Smart prosthetic hand combines both human and robot control

Zhuang et al. Shared human–robot proportional control of a dexterous myoelectric prosthesis. Nature Machine Intelligence, September 2019.

Holding an object in your hand might seem easy, but it’s actually a very complicated and challenging task; if, for instance, an object starts to slip, you typically have a couple of milliseconds to react. Scientists have been trying new approaches for improved control of robotic hands, particularly for use by amputees. A recent technology was able to combine individual finger control and automation for improved grasping and manipulation by successfully merging the fields of neuroengineering and robotics. This interdisciplinary approach was tested on three amputees and seven non-amputee subjects. The neuroengineers achieved the intended finger movement from muscular activity on the amputee’s stump, allowing for individual finger control of a prosthetic hand, which had never been done before. The robotics team enabled the robotic hand to take hold of objects and maintain contact with them for robust grasping. The amputee first performed a series of hand movements in order to train the algorithm through a machine learning paradigm. This taught the algorithm to decode user intention and translate it into finger movements of the prosthetic hand. Concurrently, sensors placed on the amputee’s stump detected muscular activity, which trained the algorithm to learn which hand movements corresponded to which patterns of muscular activity. Once the user’s intended finger movements were acquired, this information could then be used to control individual fingers on the prosthetic hand. When the user tried to grasp an object, the robotic automation initiated. The algorithm told the prosthetic hand to close its fingers when an object was in contact with sensors on the hand’s surface. This automatic grasping was designed to infer the shape of objects and grasp them based on tactile information alone, without any help of visual signals. The robotic hand has the ability to react within 400 milliseconds, and it is equipped with pressure sensors all along the fingers: it can react and stabilize the object before the brain can actually perceive that the object is slipping. While this promising technology can be used in in several neuro-prosthetic applications such as bionic hand prostheses and brain-to-machine interfaces, there are still many challenges remaining to implement this technology in a commercially available prosthetic hand for amputees. It is currently being tested and improved.

Cats securely bond with people, too

Vitale et al. Attachment bonds between domestic cats and humans. Current Biology, September 2019.

Dogs have long been regarded as man’s best friend. They’re sociable, faithful, and obedient. Cats, on the other hand, are often described as more aloof, mysterious, and independent. But a new study suggests that cats actually bond with their owners in similar ways to how humans and dogs bond with companions. The most established way to study human attachment behavior is to observe an infant’s response to a reunion with their caregiver following a brief absence in a novel environment. When a caregiver returns, secure infants quickly return to relaxed exploration while insecure individuals engage in excessive clinging or avoidance behavior. These tests had been previously run with humans, primates, and dogs; researchers decided to run the same test with cats. 79 kittens and 38 adult cats and their caregivers were recruited. During the test, an adult cat or kitten spent two minutes in a novel room with their caregiver followed by two minutes alone. Then, they had a two-minute reunion. The cats’ responses to seeing their owners again were classified into attachment styles. The results show that cats bond in a way that’s surprisingly similar to infants. In humans, 65% of infants are securely attached to their caregiver and domestic cats and kittens mirrored this, as about 65% of them securely bonded to their people. After the first round of tests, the researchers enrolled half the kittens used in the study in a training and socialization course. The other half served as a control group. Researchers then found the same results, suggesting the training did not have an effect on kittens’ attachment behavior toward their owners. This indicates that once a cat forms a bond, it seems to remain stable over time. This social flexibility may have helped facilitate the success of the species in human homes. It is still not clear what the factors are that shape the caretaker relationship, but it’s likely a miraculous complex mix of genetics, personality, and experience.

An efficient and green way to convert heat into electricity

Zheng et al. Paramagnon drag in high thermoelectric figure of merit Li-doped MnTe. Science Advances, September 2019.

A recent discovery could help scientists to develop more efficient ways to generate electricity from heat that would have been otherwise wasted, such as heat coming from car exhaust, industrial processes, and interplanetary space probes. In principle, magnetic fields can be used to generate electricity. If we move a magnet through a coil or wire, the magnet pushes and pulls electrons that create an electrical current. Magnets themselves don’t have energy, but they can control energy currents through the created magnetic field. The main problem with magnets is that when a magnet is heated up, it loses most of its magnetic properties and becomes a so-called paramagnet. Until this discovery, scientists believed that paramagnets couldn’t be used for generating electricity. In the new study, researchers found a way of designing thermoelectric semiconductors that can convert heat to electricity. The tiny particles in paramagnets, so called paramagnons, ended up producing enough spin to push an electron, for only a billionth of a millionth of a second – apparently long enough to make paramagnets viable energy-harvesters. This breakthrough in the conventional understanding of magnetic properties could lead to more research into how magnets and energy interact to potentially facilitate electricity production from heat that is otherwise wasted and oftentimes harmful to the environment.

Cats are born with their eyes closed and no sense of hearing, but they improve their abilities over time. Their sense of vision develops every day and babies require approximately five months to be able match the visual capabilities of an adult cat. To augment their abilities, kittens have incredible senses of smell.

This can be witnessed when kittens are fed by their mother. A mother cat designates a nipple for each baby. When kittens that seem to be fighting each other during nursing are observed carefully, one can see that each newborn is trying to reach their own designated nipple. They find it through their incredible sense of smell.

As mentioned above, though cats are friendly, they will occasionally misbehave. This naughtiness hints that their predatory instincts are still intact. The development of their hunting ability is honed through games and aided by the fact that kittens do not have feelings of fear before they are six weeks old. During this short time, they are required to obtain sufficient experience to survive. When they are one year old, a cat will have all their adult characteristics.

One defining trait of cats is their flexibility. Cats have 40 more bones than humans and this enables them with such flexibility. Most of these bones are located in the spine and tail sections. The advanced flexibility of the lumbar bones provides cats with agility. The disks positioned in between vertebrae are tighter than the disks of human vertebra. This feature naturally enables cats to move uniquely and flex their body up to 11%.

This also means that when a cat encounters prey, it can estimate the distance at a glance and can jump 1.5 meters without needing any speed. The human equivalent would be jumping 8.5 meters without a running start. Another aspect of this flexibility is that cats can go through any opening that their heads fit through because they lack a clavicle. They also have powerful legs and their paws are created in a way to contract within a fraction of a second upon landing. Their retractable claw acts as a hook when protruded completely and permits them to climb and grasp vertical surfaces.

We often overlook cats. They’re pets and companions. But in truth, they’re so much more. Blessed with some incredible traits, cats are actually marvels of creation.

Animals with nine lives!

When falling, cats open their legs sideways to generate a parachute effect. By doing this, they control their speed to prepare for a soft landing and land on their feet with remarkable reflexes. A fluid in their inner ear moves when they are not in balance and they develop a reflex to help them land on their paws. There is one problem: they cannot relax their muscles completely when falling from places that are not high enough, disabling the parachute effect. The risk of injury for cats is lower if they fall from the thirty-second floor (100 m) than if they fall from the seventh floor, experiments have shown.

Sensing earthquakes

Cats have many senses that are significantly stronger than human senses. Sight and hearing, which are required for hunting and survival, are the two basic senses more advanced than the rest. Every sound they hear feels very powerful. For instance, the tic-tac sounds of a clock are four times stronger to cats than to humans. Cats are granted the skill to distinguish high frequency sounds that humans and even dogs cannot notice. This skill enables them to separate between the voices of people. In addition, there are more than 20 muscles in a cat’s ear. This enables the independent movement and control of each ear. Thus they can determine the source of sound with speed and precision, and detect the exact location of prey from just a small movement in one-sixteenth of a second.

These cute animals are skilled at feeling the weakest vibrations. With this skill, cats are considered to have the ability to feel earthquakes a couple of days in advance, like some other animals, though it is not exactly understood how this occurs. It is possible that these animals can even sense vibrations too small to be captured by measuring systems. Despite all the efforts of scientists, they struggle to forecast the timing of earthquakes even with modern technological devices. However, many animal species display abnormal behaviors hours and even days before an earthquake. This remains a mystery how animals react in such a way. Therefore, data acquired with detailed studies performed on animals will surely provide many benefits in terms of accurate prediction of earthquakes.

A cat’s eye

Cat’s eyes are also created in a fashion to let them focus on their prey. Sharp vision is as important as the sense of hearing for a night hunter. During hunting, the target is in focus and everything else is blurry. Cat’s eyes, when compared to human eyes, contain many extra cells in charge of sensing light, including a crystal layer behind the retina that absorbs all available but unused light. Like other nocturnal animals, cats have the layer called “tapetum lucidum” in their eyes. This layer reflects light like a mirror, and for this reason, cat’s eyes shine in darkness. This reflection effect even permits cats to utilize the lowest level of light possible. The iris can adjust its width depending on the light’s strength, just like the diaphragm of a camera; this allows cats to distinguish their surroundings in the dark. Another feature of Tapetum lucidum is that when light strikes a cat’s eye from an angle, it causes the eye to shine, even in dim light.

There are limits to cat’s night vision powers – and they make up for this with their whiskers. A cat’s whiskers enable them to sense the slightest changes in the air. These facial hairs work like a radar system, helping them to identify the outline of objects that they barely see.

Sensing fear

The one sense cat’s lack when compared to humans is their sense of taste. Cat tongues have 25% less papillae (taste buds) than human tongues; they do not enjoy sugary foods. The pleasure these animals get from eating is related to another sense granted to them in addition to smell and taste. Cats have an organ located at the frontal section of their palate which is lacking in humans. It’s called the Jacobson organ. Chemical signals enter the mouth and end up in a small capsule after passing through the opening in between two palates located behind the front teeth. These chemical cues are stored here. This means that they can taste chemical signals. Even though it is not possible for cats to compete with dogs in terms of olfactory senses, this ability is fourteen times more powerful than human’s sense of smell. This skill is used for social communication. It’s likely that cats recognize people through their scents. While a human nose houses only 5 million olfactory cells, there are around 200 million sensory cells placed in the small noses of cats. A significant portion of their brain is ready to sense, assess, and respond properly to chemical signals.

Tidy animals

Cats dedicate a major portion of their time to cleaning. These animals truly enjoy their cleaning sessions. It takes a long time to fix their tangled fur. In addition, their fur must be bright and well cleaned in order to protect their body against exposure to external elements like cold air and rain. Cats lick their paws to use them like gloves to clean their faces. Their tongue is long and there are small projections found in the rear section. This section, rich in buds, acts like a brush and enables them to better clean their fur. The tongue triggers the oil glands at the base of each hair. A fluid is secreted that makes a cat’s fur waterproof.

Despite their fur, cats do not get heat exhaustion. The hairs not only prevent them from feeling intense heat, but also keep them warm by insulating them from the surrounding environment. These animals also display strong resistance to pain. This results from their high levels of endorphin, the hormone for pain reduction.

Sleeping beauties

Cats spend 2/3 of their lives sleeping. Therefore they are often used as experimental animals for sleep-related research. It is possible to say that we owe most of the information regarding sleep mechanisms and the effects of sleep to cats.

Natural navigation

Cats are created with the perfect tool for navigation. Experiments have shown that they can cover miles of road to return back to their home. It is thought that these animals find their way by employing the sun and the Earth’s magnetic field. What is hard to explain is how they happen to find a new house when their owners move. It is still unknown whether this skill originates from a certain sensory mechanism or whether cats are provided with even sharper senses than we think they have. Whatever the answers may be for these questions, we can simply conclude that cats are animals which have been truly blessed in a way that allows them to adapt to their environments.

Sight: When we look around, we see several shades of colors and hundreds of thousands of images. Human beings, and several animals, are able to see images when light enters the eye and releases an electrical signal through our the nerves to the brain. These signals are then transformed into the images, or pictures, that we see. All creatures see these images differently; some see images in different outlines in shape, color, clarity, circumstances, and distance.

Dogs, because of their hunting needs, see twice as much as do human beings. In addition, dogs have an outstanding ability to follow movement and to perceive direction, speed, and trajectory. Trajectory is what gives dogs the innate ability to plot an angle and predict an angle of movement. For example, dogs have an astonishing ability to know the exact spot where a moving object will land and know from which angle it will be coming. This is the reason why dogs are such good ball and Frisbee catchers; because they visually know the exact point of impact of an object as it falls back to the ground. Cats, on the other hand, have a different reason for being such good jumpers. Cats’ faces are flat between the eyes, a rare feature in the animal world, which makes it easier for them to work together. As a result, a cat can focus sharply and three-dimensionally, an ability that allows it to visually judge distances with great accuracy before jumping.

Rabbits, for example, are one of the few animals that can see all around them (front and back) without turning in either direction. Their eyes are located on the sides of their head, which enables them to see in all directions. Rabbits, frequent preys for predators, are always on the alert, and their eyes are located in the best place to help them see their enemies.

Human beings and wildlife animals have two kinds of vision cells that are located inside the back of the eye: cones and rods. Cones detect colors in bright light, including black, white, and gray. Rods provide sharp vision in dim light, but do not detect colors. Night creatures have more rods than cones, which provide them with sharper vision at night-but with only shades of gray. Also, to assist these creatures in the dark, they have a special layer in the back of their eyes, called the tapetum, which acts as a mirror when light passes through it. If the rod does not detect the light during the first passing, the tapetum reflects the light back to the rod, thus giving the rod a second chance to pick up on the light and see an image. It is this layer that makes some animal’s eyes shine in dim light.

An owl’s eye, for example, is so sensitive in picking up light, that research shows that an owl can follow a trial lit up by a candle 1,000 feet away (3,600 meters).1

Another amazing sight feature is found in predator birds: “telescopic” eyes that allow them to see by making a far away distant object appear larger. Birds such as the hawk and eagle have the sharpest sight of any animal. These birds have about 1.04 million vision cells in the back of their eyes, which that enables them to see a mouse from as far as one mile away.2 (Human beings have only about 130 million vision cells.)3

Although animals are believed to see colors similar to the way humans do, scientists are not sure how bees and insects see color. Scientists believe that, among some other creatures, bees, birds, and insects can see a color that human beings can not: ultraviolet colors. In addition to red, blue, and yellow, flowers often have ultraviolet patterns that show these birds and insects the way to the plant’s nectar and pollen. Such sight makes it possible for these creatures to find and feed on the flowers’ nectar and pollen.

However, not all animals have only two eyes. Jumping spiders, for instance, have eight eyes. There are two big eyes in the front, and six smaller eyes on the top of the head slightly toward the sides. The two front eyes are very well developed and act as a pair of binoculars that give the spider a clear image of objects up to one foot (30 cms) away. The little eyes are called secondary eyes. These eyes can spot moving objects and have a built-in reflecting layer that helps the spider to see objects in dim light. The secondary eyes are the eyes that actually measure the distance the spider needs to jump to catch its prey.

Hearing: Just as with other senses, human beings and animals have different levels of hearing. Most animals have only two ears, which helps all of us locate the origin of a sound. Having two ears helps us locate where a sound comes from. Since sound reaches the ears at slightly different times, this makes a sound louder than in one ear. This difference in volume and arrival time in one ear is an indication as to the origin of the sound. Sound is expressed in hertz (cycles per second), which are repetitive vibrations per second. Adult human beings, with a normal hearing ability, can hear from twenty to twenty thousand cycles per second. Amazingly, wolves can hear up to eighty thousand cycles per second, and dogs can hear up to thirty-five thousand cycles per second, almost twice as many as humans.

Cats have a surprising hearing of between fifty to one hundred thousand cycles per second-three to five times than what human beings can hear. In addition, a cat’s ear has thirty muscles that control the ear muscles that can rotate 180 degrees. This give cats the opportunity to hear its surroundings without moving its head.

An owl’s ear, however, are located at different heights. The difference in height enables an owlit to determine if a noise is coming from a high distance or from the ground. Another interesting feature of many owls is a flat heart-shaped face. The shape of its face functions as a reflector that makes faint sounds louder. These two features enable owls to be the great hunters they are and helps them to hunt in the dark.

Not all animals and insects have “ears”; some have holes in either in their head or in another part of their body, and others have eardrums, such as birds, insects, and fish. Fish’s ears, for example, are located under its skin behind its eyes. This way, a fish can pick up on vibrations that pass their skin under the water. Other fish makes some of these noises by vibrating an internal organ or by rubbing their fins together. Fish use these vibrations to communicate with other fish, to mate, to warn other fish, or to swim together in groups.

Smell: Animals with different smelling needs have been created with different noses and different smelling abilities. Among the different abilities and noses, an elephant’s nose stands out in many individuals’ minds; at least mine. These animals’ noses are so amazingly equipped with different functions, it is surprising. An elephant’s nose (trunk) and upper lip weighs, on average, 300 lbs. (136 kgs.), and can take up and hold more than one gallon (3.7 lt.) of water at a time for spraying on another animal’s back. The trunk is also strong enough to pick up large logs, yet functional enough to gather thin blades to eat. In addition, an elephant can raise its trunk high in the air to smell if any predators are in the area. Another function that I grin at, is that elephants weighing so heavy sink to the bottom of a rivers when they try crossing it; however, they use their noses as snorkels when crossing a deep river by lifting their noses high above the water line to breathe.

Dogs have an astounding sense of smell; they are one of the animals with the best sense of smell. Dogs can pick up odors in concentrations of one part per trillion. A book called Scent, published by veterinarian Dr. Hugo Verbruggen, and dog trainer Milo D. Pearsall, mentions an experiment that illustrates how well dogs can pick up odors. It mentions that if a single gram of butyric acid, a chemical constituent in human perspiration, were released in a ten-story building and evaporated, a human being might be able to smell the odor for a very short moment by sniffing at a window. A dog, in comparison though, would be able to pick up the odor in the same amount if it were to spread over a city the size of Philadelphia anywhere within the city up to an altitude of three hundred feet (90 meters).4 It also mentions that if humans had only ten percent of a dog’s smelling ability that dogs have, we would have a totally different understanding of our world we.

Camels are desert animals that have been created with special channels that can hold moisture in the dry desert. Also, when the wind blows, a camel can close its nostrils to keep out the sand and dust.

Ants also fascinate me. These tiny creatures use odors to identify if an ant belongs in their colony or if it is an intruder. In addition, when an ant dies a certain odor is released, and other ants in the colony will carry the dead ant to a burial site. An experiment has been performed by scientists that placed this “dead” odor on a healthy ant. Although the marked ant was struggling and kept returning to the nest, other ants constantly carried this marked ant to their burial grounds in the belief that it was dead.5

Taste: Taste and smell are chemical senses. Although scientists can only guess what an animal can and does taste, they do know that animals have different taste buds. Taste buds are made up of tiny taste cells that enable us to taste sweet, sour, bitter, and salty substances. Mammals have the most taste buds, while birds have the fewest; insects have none. However, these animals and insects have special taste cells to detect the certain foods they need for survival.

Touch: All animals have a sense of touch. Many scientists believe that touch is the most important sense. The sense of touch indicates if we are hurt, cold, hot, and much more. Blind and visually impaired individuals rely on the feeling of touch to read Braille. Many animals and insects, however, have built-in antennas that help them avoid too close physical contact with other insects and help them detect food and surrounding conditions.

A blowfly (any fly that deposits its eggs on meat or wounds), for instance, uses its antennas to determine if the wind conditions are best for flying. If the wind is blowing too fast, the blowfly will wait until the wind calms down. This is an important feature, for this insect would not be able to survive flying in a strong wind.

Many animals and insects rely on the sensing of vibrations. For example, a spider relies on the shaking of its web to understand if it has caught food or if another spider has come to mate. A spider feels the vibrations through its long legs by waiting at the edge of its web. It is understood that when a spider returns to its web, it shakes the web to see how it vibrates. The results will let it know if something has been caught.

It is also interesting that some animals seek and show affection through touch, just like human beings do. Cats, dogs, monkeys, seals, and lions are some examples that show love and affection. As a cat owner, it is interesting to see the understanding of affection through touch. They enjoy being petted and seek for affection. A question asked by people, who have a cat or have been near a cat, is that why do cats purr and what causes this noise. Scientists believe that purring is produced by blood in a large vein in the chest that vibrates and is then magnified by air in the windpipe.6 Someone petting a cat can actually feel this vibration. Cats usually purr when they are happy or when being shown affection. However, the cat’s purr is more than a sign of content. Kittens, unlike many animals, are born blind and deaf. The vibration of their mother’s purring is a physical sign that the kittens can feel; it is somewhat of a signal to the kittens to be close to the mother and nurse. Also, the kittens’ purr is a signal back to the mother that their kittens are getting their milk and are healthy. This is an extraordinary survival mechanism.

“Super-natural senses”: There are several sensing abilities that scientists can not explain or categorize due to the several unique senses possessed by several animals and insects. Among them is the mosquito’s remarkable sense of heat that leads them to their victims. Female mosquitoes follow have several, however, the most remarkable one is that they can sense temperature differences of less than 1/250th of a degree Fahrenheit. This amazing sense of temperature enables them to land on the warmest and best vein of blood for food.

Another sense scientists have difficulty explaining is that birds, bees, and some other creatures have magnetism. Just as a compass has a magnetic needle that points north, these creatures have natural magnets that help them migrate and find food by using the earth’s magnetic field. They have natural tiny crystals of iron oxide, or also called magnetite, made front iron found in their blood. This enables these adorable creations to still find their way even when they can not see the sun.

People for many years have been puzzled how animals can sense an earthquake before its any “obvious” signs. One of the explanations is that animals, as described throughout the article, have unique and even, in some cases, better senses than human beings. Therefore, they are able to pick up on vibrations, sounds, and odors that humans physically can not, which may indicate to them that a disaster is about to occur.

A final note: Besides their senses, animals have a uniqueness and wondrous superiority over other animals the other with their physical attributes and characteristics. For example, some animals see or hear better than other animals, and some animals have unique physical attributes that other animals do not have. If you look at the beautiful and majestic kingdom of animals, you will find that each animal has a different beauty and awe that deserves much appreciation. This is a component that makes this world a fascinating and perfectly created one.

REFERENCES

1. The National Wildlife Federation “What do Do Animals See, Hear, Smell, and Feel?” (1990).
2. Ibid
3. Ibid
4. Roger A Caras, A Dog is Listening. Summit Books. 1992.
5. The National Wildlife Federation” What do Do Animals See, Hear, Smell, and Feel?” (1990).
6. Arline Bleecker, “Why Do Cats Sulk?” Globe Digests. 1998.