Principles of Epidemiology in Public Health Practice

Epidemiology textbook

How to you become a disease detective and investigate outbreaks of infectious diseases? How do you discover an outbreak, collect data during an outbreak and use the data to identify the culprit, treat the patients and stop the outbreak? How do you solve practical matters as a disease detective?

What different kinds of epidemiological data exists and how can they be summarized? How do you measure risk? What is the difference between relative risks and odds ratios? What is an epidemiological association? What does it mean, and perhaps more importantly, what does it not mean? How do you visualize obtain epidemiological data? How can you even measure the impact of public health measures?

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Six Classical Genetics Papers on DNA

Crucial historical papers in genetics

How was the structure of DNA discovered? James Watson and Francis Crick is often given the sole credit for this, but the story is much more complicated. What insights did X-ray data and chemical considerations provide into this historical discovery?

How did scientists come to the conclusion that it was DNA and not proteins that were the material basis for inheritance? These and many other questions is covered in a Nature collection of crucial historical papers in genetics that was published in celebration of the 50th anniversary of the discovery of the structure of the DNA double helix in 1953.

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Eight HIV/AIDS Fact Sheets by National Institutes of Health

HIV/AIDS Fact Sheet

What are the different ways that HIV can be transmitted? How can you protect yourself? What are the different stages of HIV infection and how can the virus hide? What medications are available against HIV and when should a person with HIV start it? What does drug resistance mean in the context of HIV medication? Why is it important to adhere to HIV treatments?

What is the latest information on HIV clinical trials and HIV vaccine research? What does pre- and post prophylaxis mean? What opportunistic infections should people with HIV look out for? How can transmission of HIV between mother and child be prevented? What are some possible side effects of HIV?

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Astronomy Textbook With Stunning Illustrations

Astronomy textbook

What is the difference between an asteroid and a comet? How does the environment on Venus and Mars differ from Earth? How do you determine the mass and distance of starts in other galaxies? What happens when stars grow old? Why and how do neutron stars and black holes form? Why do some planets have rings, while others do not? How do moons form around plants?Why are some planets solid and others largely made of gaseous substances?

What does the Big Bang model actually state? How does space and time work in general relativity? How has general relativity been tested, and what practical applications does it have? What are the different types and properties of galaxies? How do galaxies change over time? What is the cosmic microwave background radiation? Is there life in other places in the universe?

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Essentials of Cell Biology Textbook

Essentials of Cell Biology

“Mitochondria are the powerhouse of the cell” is a phrase that is commonly thrown around on social media websites and websites that share memes. But what does it really mean? Where did mitochondria come from and how do they work in more detail? What is the difference between mitochondria and chloroplasts, and do plants also have mitochondria?

What receptors do cells use to detect their surroundings and how do they work mechanistically? What changes occur in cells that develop into cancer? What is the difference between transcript and translation? How can DNA contain so many bases, yet be so tightly packed? What happens during the different steps of the cell cycle?

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The Robbers Cave Social Psychology Experiment

Robbers Cave

Seeking community with people is common throughout the world and the history of humans. People who join groups allow them to flourish and avoid harmful physical and psychological consequences of being alone. Yet in our modern era, groups have also formed around things that are much more loose and not tied to direct survival, such as sports teams, countries and so on. Yet the same kind of cognitive and social mechanisms can operate in these groups as well and this can bring with it both positive and negative consequences.

What happens if you get a bunch of people together in an experiment and create artificial groups based on completely arbitrary criteria and subject them to resource limitations? Will preference for in-group members and hostility towards the out-group develop rapidly? By what mechanism does this happen, and are there ways to reduce friction between competing groups?

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Particle Physics and Inflationary Cosmology Textbook

inflationary cosmology

In the past, many different forces of nature (such as the strong force, the weak force and electromagnetism) were unified. This all changes with a process called spontaneous symmetry breaking. Attempts to unify these three with gravitation has turned out to be much more complicated and harder to complete. Developments in these fields have been highly fruitful, from getting a fuller understanding the interplay of different particles at very high energies to probing the secrets of superdense matter.

Cosmology reveals profound insights into the structure and history of the universe. Far from being at the center of the universe, humans live on one of billion planets and our sun is just one of many billion stars. The universe has been around for 13.8 billion years and was much warmer, denser and smaller in the past. Since then, it has expanded substantially. Physicists have discovered that the universe expanded exponentially in the deep past in a process known as cosmological inflation.

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The Legacy of Past Pandemics

Past pandemics

There have been many deadly pandemics that have had severe effects on human populations such as malaria, cholera, plague, and HIV. Some human genetic variants are associated with protection against these diseases, whereas others are associated with vulnerability to them. Because they have had such an influence on a population level, these pandemics have influenced human genetic variation through evolution.

Protective alleles are more common in areas that have been ravaged by certain diseases than in other areas. Yet, not all beneficial alleles have reached fixation in the population and not all vulnerability alleles have been eliminated. Basic evolutionary considerations can explain these observations.

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Running UNIX Commands from Python

Python code

Sometimes, you need to combine several scripts and programming languages in order to complete a task. This can be because different systems are communicating with each other or that the resulting program is easier for the user. Analysis of large-scale scientific datasets in physics, chemistry and biology often involve the user of high-throughput data generation and supercomputers. These supercomputers often run some kind of UNIX operating systems, whereas the data analysis often involve the use of Python, Perl, C++ and R.

This kind of scientific analysis of empirical data often involve different programming languages, core UNIX programs and custom scripts. Very often, these all have to interact in larger analysis pipelines that are run automatically from start to finish. This tutorial will demonstrate how to run UNIX commands from inside a Python script. This enables productive collaboration between Python, staple UNIX tools and specialized scientific software. In particular, special focus will be on how to use UNIX pipes in Python in the context of bioinformatics pipelines for analysis of biological data.

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Gravitational Waves and Binary Black Hole Merger

LIGO paper

General relativity is an improved model compared with Newtonian mechanics that works much better than the latter when dealing with high velocities and large masses. It often comes up in connection with black holes, GPS and movement close to the speed of light. In general relativity, seemingly weird things can happen that we are not used to on the scale of humans, such as tid moving slower in some areas or some objects being shorter depending on their speed. One of the core principles of general relativity is that the speed of light is the same in all frames of reference.

Einstein predicted the existence of gravitational waves in the early decades of the 20th century and researchers thought that these waves could be produced from cataclysmic events in space and that detecting them could provide substantial insight into these events.

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