Big Think Edge
PURPOSE: Set Goals, with John Amaechi
In this lesson from Big Think Edge, NBA basketball player John Amaechi shares with you the plan he created as a child to help him accomplish his dreams.
INNOVATION: Engage Your Team Through Gaming, with Jane McGonigal
In this lesson from Big Think Edge, game designer Jane McGonigal walks you through the ways in which gaming can lead to positive outcomes in the workplace.
LEADERSHIP: Overcome Obstacles, with Edward Norton
In this lesson from Big Think Edge, Oscar-nominated actor Edward Norton offers a mental strategy for pushing past anxiety and fear when taking on a new venture.
TALENT: Master Your Craft, with Malcolm Gladwell
If your goal is to become masterful at what you do, the formula is simple: stay focused and do your time. In this lesson from Big Think Edge, best-selling author Malcolm Gladwell teaches you how.
Understand and Address Unconscious Bias, with Jennifer Brown
In this lesson from Big Think Edge, management expert Jennifer Brown, a diversity training consultant who works with leading companies, explores pitfalls and strategies for dealing with unconscious bias.
RISK MITIGATION: Risk Management Fundamentals, with Timothy Geithner
In this lesson from Big Think Edge, former U.S. Secretary of the Treasury Timothy Geithner teaches the fundamentals of risk management, based on lessons learned during the 2008 Financial Crisis.
MILLENNIALS: Embrace Millennials' Values, with Jon Iwata
In this lesson from Big Think Edge, Jon Iwata, Senior Vice President of Marketing and Communications at IBM, explores key millennial values and what every company can do to embrace them.
MASTERCLASS: What Does A Leader Do?, with Robert Kaplan
In this lesson from Big Think Edge, Harvard professor and former Goldman Sachs executive Robert S. Kaplan explores three strategic key questions that leaders need to ask themselves.
Introducing Big Think Edge
Big Think's Edge learning platform for career mentorship and professional development provides engaging and actionable courses delivered by thought leaders at the top of their game.
Using a machine-learning algorithm, MIT researchers have identified a powerful new antibiotic compound. In laboratory tests, the drug killed many of the world's most problematic disease-causing bacteria, including some strains that are resistant to all known antibiotics. It also cleared infections in two different mouse models.
The computer model, which can screen more than a hundred million chemical compounds in a matter of days, is designed to pick out potential antibiotics that kill bacteria using different mechanisms than those of existing drugs.
"We wanted to develop a platform that would allow us to harness the power of artificial intelligence to usher in a new age of antibiotic drug discovery," says James Collins, the Termeer Professor of Medical Engineering and Science in MIT's Institute for Medical Engineering and Science (IMES) and Department of Biological Engineering. "Our approach revealed this amazing molecule which is arguably one of the more powerful antibiotics that has been discovered."
In their new study, the researchers also identified several other promising antibiotic candidates, which they plan to test further. They believe the model could also be used to design new drugs, based on what it has learned about chemical structures that enable drugs to kill bacteria.
"The machine learning model can explore, in silico, large chemical spaces that can be prohibitively expensive for traditional experimental approaches," says Regina Barzilay, the Delta Electronics Professor of Electrical Engineering and Computer Science in MIT's Computer Science and Artificial Intelligence Laboratory (CSAIL).
Barzilay and Collins, who are faculty co-leads for MIT's Abdul Latif Jameel Clinic for Machine Learning in Health (J-Clinic), are the senior authors of the study, which appears today in Cell. The first author of the paper is Jonathan Stokes, a postdoc at MIT and the Broad Institute of MIT and Harvard.
A new pipeline
Over the past few decades, very few new antibiotics have been developed, and most of those newly approved antibiotics are slightly different variants of existing drugs. Current methods for screening new antibiotics are often prohibitively costly, require a significant time investment, and are usually limited to a narrow spectrum of chemical diversity.
"We're facing a growing crisis around antibiotic resistance, and this situation is being generated by both an increasing number of pathogens becoming resistant to existing antibiotics, and an anemic pipeline in the biotech and pharmaceutical industries for new antibiotics," Collins says.
To try to find completely novel compounds, he teamed up with Barzilay, Professor Tommi Jaakkola, and their students Kevin Yang, Kyle Swanson, and Wengong Jin, who have previously developed machine-learning computer models that can be trained to analyze the molecular structures of compounds and correlate them with particular traits, such as the ability to kill bacteria.
The idea of using predictive computer models for "in silico" screening is not new, but until now, these models were not sufficiently accurate to transform drug discovery. Previously, molecules were represented as vectors reflecting the presence or absence of certain chemical groups. However, the new neural networks can learn these representations automatically, mapping molecules into continuous vectors which are subsequently used to predict their properties.
In this case, the researchers designed their model to look for chemical features that make molecules effective at killing E. coli. To do so, they trained the model on about 2,500 molecules, including about 1,700 FDA-approved drugs and a set of 800 natural products with diverse structures and a wide range of bioactivities.
Once the model was trained, the researchers tested it on the Broad Institute's Drug Repurposing Hub, a library of about 6,000 compounds. The model picked out one molecule that was predicted to have strong antibacterial activity and had a chemical structure different from any existing antibiotics. Using a different machine-learning model, the researchers also showed that this molecule would likely have low toxicity to human cells.
This molecule, which the researchers decided to call halicin, after the fictional artificial intelligence system from "2001: A Space Odyssey," has been previously investigated as possible diabetes drug. The researchers tested it against dozens of bacterial strains isolated from patients and grown in lab dishes, and found that it was able to kill many that are resistant to treatment, including Clostridium difficile, Acinetobacter baumannii, and Mycobacterium tuberculosis. The drug worked against every species that they tested, with the exception of Pseudomonas aeruginosa, a difficult-to-treat lung pathogen.
To test halicin's effectiveness in living animals, the researchers used it to treat mice infected with A. baumannii, a bacterium that has infected many U.S. soldiers stationed in Iraq and Afghanistan. The strain of A. baumannii that they used is resistant to all known antibiotics, but application of a halicin-containing ointment completely cleared the infections within 24 hours.
Preliminary studies suggest that halicin kills bacteria by disrupting their ability to maintain an electrochemical gradient across their cell membranes. This gradient is necessary, among other functions, to produce ATP (molecules that cells use to store energy), so if the gradient breaks down, the cells die. This type of killing mechanism could be difficult for bacteria to develop resistance to, the researchers say.
"When you're dealing with a molecule that likely associates with membrane components, a cell can't necessarily acquire a single mutation or a couple of mutations to change the chemistry of the outer membrane. Mutations like that tend to be far more complex to acquire evolutionarily," Stokes says.
In this study, the researchers found that E. coli did not develop any resistance to halicin during a 30-day treatment period. In contrast, the bacteria started to develop resistance to the antibiotic ciprofloxacin within one to three days, and after 30 days, the bacteria were about 200 times more resistant to ciprofloxacin than they were at the beginning of the experiment.
The researchers plan to pursue further studies of halicin, working with a pharmaceutical company or nonprofit organization, in hopes of developing it for use in humans.
After identifying halicin, the researchers also used their model to screen more than 100 million molecules selected from the ZINC15 database, an online collection of about 1.5 billion chemical compounds. This screen, which took only three days, identified 23 candidates that were structurally dissimilar from existing antibiotics and predicted to be nontoxic to human cells.
In laboratory tests against five species of bacteria, the researchers found that eight of the molecules showed antibacterial activity, and two were particularly powerful. The researchers now plan to test these molecules further, and also to screen more of the ZINC15 database.
The researchers also plan to use their model to design new antibiotics and to optimize existing molecules. For example, they could train the model to add features that would make a particular antibiotic target only certain bacteria, preventing it from killing beneficial bacteria in a patient's digestive tract.
"This groundbreaking work signifies a paradigm shift in antibiotic discovery and indeed in drug discovery more generally," says Roy Kishony, a professor of biology and computer science at Technion (the Israel Institute of Technology), who was not involved in the study. "Beyond in silica screens, this approach will allow using deep learning at all stages of antibiotic development, from discovery to improved efficacy and toxicity through drug modifications and medicinal chemistry."
The research was funded by the Abdul Latif Jameel Clinic for Machine Learning in Health, the Defense Threat Reduction Agency, the Broad Institute, the DARPA Make-It Program, the Canadian Institutes of Health Research, the Canadian Foundation for Innovation, the Canada Research Chairs Program, the Banting Fellowships Program, the Human Frontier Science Program, the Pershing Square Foundation, the Swiss National Science Foundation, a National Institutes of Health Early Investigator Award, the National Science Foundation Graduate Research Fellowship Program, and a gift from Anita and Josh Bekenstein.
On April 13, 2029, an icy chunk of space rock, wider than the Eiffel Tower is tall, will streak by Earth at 30 kilometers per second, grazing the planet's sphere of geostationary satellites.
It will be the closest approach by one of the largest asteroids crossing Earth's orbit in the next decade.
Observations of the asteroid, known as 99942 Apophis, for the Egyptian god of chaos, once suggested that its 2029 flyby would take it through a gravitational keyhole — a location in Earth's gravity field that would tug the asteroid's trajectory such that on its next flyby, in the year 2036, it would likely make a devastating impact.
Thankfully, more recent observations have confirmed that the asteroid will sling by Earth without incident in both 2029 and 2036. Nevertheless, most scientists believe it is never too early to consider strategies for deflecting an asteroid if one were ever on a crash course with our home planet.
Now MIT researchers have devised a framework for deciding which type of mission would be most successful in deflecting an incoming asteroid. Their decision method takes into account an asteroid's mass and momentum, its proximity to a gravitational keyhole, and the amount of warning time that scientists have of an impending collision — all of which have degrees of uncertainty, which the researchers also factor in to identify the most successful mission for a given asteroid.
The researchers applied their method to Apophis, and Bennu, another near-Earth asteroid which is the target of OSIRIS-REx, an operational NASA mission that plans to return a sample of Bennu's surface material to Earth in 2023. REXIS, an instrument designed and built by students at MIT, is also part of this mission and its task is to characterize the abundance of chemical elements at the surface.
In a paper appearing this month in the journal Acta Astronautica, the researchers use their decision map to lay out the type of mission that would likely have the most success in deflecting Apophis and Bennu, in various scenarios in which the asteroids may be headed toward a gravitational keyhole. They say the method could be used to design the optimal mission configuration and campaign to deflect a potentially hazardous near-Earth asteroid.
"People have mostly considered strategies of last-minute deflection, when the asteroid has already passed through a keyhole and is heading toward a collision with Earth," says Sung Wook Paek, lead author of the study and a former graduate student in MIT's Department of Aeronautics and Astronautics. "I'm interested in preventing keyhole passage well before Earth impact. It's like a preemptive strike, with less mess."
Paek's co-authors at MIT are Olivier de Weck, Jeffrey Hoffman, Richard Binzel, and David Miller.
Deflecting a planet-killer
In 2007, NASA concluded in a report submitted to the U.S. Congress that in the event that an asteroid were headed toward Earth, the most effective way to deflect it would be to launch a nuclear bomb into space. The force of its detonation would blast the asteroid away, though the planet would then have to contend with any nuclear fallout. The use of nuclear weapons to mitigate asteroid impacts remains a controversial issue in the planetary defense community.
The second best option was to send up a "kinetic impactor" — a spacecraft, rocket, or other projectile that, if aimed at just the right direction, with adequate speed, should collide with the asteroid, transfer some fraction of its momentum, and veer it off course.
"The basic physics principle is sort of like playing billiards," Paek explains.
For any kinetic impactor to be successful, however, de Weck, a professor of aeronautics and astronautics and engineering systems, says the properties of the asteroid, such as its mass, momentum, trajectory, and surface composition must be known "as precisely as possible." That means that, in designing a deflection mission, scientists and mission managers need to take uncertainty into account.
"Does it matter if the probability of success of a mission is 99.9 percent or only 90 percent? When it comes to deflecting a potential planet-killer, you bet it does," de Weck says. "Therefore we have to be smarter when we design missions as a function of the level of uncertainty. No one has looked at the problem this way before."
Closing a keyhole
Paek and his colleagues developed a simulation code to identify the type of asteroid deflection mission that would have the best possibility of success, given an asteroid's set of uncertain properties.
The missions they considered include a basic kinetic impactor, in which a projectile is shot into space to nudge an asteroid off course. Other variations involved sending a scout to first measure the asteroid to hone the specs of a projectile that would be sent up later, or sending two scouts, one to measure the asteroid and the other to push the asteroid slightly off course before a larger projectile is subsequently launched to make the asteroid miss Earth with near certainty.
The researchers fed into the simulation specific variables such as the asteroid's mass, momentum, and trajectory, as well as the range of uncertainty in each of these variables. Most importantly, they factored in an asteroid's proximity to a gravitational keyhole, as well as the amount of time scientists have before an asteroid passes through the keyhole.
"A keyhole is like a door — once it's open, the asteroid will impact Earth soon after, with high probability," Paek says.
The researchers tested their simulation on Apophis and Bennu, two of only a handful of asteroids for which the locations of their gravitational keyholes with respect to Earth are known. They simulated various distances between each asteroid and their respective keyhole, and also calculated for each distance a "safe harbor" region where an asteroid would have to be deflected so that it would avoid both an impact with Earth and passing through any other nearby keyhole.
They then evaluated which of the three main mission types would be most successful at deflecting the asteroid into a safe harbor, depending on the amount of time scientists have to prepare.
For instance, if Apophis will pass through a keyhole in five years or more, then there is enough time to send two scouts — one to measure the asteroid's dimensions and the other to nudge it slightly off track as a test — before sending a main impactor. If keyhole passage occurs within two to five years, there may be time to send one scout to measure the asteroid and tune the parameters of a larger projectile before sending the impactor up to divert the asteroid. If Apophis passes through its keyhole within one Earth year or less, Paek says it may be too late.
"Even a main impactor may not be able to reach the asteroid within this timeframe," Paek says.
Bennu is a similar case, although scientists know a bit more about its material composition, which means that it may not be necessary to send up investigatory scouts before launching a projectile.
With the team's new simulation tool, Peak plans to estimate the success of other deflection missions in the future.
"Instead of changing the size of a projectile, we may be able to change the number of launches and send up multiple smaller spacecraft to collide with an asteroid, one by one. Or we could launch projectiles from the moon or use defunct satellites as kinetic impactors," Paek says. "We've created a decision map which can help in prototyping a mission."
This research was supported, in part, by NASA, Draper Laboratory, and the Samsung Foundation of Culture.
- Chris Hughes, cofounder of Facebook, sees universal basic income as a way to stabilize the lives of those who need it most. A foundation of $500 per month could solve many of today's economic problems.
- Much of the criticism surrounding UBI comes from a place of myth and mistrust. If you give someone cash, how can you be sure they'll spend it responsibly? The fact is, cash is the most effective way of providing economic mobility.
- To reboot the American dream, we must address the moral and practical issue that many Americans lack basic financial stability. To bolster the economy and avoid another depression, UBI could be the answer.
- The Catholic rite of Holy Communion parallels pre-Christian Greco-Roman and Egyptian rituals that involved eating the body and blood of a god.
- A number of Catholic holidays and myths, such as Christmas, Easter, and Mardi Gras, graph onto the timeline of pre-Christian fertility festivals.
- The Catholic practice of praying to saints has been called "de-facto idolatry" and even a relic of goddess worship.
By the fourth century, the Christian Church had established itself as the official faith of the Roman Empire through a successful grassroots campaign to dominate, and almost exterminate, paganism. But did it?
In reality, the early Church had to merge itself with pagan practices and beliefs in order to blend into Roman society. In the rites and symbols of the Roman Catholic Church, we can find surviving, though rebranded, pre-Christian myths, deities, festivals, and rituals. Here are three Catholic practices that can be traced back to ancient pagan religions and cults.
Photo by Debby Hudson / Unsplash
One of the more fascinating elements of Catholicism is the ritual cannibalistic consumption of their "demigod" known as Holy Communion or Eucharist. During Catholic mass, bread and wine are transformed into the flesh and blood of Jesus Christ, who is considered the son of God, in a rite called "transubstantiation." This isn't a symbolic transformation. A core teaching of the Catholic faith is the belief in literal transubstantiation. Practitioners eat the body and blood of Christ to become one with God.
Similar rituals were practiced in the underground "mystery religions" of the Greco-Roman world. In a few of those occult religions, celebrants shared a communal meal in which they symbolically feasted on the flesh and got drunk on the blood of their god. For example, the Mithraic Mysteries, or Mithraism, was a mystery cult practiced in the Roman Empire in 300 BC in which followers worshipped the Indo-Iranian deity Mithram, the god of friendship, contract, and order. Mirroring the Catholic Eucharistic rite, the idea of transubstantiation was a characteristic of Mithraic sacraments that included cake and Haoma drink. But the ritual probably wasn't original to Mithraism either. In Egypt around 3100 BC, priests would consecrate cakes which were to become the flesh of the god Osiris and eaten.
Holy Days and Carnivals
The survival of ancient communities was intimately dependent upon the fertility of the land, so their religious symbolism and festivals reflected this fundamental bond between humans and the cycles of nature. A number of Catholic holidays and myths parallel the timeline and adopt the symbols of pre-Christian fertility festivals. In Catholicism, Jesus Christ is thought to have been born on December 25, Christmas Day. In pre-Christian Roman religions, the Winter Solstice was a core sacred event that took place on December 25 at the time of the Julian calendar. The best known custom was the Roman festival of Saturnalia, which was celebrated similar to Christmas with drinking, fires, gift-giving, and tree worship.
Similarly, the Catholic Fat Tuesday, otherwise known as Mardi Gras, is rooted in the pre-Christian Roman celebration of Lupercalia. A February holiday honoring the Roman god of fertility, its customs involved feasting, drinking, and "carnal behavior." Today, the same can be said of Mardi Gras, when Catholics (as well as non-Catholics) eat festival foods and party before abstaining for 40 days during Lent.
When it comes to Easter, celebrated on the first Sunday after the first full moon after the vernal equinox, the symbolic story of the death of a god (or sun/son) and springtime rebirth is a tale as old as time. The spring equinox was recognized by various pagan cults as a festival marking the resurrection of light triumphing over darkness and the fresh fecundity of the land. One such festival was Eostre, which celebrated a northern goddess of the same name. Her symbol was the prolific hare representing fertility.
Speaking of goddesses...
Goddess Worship: The Virgin Mary and Saint Brigid
Photo by Grant Whitty / Unsplash
Though theoretically monotheistic, the Catholic practice of praying to saints has been called "de-facto idolatry" and even a relic of goddess worship. Rebranded pagan goddesses can be found in the Catholic Church today in forms of Saint Brigid and the Virgin Mary.
Mary, the Virgin Mother of Christ, is arguably the most important Catholic icon save for the Holy Trinity. She's likely the amalgamation of pre-Christian mother goddesses from antiquity whose ranks include Artemis, Demeter, Diana, Hera, Isis, and Venus. The cult of the Egyptian goddess Isis may have had a particularly strong influence on Christian myth. While historical records can not substantiate this entirely, there is physical evidence of statues of Isis cradling Horus that were converted and reused as the Virgin Mary holding Jesus.
Brigid, the beloved Celtic goddess associated with fertility and healing, is perhaps the clearest example of the survival of an early goddess into Catholicism. Practitioners, particularly in Ireland, pay tribute to Saint Brigid of Ireland who shares many of the early goddess's attributes. Her feast day on the first of February falls around the same time as the pagan celebration of Imbolc.
The appropriation of these pagan practices and symbols by the Catholic Church shows how, as social interests change and new institutions are established, religious myths and practices are not so easily exterminated. Today, millions of Catholics eating the body and blood of their god, bowing their heads to feminine idols and celebrating natural cycles on the Liturgical Calendar are still worshiping in the ways of the ancient pagans.
- Intentional or not, certain inequalities are inherent in a digital economy that is structured and controlled by a few corporations that don't represent the interests or the demographics of the majority.
- While concern and anger are valid reactions to these inequalities, UCLA professor Ramesh Srinivasan also sees it as an opportunity to take action.
- Srinivasan says that the digital economy can be reshaped to benefit the 99 percent if we protect laborers in the gig economy, get independent journalists involved with the design of algorithmic news systems, support small businesses, and find ways that groups that have been historically discriminated against can be a part of these solutions.