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Cuvier’s beaked whale records longest known dive lasting almost four HOURS

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cuviers beaked whale records longest known dive lasting almost four hours

A whale has stunned scientists by staying submerged underwater for almost four hours. 

The mammal belongs to the species Curvier’s beaked whale, which is known for their diving prowess. 

But the recorded dive time of 222 minutes is unheard of, and researchers estimate the animal’s oxygen reserves would have run out after just 77 minutes.   

Scientists are unable to explain how a mammal can be without oxygen for so long but believe the species can use anaerobic respiration for several hours, if necessary. 

As a result, Cuvier’s beaked whales likely have an exceptionally low metabolism, larger than usual oxygen stores and the ability to withstand stinging lactic acid.

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A Cuvier's beaked whale has stunned scientists by staying submerged underwater for almost four hours, a new record

A Cuvier's beaked whale has stunned scientists by staying submerged underwater for almost four hours, a new record

A Cuvier’s beaked whale has stunned scientists by staying submerged underwater for almost four hours, a new record 

Scientists are unable to explain how a mammal can be without oxygen for so long but believe the species can use anaerobic respiration for several hours, if necessary

Scientists are unable to explain how a mammal can be without oxygen for so long but believe the species can use anaerobic respiration for several hours, if necessary

Scientists are unable to explain how a mammal can be without oxygen for so long but believe the species can use anaerobic respiration for several hours, if necessary

Previous calculations suggest these relatively diminutive whales should only remain submerged for about 33 minutes before their oxygen runs out.

At this point they switch to anaerobic respiration, a process done without oxygen which is less efficient and produces lactic acid. 

Lactic acid is the same burning feeling in muscles people experience after prolonged or strenuous exercise. 

However, researchers in the latest study refined this calculation and believe anaerobic respiration begins 77.7 minutes into a dive. 

Researchers from Duke University in North Carolina tried to record some dives from this remarkable and little-known species. 

This task was made tricky by the fact the whales spend less than two minutes at the surface after completing one of their dive, making the act of sticking a tag on a dorsal tricky. 

A total of 23 tags were added to individual whales in the waters off Cape Hatteras, USA, recording more than 3,600 dives.

Researchers in the latest study believe anaerobic respiration begins 77.7 minutes into a dive, more than double the previous estimate of 33 minutes

Researchers in the latest study believe anaerobic respiration begins 77.7 minutes into a dive, more than double the previous estimate of 33 minutes

Researchers in the latest study believe anaerobic respiration begins 77.7 minutes into a dive, more than double the previous estimate of 33 minutes 

Tthe two longest dives were recorded in 2017 at 222 and 173 minutes. These were not included in the dataset because the dives occurred just 24 and 17 days after a one hour exposure to a Navy sonar signal, respectively.

Tthe two longest dives were recorded in 2017 at 222 and 173 minutes. These were not included in the dataset because the dives occurred just 24 and 17 days after a one hour exposure to a Navy sonar signal, respectively.

The two longest dives were recorded in 2017 at 222 and 173 minutes. These were not included in the dataset for the study because the dives occurred just 24 and 17 days after a one hour exposure to a Navy sonar signal, respectively

How and why do Cuvier’s beaked whales dive for so long?  

Cuvier’s beaked whales are described as the ‘true megastars’ of the diving world.

Researchers say they are capable of reaching depths of almost 3,000 metres (1.86 miles).

Adults measure up to 7m (23 ft) long and weigh up to 3,000 kg (6,600 lbs). 

Cuvier’s have a cone-shaped head, with a stubby beak and the short mouth-line curves upwards and looks like a smile.

The torpedo-shaped body is grey due to algae and appears to be highly scarred. This is caused either by fights with other males and the unique oval marks are caused by cookie-cutter sharks.

They live in waters all around the world, except for around Antarctica and the Arctic, and eat fish and squid from deep in the ocean. 

They spend very little time o the surface between dives, often less than two minutes before submerging again.  

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It revealed the shortest dive was 33 minutes. Experts know 95 per cent of all dives, from all marine mammals, are completed before the oxygen runs out.  

Using the data from the 3,680 dives, the 95 per cent threshold puts the onset of anaerobic respiration — the point where oxygen reserves have been depleted — at 77 minutes.

However, the two longest dives were recorded in 2017 at 222 and 173 minutes.

These were not included in the dataset because the dives occurred just 24 and 17 days after a one hour exposure to a Navy sonar signal, respectively. 

As whales use echolocation to communicate and direct themselves, this may have triggered an unusual response in the animal leading to unusually elongated dives. 

However, the researchers say in the study that these extraordinarily long dives are ‘perhaps more indicative of the true limits of the diving behaviour of this species’.

Their ability to stay submerged for so long can only be explained by an unrivalled ability to tolerate anaerobic respiration. 

‘It really did surprise us that these animals are able to go so far beyond what predictions suggest their diving limits should be’, says Dr Nicola Quick, who led the study. 

Referring to the exceptionally long dive of three hours and 42 minutes, Dr Quick said: ‘We didn’t believe it at first; these are mammals after all, and any mammal spending that long under water just seemed incredible.’ 

The findings were published in the Journal of Experimental Biology.

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Nature: Ogre-faced spiders can hear without ears via their hairy legs

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nature ogre faced spiders can hear without ears via their hairy legs

The hairy legs of the ogre-faced spider allow it to hear sound vibrations from up to six feet away — even though it has no actual ears — a study has found.

Experts from the US found that the arachnids — named for their massive eyes, which provide great night vision — can pick up on both low and high frequency sound.

Their legs — and the joint receptors within — pick up on the vibrations, letting them perform feats like catching prey outside of their vision using backwards strikes.

Ogre-faced spiders — formally known as Deinopis spinosa — can be found in Australia, America and Asia.

The hairy legs of the ogre-faced spider, pictured, allow it to hear sound vibrations from up to six feet away — even though it has no actual ears — a study has found

The hairy legs of the ogre-faced spider, pictured, allow it to hear sound vibrations from up to six feet away — even though it has no actual ears — a study has found

The hairy legs of the ogre-faced spider, pictured, allow it to hear sound vibrations from up to six feet away — even though it has no actual ears — a study has found

‘I actually put dental silicone over their eyes so they couldn’t see,’ said paper author and neuroethologist Jay Stafstrom of Cornell University, in Ithaca, New York.

‘And I found that when I put them back out into nature, they couldn’t catch prey from off the ground, but they could still catch insects from out of the air.’

‘So I was pretty sure these spiders were using a different sensory system to hunt flying insects.’

Instead of spinning a web and waiting for prey to get stuck in it, ogre-faced spiders emerge at night to cast their webs — like a thrown net — onto unwary insects.

While they employ their superb night vision to catch prey on the ground, in the air they are able to perform an elaborate backwards strike — one which does not appear to rely on vision in order to be effective.

In lab tests, Dr Stafstrom and colleagues used electrodes placed in the spiders’ brains and legs to measure the arachnids’ neural responses to different tones.

The researchers found that the spiders could hear both low and high tone frequencies — reacting differently to each.

In fact, they determined that the ogre-faced creepy crawlies can hear sounds of up to 10 kilohertz in frequency — far higher than the sound of a walking or flying insect. 

‘When I played low tone frequencies — even from a distance — they would strike like they were hunting an insect, which they don’t do for higher frequencies,’ explained Dr Stafstrom.

‘And — the fact that we were able to do that from a distance, knowing we’re not getting up close and causing them to vibrate — that was key to knowing they can really hear,’ he added. 

Instead of spinning a web and waiting for prey to get stuck in it, ogre-faced spiders emerge at night to cast their webs — like a thrown net — onto unwary insects. While they employ their superb night vision to catch prey on the ground, in the air they are able to perform an elaborate backwards strike (illustrated) — one which does not appear to rely on vision

Instead of spinning a web and waiting for prey to get stuck in it, ogre-faced spiders emerge at night to cast their webs — like a thrown net — onto unwary insects. While they employ their superb night vision to catch prey on the ground, in the air they are able to perform an elaborate backwards strike (illustrated) — one which does not appear to rely on vision

 Instead of spinning a web and waiting for prey to get stuck in it, ogre-faced spiders emerge at night to cast their webs — like a thrown net — onto unwary insects. While they employ their superb night vision to catch prey on the ground, in the air they are able to perform an elaborate backwards strike (illustrated) — one which does not appear to rely on vision

‘I think many spiders can actually hear, but everybody takes it for granted that spiders have a sticky web to catch prey, so they’re only good at detecting close vibrations,’ said paper author and neurobiologist Ron Hoy of Cornell University.

‘Vibration detection works for sensing shaking of the web or ground, but detecting those airborne disturbances at a distance is the province of hearing.’

This, he added, ‘is what we do and what spiders do too, but they do it with specialized receptors, not eardrums.’

Hearing high frequencies may help the spiders avoid predators, the team explained.

‘If you give an animal a threatening stimulus, we all know about the fight or flight response. Invertebrates have that too, but the other “f” is “freeze.” That’s what these spiders do,’ said Professor Hoy.

‘They’re in a cryptic posture. Their nervous system is in a sleep state. But as soon as they pick up any kind of salient stimulus, boom, that turns on the neuromuscular system. It’s a selective attention system.’ 

'I think many spiders can actually hear, but everybody takes it for granted that spiders have a sticky web to catch prey, so they're only good at detecting close vibrations,' said paper author and neurobiologist Ron Hoy of Cornell University

'I think many spiders can actually hear, but everybody takes it for granted that spiders have a sticky web to catch prey, so they're only good at detecting close vibrations,' said paper author and neurobiologist Ron Hoy of Cornell University

‘I think many spiders can actually hear, but everybody takes it for granted that spiders have a sticky web to catch prey, so they’re only good at detecting close vibrations,’ said paper author and neurobiologist Ron Hoy of Cornell University

Ogre-faced spiders, pictured — formally known as Deinopis spinosa — can be found in Australia, America and Asia

Ogre-faced spiders, pictured — formally known as Deinopis spinosa — can be found in Australia, America and Asia

Their legs — and the joint receptors within — pick up on the vibrations, letting them perform feats like catching prey outside of their vision using backwards strikes.

Their legs — and the joint receptors within — pick up on the vibrations, letting them perform feats like catching prey outside of their vision using backwards strikes.

Ogre-faced spiders, pictured — formally known as Deinopis spinosa — can be found in Australia, America and Asia. Their legs — and the joint receptors within — pick up on the vibrations, letting them perform feats like catching prey outside of their vision using backwards strikes.

With their initial study complete, the researchers are now looking to test to what extent the ogre-faced spiders have directional hearing — that is, the ability to tell exactly what direction a sound is coming from.

This ability could well explain how the arachnids can perform their acrobatic backwards hunting strikes without being able to see where they are going.

‘What I found really amazing is that to cast their net at flying bugs they have to do a half backflip and spread their web at the same time, so they’re essentially playing centerfield,’ added Professor Hoy.

‘Directional hearing is a big deal in any animal, but I think there are really going to be some interesting surprises from this spider.’

The full findings of the study were published in the journal Current Biology

IS A FEAR OF SPIDERS IN OUR DNA? 

Recent research has claimed that a fear of spiders is a survival trait written into our DNA.

Dating back hundreds of thousands of years, the instinct to avoid arachnids developed as an evolutionary response to a dangerous threat, the academics suggest.

It could mean that arachnophobia, one of the most crippling of phobias, represents a finely tuned survival instinct.

And it could date back to early human evolution in Africa, where spiders with very strong venom have existed millions of years ago.

Study leader Joshua New, of Columbia University in New York, said: ‘A number of spider species with potent, vertebrate specific venoms populated Africa long before hominoids and have co-existed there for tens of millions of years.

‘Humans were at perennial, unpredictable and significant risk of encountering highly venomous spiders in their ancestral environments.’

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NHS Covid-19 app finally gets an update to stop ‘confusing’ ghost notifications

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nhs covid 19 app finally gets an update to stop confusing ghost notifications

The NHS Covid-19 app has finally received an overdue update to stop users receiving confusing ‘ghost notifications’.

After the app was launched on September 24 it has been downloaded more than 19 million times by people in England and Wales, with 40 per cent of smartphone users installing the app. 

The Department of Health and Social Care also says the update will feature upgrades to how accurate the app is at detecting other users. 

As a result of this and soaring infection rates, more people will be told to self-isolate by the app as the threshold for being deemed a close contact has been lowered.  

Yesterday, Britain announced 24,701 more infections and a further 310 coronavirus victims, up from the 191 posted this time last week.

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Pictured, the notification which will follow one of the so-called 'phantom alerts'. This workaround is designed to quash any concern users may have after receiving the initial notification

Pictured, the notification which will follow one of the so-called 'phantom alerts'. This workaround is designed to quash any concern users may have after receiving the initial notification

Pictured, the notification which will follow one of the so-called ‘phantom alerts’. This workaround is designed to quash any concern users may have after receiving the initial notification 

Many users were getting alerts which were 'default messages' from Apple and Google, saying 'Possible COVID-19 exposure', 'COVID-19 EXPOSURE LOGGING' or 'COVID-19 Exposure Notifications'. Pictured, an example of the phantom notification which was sent out last week

Many users were getting alerts which were 'default messages' from Apple and Google, saying 'Possible COVID-19 exposure', 'COVID-19 EXPOSURE LOGGING' or 'COVID-19 Exposure Notifications'. Pictured, an example of the phantom notification which was sent out last week

Many users were getting alerts which were ‘default messages’ from Apple and Google, saying ‘Possible COVID-19 exposure’, ‘COVID-19 EXPOSURE LOGGING’ or ‘COVID-19 Exposure Notifications’. Pictured, an example of the phantom notification which was sent out last week 

The app uses bluetooth in the background and anonymously works out if you are likely to have been in contact with someone who tested positive for the coronavirus. 

If they have, people receive a notification from the app telling them they must self-isolate.

However, in the five weeks since it went live users have been receiving mysterious notifications that say ‘COVID-19 EXPOSURE LOGGING’ or ‘COVID-19 Exposure Notifications’.

London’s R rate ‘is the worst in England’ 

Coronavirus is spreading fastest in London, according to a study that claims the R rate in the capital is almost as high as three and infections are doubling every three days.

Researchers at Imperial College London, who today estimated a staggering 100,000 people are catching Covid-19 every day across the country, warned the city has a ‘scary’ rate of spread. For comparison, the experts claimed the national R rate is around 1.6 and cases are doubling every nine days.

They predicted the R rate — the average number of people each carrier infects — is higher than two in London, the South East, East and South West, which have mostly escaped any tough local lockdowns. And of the entire south of England, London has the highest prevalence of coronavirus at 0.89 per cent, suggesting more than 80,000 of the city’s nine million residents were infected at any given moment.

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Despite causing fear, they were not a warning of infection and were instead revealed to be default notifications from Apple or Google, who built the app framework.

A quick solution was quietly rolled out on October 13 which sent another notification telling users ‘Don’t worry, we have assessed your risk and there is no need to take action at this time.’ 

Now, the NHS has finally admitted the glitch was confusing and the fix was ‘still an inconvenience and cause for concern for some app users.’ 

The update will do away with these misleading and worrisome notifications all together. 

Gaby Appleton, product director at NHS Test and Trace, said: ‘This update builds on that success by increasing accuracy, and also removing ‘ghost’ exposure notifications, meaning users will only be notified if they need to self-isolate.

‘The more people who use the app, the better it works, so I encourage all those who have not yet downloaded the app to do so.’

Another update to the app is a lowering of the threshold for alerts. 

This means the criteria for being deemed a close contact of an infected person is now easier to meet and more people will be asked to self-isolate as a result. 

Previously, the checklist was being within two metres of an infected person for at least 15 minutes. 

According to the Department of Health and Social Care, this was a score of 900 on its own algorithm. 

However, this threshold will now be lowered to 120. It remains unknown what a 120 score from the algorithm means in reality.  

Other updates are imminent, according to the Department of Health and Social Care, with a November patch intended to allow the NHS app to work seamlessly with users of the separate versions made and used in Scotland, Northern Ireland, Jersey and Gibraltar. 

Leaked SAGE projections made in the summer suggest that under a 'reasonable worst case scenario' daily deaths could remain above 500 for three months or more, potentially lasting into March next year

Leaked SAGE projections made in the summer suggest that under a 'reasonable worst case scenario' daily deaths could remain above 500 for three months or more, potentially lasting into March next year

Leaked SAGE projections made in the summer suggest that under a ‘reasonable worst case scenario’ daily deaths could remain above 500 for three months or more, potentially lasting into March next year

How the NHS Covid-19 app works and the reasons behind some of its flaws

 The NHS contact tracing coronavirus app , called NHS Covid-19, is based on  a piece of software, an API, built by tech giants Apple and Google, who came together in an unprecedented alliance at the start of the pandemic.

It works via Bluetooth, which is fitted to almost every smartphone in the world, and involves a notification system to alert people if they have been in close proximity with someone diagnosed with Covid-19.

Apple and Google let the NHS determine what it deems to be suitable exposure for a a person to be considered at risk for infection. 

The NHS set the limit as within 2m for 15 minutes. 

However, Apple and Google have openly said the app is not perfect, due to the fact Bluetooth is being used for something it was never designed for. 

Therefore, phones with the app installed can struggle to tell exactly how far away another device is. 

Although the threshold is set at 2 metres, it emerged in early trials that people as far away as 4m were told thought by the technology to be less than 2m away. 

Officials say that about 30 per cent of people told to self-isolate may have been more than two metres away from a positive case.

However, they claim most of these cases will be at a distance of 2.1m or 2.2 m, with 4m being a rarity.  

Apple and Google have been aware of this issue since the inception of the project and have recently revealed they have used hundreds of different devices to help calibrate the system. 

It is claimed the NHS app is more accurate than other contact tracing apps around the world which also use the Apple and Google API. 

All the technology for the app is done in the phone itself, and no external servers are used, helping protect user data.

No location or personal data is sent to Apple, Google or the NHS and all interactions between phones are anonymous.

The randomised and untraceable links are only stored for two weeks on the phone itself before being permanently deleted. 

A person can also choose to wipe their data clean, either in the app’s settings or by deleting the app.  

In a conference call this week, representatives from both Google and Apple said the app is not intended to replace manual tracing, but to enhance it. 

33521810 8819107 image a 12 1602161375192

33521810 8819107 image a 12 1602161375192

They added that, in the tests done in-house during development, 30 per cent of the exposure notifications that were triggered were not picked up by manual contact tracing. 

For a person to receive am infection notification via the app, both they and the infected person must both have had the app at the time of their interaction.

During this interaction, on a bus for example, the phones acknowledge the device has met the 2m/15 min criteria. 

The devices then automatically exchange anonymous ‘keys’ with each other via Bluetooth. The keys randomise and change approximately every 15 minutes. 

If a person then receives a positive test, they receive a unique PIN from the NHS and input this in the app. 

Once they have done this, all the anonymised keys from the phone of the infected person are added to a cloud database. 

Every app is constantly checking in with the same cloud database to see is any of the ‘keys’ it has come into contact with match the keys of positive tests. 

If a person’s phone finds a match, that person then receives a notification informing them they have been exposed and may be infected. 

The app then provides that person with detailed information from the NHS on the next steps. 

The mobile data needed for the app to work is being allowed free of charge in the UK by network carriers and it is believed the app has negligible impact on battery life.    

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Good teacher-pupil relationships can help mental heath later on, study claims

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good teacher pupil relationships can help mental heath later on study claims

Teenagers who have a good relationship with their teachers at school go on to have better physical and mental health as adults, a new study has found. 

Based on a 13-year study of 20,000 people, Korean researchers discovered a link between good parent-teacher relationships when they were at school and positive wellbeing when they were in their mid-20s.   

Teachers who foster good relationships with their pupils can have a longer lasting effect than they may even realise, beyond academic achievement. 

Although friendships at school are important, researchers did not find the same link between good peer relationships and students’ health in adulthood. 

Teenagers who have a great relationship with their teachers benefit from better health later in life, according to a new study.

Teenagers who have a great relationship with their teachers benefit from better health later in life, according to a new study.

Teenagers who have a great relationship with their teachers benefit from better health later in life, according to a new study.

‘This research suggests that improving students’ relationships with teachers could have important, positive and long-lasting effects beyond just academic success,’ said study author Jinho Kim at Korea University. 

‘It could also have important health implications in the long run.’

Schools should invest in training teachers on how to build warm and supportive relationships with their students, according to Kim.

‘This is not something that most teachers receive much training in but it should be,’ he said.   

Previous research has mostly focused on teens’ relationships with their peers, rather than on their relationships with teachers. 

To learn more about teacher-pupil relationships, Kim analysed data on nearly 20,000 participants from the US’s long-term Add Health study.

Add Health is a nationally representative longitudinal study in the US that followed participants for 13 years, from seventh grade into early adulthood. 

The participant pool for the study included more than 3,400 pairs of siblings, so Kim could control for family background factors such as genetics, neighborhood and the effect of a family household.  

Previous research has mostly focused on teens' relationships with their peers, rather than on their relationships with teachers

Previous research has mostly focused on teens' relationships with their peers, rather than on their relationships with teachers

Previous research has mostly focused on teens’ relationships with their peers, rather than on their relationships with teachers 

As teens, participants answered questions such as, ‘How often have you had trouble getting along with other students?’, ‘How much do you agree that friends care about you?’ ‘How often have you had trouble getting along with your teachers?’ and ‘How much do you agree that teachers care about you?’ 

As adults, participants were asked about their mental health as well as physical health, which was based on measures of blood pressure and body mass index. 

Participants who had reported better relationships with both their peers and teachers in middle school and high school also reported better physical and mental health in their mid-20s, Kim found. 

When looking at the pairs of siblings together, the link between good teacher relationships and adult health remained significant. 

Previously reported links between peer relationships and physical health could actually reflect other, underlying factors about students’ family background, Kim claimed, because studies did not control for these factors.   

Previous research has suggested that teens’ social relationships might be linked to health outcomes in adulthood, perhaps because poor relationships can lead to chronic stress, which can raise a person’s risk of health problems over the lifespan. 

However, it had not been clear whether the link between teen relationships and lifetime health was causal – that the former directly caused the latter. 

It could be that other factors, such as different family backgrounds, might contribute to both relationship problems in adolescence and to poor health in adulthood.   

The study has been published in the journal School Psychology.    

HOW CAN TEACHERS FOSTER POSITIVE RELATIONSHIPS WITH PUPILS 

The following are the dos and don’ts for teachers to foster good relationships with their pupils, as listed by the American Psychological Association. 

Do:

– Make an effort to get to know and connect with each student in your classroom. Always call them by their names, find out information about their interests and strive to understand what they need to succeed in school.

– Make an effort to spend time individually with each student, especially those who are difficult or shy. This will help you create a more positive relationship with them.

– Be aware of the explicit and implicit messages you are giving to your students. Be careful to show your students that you want them to do well in school through both actions and words.

– Create a positive climate in your classroom by focusing not only on improving your relationships with your students, but also on enhancing the relationships among your students.

Don’t:

– Don’t assume that being kind and respectful to students is enough to bolster achievement. Ideal classrooms have more than a single goal: teachers hold students to appropriately high standards of academic performance and offer students an opportunity for an emotional connection to their teachers, their fellow students and the school.

– Don’t give up too quickly on your efforts to develop positive relationships with difficult students. These students will benefit from a good teacher-student relationship as much or more than their easier-to-get-along-with peers.

– Don’t assume that respectful and sensitive interactions are only important to elementary school students. Middle and high school students benefit from such relationships as well. 

– Don’t assume that relationships are inconsequential. Some research suggests that preschool children who have a lot of conflict with their teachers show increases in stress hormones when they interact with these teachers.

– Don’t wait for negative behaviors and interactions to occur in the classroom. Instead, take a proactive stance on promoting a positive social experience by including students in discussions about prosocial interactions and consistently modeling those positive interactions for them. 

Source: American Psychological Association 

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