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The English Oak, Andrew Orr, Oil On Panel, 2017

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The English Oak, Andrew Orr, Oil On Panel, 2017 submitted by /u/musicAnts to r/Art
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clumma
1 day ago
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Is English Wikipedia’s ‘rise and decline’ typical?

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Is English Wikipedia’s ‘rise and decline’ typical? submitted by /u/pizzaiolo_ to r/wikipedia
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clumma
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Study Finds New Genetic Associations for Depression

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Scientists at the University of Edinburgh have identified more than a dozen new genetic variants associated with depression, offering more details of the influence genetics has on the condition, which affects more than 322 million people worldwide.

The study — funded by the science charity Wellcome Trust — was published in the journal Nature Communications and used data from more than 300,000 people that are part of the UK Biobank. Researchers identified almost 17 genetic variants associated with depression, and the findings were then replicated against data from a similar-sized dataset that consisted of 23andMe customers who consented to participate in research.

While twin studies have long shown a strong genetic influence for depression, pinpointing the genes and genetic variants involved has been elusive until only the last few years. Access to new and very large data sets is revealing genetic associations that could not be seen before in smaller studies.

“These new findings help us better understand the causes of depression and show how the UK Biobank study and big data research has helped advance mental health research,” said Professor Andrew McIntosh, Ph.D., of the University of Edinburgh’s Centre for Clinical Brain Sciences and the lead author of the study.

The UK Biobank data includes individuals with depression classified in three different categories: clinically diagnosed major depressive disorder, self-diagnosed “probable” major depressive disorder, and a third category defined as broad depression that may also include traits such as anxiety. The researchers found associations across all three categories and identified 17 genetic variants associated with depression. While a few of these variants have been identified in other studies to be associated with depression, 14 of the associations are new. Those genetic variants influenced genes involved in the function of synapses in the brain.

“This study identifies genes that potentially increase our risk of depression, adding to the evidence that it is partly a genetic disorder,” said David Howard, Ph.D., a co-lead author of the study and a Research Fellow at the University of Edinburgh’s Centre for Clinical Brain Sciences.  “The findings also provide new clues to the causes of depression and we hope it will narrow down the search for therapies that could help people living with the condition.”

Separate to this work, 23andMe has worked on other studies investigating depression. In 2016, along with Massachusetts General Hospital and Pfizer, we published findings in what was by far the largest study of its kind focused on major depressive disorder. In that study, researchers identified 15 new genetic regions linked to depression. And last year 23andMe launched a depression and bipolar disorder study, quickly enrolling 15,000 people with major depressive disorder. That work is ongoing, and we look forward to continuing to contribute to advances in depression research.

 

The post Study Finds New Genetic Associations for Depression appeared first on 23andMe Blog.

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clumma
6 days ago
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Crowdsource Treatments for Health Conditions

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Starting today, we’re providing an easy way for our customers to share and crowdsource treatments they use to manage common health conditions, like depression, asthma, ADHD and migraine.

 

All 23andMe Health + Ancestry service customers will be able to learn about the effectiveness and popularity of hundreds of different treatments for common conditions — and will also be able to contribute their own personal experiences. Crowdsourced treatment ratings are just one facet of our new Condition Pages, which contain database insights on 18 common health conditions.

 

Each condition page includes scientifically curated information describing the condition, its genetic and non-genetic influences, as well as how common it is in 23andMe research participants.


The treatment section summarizes what 23andMe customers with these conditions say works or does not work in treating their condition. This kind of crowd-sourced tool allows individuals with say, depression, to see what other customers say is effective or not effective in treating the condition. This offers people a different kind of information than they could get simply by doing a Google search, because it comes from others like them living with the same conditions.

Since rolling out the treatment pages over the past few weeks, thousands of people have already contributed over 30,000 personal reviews of their responses to different treatments. This is allowing people to build communities that share common conditions but have different strategies for dealing with them. At 23andMe, we believe in helping our customers manage their health — not just through genetic reports, but also by giving them access to lots of useful, relevant information.

“It’s evident by the growing response from our customers that there is a real desire for information around health treatments,” says Jessie Inchauspe, the product manager who spearheaded work on the treatment pages. “It’s important to enable people to actively engage in sharing health information with each other.”

This is the first time we’ve enabled customers to share real-time health information with one another.


For example, you can see here the most effective treatments for depression reported by 23andMe customers. These include therapy, exercise, and antidepressants such as Zoloft and Wellbutrin.

You can also see what treatments could potentially lead to worse outcomes. For example, based on the data shared for asthma, inhalers were among the most used and most effective treatment, but they also included some cases where the symptoms got worse. However, “avoiding allergens” was a relatively effective approach without any potential negative effects.

Many treatments are designed for the average patient in mind, but few of us are actually average. We are each unique, and understanding those differences — even small ones — is essential to learn how to better treat conditions and make medical care more personalized. Genetics certainly offers important insight into how we differ in response to treatments. Allowing people to have a place to share their own experience will also aid in our understanding.

For now, the purpose of these pages is to share this crowdsourced information on the effectiveness of treatments. But the information could at some people aid in research into how people of different ethnicities or different genetic makeups respond differently to treatments.

 

The post Crowdsource Treatments for Health Conditions appeared first on 23andMe Blog.

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clumma
6 days ago
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Decades-Old Graph Problem Yields to Amateur Mathematician

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In 1950 Edward Nelson, then a student at the University of Chicago, asked the kind of deceptively simple question that can give mathematicians fits for decades. Imagine, he said, a graph — a collection of points connected by lines. Ensure that all of the lines are exactly the same length, and that everything lies on the plane. Now color all the points, ensuring that no two connected points have the same color. Nelson asked: What is the smallest number of colors that you’d need to color any such graph, even one formed by linking an infinite number of vertices?

The problem, now known as the Hadwiger-Nelson problem or the problem of finding the chromatic number of the plane, has piqued the interest of many mathematicians, including the famously prolific Paul Erdős. Researchers quickly narrowed the possibilities down, finding that the infinite graph can be colored by no fewer than four and no more than seven colors. Other researchers went on to prove a few partial results in the decades that followed, but no one was able to change these bounds.

Then last week, Aubrey de Grey, a biologist known for his claims that people alive today will live to the age of 1,000, posted a paper to the scientific preprint site arxiv.org with the title “The Chromatic Number of the Plane Is at Least 5.” In it, he describes the construction of a planar unit-distance graph that can’t be colored with only four colors. The finding represents the first major advance in solving the problem since shortly after it was introduced. “I got extraordinarily lucky,” de Grey said. “It’s not every day that somebody comes up with the solution to a 60-year-old problem.”

De Grey appears to be an unlikely mathematical trailblazer. He is the co-founder and chief science officer of an organization that aims to develop technologies for “reversing the negative effects of aging.” He found his way to the chromatic number of the plane problem through a board game. Decades ago, de Grey was a competitive Othello player, and he fell in with some mathematicians who were also enthusiasts of the game. They introduced him to graph theory, and he comes back to it now and then. “Occasionally, when I need a rest from my real job, I’ll think about math,” he said. Over Christmas last year, he had a chance to do that.

It is unusual, but not unheard of, for an amateur mathematician to make significant progress on a long-standing open problem. In the 1970s, Marjorie Rice, a homemaker with no mathematical background, ran across a Scientific American column about pentagons that tile the plane. She eventually added four new pentagons to the list. Gil Kalai, a mathematician at the Hebrew University of Jerusalem, said it is gratifying to see a nonprofessional mathematician make a major breakthrough. “It really adds to the many facets of the mathematical experience,” he said.

Perhaps the most famous graph coloring question is the four-color theorem. It states that, assuming every country is one continuous lump, any map can be colored using only four colors so that no two adjacent countries have the same color. The exact sizes and shapes of the countries don’t matter, so mathematicians can translate the problem into the world of graph theory by representing every country as a vertex and connecting two vertices with an edge if the corresponding countries share a border.

The Hadwiger-Nelson problem is a bit different. Instead of considering a finite number of vertices, as there would be on a map, it considers infinitely many vertices, one for each point in the plane. Two points are connected by an edge if they are exactly one unit apart. To find a lower bound for the chromatic number, it suffices to create a graph with a finite number of vertices that requires a particular number of colors. That’s what de Grey did.

De Grey based his graph on a gadget called the Moser spindle, named after mathematical brothers Leo and William Moser. It is a configuration of just seven points and 11 edges that has a chromatic number of four. Through a delicate process, and with minimal computer assistance, de Grey fused copies of the Moser spindle and another small assembly of points into a 20,425-vertex monstrosity that could not be colored using four colors. He was later able to shrink the graph to 1,581 vertices and do a computer check to verify that it was not four-colorable.

The discovery of any graph that requires five colors was a major accomplishment, but mathematicians wanted to see if they could find a smaller graph that would do the same. Perhaps finding a smaller five-color graph — or the smallest possible five-color graph — would give researchers further insight into the Hadwiger-Nelson problem, allowing them to prove that exactly five shades (or six, or seven) are enough to color a graph made from all the points of the plane.

De Grey pitched the problem of finding the minimal five-color graph to Terence Tao, a mathematician at the University of California, Los Angeles, as a potential Polymath problem. Polymath began about 10 years ago when Timothy Gowers, a mathematician at the University of Cambridge, wanted to find a way to facilitate massive online collaborations in mathematics. Work on Polymath problems is done publicly, and anyone can contribute. Recently, de Grey was involved with a Polymath collaboration that led to significant progress on the twin prime problem.

Tao says not every math problem is a good fit for Polymath, but de Grey’s has a few things going for it. The problem is easy to understand and start working on, and there is a clear measure of success: lowering the number of vertices in a non-four-colorable graph. Soon enough, Dustin Mixon, a mathematician at Ohio State University, and his collaborator Boris Alexeev found a graph with 1,577 vertices. On Saturday, Marijn Heule, a computer scientist at the University of Texas, Austin, found one with just 874 vertices. Yesterday he lowered this number to 826 vertices.

Such work has sparked hope that the six-decade-old Hadwiger-Nelson problem is worth another look. “For a problem like this, the final solution might be some incredibly deep mathematics,” said Gordon Royle, a mathematician at the University of Western Australia. “Or it could just be somebody’s ingenuity finding a graph that requires many colors.”



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clumma
8 days ago
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Why SQLite Does Not Use Git

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submitted by /u/Pandalicious to r/programming
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clumma
11 days ago
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