Wednesday, September 01, 2021

Dogs distinguish between intentional and unintentional action

Dogs tell the difference between intentional and unintentional action
Dogs and experimenter sat on opposite sides of the partition. Dogs were fed through 
the gap in the partition. Credit: Katharina Schulte

Over their long shared history, dogs have developed a range of skills for bonding with human beings. Their ability to make sense of human actions, demonstrated by every "sit," "lay down," and "roll over," is just one such skill. But whether dogs understand human intentions, or merely respond to outcomes, remains unclear. The ability to recognize another's intentions—or at least conceive of them—is a basic component of theory of mind, the ability to attribute mental states to oneself and others, long regarded as uniquely human. Do dogs have this basic component of theory of mind, the ability to tell the difference between something done on purpose and something done by accident?

To answer this question, a team of researchers in Germany conducted an experiment that examined how dogs reacted when  were withheld, both intentionally and unintentionally. They found that dogs respond differently depending on whether the actions of the experimenter were intentional or unintentional. This, the researchers say, shows that dogs can distinguish between actions that were done on purpose or accidentally.

To reach their conclusions, the researchers conducted an experiment using the "unable vs. unwilling" paradigm. This works by examining whether  react differently toward a human experimenter who either intentionally (the unwilling condition) or unintentionally (the unable condition) withholds rewards from them. Despite being an established paradigm in studies of human and animal cognition, the unable vs. unwilling paradigm had never been previously used to investigate dogs.

The experiment was conducted with 51 dogs, each of which was tested under three conditions. In each condition, the dog was separated from the human tester by a transparent . The basic situation was that the experimenter fed the dog pieces of dog food through a gap in the barrier. In the "unwilling" condition, the experimenter suddenly withdrew the  through the gap in the barrier and placed it in front of herself. In the "unable-clumsy" condition, the experimenter brought the reward to the gap in the barrier and "tried" to pass it through the gap but then "accidentally" dropped it. In the "unable-blocked" condition, the experimenter again tried to give the dog a reward, but was unable to because the gap in the barrier was blocked. In all conditions, the reward remained on the tester's side of the barrier.

Dogs tell the difference between intentional and unintentional action
Dogs went around the partition to access the withheld rewards faster when these 
were withheld unintentionally than when they were withheld intentionally.
 Credit: Josepha Erlacher

"If dogs are indeed able to ascribe intention in action to humans," says Dr. Juliane Bräuer, "we would expect them to show different reactions in the unwilling condition compared to the two unable conditions. As it turns out, this is exactly what we observed."

The primary behavior measured by the researchers was the time dogs waited before approaching the reward they were denied. The researchers predicted that, if dogs are able to identify human intentions, they would wait longer before approaching the reward in the unwilling condition, where they were not supposed to have the reward, than in the two unable conditions in which the reward was, in fact, meant for them.

Not only did the dogs wait longer in the unwilling condition than in the unable conditions, they were also more likely to sit or lie down—actions often interpreted as appeasing behaviors—and stop wagging their tails.

Dogs tell the difference between intentional and unintentional action
Dogs were fed through the gap before the experimenter started to withhold the reward 
intentionally or unintentionally. Credit: Josepha Erlacher
"The dogs in our study clearly behaved differently depending on whether the actions of a human experimenter were intentional or unintentional," says Britta Schünemann, the first author of the study. "This suggests that dogs may indeed be able to identify humans' intention-in-action," adds Hannes Rakoczy from the University of Göttingen.

The team acknowledges that their findings may be met with skepticism and that further study is needed to address alternative explanations, such as behavioral cues on the part of experimenters or knowledge transfer from prior dog training.

"Nevertheless," the paper concludes, "the findings present important initial evidence that  may have at least one aspect of theory of mind: The capacity to recognize intention-in-action."

The study is published in Scientific Reports.

Dogs may not return their owners' good deeds
More information: Britta Schünemann et al, Dogs distinguish human intentional and unintentional action, Scientific Reports (2021). DOI: 10.1038/s41598-021-94374-3
Journal information: Scientific Reports 
Provided by Max Planck Society 

Raining microbes? New study finds rain-borne bacteria colonize plants


Peer-Reviewed Publication

AMERICAN PHYTOPATHOLOGICAL SOCIETY

When it rains, plants are not only showered with water, but also microbes.  These rain-borne microbes have the opportunity to become part of a plant’s aboveground microbial community – known as the phyllosphere. Phyllosphere microbes can protect plants from disease and other stressors and understanding where they come from may help us improve plant health.  While plant microbiome research has historically focused on soil and seeds as sources of plant-associated microbes, new findings by scientists at Virginia Tech University suggest that rain may also be an important reservoir. 

A study recently published in Phytobiomes Journal led by Marco Mechan-Llontop and Boris Vinatzer examined rain as a reservoir of phyllosphere bacteria. After finding greater densities of microbes on the leaves of rain-exposed tomato plants compared to those grown in the lab, they set out to experimentally test whether rain-borne microbes could successfully colonize the phyllosphere of tomato plants.  “Although this is a simple question, it is actually really hard to answer since plants outside are exposed to many bacteria that come from the soil, rain, and the air,” noted Vinatzer.  

Additionally, while rain may contain important microbes, their quantities may be small–a milliliter of rain might only contain a few microbial cells.  To control for other external sources of microbes and inoculate plants with measurable doses of rain-borne microbes, Vinatzer and colleagues performed a laboratory experiment with rain they collected. They filtered the rainwater to obtain sterilized water and membranes containing the bacterial microbiota. These membranes were incubated to obtain a highly concentrated inoculum of rain-borne bacteria. They sprayed plants with this inoculum or with sterilized rainwater and distilled water (as negative controls) and incubated the plants for one week before characterizing their bacterial communities via DNA analyses.

Their analysis showed that inoculating plants with the rainwater microbial communities increased the abundance of over 100 bacterial taxa, indicating that microbes in rain can successfully colonize and grow on the surface of plants. This suggests rain is a potentially important reservoir for phyllosphere bacteria. The authors hope this research will pave the way for more research into the origins of plant-associated microorganisms and microbes that are efficiently distributed by rain. “The more we know about these bacteria, the better we can use them to our advantage to improve plant health,” says Vinatzer. For example, bacteria that suppress plant pathogens could be sprayed onto leaves to reduce or prevent disease.  The authors plan to continue their research examining the importance of rain in phyllosphere assembly and hope to identify beneficial bacteria from rain.

Read more about this research in “Experimental Evidence Pointing to Rain as a Reservoir of Tomato Phyllosphere Microbiota” by Marco Mechan-Llontop, Long Tian, Parul Sharma, Logan Heflin, Vivian Bernal-Galeano, David Haak, Christopher Clarke, and Boris Vinatzer. 

Lead author Marco E. Mechan-Llontop is currently a postdoctoral researcher in the Shade Lab at Michigan State University. Senior author Boris Vinatzer is a professor in the School of Plant and Environmental Sciences at Virginia Tech.

Author information: Eric Wang is a student at Millburn High School and is interested in how plant-microbial interactions vary among different kinds of plants. Mia Howard (@mia_how) is an assistant feature editor for Phytobiomes Journal and a postdoctoral researcher in the Lau Lab at Indiana University.  She is fascinated by how plants—often with help from microbes—protect themselves from herbivores with toxic chemicals.

Extreme sea levels to become much more common worldwide as Earth warms


Critical coastal events, happening once a century in recent times, to occur every year on average


Peer-Reviewed Publication

DOE/PACIFIC NORTHWEST NATIONAL LABORATORY

COLLEGE PARK, Md.—The news has been packed in recent months with severe climate and weather events—record-high temperatures from the Pacific Northwest to Sicily, flooding in Germany and the eastern United States, wildfires from Sacramento to Siberia to Greece. Events that seemed rare just a few decades ago are now commonplace.

A new study, appearing in the journal Nature Climate Change August 30, looks specifically at extreme sea levels—the occurrence of exceptionally high seas due to the combination of tide, waves and storm surge. The study predicts that because of rising temperatures, extreme sea levels along coastlines the world over will become 100 times more frequent by the end of the century in about half of the 7,283 locations studied. That means, because of rising temperatures, an extreme sea level event that would have been expected to occur once every 100 years currently is expected to occur, on average, every year by the end of this century.

While the researchers say there is uncertainty—as always—about future climate, the most likely path is that these increased instances of sea level rise will occur even with a global temperature increase of 1.5 or 2 degrees Celsius compared to preindustrial temperatures. Scientists consider these temperatures the lower end of possible global warming. And the changes are likely to come sooner than the end of the century, with many locations experiencing a 100-fold increase in extreme sea level events by 2070.

 

Mapping effects, location by location

Claudia Tebaldi, a climate scientist at the Department of Energy’s Pacific Northwest National Laboratory, led an international team of researchers in the analysis. She brought together scientists who have led previous large studies of extreme sea levels and the effects of temperatures on sea level rise. The team pooled its data and introduced a novel synthesis method, treating the alternative estimates as expert voters, to map out likely effects of temperature increases ranging from 1.5 C to 5 C compared to preindustrial times.

The scientists found, not unexpectedly, that the effects of rising seas on extreme sea level frequency would be felt most acutely in the tropics and generally at lower latitudes compared to northern locations. Locations likely to be affected most include the Southern Hemisphere, areas along the Mediterranean Sea and the Arabian Peninsula, the southern half of North America’s Pacific coast, and areas including Hawaii, the Caribbean, the Philippines and Indonesia. In many of these regions, sea level is expected to rise faster than at higher latitudes.

Regions that will be less affected include the higher latitudes, the northern Pacific coast of North America, and the Pacific coast of Asia.

“One of our central questions driving this study was this: How much warming will it take to make what has been known as a 100-year event an annual event? Our answer is, not much more than what has already been documented,” said Tebaldi, who notes that the globe has already warmed about 1 C compared to preindustrial times.

The new study mirrors the assertion of the 2019 Intergovernmental Panel on Climate Change report, which stated that extreme sea level events would become much more common worldwide by the end of the century due to global warming.

“It’s not huge news that sea level rise will be dramatic even at 1.5 degrees and will have substantial effects on extreme sea level frequencies and magnitude” said Tebaldi. “This study gives a more complete picture around the globe. We were able to look at a wider range of warming levels in very fine spatial detail.”

The best- and worst-case scenarios put forth by the study vary, due to uncertainties that the study authors represented in remarkable detail. In one scenario, at the pessimistic end, 99 percent of locations studied will experience a 100-fold increase in extreme events by 2100 at 1.5 C of warming. In another, at the optimistic end, about 70 percent of locations don’t see much of a change even with a temperature increase of 5 C.

The authors call for more study to understand precisely how the changes will affect particular communities. They point out that the physical changes that their study describes will have varying impacts at local scales, depending on several factors, including how vulnerable the site is to rising waters and how prepared a community is for change.

Authors of the paper include Roshanka Ranasinghe of the IHE Delft Institute for Water Education in the Netherlands; Michalis Vousdoukas of the European Joint Research Centre in Italy; D.J. Rasmussen of Princeton University; Ben Vega-Westhoff and Ryan Sriver of the University of Illinois at Urbana-Champaign; Ebru Kirezci of the University of Melbourne in Australia; Robert E. Kopp of Rutgers University; and Lorenzo Mentaschi of the University of Bologna in Italy.

Tebaldi, the corresponding author, is a scientist at the Joint Global Change Research Institute, a partnership between PNNL and the University of Maryland where researchers explore the interactions between human, energy and environmental systems.

The study was funded by the U.S. Environmental Protection Agency and DOE’s Office of Science.

 

# # #

Pacific Northwest National Laboratory draws on its distinguishing strengths in chemistryEarth sciencesbiology and data science to advance scientific knowledge and address challenges in sustainable energy and national security. Founded in 1965, PNNL is operated by Battelle for the Department of Energy’s Office of Science, which is the single largest supporter of basic research in the physical sciences in the United States. DOE’s Office of Science is working to address some of the most pressing challenges of our time. For more information, visit PNNL's News Center. Follow us on TwitterFacebookLinkedIn and Instagram.

Antibiotics increase the risk of colon cancer


Peer-Reviewed Publication

UMEA UNIVERSITY

Sophia Harlid 

IMAGE: SOPHIA HARLID, RESEARCHER AT DEPARTMENT OF RADIATION SCIENCES, UMEÅ UNIVERSITY, SWEDEN. view more 

CREDIT: MATTIAS PETTERSSON.

There is a clear link between taking antibiotics and an increased risk of developing colon cancer within the next five to ten years. This has been confirmed by researchers at Umeå University, Sweden, after a study of 40,000 cancer cases. The impact of antibiotics on the intestinal microbiome is thought to lie behind the increased risk of cancer.

“The results underline the fact that there are many reasons to be restrictive with antibiotics. While in many cases antibiotic therapy is necessary and saves lives, in the event of less serious ailments that can be expected to heal anyway, caution should be exercised. Above all to prevent bacteria from developing resistance but, as this study shows, also because antibiotics may increase the risk of future colon cancer,” explains Sophia Harlid, cancer researcher at Umeå University.

Researchers found that both women and men who took antibiotics for over six months ran a 17 per cent greater risk of developing cancer in the ascending colon, the first part of the colon to be reached by food after the small intestine, than those who were not prescribed any antibiotics. However, no increased risk was found for cancer in the descending colon. Nor was there an increased risk of rectal cancer in men taking antibiotics, while women taking antibiotics had a slightly reduced incidence of rectal cancer.

The increased risk of colon cancer was visible already five to ten years after taking antibiotics. Although the increase in risk was greatest for those taking most antibiotics, it was also possible to observe an admittedly small, but statistically significant, increase in the risk of cancer after a single course of antibiotics.

The present study uses data on 40,000 patients from the Swedish Colorectal Cancer Registry from the period 2010–2016. These have been compared to a matched control group of 200,000 cancer-free individuals drawn from the Swedish population at large. Data on the individuals’ antibiotic use was collected from the Swedish Prescribed Drug Register for the period 2005–2016. The Swedish study broadly confirms the results of an earlier, somewhat smaller British study.

In order to understand how antibiotics increase the risk, the researchers also studied a non-antibiotic bactericidal drug used against urinary infections that does not affect the microbiome. There was no difference in the frequency of colon cancer in those who used this drug, suggesting that it is the impact of antibiotics on the microbiome that increases the risk of cancer. While the study only covers orally administered antibiotics, even intravenous antibiotics may affect the gut microbiota in the intestinal system.

“There is absolutely no cause for alarm simply because you have taken antibiotics. The increase in risk is moderate and the affect on the absolute risk to the individual is fairly small. Sweden is also in the process of introducing routine screening for colorectal cancer. Like any other screening programme, it is important to take part so that any cancer can be detected early or even prevented, as cancer precursors can sometimes be removed,” says Sophia Harlid. 

New research in American Journal of Psychiatry identifies risk factors for suicide attempt among soldiers


Peer-Reviewed Publication

AMERICAN PSYCHIATRIC ASSOCIATION

New research in the American Journal of Psychiatry identifies factors that may help assess suicide risk in soldiers. According to the study, Predictors of Suicide Attempt Within 30 Days After First Medically Documented Suicidal Ideation in U.S. Army Soldiers, suicide risk was highest within 30 days after ideation diagnosis and was more likely among women and combat medics.   

“This Suicide Prevention Month, it’s important to remember that research can help us better understand risk factors and which populations are more vulnerable,” said APA President Vivian Pender, M.D.  “It is also a reminder that we can all play a role in preventing suicide by learning to recognize signs of distress and reaching out to connect anyone at risk with help.”

The authors examined risk factors for suicide attempt within the first month after a diagnosis of suicidal ideation, looking at sociodemographic and service-related characteristics, psychiatric diagnoses, physical health care visits, injuries, and others. Using data from the Army Study to Assess Risk and Resilience in Servicemembers, the researchers reviewed records from more than 11,000 active duty enlisted soldiers with documented suicidal ideation and no prior documented suicide attempts.

About half (52.7%) of the solders identified with suicide ideation were in their first two years of service and 57.7% had never deployed. About 80% had had at least one outpatient visit in the previous two months. The most common psychiatric diagnoses were depression and related disorders, tobacco use disorder, anxiety disorder and adjustment disorder.  
 

In the study, 7.4% soldiers with suicidal ideation subsequently attempted suicide. Almost half of the attempts, 3.5%, occurred within 30 days after suicidal ideation. The risk for suicide attempt was highest on the first day after suicidal ideation diagnosis and decreased over time.

 

The study found that females, combat medics, individuals with an anxiety disorder diagnosis prior to suicidal ideation, and those diagnosed with a sleep disorder on the same day as the suicidal ideation were more likely to attempt suicide within 30 days.

"Identifying suicide risk in the population, in patients in primary care, and in patients in psychiatric care who frequently have suicide ideation, are all challenging and different questions,” said Robert J. Ursano, M.D., one of the study authors and Director, Center for the Study of Traumatic Stress, Uniformed Services University. “This paper importantly speaks to psychiatrists and other mental health care providers who have to make difficult treatment and management decisions for those specifically struggling with suicide ideation."

While depression-related diagnoses were common among the soldiers with suicide ideation, they were not associated with an increased risk of suicide attempt during the first month. Major depression was diagnosed in 24% of soldiers with suicide ideation and depression-related diagnoses (such as dysthymic disorder and adjustment disorder with depressed mood) were diagnosed in nearly 60% of soldiers on the same day suicide ideation was diagnosed. A diagnosis of posttraumatic stress disorder was also not associated with an increased risk of suicide attempt within 30 days. 

 

     National Suicide Prevention Lifeline                   Crisis Textline
     800-273-8255 or Chat with Lifeline                    Text TALK to 741741                             


More information

See also two recent articles on suicide risk published in the APA journal Psychiatric Services:

More information is available in curated collections of Psychiatric Services articles on:


American Psychiatric Association
The American Psychiatric Association, founded in 1844, is the oldest medical association in the country. The APA is also the largest psychiatric association in the world with 37,400 physician members specializing in the diagnosis, treatment, prevention and research of mental illnesses. APA’s vision is to ensure access to quality psychiatric diagnosis and treatment. For more information, please visit www.psychiatry.org.

Study reveals confusing mishmash of newborn bathing practices at US hospitals


Peer-Reviewed Publication

UNIVERSITY OF VIRGINIA HEALTH SYSTEM

Study reveals confusing mishmash of newborn bathing practices at U.S. hospitals 

IMAGE: "THE VARIATION IN WHAT HOSPITALS ARE DOING FOR NEWBORN SKINCARE IS A DIRECT RESULT OF PREVIOUSLY NOT HAVING A GOOD UNDERSTANDING OF WHAT REALLY IS THE BEST WAY TO CARE FOR A BABY'S SKIN," SAID RESEARCHER ANN L. KELLAMS, MD, OF UVA CHILDREN'S. "THE HOPE NOW IS THAT THIS WORK WILL CHALLENGE US ALL TO TAKE A LOOK AT THE EVIDENCE AND INCORPORATE PRACTICES THAT PROTECT BABIES THE MOST." view more 

CREDIT: DAN ADDISON | UVA COMMUNICATIONS

A nationwide survey of hospitals has revealed a wide variety of approaches to newborn skincare – including the timing of the first bath – that could ultimately have lasting effects on a baby’s health and wellbeing.

Believed to be the first of its kind, the survey sought to document newborn skincare practices at hospitals around the country. Doctors have increasingly come to appreciate the importance of infant exposure to natural skin microbes, but there are no clear evidence-based guidelines for hospitals to follow.

The result, the researchers found, is a mishmash of practices that sometimes break down along regional lines.

“The variation in what hospitals are doing for newborn skincare is a direct result of previously not having a good understanding of what really is the best way to care for a baby’s skin,” said researcher Ann L. Kellams, MD, of UVA Children’s. “The hope now is that this work will challenge us all to take a look at the evidence and incorporate practices that protect babies the most.”

Newborn Skincare: What’s Best for Baby?

The skincare babies receive in the hours and days after birth has long-term effects, shaping breastfeeding outcomes, infant skin health and even infection rates. For example, children who are birthed vaginally are known to have decreased rates of childhood allergies compared with those born by caesarian section.

That said, there is little hard evidence on health outcomes associated with delayed bathing and other newborn skin practices, such as the use of specific soaps and cleansers. That often leaves doctors with conflicting opinions, often built on anecdote and personal experience.

To get a sense of the practices in place around the country, the researchers sent 16 questions to nursery medical directors at 109 hospitals that are members of the Better Outcomes through Research for Newborns (BORN) network. The questions asked about bathing practices, the products used and the advice given to parents, among other topics.

The responses indicated:

  • 87% of hospitals delay the first bath by at least six hours. 
  • 10% send babies home without a bath, a practice more common in non-academic centers and on the West Coast. 
  • There is a huge variety of products and procedures used, though almost all include a “baby” soap containing detergents known to compromise the newborn’s skin integrity.
  • Bathing advice for parents, such as whether they should use soap when washing the baby, is “inconsistent and potentially contradictory” among healthcare providers. This can leave parents confused and uncertain what to do.

The evidence underpinning most hospitals’ skincare practices is “scant,” the researchers report in a new scientific paper outlining their findings. They are urging the formulation of more consistent guidelines built on hard evidence.

“Given the potential widespread clinical impact of newborn skincare and the paucity of data to support or refute widespread adoption of specific practices, further research is needed to improve and standardize care in U.S. nurseries and mother-baby units,” they state. 

COVID-19 guidelines may also be needed, they note. “Based on one large case series of maternal hospitals in New York City showing no increased morbidity to newborns, authors recommend that early skin-to-skin contact and delayed bathing can be practiced even in newborns born to mothers infected with COVID-19,” the researchers write.

Developing better, evidence-based guidelines in general would benefit all parents and infants, Kellams says. “In the future, we may be seeing a decreased emphasis on soap, an increased emphasis on oil-based cleansing and an increased emphasis on the application of emollients,” she said. “Better skin integrity would offer more protection to the babies against infection, development of allergies, etcetera.”

###

Findings Published

The researchers have published their findings in the scientific journal Hospital Pediatrics. The research team consisted of Julia A. Wisniewski, Carrie A. Phillipi, Neera Goyal, Anna Smith, Alice E.W. Hoyt, Elizabeth King, Dennis West, W. Christopher Golden and Kellams. The authors thank the members of the BORN network for their participation in the study.

To keep up with the latest medical research news from UVA, subscribe to the Making of Medicine blog at https://makingofmedicine.virginia.edu.