Principle: Ficoll is a hydrophilic polysaccharide solution with a density of approximately 1.077 g/mL that is layered beneath the blood sample and centrifuged. It is commonly used to separate blood components based on their density, resulting in three distinct layers after centrifugation: plasma (top), PBMCs (interface), and red blood cells (bottom). During centrifugation, cells experience a centrifugal force that causes them to migrate until they reach a region where their density equals that of the surrounding solution. Since red blood cells and granulocytes are denser than Ficoll, they pass through it and settle at the bottom. Plasma, which is the least dense, moves to the top, while PBMCs form a layer between the plasma and Ficoll. This layer is known as the buffy coat.

Information on the Centrifuge Used Swing-bucket centrifuges hang vertically at rest but swing horizontally during centrifugation. The tubes swing out perpendicular to the axis of rotation, allowing the centrifugal force to act directly down the length of the tube. This keeps the layers undisturbed and perfectly horizontal, making this type of centrifuge ideal for separating density layers. In contrast, fixed-angle rotor centrifuges hold the tubes at a constant angle relative to the axis of rotation. As a result, the centrifugal force acts at an angle, causing components to move diagonally and form pellets along the side and bottom of the tube. Thus, swing-bucket centrifuges are ideal for PBMC isolation.

Protocol

1. Dilute the blood based on its thickness (usually a 1:1 ratio of blood to saline).
2. Layer Ficoll (1:3 ratio of Ficoll to blood) into a 15 mL tube without mixing the two layers.
3. Centrifuge at 1500 rpm for 20 minutes.
4. Discard the plasma layer and collect the buffy coat into a new 15 mL tube.
5. Dilute with saline to a total volume of 10 mL.
6. Centrifuge for 10 minutes at 1500 rpm.
7. Discard the supernatant and resuspend the pellet in saline or DMEM.
8. Count the cells using crystal violet dye.

Principle: Leishman stain is a mixture of methylene blue dye (blue in colour) and eosin dye (pink in colour). Methylene blue is basic, while eosin dye is acidic. As a result, methylene blue binds to acidic components of the cell, such as nucleic acids in the nucleus, and to acidic granules present in certain cells. Eosin dye, on the other hand, binds to basic components of the cell, including cytoplasmic granules. When a stained blood smear is observed under a microscope, differences in the shape, size, and colour of the stained nuclei and cytoplasmic granules allow different types of blood cells to be identified.

Protocol:

1. Using fresh blood, make a smear on a clean, grease-free glass slide.
2. Place a drop of blood near one end of the slide.
3. Hold another slide at a 45° angle and place it just behind the drop.
4. Allow the blood to spread along the edge of the second slide, then move it smoothly across the first slide in one motion.
5. A thin smear of blood should form on the slide.
6. Allow the smear to air dry completely.
7. Dip the slide into a coupling jar containing Leishman’s stain for 2 minutes.
8. Remove the slide and dip it into another coupling jar containing distilled water for 1 minute.
9. Rinse briefly by dipping the slide again in distilled water and remove.
10. Clean the back of the slide and observe under the microscope using immersion oil at 100× magnification.

Characterizing cells:

• RBCs are pink throughout
• Neutrophils have a dark purple lobed nucleus
• Lymphocytes have a large dark purple nucleus that occupies most of the cell
• Monocytes have a kidney-shaped dark purple nucleus
• Eosinophils have pink granules
• Basophils have purple granules

Below is an image of my Leishman’s staining where a monocyte and numerous RBC are visible:

Basophils have purple granules In my sample, a monocyte is visible among numerous RBC.

Overview of the Immune System The immune system is a network of cells, tissues, organs, and proteins that protect the human body from pathogens, such as bacteria, viruses, and other microorganisms that cause disease. When a pathogen enters the body, it triggers an immune response. There are broadly two types of immune responses: innate and adaptive.

Innate immunity is present in every human from birth and is designed to eliminate pathogens in a non-specific or general manner. Since all pathogens are treated in the same way, this response is fast-acting and is considered the body’s first line of defense. Examples of innate immunity include the skin, mucous membranes, tears, stomach acid, saliva, and reflexes such as sneezing.

Adaptive immunity, on the other hand, is specific to the type of pathogen the body is trying to eliminate. Through active immunity, the body can also help prevent a second infection of the same type by remembering the specific pathogen that caused it. This response is carried out by specialized blood cells, including B and T lymphocytes.

Blood and Its Cellular Components Blood contains a plasma component, which is the yellow liquid portion of blood, and a cellular component. The cellular component includes red blood cells (erythrocytes), platelets, and white blood cells.

White blood cells can be further classified into granulocytes and agranulocytes, based on the presence or absence of granules in their cytoplasm. Granulocytes include neutrophils, eosinophils, and basophils. Agranulocytes include natural killer cells and lymphocytes, which consist of B cells and T cells.

Of these blood cells, granulocytes, B cells, T cells, and natural killer (NK) cells are crucial for immunity. In addition, cells such as dendritic cells and monocytes also play an important role in immune responses.

All blood cells are formed from cells called haemopoietic stem cells (HSCs). Stem cells are unspecialized cells that can replicate an unlimited number of times while also being able to differentiate into specialized cells of various types. HSCs are immature blood stem cells found in the bone marrow. They can differentiate into all types of blood cells and are therefore considered multipotent, meaning they can differentiate into a specific group of related cell types.

Although I usually prefer to cook and eat savoury food, on this particular morning, with a sudden burst of inspiration from a YouTube video, I decided to give my shot at making an apple pie. This is the recipe I referred to for the ingredients.

Not only was it my first time making an apple pie, it was also my first time making dough from scratch, which I found out very soon uses a lot more butter than I’d expected; at some point, it felt like there was more butter than flour in the food processor.

All hope was nearly lost in the first 10 minutes of cooking, as I seemingly poured far more cold water into my dough than what was prescribed in the video. Miraculously, the first layer of dough held its shape as I rolled it out and laid it across the glass dish (perhaps sparing me early so the recipe could punish me later, as you’ll see).

I put the other half of the dough (which would form the lattice) in the fridge as I painstakingly peeled, cored, and thinly sliced eight Granny Smith apples with some (very unhelpful) assistance from my brother.

Tasking my brother to layer the apples on top of the dough, I began to prepare a sugar-butter mixture that was meant to be poured over the apples and lattice top of the pie; little did I know, this mixture would be my dish’s undoing.

What happens when you boil sugar and butter in a pot and let it cool? It becomes toffee. What was meant to be a smooth, pourable mixture turned into a rock-like substance as I poured it over my pie. Instead of seeping through the cracks of the lattice and coating the apples, it lay on top of the dough in a pile of steaming goop.

Knowing there was no fixing it at this stage, I decided to just go ahead and bake it, adjusting the oven to focus heat from the bottom rods in hopes of preventing the caramel from burning.

After around an hour of cooking, the pie came out looking perfect, minus the toffee on top.

The crust was perfect (probably because it’s impossible to add so much butter and still mess up), and the apples finished with a perfect balance of sweetness and tartness. Despite the unintended outcome with the caramel, the overall taste of the dish was as good as any apple pie I’ve ever had.

Next time, I’ll add some cinnamon powder, buy a tub of vanilla ice cream to accompany it, and hopefully not overboil the sugar-butter mixture.

(Also, forgive the terrible camera quality of the photos. I promise, it is an apple pie, not a pizza.)

I was competing in the U17 category for Long Jump, 110m Hurdles, and Triple Jump. At 15, with only a week of experience in two of the three events (110m Hurdles and Triple Jump), my hopes for a medal rested entirely on Long Jump. Over the years, Long Jump had evolved into my forte - I would usually bag gold in intra-school events and had placed on the podium at every inter-school event I participated in. I hoped to replicate this success at the national level by winning ISSO, which would also guarantee my qualification for the School Games Federation of India (SGFI). Only the top two athletes would qualify, so even a podium finish wouldn’t be enough - the stakes were high.

On the first day of the event, my only scheduled event was the triple jump. Although the techniques required for long jump and triple jump differ significantly, at the inter-school level, skilled long jumpers could be expected to translate much of their prowess into triple jump, and vice versa. Consequently, my coach and I were confident that a top-two finish was possible, especially considering that, in my one week of training, I had already matched the distance of the previous edition’s third-place finisher. With adrenaline coursing through my veins, surely I would be able to contend for a qualifying position, right?

Turns out, it wasn’t so easy! Although I managed to make the top 8, I barely scraped a 4th place finish after a grueling six jumps that progressively sapped more of my energy - a harsh reminder that my lack of training efforts would come back to bite me. One cannot expect to waltz into a national-level tournament with practically no training and compete with conditioned athletes from around the country. My habit of showing up to training only a few days before a tournament, like I had numerous times for other inter-school events, was no longer tolerated. And so, I dejectedly trudged into my room that night, trying to mentally prepare myself for my next two events.

Fortunately, after a good night’s rest and a tasty breakfast, my spirits were sky-high again. It was time for my main event, long jump, followed soon after by hurdles. As I warmed up for my first event, I glanced at my competitors - most of them were taller or more muscular and were doing warm-ups I had never seen before. As I snacked on a banana, I cast away any form of worry from my mind. I know their type - the tall, bulky guys who look intimidating but have never done long jump before, usually pulled into it from another event due to their athletic build. They were no reason for concern.

I couldn’t have been further from the truth.

Once more, my flawed mindset, paired with my poor preparation, saw me crumble in the first stage of the event. I didn’t even make the top 8 in my best event. While the other athletes precisely measured their run-ups with measuring tapes, down to the centimeter, I lazily marked my run-up with a water bottle after striding a random number of steps. I convinced myself that everything they did was unnecessary, that I was sure to perform well. I failed to heed the warning that had been shoved in my face the day before, and I paid the price for it.

While I wallowed in my misery after a miserable talk with my coach, they announced that the hurdles events were beginning. By that point, I was completely out of focus - not knowing where to report for my event or what to expect of myself. What was the point of me being there? I staggered to the start line as my event began, wondering if I was even in the right age category. As I took my position, my bare knees and fingers touching the rough, hot track, I let everything go.

At that moment, I had no fear of winning or losing - I had come so far and experienced so much. Maybe if I let go of this expectation I held of myself, one where the only option was victory, then losing a race wouldn’t be so crushing. And if I no longer feared loss, I wouldn’t be so scared to try my hardest and admit to myself that it wasn’t enough. So I gave it my everything in that race. Although my body was tired from the long jump in the scalding sun only a few minutes earlier, my mind was certain that I would push until the very end.

You were probably expecting me to say that I won the 110m hurdles after that moment of inspiration! I finished in third place, just short of an SGFI qualification that would have propelled my athletics journey to an unprecedented level.

Although I didn’t leave Gurgaon with my initial goal of SGFI qualification, I came home with a shiny medal and a new determination engraved in my mind - to give it my all in everything (and to actually go to training consistently).

My portfolio for the committee (Empress Wu Crisis), Yao Chong, an official in the Court of Empress Wu Zetian, seemed slightly disadvantaged compared to the other portfolios that had been allocated due to his limited relevance to the agenda at hand. Despite my previous experiences in Model UN conferences, doubts about my ability lingered, along with the temptation to blame my allocation as an easy excuse for any setbacks, which dampened my confidence. However, with every speech I gave in committee, regardless of the number of times I stuttered or said “um…,” my confidence grew. By the final day, I was determined to give my best effort by delivering my closing speech and proposing my directive (a plan for executable action during a crisis in committee).

Although my directive ultimately failed to gather enough votes for several reasons, I was honoured to win Outstanding Delegate (2nd place). This recognition was not just a reward for loud speeches or intricate plans but reflected my ability to help a peripheral character turn into a focal point of the committee and, more importantly, to unite a factionalized group through compromise.

While, at the time, the certificate was all I could think about, looking back on my experience has made me deeply appreciate the opportunity to meet new people from around the world—the UK, Georgia, Greece, Hong Kong, and so many more. The memories I made with them, from laughing over the names of historical characters to answering the goofiest questions our Executive Board could come up with, will stay with me forever.

I would like to thank my parents and my teachers at Inventure Academy, who supported me throughout this journey, without whom this opportunity wouldn’t have been possible. An additional thanks to my cousins, Aria and Kavya, who sent me reading material on the historical context of Empress Wu Zetian.

Additional Information

• Committee Background Guide - The Council of Empress Wu Zetian - Crisis Committee. PDF - archived from the Oxford Global 2024 website.

• Committee Brief - The Council of Empress Wu Zetian. Image - archived from the Oxford Global 2024 website.

Here is a drive link with my feature (including an interview) on the MU20 Magazine: https://drive.google.com/file/d/18FkIGZKn5BVibljoCfP-bT4lqzgAar7S/view?usp=sharing

Introduction

After deliberating on our topic choice, my team of three and I settled on creating an index to predict wildfires in California. With these fires annually destroying around 5,000 acres (equivalent to roughly 3,800 football fields) and impacting thousands of lives, predicting them became vital. Crafting an index could fulfill competition criteria and offer a practical solution for minimizing damage to human lives.

Brief of Index

The Wildfire Index outlined these general properties:

• The three critical criteria are green vegetation fraction, land surface temperature, and drought index.
• Analyzed each of California’s 58 counties to assess wildfire risk.
• Gathered data on July 1st, 8th, 15th, 22nd, and August 1st, 8th, 15th, 22nd, 2023.
• Index values range from 0 to 1, with 1 indicating the highest potential wildfire risk.

Information on these criteria was sourced from JSTAR Mapper, which provides satellite imagery and data from the NOAA-20 satellite, an essential tool for climate monitoring.

These data collection dates align with the US summer season when wildfire risk is at its highest due to rising land temperatures that can ignite dry foliage and other combustible materials.

Criteria

• Land Surface Temperature: A high land surface temperature facilitates wildfire outbreaks. It dries out moist vegetation, increases the chances of dry matter catching fire on the ground, and promotes rapid fire spread. Fig. 1. Shows a sample of satellite data taken for the Land Surface Temperature.

• Green Vegetation Fraction: Green vegetation can act as fuel for wildfires, so high amounts of greenery, along with high land surface temperature, suggest a greater likelihood of wildfire outbreaks. Fig. 2 shows a sample of satellite data taken for the Green Vegetation Fraction.

• Drought Index: This criterion indicates an area’s dryness or moisture conditions. Regions with low humidity and high dryness are more prone to wildfire ignition and spread.

Due to certain limitations within the JSTAR Mapper, we couldn’t include the Drought Index as a criterion in our formula, so it wasn’t part of our final submission.

Formula

We collected the values for Land Surface Temperature from 271 to 343 Kelvin (K), while Green Vegetation Fraction data varied between 1 and 100 units. To ensure consistency within our index, we needed to normalize the data. This normalization process involved: Green Vegetation Fraction divided by 100 (Land Surface Temperature - 291) divided by (343 - 291)

With both criteria now standardized on a scale of 0 to 1, we can calculate the average between them. This allows us to determine the wildfire risk for the selected area.

Conclusion

Ultimately, our work suggested that Colusa County, CA, had the highest risk of wildfires, whereas Alpine County had the lowest. In the future, we aim to improve the accuracy of the index by including more criteria, such as the Drought Index, and giving each criterion a weightage based on the extent to which it can influence the chances of wildfires. We will also take satellite data from an increased range of dates, not just in the summer.

Bibliography

Wikipedia, https://gis.data.ca.gov/datasets/8713ced9b78a4abb97dc130a691a8695/explore. Accessed 11 May 2024.

Wikipedia, http://extension.okstate.edu/programs/fire-ecology/fire-effects-research-and-demonstration-sites/. Accessed 11 May 2024.

“JSTAR Mapper.” noaa/nesdis/star, http://www.star.nesdis.noaa.gov/mapper/. Accessed 11 May 2024.

“Relationship of forest fires with a land surface temperature and b rainfall.” ResearchGate, http://www.researchgate.net/figure/Relationship-of-forest-fires-with-a-land-surface-temperature-and-b-rainfall_fig5_362672167#. Accessed 11 May 2024.

Satellites are crucial to provide information on weather patterns and natural calamities, that improve weather forecasting, allow rapid evacuation incase of upcoming disasters and can dictate the movement of economically vital aviation and oil/gas transport vehicles.

Satellites provide a wide range of data for analysis, including sea and land surface temperatures, vegetation information, humidity, cloud properties and more. In turn, this can help predict and detect hurricanes, floods and fires with speed and ease, saving not only money from damage repairs, but also countless lives.

These satellites use a variety of “channels” (portions of the electromagnetic spectrum) for multiple different uses. Weather satellites are majorly known to use the following channels to aid in their collection of meteorological data.

• Infrared (IR) channels are important for meteorological observations as these channels detect thermal radiation emitted by Earth’s surface and atmosphere. They provide valuable insights into temperature distributions across different regions. For example, weather satellites use IR sensors to detect temperature variations associated with weather systems such as cyclones. By analyzing the thermal profiles of cyclone centers relative to surrounding cloud structures, meteorologists can assess cyclone intensity and track its movement accurately.

• Visible light channels capture imagery within the visible spectrum, allowing visual interpretation of Earth’s surface features and atmospheric phenomena. These images serve multiple purposes, from monitoring cloud patterns to tracking changes in land cover. Additionally, visible light data can reveal the presence of aerosols (small particles in the atmosphere) and atmospheric pollutants like smog, helping in assessment of air quality.

• Microwave sensors are utilized to measure moisture content in the atmosphere, providing essential data for humidity and precipitation (different forms of water release from clouds, including rain, snow, hail and sleet) assessments. These sensors operate within microwave frequencies, allowing them to ignore presence of clouds and measure atmospheric moisture levels accurately.

• Ultraviolet (UV) sensors contribute to ozone monitoring and atmospheric composition studies. By detecting UV radiation, weather satellites can monitor changes in ozone concentrations and atmospheric composition, essential for understanding climate dynamics and ozone layer depletion. This can contribute to mitigating problems like global warming.

Thus, satellites use a variety of sensors, specific to different parts of the electromagnetic spectrum, to gain data on climate and weather patterns and systems, aiding humans in living an easier and safer life.

A week ago, our house was left devoid of any person able to cook dinner for my brother and me. Rather than ordering fast food in, I hurried to the kitchen to find beautiful cuts of chicken breast lying serenely in the freezer. It seemed a shame to order from a restaurant and let the chicken go unused. Thus, my 2020 lockdown self came alive, and decided to cook some tasty chicken rolls, oozing with flavor. Fortunately, it only takes 30 minutes to cook, and is relatively healthy with high amounts of protein and minimal fat.

(I don’t have precise measurements for the recipe since it was a hastily prepared dinner, so feel free to estimate based on your judgment and preferences.)

Ingredients:

• Chicken breast (or any other boneless cuts)
• Capsicum
• Onion
• Soy Sauce
• Honey
• Garlic
• Sriracha (or any other hot sauce)
• Tortilla

Recipe:

• Soak the chicken breast in saline water for around 1-2 hours before you start cooking. [This makes the chicken breast more moist after cooking. Water moves from the saline solution into the chicken breast via osmosis (the movement of water molecules from an area of higher water molecule concentration, in the solution, to an area of lower water molecule concentration, in the chicken)].
• To prepare your marinade, combine soy sauce, honey and sriracha in an approximately 2:1:1 ratio. Add plenty of diced or minced garlic to the mixture. You can taste it and adjust the flavors to your liking, depending on whether you want it sweeter or more umami. The marinade should ideally be a bit more than enough to coat all of the chicken pieces you have added.
• Cut the chicken into thin strips, about the size of your pinky finger, and add it to the marinade [You want to ensure the chicken strips are small so the chicken has a larger surface area to absorb all the tasty marinade]. You can let the chicken swim in this mixture overnight if you wish, to ensure the chicken soaks up all of the flavor, but you can cook it immediately if you wish.
• Cut your onions and capsicum into thin strips, and in a pan (I used a grill pan), sautee them with salt and any other seasoning (chili powder, garlic powder etc), until brown. Set them aside
• To the same pan add a bit of olive oil and the marinated chicken. Let it sear at a high heat, turning occasionally until it develops a char (be careful not to overcook it, otherwise it will turn out dry and rubbery). [The honey in the marinate contains sugars, such as glucose, that caramelize, giving your chicken a beautiful char.]
• Warm your tortilla, add your chicken and vegetable mixture, and enjoy with a squeeze of lemon or your favorite condiment!