Discovery Lectures

Tuesday - Discovery Lecture Recap

“Through the Looking Glass: Chirality and Molecular Handedness”

Professor Tim Johnstone

During our second Discovery Lecture, Professor Johnstone introduced us to the world of molecular chemistry. He described chemistry as the science of transformation, explaining how the arrangement of atoms can completely change the properties of a substance.

To kick off the lecture, he showed us an experiment—igniting magnesium inside a block of dry ice. Instead of extinguishing the flame, the dry ice allowed the magnesium to continue burning brightly, producing magnesium oxide and elemental carbon. This experiment showed us how chemistry can often produce surprising transformations.

Then, Professor Johnstone introduced several fundamental concepts that help chemists understand molecular structure. He explained that elements tend to form a predictable number of chemical bonds, known as their valence—he also showed us scientists’ research from the 1800s (!) which illustrated early drawings of elements and their bonds. He also explained how molecules can share the same chemical formula while having entirely different structures, a phenomenon called isomerism. 

The lecture then focused on chirality, the idea that some molecules cannot be perfectly superimposed onto their mirror images. For example, our hands are chiral—although your left and right hands are mirror images of each other, when you put them on top of each other, they don’t match perfectly. These mirror-image pairs, called enantiomers, may contain the exact same atoms, yet their three-dimensional arrangement can lead to different chemical properties and biological effects. He then had a couple student volunteers hold giant balls and stick models of molecules to prove chirality, giving us the chance to experiment with different atomic structures to see the concept for ourselves.

Although some of the chemistry became increasingly complex, Professor Johnstone taught us how understanding the three-dimensional structure of molecules is essential in fields ranging from medicine, materials science, and more! 

By Clarina Manuel

Wednesday - Discovery Lecture Recap 

“Integrated photonics devices for biomedicine and astronomy”

Professor Holger Schmidt

On Wednesday, Professor Holger Schmidt introduced us to the field of integrated photonics and showed how light can be used to solve problems in both medicine and astronomy. 

Professor Schmidt first introduced the concept of optofluidics, which combines integrated optics with fluids such as blood, water, air, and chemicals. Instead of simply shining light through a sample, optofluidic devices use specially designed waveguides to control how light travels and interacts with particles inside a fluid. He explained that light naturally stays inside materials with a higher refractive index, which is why fiber optic cables can transport light over long distances. However, traditional capillaries pose a challenge because the surrounding material has a higher refractive index than the liquid inside, causing light to quickly escape. To solve this problem, researchers developed hollow-core waveguides, devices that keep light confined inside the liquid itself. As particles pass through the waveguide, they intersect with the light, producing tiny digital “blips” in the logs that allow scientists to detect a biomarker or RNA molecule.

Then, Professor Schmidt talked about the biomedical applications of this technology. He explained that a tool to detect viruses must be able to detect both extremely small and very large amounts of viral RNA, while also maintaining high specificity so that only the correct target molecules are identified. He then went into his research, which directly counts individual RNA molecules after they have been isolated using magnetic beads. He also introduced spectral multiplexing, a technique that uses different colors of light to simultaneously identify multiple diseases within the same sample.

Finally, Professor Schmidt showed how these same photonic technologies are being used in astronomy. By analyzing the wavelengths of light emitted from stars, scientists can determine the chemical composition of distant objects and even calculate how quickly a star is rotating by applying the Doppler effect. He also shared how machine learning can accurately predict spectral wavelengths and showed us new 3D-printed spectrometers that improve stability for astronomical observations.

At the end of his lecture, Professor Schmidt showed us images he and his research group captured using the waveguide-based spectrometer at the Lick Observatory—they were able to take a four-minute observation of the third-brightest star in the night sky and stars over 100,000 times dimmer than what the human eye can see!

We learned how one technology can be applied across completely different fields, from detecting viruses to observing distant stars.

By Clarina Manuel 

Thursday - Discovery Lecture Recap

“Sampling the ocean from the North Pole to Antarctica”

Professor Phoebe Lam

On Thursday, Professor Phoebe Lam introduced us to the life of a sea-going chemical oceanographer. Over the past decade, Professor Lam and her colleagues have spent 246 days at sea on four research expeditions stretching from the Arctic Ocean to Antarctica and through the Pacific. Along the way, she shared not only the incredible places she has visited, but also how scientists use chemistry to better understand the oceans.

Before describing her expeditions, Professor Lam taught us how to “think like a chemical oceanographer”- she explained that the distribution of chemicals in the ocean is controlled by two main processes: inputs and outputs at the ocean's interfaces (such as melting ice or the atmosphere) and internal cycling, where physical, chemical, and biological processes continually move around chemicals throughout the ocean.

Professor Lam first walked us through each of her research cruises and what questions they wanted to investigate. In the Arctic, her team studied the retreating of sea ice caused by polar amplification (which is the phenomenon in which Earth’s poles warm faster than the rest of the planet) and studied how melting ice changes the ocean's chemical composition. Then, as her research continued through the Pacific Ocean, she explored its many different biomes, from regions rich in algae to nutrient-poor “ocean deserts,” studying the chemical imprints left behind by various biological and physical processes. Most recently, her expedition to Antarctica focused on rapidly melting glaciers and the chemical consequences of all of that ice flowing into the ocean. These projects are all part of GEOTRACES, an international program in which scientists around the world work together to study the distribution of trace elements and isotopes throughout Earth’s oceans.

Then, Professor Lam talked about how chemical oceanographers actually collect their data. Because her team studies trace elements such as iron (which exists in incredibly small amounts in the Pacific—about the quantity of iron in one small paper clip!), even tiny amounts of contamination from a research ship (such as the rust from the metal bottom) can affect the results. To solve this problem, scientists use specialized equipment such as a CTD Rosette, which is not constructed with any iron-containing metal and collects clean seawater samples from different depths of the ocean. Her team also collects samples of aerosols, snow, sea ice, and ocean sediments before bringing everything back to UCSC for analysis using tools such as spectrometers, calorimeters, and even building-sized synchrotrons! Professor Lam explained that while collecting the samples may only take a few weeks at sea, analyzing them, interpreting the data, and publishing the results can take several years.

At the end of her lecture, Professor Lam showed us what a day in the life of a chemical oceanographer at sea was like! We got to see all the equipment she described earlier, as well as their ultra-clean labs (called “bubbles”) that are fully covered in plastic and use hepa filters for the air in order to prevent any contamination. She also showed us so many pictures of all the amazing landscapes/views and wildlife she got to see while out in nature (so many cute penguins!).

Overall, Professor Lam showed us how studying even the smallest amounts of chemicals in the ocean can help scientists put together various pieces of data and collaborate to answer much larger questions about Earth's oceans and climate.

By Clarina Manuel

Friday - Discovery Lecture Recap

“How to maintain an organ: Stem Cells & Cancer”

Professor Zhu Wang

During this week’s final Discovery Lecture, Professor Wang introduced us to the biology behind cancer development and the research his lab conducts to better understand prostate cancer. He explained that the idea of cancer as a disease caused by abnormal cells goes all the way back over a century, with scientist Theodor Boveri proposing in 1914 that “malignant tumours” result from changes within cells.

Then, he went into the concept of stem cells, which have two defining qualities: self-renewal, which is the ability to continuously produce more of themselves, and multipotency, the ability to develop into many different specialized cell types. His research focuses on the cell of origin model for cancer, which suggests that different types of cells can result in different forms of cancer. 

Professor Wang then explained to us his research, which is focused on prostate cancer. He described how researchers study the disease from its initiation to its progression and eventual metastasis. He explained that while some prostate cancers grow slowly enough to be monitored through just surveillance, more aggressive cases (such as gleason score) often require treatments such as androgen deprivation therapy or surgery. To better study them, his lab uses mouse models and several techniques to identify adult stem cells, including in vitro assays (which study the sphere/colony formation), transplantation assays, and genetic lineage tracing (which is when scientists label stem cells and track how they behave over time).

His team's research has proved that both basal and luminal cells can serve as the cell of origin for prostate cancer, but they found that tumors that begin from basal cells tend to progress more slowly. By understanding where cancer starts, Professor Wang hopes to improve how prostate cancer is diagnosed and treated in the future.

By Clarina Manuel