squishyastrophage

documenting my PhD journey

[modern-austen]

some of my favourite microscope images I’ve taken

please don’t repost without credit

[squishyastrophage]

Sir Alec Jeffreys

1. Born in Oxford in 1950

2. Realised that every individual having a unique DNA profile can be useful in criminal cases

3. Discovered DNA fingerprinting on 10th September 1984

4. Knighted in 1994

He said that “[DNA fingerprinting] is the most powerful criminal investigation tool there is”.

[squishyastrophage]

Histology basics - epithelium

This semester, I’m taking a class on histopathology, which involves looking at tissues from the human body under the microscope and diagnosing any diseases/ pathology related to that tissue or organ. I studied histology (observing normal tissue under the microscope) last year so this is a more advanced subject, and can be useful in forensic science, especially for forensic pathologists (& sometimes forensic microbiologists - to see if there are any pathogenic organisms present). 

In this post, I’ll be writing about one of the first things you learn in histology, which can help in the identification of the tissue site - epithelium. Epithelial tissues surround cells, tissues, organs, etc. and the kinds of epithelia present depend on their location in the body. 

There are 3 main types of epithelium - squamous, cuboidal and columnar. There is a fourth one (transitional epithelium) which only occurs in the urinary bladder, and so, seeing that under the microscope can be a bit of a giveaway as to what you’re looking at. 

(image from Wikipedia)

The words simple, stratified and pseudostratified (mentioned in the diagram) just refers to their appearance, specifically, the number of layers there are. Simple epithelia have one layer that cover the tissue site they’re located in while stratified epithelia have several layers and pseudostratified columnar epithelia appear to be stratified but only really have one layer if you look closely. 

Their locations in the human body:

1. Simple squamous epithelium: mesothelium & endothelium

2. Stratified squamous epithelium: 

Keratinised - skin

Non-keratinised - oral cavity, vagina, cornea, oesophagus

3. Simple cuboidal epithelium: excretory ducts, some kidney tubules and germinal epithelium of ovary.

4. Stratified cuboidal epithelium (rare): some parts of excretory ducts.

5. Simple columnar epithelium: 

With kinocilia - respiratory tract

Without kinocilia - gall bladder and the GIT.

6. Stratified columnar epithelium (rare): some parts of the male & female urethra and the conjunctival fornix. 

7. Pseudostratified columnar epithelium: 

With kinocilia - respiratory tract

Without kinocilia (rare) - some parts of glandular ducts

With stereocilia - epididymis and vas deferens

8. Transitional epithelium: urinary bladder

As I continue with this semester, I’ll expand on this and write more about histopathology, which is more relevant to forensic science. However, it’s always good to know the basics. 

- V - 

[squishyastrophage]

ways to express creativity as a scientist

Being a science student isn’t all about memorising facts and following the steps of experiments. In fact, the most well known scientists made valuable discoveries by engaging with their surroundings and looking beyond the words written in a textbook. 

This year, one of my main goals is to focus on expressing my creativity while learning about different branches of science. Since I only start my Master’s degree in September, I’ll have a lot of time on my hands and I want to ensure that I use it wisely. 

The past 3 years of my life have been some of the best, mostly because I fell in love with learning in a way that I had never done before. In high school, I was constantly pressured by competition and I was even more disappointed that friends weren’t willing to help each other because of fear that their ranks in certain subjects would go down.  

However, university left me with a completely different feeling. Everyone was friendly and pleased to share their knowledge. I hope that everyone gets the experience of learning in a similarly positive environment, but we also have the ability to create such an environment for ourselves. 

Here is a list of simple ways to express creativity while learning science:

1. Botanical illustrations - If you have any unused notebooks, use it as a nature journal. Go outside, observe any trees/leaves/flowers/etc. and draw them! You can use books or the internet to then find out the name of the plant species and keep a record of it for your own knowledge. 

2. Drawing in general - Draw anything that you observe, as science encompasses pretty much everything in the world! You can draw bugs, stars, people, beakers, organs in the body, etc. 

3. Blogging - Writing emails, reports, essays and notes are a part of our daily lives and so you can also be creative by starting a blog about what you study, creating a website and sharing your experiences. (It’s also a great way to expand your network and learn from other lovely people online)

4. Poetry - A way to challenge yourself is by choosing a word or topic relating to science and writing a poem about it. 

5. Exploring - Go outside, walk in nature and observe your surroundings. Visit museums, observatories, botanical gardens and libraries as they’re all great places to learn something new. You can also make it an eventful day out by going with people with similar interests!

These are really simple ways to be creative but also very rewarding, considering how much information you can absorb. You’re also more likely to remember these things as you’re learning out of pleasure and not purely for the sake of memorisation. 

I hope you found this post helpful and are motivated to try something new in 2019. Let me know if you’re also willing to take this challenge with me & update me on your progress!

[squishyastrophage]

Priority of evidence

At a crime scene, there are certain items of evidence that have to be collected quickly by the crime scene investigators. Here is the general order of evidence collection/documentation:

1. Transient evidence (e.g. scents, melting items, sounds) 

2. Fingerprints

3. Impression evidence (i.e. footmarks, other prints/impressions)

4. Flammable liquids

5. Biological evidence (e.g blood spatter, DNA, semen)

6. Other trace evidence

7. Macro-evidence (i.e. actual items at the scene such as phones, laptops, etc.)

[squishyastrophage]

Photos I took at the Natural History Museum in Berlin. 

Photo #1: Micro-plastics from a face peeling cream under a microscope.

Photo #2: Fossils of sea creatures