Brazilian astronomers have now found the first evidence of the existence of an exoplanet orbiting an older or more evolved binary in which one of the two stars is dead.

The study resulted from a postdoctoral research project and a research internship abroad, both with scholarships from São Paulo Research Foundation — FAPESP. Its findings have just been published in the Astronomical Journal.

Leonardo Andrade de Almeida, first author of the article, told as follow: “We succeeded in obtaining pretty solid evidence of the existence of a giant exoplanet with a mass almost 13 times that of Jupiter [the largest planet in the Solar System] in an evolved binary system. This is the first confirmation of an exoplanet in a system of this kind.”

Almeida is currently a postdoctoral fellow of the Federal University of Rio Grande do Norte (UFRN), having conducted postdoctoral research at the University of São Paulo’s Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG-USP), where he was supervised by Professor Augusto Damineli, a coauthor of the study.

Clues followed by the researchers to discover the exoplanet in the evolved binary called KIC 10544976, located in the Cygnus constellation in the northern celestial hemisphere, included variations in eclipse timing (the time taken for each of the two stars to eclipse the other) and orbital period.

“Variations in the orbital period of a binary are due to gravitational attraction among the three objects, which orbit around a common center of mass,” Almeida said.

Orbital period variations are not enough to prove the existence of a planet in the case of binaries, however, because binary stars’ magnetic activity fluctuates periodically, just as the Sun’s magnetic field changes polarity every 11 years, with turbulence and the number and size of sunspots peaking and then declining.

“Variations in the Sun’s magnetic activity eventually cause a change in its magnetic field. The same is true of all isolated stars. In binaries, these variations also cause a change in orbital period due to what we call the Applegate mechanism,” Almeida explained.

To refute the hypothesis that variations in the orbital period of KIC 10544976 were due only to magnetic activity, the researchers analyzed the effect of eclipse timing variation and the magnetic activity cycle of the binary’s live star.

KIC 10544976 consists of a white dwarf, a dead low-mass star with a high surface temperature, and a red dwarf, a live (magnetically active) star with a small mass compared to that of our Sun and scant luminosity due to low energy output. The two stars were monitored by ground-based telescopes between 2005 and 2017 and by Kepler between 2009 and 2013, producing data minute by minute.

“The system is unique,” Almeida said. “No similar system has enough data to let us calculate orbital period variation and magnetic cycle activity for the live star.”

Using the Kepler data, they were able to estimate the magnetic cycle of the live star (red dwarf) based on the rate and energy of flares (large eruptions of electromagnetic radiation) and variability due to spots (regions of cooler surface temperature and hence darkness caused by different concentrations of magnetic field flux).

Analysis of the data showed that the red dwarf’s magnetic activity cycle lasted 600 days, which is consistent with the magnetic cycles estimated for low-mass isolated stars. The binary’s orbital period was estimated at 17 years.

“This completely refutes the hypothesis that orbital period variation is due to magnetic activity. The most plausible explanation is the presence of a giant planet orbiting the binary, with a mass approximately 13 times that of Jupiter,” Almeida said.

Formation hypotheses

How the planet orbiting the binary was formed is unknown. One hypothesis is that it developed at the same time as the two stars billions of years ago. If so, it is a first-generation planet. Another hypothesis is that it formed out of the gas ejected during the death of the white dwarf, making it a second-generation planet.

Confirmation of its status as either a first- or second-generation planet and its direct detection as it orbits the binary could be obtained using the new generation of ground-based telescopes with primary mirrors exceeding 20 meters, including the Giant Magellan Telescope (GMT) installed in Chile’s Atacama Desert. The GMT is expected to see first light in 2024.

FAPESP will invest US$40 million in the GMT, or approximately 4% of the telescope’s estimated total cost. This investment will guarantee 4% of the telescope’s operating time for studies by researchers from São Paulo State.

“We’re probing 20 systems in which external bodies could show gravitational effects, such as KIC 10544976, and most are only observable from the southern hemisphere. The GMT will enable us to detect these objects directly and obtain important answers on the formation and evolution of these exotic environments, as well as the possibility of life there,” Almeida said.

Sixteen years after author Michael Lewis wrote the book Moneyball, every Major League Baseball (MLB) team uses the technique. But a new study shows that while the tool can help a club create a stronger team — at a lower cost — it loses its edge once everyone’s on to it.

“It’s like having a secret sauce,” says study author Ramy Elitzur, the Edward J. Kernaghan Professor of Financial Analysis and associate professor of accounting at the University of Toronto’s Rotman School of Management. “When you have a secret sauce and nobody else knows about it, you have a competitive advantage. Once the secret sauce was outed, which was what happened with the book, everybody could imitate the Oakland A’s.”

Dr. Elitzur created a database for the study, inputting information from 1985 to 2013 about team payrolls, playoff success, the spread of data analytics use, and players’ overall contributions to their team, represented by a key statistic from Moneyball’s “sabermetrics,” — the type of data the Oakland A’s used to identify lower-priced, undervalued players through statistics such as how much time spent on base.

He found that between 1997 and 2001, there were only two “Moneyball” teams in the MLB. Another three teams had taken up the practice by 2002. By 2013, more than 75 percent of MLB teams were using it. Sabermetrics gave teams the strongest advantage up until 2003, the year Moneyball was published. By 2008, the comparative advantage was lost as more and more teams adopted sabermetrics. The practice of data analytics also spread beyond sports, to business and government.

The study illustrates that regardless of whether it’s sports or another enterprise, “if you have a built-in advantage, don’t ever talk about it,” says Dr. Elitzur. In the MLB case, “once Moneyball happened, you had a new arms race. There was no way out.” However, it did help teams better match their contracts to players’ true value, he says, by basing it on less biased information.

The paper is forthcoming in Omega, The International Journal of Management Science.

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Since a policy change in November 2018, specialist doctors registered with the General Medical Council (GMC), have been permitted to prescribe new medicines which derive from cannabis. Yet, research into these products has, to date, been limited creating an ‘information vacuum’ about these medicines, their benefits or harms.

A new review authored by leading scientists and clinicians from the University of Bath and University College London (UCL) points to the array of different cannabis-based products and cannabinoids available, and a clear need to educate both patients and clinicians into what these different products do and how they might help.

In particular, it points to important differences between products containing THC (the main psychoactive and intoxicating constituent of cannabis) versus CBD (the non-intoxicating element). Although in certain medicines CBD and THC are combined for clinical benefit, in others these components can work independently, playing different roles in improving certain symptoms.

For example, several studies have found that a combination of THC and CBD can alleviate symptoms of chronic pain, while CBD alone may be effective for treatment-resistant epilepsy. By contrast THC alone may be effective for treating nausea and vomiting caused by chemotherapy. THC and CBD are both ‘cannabinoids’ that act in different ways on the body’s endogenous cannabinoid system.

The cannabis plant produces over 144 different cannabinoids such as THC or CBD. Some medicinal products contain THC and/or CBD derived from the cannabis plant, while others contain synthetically produced cannabinoids. CBD is also available in non-medicinal products such as oils and tinctures.

Lead author, Dr Tom Freeman of the University of Bath’s Addiction and Mental Health Group explains: “In this complex and rapidly evolving field, there are several different cannabis-based and cannabinoid medicinal products. These differ in their THC and CBD content, who can prescribe them, and the conditions they may be used to treat. Here we provide an update for clinicians in advance of forthcoming NICE guidelines.

“A key message is that CBD products widely sold online and in health food shops lack quality standards and should not be treated as medicinal products.”

Research on cannabis was previously restricted because it was listed in Schedule 1, implying that it had no medical value. Cannabis was recently moved to Schedule 2 in the UK.

Dr Freeman adds: “Research on unlicensed cannabis products has been limited to date. The rescheduling of cannabis and allocation of dedicated UK research funding will improve the evidence we have to guide clinical decision-making.”

Co-author, Dr Michael Bloomfield Head of Translational Psychiatry at University College London (UCL) added: “There have been leaps and bounds in our scientific knowledge in recent years, which combined with confusing claims about the medicinal uses of these drugs can be potentially perplexing for doctors and patients. We hope that our new guidance is helpful to doctors and patients worldwide. Much more research is needed into this new class of medicine.”

Co-author Dr Chandni Hindocha of the Clinical Psychopharmacology Unit at UCL added: “Resources must be made available to update and educate clinicians about cannabis and cannabinoid based medicines. We would like to encourage doctors to maintain a compassionate and evidence-based approach when engaging with their patients in this rapidly developing field, in order to provide the best standard of care.”

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The bacterium, Porphyromonas gingivalis, is the bad actor involved in periodontitis, the most serious form of gum disease. These new findings underscore the importance of good dental hygiene as scientists seek ways to better control this common bacterial infection.

“Oral hygiene is very important throughout our life, not only for having a beautiful smile but also to decrease the risk of many serious diseases,” said Jan Potempa, PhD, DSc, a professor at the University of Louisville School of Dentistry and head of the department of microbiology at Jagiellonian University in Krakow, Poland. “People with genetic risk factors that make them susceptible to rheumatoid arthritis or Alzheimer’s disease should be extremely concerned with preventing gum disease.”

While previous researchers have noted the presence of P. gingivalis in brain samples from Alzheimer’s patients, Potempa’s team, in collaboration with Cortexyme, Inc., offers the strongest evidence to date that the bacterium may actually contribute to the development of Alzheimer’s disease. Potempa will present the research at the American Association of Anatomists annual meeting during the 2019 Experimental Biology meeting, held April 6-9 in Orlando, Fla.

The researchers compared brain samples from deceased people with and without Alzheimer’s disease who were roughly the same age when they died. They found P. gingivalis was more common in samples from Alzheimer’s patients, evidenced by the bacterium’s DNA fingerprint and the presence of its key toxins, known as gingipains.

In studies using mice, they showed P. gingivalis can move from the mouth to the brain and that this migration can be blocked by chemicals that interact with gingipains. An experimental drug that blocks gingipains, known as COR388, is currently in phase 1 clinical trials for Alzheimer’s disease. Cortexyme, Inc. and Potempa’s team are working on other compounds that block enzymes important to P. gingivalis and other gum bacteria in hopes of interrupting their role in advancing Alzheimer’s and other diseases.

The researchers also report evidence on the bacterium’s role in the autoimmune disease rheumatoid arthritis, as well as aspiration pneumonia, a lung infection caused by inhaling food or saliva.

“P. gingivalis‘s main toxins, the enzymes the bacterium need to exert its devilish tasks, are good targets for potential new medical interventions to counteract a variety of diseases,” said Potempa. “The beauty of such approaches in comparison to antibiotics is that such interventions are aimed only at key pathogens, leaving alone good, commensal bacteria, which we need.”

P. gingivalis commonly begins to infiltrate the gums during the teenage years. About one in five people under age 30 have low levels of the bacterium in their gums. While it is not harmful in most people, if it grows to large numbers the bacteria provoke the body’s immune system to create inflammation, leading to redness, swelling, bleeding and the erosion of gum tissue.

Making matters worse, P. gingivalis even causes benign bacteria in the mouth to change their activities and further increase the immune response. Bacteria can travel from the mouth into the bloodstream through the simple act of chewing or brushing teeth.

The best way to prevent P. gingivalis from growing out of control is by brushing and flossing regularly and visiting a dental hygienist at least once a year, Potempa said. Smokers and older people are at increased risk for infection. Genetic factors are also thought to play a role, but they are not well understood.

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