communicate with themselves and learn from what we did during the day. 

1. https://lsa.umich.edu/physics/people/faculty/michalz.html 

2. https://lsa.umich.edu/physics/research/biological-physics.html 

https://braininitiative.nih.gov/funded-awards/thalamocortical-and-corticocortical-mechanisms-sleep-dependent-visual-learning

Dr. Peter Schlein → Particle Physicist and Grandfather by Alex Rosenberg

Instead of writing about a random physicist I discovered online, I decided to write about one of the most genius men I have ever met: my grandfather. I waited a long time to write this blog because I wasn’t exactly sure how to put it into words, but what better place is there to start than the beginning? Dr. Peter Eli Schlein, or “Papapa” as I called him, was born on November 18th, 1932 in Brooklyn, NYC.  Always having a love for science, he went to Union College for undergraduate studies where he fell in love with, and majored in, physics. He afterward studied at Northwestern University for a PhD in physics from 1954-1959, during which he did a year-long physics fellowship 1955 in Zurich, Switzerland (where he taught himself German!). And if you thought that wasn’t enough, he then worked as a postdoctoral researcher at the University of Chicago and then Johns Hopkins before becoming the youngest tenured professor at UCLA at the age of 29! Phew!

Anyway, moving away from his educational experience, Papapa was a nuclear particle physicist who was best known for his role in founding two important fields in nuclear physics: the partonic structure of the Pomeron and forward B-particle production. As his colleagues stated: “Had he not pursued it, much of the work in his field would probably not have been done or would have been undertaken at a much later date — and it would certainly have lacked his distinctive style.” In 1969, he went on sabbatical from UCLA to work at ISR CERN in Geneva, Switzerland (which happens to also be when my mom was born resulting in her growing up in Geneva while her father worked at CERN). In summary, I realize I am very biased but I truly do believe that my grandpa was one of the most intelligent physicists I have ever heard of. I wish I got to know him better in the first six years of my life, but the memories I have of him are some of the best I can remember.

Professor Maurice N Collins and New Research on Repairing Spinal Cord Tissue by Ellie Marotta

At the University of Limerick, a group of researchers led by Professor Maurice N Collins

are studying new ways to repair spinal cord tissue. Professor Collins is a senior lecturer at the

University of Limerick in Ireland. He leads an interdisciplinary research group, which includes

students studying chemistry, materials science, biology, pharmacy, and engineering. He is the

editor of the International Journal of Biological Macromolecules and is involved in many

nationally funded programs that focus on bioengineering. Professor Collins has a PhD in

Materials Science from the University of Limerick.

His research involves the development of new hybrid biomaterials and nanoparticles,

which are used to “promote repair and regeneration following spinal cord injury” (Healthworld).

Professor Collins developed a new hybrid biomaterial that is biologically compatible for spinal

repair. A spinal cord injury is very traumatic and serious; paralysis is often a result of a spinal

cord injury. By using tissue engineering, researchers are hoping to improve the quality of life for

people who suffer from spinal cord injuries.

https://health.economictimes.indiatimes.com/news/industry/researchers-demonstrate-new-metho

d-of-spinal-cord-tissue-repair/95884881

Tengfei Luo by Jessie Sulger

Tengfei Luo obtained his Bachelor of Science from Xi’an Jiaotong University in China with a major in Energy and Power Engineering, his PhD in Mechanic Engineering from Michigan State University, and his Postdoctoral Associate in Mechanical Engineering from MIT. Seongmin Kim obtained a PhD in Mechanical Engineering at Pohang University of Science and Technology. Tengfei Luo, now a Professor of Energy Studies at the University of Notre Dame, and Seongmin Kim, now a postdoctoral associate at the same institution, are developing a coating for transparent windows that can block heat from the sun from entering through a window. The coating, also known as transparent radioactive cooler (TRC) does not impact visible light, but it prevents heat producing light from permeating the window. This invention will help drastically reduce energy consumption, especially in the summer, when air conditioning and other cooling device use is at an all-time high. The TRC was developed using a computational model to test different combinations and orders of the materials being used. They finally settled on a coating consisting of silica, alumina, and titanium oxide on glass, topped with the polymer used in contact lenses.

 

 

References:

https://www.sciencedaily.com/releases/2022/11/221129165902.htm

https://monsterlab.nd.edu/people/tengfei-luo/

https://monsterlab.nd.edu/people/postdoctoral-associates/dr-seongmin-kim/

Physics of a Hold and Spin by Danielle McNerney

Over Thanksgiving break, my family and I went on a walk in the park. I came across the Hold-N-Spins on the playground and tried to think of how it could connect to what we have learned in class. The Hold-N-Spin is essentially a combination of a merry-go-round and monkey bars into one piece of equipment. It works by having you hold onto the bar and start running until you are ready to lift your feet off the ground. The Hold-N-Spin umbrella is on a slant which connects to our energy unit in class. At the top of the umbrella, the kid would have more potential energy and move at a slower angular velocity. As the kid is moving "uphill", he/she has a deceleration of 9.8 m/s because of gravity. Additionally, as the kid is moving "downhill", the potential energy transfers to kinetic energy, and the kid will start to move at a higher angular velocity because it will accelerate at 9.8 m/s. This makes the Hold-N-Spin more fun because of the changing speeds. 

Physics in Tug of War by Lucy Li

A recent browse of photo albums reminds me of the tug of war in my senior year at my high school. Unfortunately, our class lost during that game. At that time, we only thought that we didn’t have enough strong people and good strategies. But after this semester’s learning, it motivates me to take a deep analysis of tug of war based on physics. 

We usually believe that tug of war is about strength. However, after drawing the free body diagram, I realize that tug of war is not really about strength but about friction. If you don’t have enough friction, it doesn’t matter how strong you are because you will slide all the way. 

From the third Newton's law we know that if two objects interact, they apply forces to each other of equal magnitude and opposite direction. ​​Since the person pulls on the rope, the rope pulls on the person in the opposite direction. So if you were to increase your force on the rope to 2,000 Newtons,  the same rope pulls on both people. So how much force you apply is not the key point here. 

Each puller has basically four forces acting on them: tension from rope, friction from ground, weight, and normal frounce from ground. Two vertical forces get canceled. Therefore, if a puller wants to win, his friction force must outweigh the tension from rope. 

But it is still about mass!!

From previous learning, we know that friction force is equal to normal force x friction coefficient. With more mass, people will have more weight based on the equation of Fg = mg. The magnitude of normal force is equal to the magnitude of weight since the acceleration in vertical direction is zero. Therefore, with more mass, people will have greater normal force, resulting in greater friction force. Probably that is the reason why people want strong and heavy pullers to join the team. Meanwhile, strength may refer to great friction force here based on the explanation.