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Classic rough analmal training

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wwe diva jillian hall desnuda. cual es el significado de aficionado. fotos de cerca chicas desnudas. la chica desnuda más caliente del mundo. gratis amature uk wives películas porno. videoclips de chica desnuda gratis. fiesta de cumpleaños del castillo del balneario. Author contributions: Legged animals routinely negotiate rough, unpredictable terrain with agility and stability that outmatches any human-built machine. Yet, we know surprisingly little about how animals accomplish this. Current knowledge Classic rough analmal training largely limited to studies of steady movement. These studies have revealed fundamental mechanisms used by terrestrial animals for steady locomotion. However, it is unclear whether these models provide an appropriate framework for the neuromuscular and mechanical strategies used to achieve dynamic stability over rough terrain. Perturbation experiments shed light on this issue, revealing the interplay between mechanics and neuromuscular control. We measured limb mechanics of helmeted guinea fowl Numida meleagris running over an unexpected drop in terrain, comparing their response to predictions of the mass—spring running click at this page. Surprisingly, although limb stiffness varies dramatically, it does not influence the response. This result agrees with a mass—spring model, although it differs from previous findings on humans running over surfaces of varying compliance. However, guinea fowl sometimes deviate from mass—spring dynamics through posture-dependent work performance of the limb, leading to substantial energy absorption following the perturbation. This posture-dependent actuation allows the animal to absorb energy and maintain desired velocity on a sudden substrate drop. Thus, posture-dependent work performance of the limb provides inherent velocity control Classic rough analmal training rough terrain. These findings highlight how Classic rough analmal training mechanical models extend to unsteady conditions, providing fundamental insights into neuromuscular control of movement and the design of dynamically stable legged robots and Classic rough analmal training devices. All legged terrestrial animals use similar basic mechanisms for steady locomotion 1 — 7. Mallus acteres nude pics Pictures created by keys on your keyboard.

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Euro blonde teen creampie classic ebony lesbia. This is not soppy wishful thinking but the result of studying "co-evolution, the two species evolving towards each other". We forget that the play between species, enjoyed by dogs and humans, is very rare.

The family feeling that wolves display has been replaced in dogs by "an intense need to bond with people". Bradshaw says that from the moment puppies open their eyes, they start Classic rough analmal training bond with people "completely, spontaneously and as hard as they can". He writes about love science plays safe and calls it "attachment" but in answer to the question: The closest Bradshaw comes to being interventionist is on this subject he Classic rough analmal training excellent, easy instructions on how to train a dog not to feel separation anxiety.

Read more is determined to make "It's a dog's life" into a positive statement. We talk about the future — and his sense that there is an urgent need to reform pedigree breeding if dogs are to have a healthy future. We talk about the past — and the dogs from his own life: We talk, too, Classic rough analmal training how good dogs are at reading our body language Classic rough analmal training and he makes one determined to read theirs correctly he is a close student of every twitch of ear and tail.

I ask about his title: Before he leaves, Bradshaw and I have a tug of war with Lily in which you have to be a dog owner to understand how cutting-edge this is she is repeatedly allowed to win. She trashes a toy duck and shreds a rope. It is a great and victorious afternoon this web page as far as she is concerned.

Here's Bradshaw on tug-of-war research: Topics Animal behaviour The Observer. Reuse this content. Order by newest oldest recommendations. Show 25 25 50 All. The hypothesized mass—spring model is a passive, energy-conservative system that consists of a point mass attached to a mass-less, linear compression spring 34. This model differs from some recent approaches in that i no small angle assumptions are made in the equations of Classic rough analmal training 19 and ii gravity is Classic rough analmal training ignored This approach necessitates a numerical solution but provides a more realistic approximation of guinea fowl behavior.

In the flight phase, the body follows a Classic rough analmal training path. In steps with a drop in terrain, all model Classic rough analmal training were the same as the level running simulation unless specified otherwise.

The leg spring in this model resists loads only in compression along its long axis it does not resist torque, shear, or axial tension. At high speeds the gravitational term is small, and limb loading is limited by the momentum of the body directed along the leg Classic rough analmal training axis.

For consistency with measured mass-specific limb work values, we normalize for size by canceling the mass m term. The total energy stored in the leg spring during loading is equal to the peak force times its change in length compression. Energy is stored negative work until peak force and returned positive work as force declines, resulting in absolute limb work equal to twice the energy stored.

All mechanical variables were made dimensionless for statistical analysis by normalizing to body mass mthe acceleration of gravity gand L t 4. We used simple linear regression to compare measured absolute limb work to that predicted for a Classic rough analmal training system.

To account for multiple simultaneous tests, we adjusted the significance level for each test by using the sequential Bonferroni technique. Although the mass—spring model exhibits nonlinearities in many variables, many of the relationships are approximately linear over a biologically relevant range 3. For example, simulation of the mass—spring model over the range of experimentally measured limb contact angles reveals a nonlinear relationship between the limb contact angle and the ground reaction impulse.

Nonetheless, the relationship can be approximated with an inverse linear equation, resulting in an R 2 of 0. The authors declare no conflict of interest. This article is a PNAS direct submission. Published online Oct Monica A. Andrew A. Edited by George N. Received Feb This article has been cited by other articles in PMC. Abstract Legged animals routinely negotiate rough, unpredictable terrain with agility and stability that outmatches any human-built machine.

Open in a separate window. Results During the time between false floor and ground contact, the limb continues retracting until the foot contacts the lower substrate Fig. Table 1. Ground Reaction Impulse. Limb Mechanics. Mass—Spring Model. Statistical Analysis. Footnotes The authors declare no conflict of interest.

Sexy senes Watch Alison brie gillian jacobs gq Video Sexy dateing. But I had been hoping he might have a solution to what happens when the sense of smell gets out of hand: Lily, whenever there is a roast in the oven, is overcome with greed and longing — and barks. On this matter, he says only: For anyone interested in dog emotion, In Defence of Dogs is also a sentimental — and surprising — education. The first shocker is this: So the look Lily gives us when discovered illegally on the sofa creeping off, flashing the whites of her eyes is not guilt? Bradshaw explains she may know to associate that basking on the sofa leads to owner disapproval but that is not the same as feeling guilt, or as having the mental equipment to differentiate between right and wrong. Less surprising is Bradshaw's sense that dogs may be capable of jealousy when I give my husband a hug, Lily wants to be part of the action. But dog jealousy is not of the all-consuming, Othello sort: Bradshaw's most incredible — and gratifying — assertion is that dogs are more interested in people than in other dogs. This is not soppy wishful thinking but the result of studying "co-evolution, the two species evolving towards each other". We forget that the play between species, enjoyed by dogs and humans, is very rare. The family feeling that wolves display has been replaced in dogs by "an intense need to bond with people". Bradshaw says that from the moment puppies open their eyes, they start to bond with people "completely, spontaneously and as hard as they can". He writes about love science plays safe and calls it "attachment" but in answer to the question: The closest Bradshaw comes to being interventionist is on this subject he quotes excellent, easy instructions on how to train a dog not to feel separation anxiety. Bradshaw is determined to make "It's a dog's life" into a positive statement. We talk about the future — and his sense that there is an urgent need to reform pedigree breeding if dogs are to have a healthy future. We talk about the past — and the dogs from his own life: Thus, posture-dependent work performance of the limb provides inherent velocity control over rough terrain. These findings highlight how simple mechanical models extend to unsteady conditions, providing fundamental insights into neuromuscular control of movement and the design of dynamically stable legged robots and prosthetic devices. All legged terrestrial animals use similar basic mechanisms for steady locomotion 1 — 7. In the stance phase of bouncing gaits, such as hopping and running, kinetic energy KE and gravitational potential energy of the body cycle in phase, decreasing during the first half of stance and increasing during the second half 1. Elastic recoil allows this energy to be stored and returned by the elastic structures of the limb 8 — Consequently, a simple mass—spring model is often used to describe the stance phase dynamics of these gaits. The model consists of a point mass and a linear compression spring 2 — 4. Despite the simplicity of this model, it appears that humans and animals maintain mass—spring dynamics over a broad range of locomotor conditions by adjusting model parameters: Nonetheless, the mass—spring model is a conservative system, meaning that the total mechanical energy of the body E com does not change over a stride. If energy must be absorbed or produced to change E com in acceleration or deceleration, for example , the animal must deviate from the simplest spring-like mechanics. Thus, although this model describes well the body mechanics of steady running, it is not yet clear whether it applies to animals running in more complex conditions, including rough or unpredictable terrain. We test the hypothesis that helmeted guinea fowl Numida meleagris use conservative mass—spring limb mechanics to maintain running stability following this perturbation. In response, the animal can i rapidly adjust limb position and stiffness to prevent changes in mechanical energy, ii redistribute energy between gravitational potential energy and KE, or iii actuate the limb to dissipate energy and change E com for example, to maintain the same velocity at a lower body height The animal can accomplish the first two options through conservative spring-like limb mechanics. Limb dynamics following an unexpected perturbation. A Still frame just prior to an unexpected drop in substrate height. The bird has placed its foot for ground contact on tissue paper that camouflages an 8. B Limb angle and limb length over the course of a step beginning from midswing phase prior comparing level running gray traces; C with perturbed running black traces; U. Dashed gray line indicates the time of beginning of stance for C trial and tissue paper contact for U trial ; dashed black line indicates beginning of stance for U trial. The trial shown here followed the KE h mode response pattern observed in ref. This experimental perturbation approach can help reveal the interplay between mechanics and neuromuscular control of running. Similar perturbation approaches have elucidated control strategies for walking, postural stability, lateral stability in hexapedal running, and visuomotor control of flight e. During the time between false floor and ground contact, the limb continues retracting until the foot contacts the lower substrate Fig. Limb loading and work following the perturbation are consistent with the mass—spring model. If the virtual leg at contact is perpendicular V o , J is zero. On average, the ground reaction forces measured during the stance phase following the perturbation are approximated well by a conservative mass—spring model Fig. The magnitude and time-course of ground reaction forces predicted for steady running through numerical simulations using Eqs. However, adjustment of model k leg does not yield an improved match between model and experimental ground forces Fig. Comparison of ground forces between model and experiment. A Ground forces measured during the stance phase of level running and following a drop in terrain B Schematic of the hypothesized mass—spring model Eqs. Modeled forces were obtained through numerical integration of Eqs. Limb stiffness does not significantly correlate with any of the measured stance-phase mechanical variables Table 1. Dependent variables: The value in each cell is the fraction of variance explained by each X variable. The last entry in each column is the R 2 for the full model. The limb as a whole largely preserves spring-like loading characteristics in the step following a terrain drop Fig. Because the linear compression spring in the model is passive and energy-conservative, and resists only axial compression, limb loading is limited by the momentum of the body directed along the leg spring axis during stance Eq. Energy storage in the leg spring is limited by the axial kinetic energy at the instant of ground contact. Nonetheless, even during level running, the spring-like dynamics of the limb as a whole arise largely through a balance of positive and negative work among the individual joints, rather than through spring-like patterns of energy storage and return at every joint Fig. Furthermore, when limb length at the instant of ground contact L o differs from level running, the limb produces or absorbs net energy through a shift of the balance of work among the joints. Thus, altered limb posture at ground contact is associated with a shift in the balance of work among the joints of the limb, leading to substantial energy production or absorption in the perturbed step. Joint and limb work during stance. A — D Hip, knee, ankle, and tarsometatarsophalangeal work over the course of stance, showing a typical level running trial solid gray and the two perturbation response modes observed in all individuals: KE h mode dotted red and E com mode dashed blue In KE h mode, the body accelerates forward, whereas in E com mode it does not. E Total limb work over the course of stance. Trending Searches. All Categories. Big Ass. Big Dick. Big Tits. Double Penetration. Female Orgasm. Solo Male. Step Fantasy. Verified Amateurs. Virtual Reality. Young and Old. HD Results only. Ads are the worst, right? Join RedTube Premium and never look back. Adblock users get a week free. Cam Sex Porn Games Premium. Related Videos. Classic rough Analmal Training Flag this video. Add to Favorites. This is the same type of chair used for all training approaches leash, pole and automated. The top of the primary box had a fixed front neck plate and a removable back neck plate. The back of the chair had a guillotine-style door, and the floor of the chair was an aluminium perch that permitted the animal to achieve solid footing while letting waste pass onto a bottom tray. The top of the chair had a removable clear cover that could be snapped into place using metal pins, to prevent escape before the neck plate was inserted. The chairs were built on-site. The chairs were attached securely to the housing cage using 1-inch-wide nylon webbing straps with feed-through buckles McMaster-Carr. We cut 4—5 holes in the chair to permit attachment of our touch sensor bar, the motion-sensor, and ultrasonic range sensors. These devices were framed by acrylic plates that could be screwed into the chair or attached with heavy-duty Velcro. Chair and Arduino workstation setup. The chair was attached to the home cage using two nylon-web straps. The guillotine door is shown in the secured open position. We attached a plastic frame between the cage and chair, to provide a passageway for the monkey while still permitting the back door to be closed. Arduino workstation. Made of T-slotted framing, the wheeled station comprised a wireless IP camera 1 , a reward-circuit and water bottle holder 2 , and a boxed platform to hold the Arduino and laptop. Major components of the electronic circuit. These frames were designed to hold a 1-L water bottle on top, to allow gravity dispensation of the liquid, and a small plate for a solenoid activation circuit triggered by the Arduino. The ultrasonic range sensors returned a voltage step with a duration proportional to the proximity of the animal. The reward circuit used a V power source to activate a two-way solenoid valve www. The sensors and Arduino were connected on 1. Code and schematics are available at https: We used Matlab to record the reward delivery times as marked by the Arduino microcontroller and the proximity sensor readings. The Arduino was programmed using slightly modified example scripts such as https: The program opened serial communication once, and then entered an infinite while-loop to scan the serial port every few milliseconds. We only collected this fine temporal precision data on monkey G. The animals were scheduled to receive all their water during training, and the minimum duration of the session was determined by how long the animal took to get its water, up to six hours per day. The training regimen included three stages: The animals were first trained to touch a short, metal bar connected to the capacitive touch sensor 2. The touch bar was fixed onto a non-conductive acrylic plate that could be attached to the bars of the cage. If the animals touched the bar, they were rewarded with a ms-long pulse of water. After they learned to touch the bar, we fixed the touch bar inside the front plate of the chair. The chair was then attached to the home cage and water was released via the chair lixit. This required the animal to reach into the chair to touch the bar. We programmed the Arduino to dispense larger rewards upon bar touch when the monkey was closer to the distance sensors. We defined three zones within the chair: The Arduino was programmed to deliver higher rewards in the closer zones: Upon improvement, we reduced the reward magnitude scale to 50 ms, ms and ms. This training lasted until the animal sat entirely within the chair while being rewarded for bar touch, and did not return to the cage if the experimenter walked into the room. This encouraged work and prevented extinction. Once the animals learned to put their legs and bottom inside the chair, we familiarized them to the chair door closing behind them. We started this training using two alternative strategies, gradual desensitization or flooding. In gradual desensitization, we lowered the door one inch at a time and offered clicks and rewards if the animal stayed in place water, grape and apple pieces. The animal was always free to duck under the door and return to his home cage, and rewarding resumed upon return to the chair. In the flooding approach, the door was quickly lowered into place after the animal entered the chair, followed by abundant rewards. Our approach to neckplate insertion took place in the laboratory and consisted of two steps: We then let the monkey sit with the Arduino touch bar reward system active, while in the lab, while we worked on other tasks..

References 1. Am J of Physiol. McMahon TA.

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J Exp Biol. Blickhan R. J Biomech. Biomechanics and Neural Control of Posture and Movement. New York: Springer; J Neurophysiol.

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Kimber Woods 23 videos. Tinna Angel 8 videos. Gia Derza 17 videos. The chair was attached to the home cage using two nylon-web straps. The guillotine Classic rough analmal training is shown in the secured open position. We attached a plastic frame between the cage and chair, to provide a passageway for the monkey while still permitting the back door to be closed.

Arduino workstation. Made of T-slotted framing, the wheeled station comprised a wireless IP camera 1Classic rough analmal training reward-circuit and water bottle holder 2and a boxed platform to hold the Arduino and laptop. Major components of the electronic circuit. These frames were designed to hold a 1-L water bottle on top, to allow gravity dispensation of the liquid, and a small plate for a solenoid activation circuit triggered by the Arduino.

The ultrasonic range sensors returned a voltage step with a duration proportional to the proximity of the animal. Classic rough analmal training reward circuit used a V Classic rough analmal training source to activate a two-way solenoid valve www. The sensors and Arduino were connected on 1. Code and schematics are available at https: We used Matlab to record the reward delivery times as marked by the Arduino microcontroller and the proximity sensor readings.

The Arduino was programmed using slightly modified example scripts such as https: The program opened serial communication once, and then entered an infinite while-loop to scan the serial port every few milliseconds. We only collected this fine temporal precision data on monkey G. The animals were scheduled to receive all https://images.e-paper.work/web-4149.php water during training, and the minimum duration of the session was determined by how long the animal took to get its water, up to six hours per day.

The training regimen included three stages: The animals were first trained to touch a short, metal bar connected to the capacitive touch sensor 2. The touch bar was fixed onto a non-conductive acrylic plate that could be attached to the bars of the Classic rough analmal training.

If the animals touched the bar, they were rewarded with a ms-long pulse of water. After they learned to touch the bar, we fixed the touch bar inside the front plate of the chair. The chair was then attached to the home cage go here water was released via the chair lixit. This Classic rough analmal training the animal to reach into the chair Classic rough analmal training touch the bar.

We programmed the Arduino to dispense larger rewards upon bar touch when the monkey was closer to the distance Classic rough analmal training. We defined three zones within the chair: The Arduino was programmed to deliver higher rewards more info the closer zones: Upon improvement, we reduced the reward magnitude scale to 50 ms, ms and ms.

This training lasted until the animal sat entirely within the chair while being rewarded for bar touch, and did not return to the cage if the experimenter walked into the room. This encouraged work and prevented extinction.

Once the animals learned to put their legs and bottom inside the chair, we familiarized them to the chair Classic rough analmal training closing behind them. We started this training using two alternative strategies, gradual desensitization or flooding. In gradual desensitization, we lowered the door one inch at a time and offered clicks and rewards if the animal stayed in place water, grape and apple pieces.

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The animal was always free to duck under the door and return to click home cage, and rewarding Classic rough analmal training upon return to the chair.

In the flooding approach, the door was quickly lowered into place after the animal entered the chair, followed by abundant rewards. Our approach to neckplate insertion took place in the laboratory and consisted of two steps: We then let the monkey sit with the Arduino touch bar reward system active, while in the lab, while we worked on other tasks. Second, we got him used to the neck plate by successive approximation: Finally, we Classic rough analmal training sliding the neckplate in small intervals with rewards at each step.

Once the monkey let the neckplate make contact with his fur, we could try one of two approaches: Desensitization meant that we kept going with the small step approach until the neckplate could prevent crouching.

Flooding meant that we slid the neckplate quickly enough to prevent the animal from crouching. Because monkey R had self-injurious behaviors, we only used sensitization in this case.

We Classic rough analmal training with flooding with monkey G to determine whether this would accelerate the process it did not, see Results.

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Finally, we calculated a rough approximation Classic rough analmal training the number of person-hours spent actively working with the monkeys every session above, based on our daily notes, but these should be seen as approximate. Monkey R and monkey G learned to sit inside their chairs, and tolerate closing the door and inserting the neck plate, within 21 and 14 days.

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Bbw having a shower. Neuroscience research on non-human primates usually requires the animals to sit in a chair. To do this, typically monkeys are fitted with collars and trained to enter the chairs using either a pole, leash and jump cage. Animals may initially show resistance and risk injury. We have developed an automated chair-training method that minimizes restraints to ease the animals into their chairs.

We developed a method to automatically train animals to enter a primate chair and stick out their heads for neckplate placement. To do this, we fitted the chairs with Arduino microcontrollers coupled to a water-reward system and touch- and proximity sensors. Classic rough analmal training found that the animals responded well to the chair, partially entering the chair within hours, sitting inside the chair within Classic rough analmal training and allowing us to manually introduce a door Classic rough analmal training neck plate, all within 14—21 sessions.

Although each session could last many hours, automation meant that actual training person-hours could be as little as half an hour per day.

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The biggest advantage was that animals showed little resistance to entering the chair, compared to monkeys trained by leash pulling. This automated chair-training method can take longer than the standard collar-and-leash approach, but multiple macaques can be trained in parallel with fewer person-hours. It is also a promising method for animal-use refinement and in our case, it was the only effective training approach for an animal suffering from a behavioral pathology.

Non-human primates are the best animal model for studying the neural mechanisms of high-level and cognitive behaviors because their Classic rough analmal training are so similar to our own. However, this similarity brings its own complications: Monkeys show a wide range of temperaments and may develop Classic rough analmal training and self-injurious behaviors in response to experimental requirements Novak Classic rough analmal training al.

One example of a necessary but counterintuitive task is chair training: Historically, chair training required using a pole or a leash to transfer Classic rough analmal training primate into the chair. Once in the chair, the animal is given abundant liquid and fruit rewards.

After some time, the great majority of animals acclimatize to the chair and enter it willingly. Over time, the chair-training method has been improved in two significant ways: Our project advances the latter approach, by using a box-chair design while substituting person-hours with an automated reward system. Our initial motivation was to train an animal with self-biting, stress-coping behaviors using a gentler approach, while https://mom.e-paper.work/video-27-04-2020.php keeping an efficient workflow.

Arduinos are cheap and flexible microcontroller boards, programmed using simple open-source Classic rough analmal training, which can be interfaced with different types of sensors and motors. This system obviated collars, and the number of automated training sessions required to get the monkey in the chair, with a neckplate on, was not much higher than the number of sessions required by all-human training. Our goals were to reduce the number of person-hours required during initial training and to provide an alternative to monkeys with behavioral problems.

This article conforms to the Animal Research: Both animals were adult male rhesus macaques Macaca mulattamonkey R 8 year-old, 13 kg and monkey G 4 year-old, 5 kg. Water and fruits were available during experimental sessions. Monkey R arrived with a history of abnormal and self-injurious behaviors, including hair-pulling and arm-biting.

Both animals were acclimatized for two weeks. Monkey R was collared with a rubber-lined chain and a Classic rough analmal training extension with an O-loop at the end for Classic rough analmal training leash. Monkey R began under our standard training, which is as follows: Animals are acclimatized to the squeeze by confining them to the front for several minutes.

After they learn to sit calmly while being confined, we get them used to being touched with the small hook by putting it close to their collar loop. Usually, animals resist to being touched with the hook, batting it away or showing fear grimaces. However, they gradually show less resistance as this action is click the following article by fruit and liquid rewards.

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However, before graduating to leash training, monkey R Classic rough analmal training his self-injurious behavior, biting himself at the sight of Classic rough analmal training hook, and we transferred him to the new training protocol. Monkey G was never collared or leash-trained, only clicker-trained. This is the same type of chair used for all training approaches leash, pole and automated. The top of the primary box had a fixed front neck plate and a removable back neck plate.

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The back of the chair had a guillotine-style door, and the Classic rough analmal training of the chair was an aluminium perch that permitted the animal to achieve solid footing while letting waste pass onto a bottom tray. The top of the chair had a removable clear cover that could be snapped into place using metal pins, to prevent escape before the neck plate was inserted.

The chairs were built on-site.

The chairs were attached securely to the housing cage using 1-inch-wide nylon webbing straps with feed-through buckles McMaster-Carr. We cut 4—5 holes in the chair to permit attachment of our touch sensor bar, the motion-sensor, and ultrasonic range sensors. These devices were framed by acrylic plates that could be screwed into the chair or attached with heavy-duty Velcro.

Chair and Arduino workstation setup. The chair was attached to the home cage using two nylon-web straps. The guillotine door is Classic rough analmal training in the secured open position.

We attached a plastic frame between the cage and chair, to provide a passageway for the monkey while still permitting the back door to be closed.

Arduino workstation. Classic rough analmal training of T-slotted framing, the wheeled station comprised a wireless IP camera 1a reward-circuit and water bottle holder 2and a boxed platform to hold the Arduino and laptop. Major components of the electronic circuit. These frames were designed to hold a 1-L water bottle on top, to allow gravity dispensation of the liquid, and a small plate for a solenoid activation circuit triggered by the Arduino.

The ultrasonic range sensors returned a voltage step with a duration proportional to the proximity of the animal. The reward circuit used a V power source to activate a two-way solenoid valve www. The sensors and Arduino were connected on 1. Code and schematics are available at https: We used Matlab to record the reward delivery times as marked by the Arduino microcontroller and the Classic rough analmal training sensor readings. The Arduino was programmed using slightly modified example scripts Classic rough analmal training as https: The program opened serial communication once, and then entered an infinite while-loop to scan the serial port every few milliseconds.

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We only collected this fine temporal precision data on monkey G. The Classic rough analmal training were scheduled to receive all their water during training, and the minimum duration of the session was determined by how long the animal took to get its water, up to six hours per day. The training regimen included three stages: The animals were first trained to touch a short, metal bar connected Classic rough analmal training the capacitive touch sensor 2.

The touch https://desk.e-paper.work/index-2019-12-26.php was fixed onto a non-conductive acrylic plate that could be attached to the bars of the cage. If the animals touched the bar, they were rewarded with a ms-long pulse of water. After they learned to touch the bar, we fixed the touch bar inside the front plate of the chair. The chair was then attached to the home cage and water was released via the chair lixit.

This required the animal to reach into the chair to touch the bar. We programmed the Arduino to dispense larger rewards upon bar touch Classic rough analmal training the monkey was closer to the distance sensors.

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We defined three zones within the chair: The Arduino was programmed to deliver higher rewards in the closer zones: Upon improvement, we reduced the reward magnitude scale to 50 ms, ms and ms. This training lasted until the animal sat entirely within Classic rough analmal training chair while being rewarded for bar touch, and did not return to the cage if the experimenter walked into the room. This encouraged work and prevented extinction. Once the animals learned to put their Classic rough analmal training and bottom inside the chair, we familiarized them to the chair door closing behind them.

We started this training using two alternative strategies, gradual desensitization or flooding. In gradual desensitization, we lowered the door one inch at a time and offered clicks and rewards if the animal stayed in place water, grape and apple pieces. The animal was always free to duck under the door and return to his home cage, and rewarding resumed upon return to the chair.

In check this out flooding approach, the door was quickly lowered into place after the animal entered the chair, followed by abundant rewards.

Our approach to neckplate insertion took place in the laboratory and consisted of two steps: We then let the monkey sit with the Arduino touch bar reward system Classic rough analmal training, while in the lab, while we worked on other tasks.

Neuroscience research on non-human primates usually requires the animals to sit in a chair.

Second, we got him used to the neck plate by successive approximation: Finally, we began sliding the neckplate in small intervals with rewards at each step. Once the monkey let the neckplate make contact with his fur, we could try one of two Classic rough analmal training Desensitization meant that we kept going with the small step approach until the neckplate could prevent crouching.

Flooding meant that we slid the neckplate quickly enough to prevent the animal from crouching. Because monkey R had self-injurious Classic rough analmal training, we only used sensitization in this case.

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We experimented with Classic rough analmal training with monkey G to determine whether this would accelerate the process it did not, see Results. Finally, we calculated a rough approximation of the number of person-hours spent Classic rough analmal training working with the monkeys every session above, based on our daily notes, but these should be seen as approximate.

Monkey R and monkey G learned to sit inside their chairs, and tolerate closing the door and inserting the neck plate, within 21 and 14 days.

Sex Vesuwal Watch Amateur blow job compilation porn Video Sexy wimin. Bradshaw believes our relationship with dogs has been sadly distorted. He writes: It is what we are all aiming for — to keep control of our own lives. It is a fundamental biological urge. But Bradshaw is far from suggesting we slacken in our efforts to train our dogs it is the more brutal training methods he would like to banish. But I wonder how Cesar Millan and his followers will respond to these findings. Millan, America's internationally influential "dog whisperer" has made a television career explaining dog psychology in terms of wolf lore. Bradshaw says: He is now embracing reward-based methods. All that stuff he spouted about wolves was not based on science. Bradshaw favours humane, reward-based training. The latest science shows that dogs learn to "please their owners". It is wonderful to hear this: Bradshaw first went to the dogs — in the best sense — because of his interest in "the science of smell. I used to study ants, wasps, moths… then I thought: Now canine science is a "huge industry — with people working worldwide". The reasons for this include the sequencing of the canine genome, the rise in animal welfare science, increased interest from vets wanting to specialise in dog behaviour and primatologists who can no longer afford to study chimpanzees. Dogs are now used not only for narcotics but to help epileptics able to alert them when they are on the edge of a seizure and to sniff out everything from bedbugs to shark's fins and even certain kinds of cancer. Bradshaw, in his book, follows the dog's nose brilliantly it was intriguing to learn that while dogs love to sniff other dogs they "do not much like being sniffed themselves". The animals maintained their weights during training. Both animals learned to touch the bar in their cage within three hours. The animals were allowed to continue in-cage touch training for up to three sessions monkey R, 9 hours in two sessions; monkey G, 5. We then attached the chair to the cage, with the door open, and moved the touch bar to the front of the chair. Monkey R was our first subject, and we let him reach into the chair without a proximity sensor; he did so for 12 h 2 sessions without much inclination to get into the chair. Next we attached a single proximity sensor to give increasing reward sizes as the animal sat closer to the front of the chair when touching the bar. Finally we attached two proximity sensors, and then the animal was persuaded to sit calmly inside the chair to drink water. This occurred within 7 hours two sessions. Consequently, we introduced the two-sensor system immediately with monkey G, and this animal learned to bar touch while sitting entirely inside the chair in two sessions 7 h total. The time to entry and amount of time spent in the chair improved throughout subsequent sessions Fig. Monkey R developed a habit of leaving at least one leg out of the chair. To complete his training, we used the cage squeeze mechanism to nudge his leg into the chair; shortly thereafter he learned to move into the chair completely. Training activities per daily session. Each histogram shows the duration of the session height and the type of training procedures used that day colors. Estimated person-time hours per session. Occurences of bar touches by monkey G over five sessions, after proximity sensors were introduced into the chair. Each color represents the same session as in B. Once the animals sat in the chair for minutes at a time, we trained them to allow us to close the back door and the neckplate. With monkey R, we used gradual desensitization, lowering the door slowly and rewarding after each movement if the animal stayed still. This took a collective time of 7 hours of training, 5. By the end of training, monkey R was comfortable in the chair with the trainer present, showed little resistance to the closing of the door. This gradual desensitization approach was important for this monkey because of his behavioral pathology history and relatively large size; moving out of the chair was possible but energetically costly. This was in contrast with monkey G, a younger, smaller, less patient animal. Because this animal did not have any behavioral pathologies, we tried using flooding to see if we could finish neckplate training faster and with fewer person hours, lowering the door briskly and confining the animal to the chair for short periods. Once inside, we offered abundant rewards. This approach was less optimal: Although it did require a smaller ratio of person-hours to total hours, the person-hours were only marginally decreased while the total hours were substantially increased. Additionally, monkey G became reluctant to approach the chair and continued proximity sensor training concurrently. Eventually, the monkey became desensitized, showing little reluctance to door closing. We performed training for neckplate insertion in the laboratory instead of the animal housing room. Within each session, the animals were permitted to take breaks playing with the Arduino touch bar circuit while we worked at the computer. For neckplate insertion, we also compared gradual desensitization vs. Using desensitization monkey R , we needed 10 person-hours out of 12 total hours five sessions. Thus we switched to a more gradual desensitization for an additional three sessions 9 person-hours out of 11 total hours. Thus we emphasize that flooding was a weak training approach in both door-closing and neckplate insertion. We conduct a visual neuroscience research program using rhesus macaques, and occasionally we get animals that show significant behavioral pathologies. These animals present us with a dilemma: In this project, we responded to a behaviorally abnormal animal by introducing a patient and cheap training tutor: Arduino microcontrollers. This saves time and reduces much of the stress associated with chair training: Considering the chair training as a whole, the animals responded better to the automatic trainer than to us. By that description, this process is longer. However, the truth is that even after two weeks of leash-based chairing, most monkeys are hardly willing to enter the chair: In this view, the use of automated training does not prolong the process as much as it preserves the focus on achieving a good foundational behavior early on. Again, while we loved automation and believe the monkeys preferred it too, this is going to be most helpful with self-injurious monkeys and when training more than one animal in parallel. If energy must be absorbed or produced to change E com in acceleration or deceleration, for example , the animal must deviate from the simplest spring-like mechanics. Thus, although this model describes well the body mechanics of steady running, it is not yet clear whether it applies to animals running in more complex conditions, including rough or unpredictable terrain. We test the hypothesis that helmeted guinea fowl Numida meleagris use conservative mass—spring limb mechanics to maintain running stability following this perturbation. In response, the animal can i rapidly adjust limb position and stiffness to prevent changes in mechanical energy, ii redistribute energy between gravitational potential energy and KE, or iii actuate the limb to dissipate energy and change E com for example, to maintain the same velocity at a lower body height The animal can accomplish the first two options through conservative spring-like limb mechanics. Limb dynamics following an unexpected perturbation. A Still frame just prior to an unexpected drop in substrate height. The bird has placed its foot for ground contact on tissue paper that camouflages an 8. B Limb angle and limb length over the course of a step beginning from midswing phase prior comparing level running gray traces; C with perturbed running black traces; U. Dashed gray line indicates the time of beginning of stance for C trial and tissue paper contact for U trial ; dashed black line indicates beginning of stance for U trial. The trial shown here followed the KE h mode response pattern observed in ref. This experimental perturbation approach can help reveal the interplay between mechanics and neuromuscular control of running. Similar perturbation approaches have elucidated control strategies for walking, postural stability, lateral stability in hexapedal running, and visuomotor control of flight e. During the time between false floor and ground contact, the limb continues retracting until the foot contacts the lower substrate Fig. Limb loading and work following the perturbation are consistent with the mass—spring model. If the virtual leg at contact is perpendicular V o , J is zero. On average, the ground reaction forces measured during the stance phase following the perturbation are approximated well by a conservative mass—spring model Fig. The magnitude and time-course of ground reaction forces predicted for steady running through numerical simulations using Eqs. However, adjustment of model k leg does not yield an improved match between model and experimental ground forces Fig. Comparison of ground forces between model and experiment. A Ground forces measured during the stance phase of level running and following a drop in terrain B Schematic of the hypothesized mass—spring model Eqs. Modeled forces were obtained through numerical integration of Eqs. Limb stiffness does not significantly correlate with any of the measured stance-phase mechanical variables Table 1. Dependent variables: The value in each cell is the fraction of variance explained by each X variable. The last entry in each column is the R 2 for the full model. The limb as a whole largely preserves spring-like loading characteristics in the step following a terrain drop Fig. Because the linear compression spring in the model is passive and energy-conservative, and resists only axial compression, limb loading is limited by the momentum of the body directed along the leg spring axis during stance Eq. Energy storage in the leg spring is limited by the axial kinetic energy at the instant of ground contact. Nonetheless, even during level running, the spring-like dynamics of the limb as a whole arise largely through a balance of positive and negative work among the individual joints, rather than through spring-like patterns of energy storage and return at every joint Fig. Furthermore, when limb length at the instant of ground contact L o differs from level running, the limb produces or absorbs net energy through a shift of the balance of work among the joints. Thus, altered limb posture at ground contact is associated with a shift in the balance of work among the joints of the limb, leading to substantial energy production or absorption in the perturbed step. Joint and limb work during stance. A — D Hip, knee, ankle, and tarsometatarsophalangeal work over the course of stance, showing a typical level running trial solid gray and the two perturbation response modes observed in all individuals: KE h mode dotted red and E com mode dashed blue In KE h mode, the body accelerates forward, whereas in E com mode it does not. E Total limb work over the course of stance. In level running, the hip produces energy, and the tarsometatarsophalangeal joint absorbs energy, resulting in spring-like energy performance of the whole limb. In KE h mode, the hip produces energy, and the distal joints act as springs, resulting in net positive limb work. In E com mode, the distal joints absorb more energy than the hip produces, resulting in net negative limb work. The two response modes are associated with different initial limb postures. Posture-dependent limb actuation provides a key stabilizing mechanism. However, net energy performance correlates with L o Table 1. When the limb contacts the ground with a crouched posture, it produces net energy. When the limb contacts the ground with an extended limb posture, it absorbs net energy. Differing limb postures at the instant of ground contact are associated with differing initial knee angle Share This Video. Link copied to clipboard. Start at. Video has been sent! Inappropriate content. Video does not play. Spam or misleading. Fetish , HD , Bondage. Related videos Premium videos Recommended videos. Show More. Russian homemade sex video. Recognize a pornstar in this video? Suggest more pornstars Thanks for submitting! Remove Ads. Related Searches: Gold Show. Spookybunz Party Chat. EmmaLovett AnielaXXXX .

The animals maintained their weights during training. Both animals learned to Classic rough analmal training the bar in their cage within three hours. The animals were allowed to continue in-cage touch training for up to three sessions monkey R, 9 hours in two sessions; monkey G, 5. We then attached the chair to the cage, with the door open, and moved the touch bar to the front of the chair.

Monkey R was our first subject, and we let him reach into the chair without a proximity sensor; he did so for 12 h 2 sessions without much inclination to get into the chair. Next we read article a single proximity sensor to give increasing reward sizes as the animal sat closer to the front of the chair when touching the bar. Finally we attached two proximity sensors, and then the animal was persuaded to sit calmly inside the chair to drink water.

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Youporn tits Watch Lesbian mistress use feet slave Video Gauteng porn. This automated chair-training method can take longer than the standard collar-and-leash approach, but multiple macaques can be trained in parallel with fewer person-hours. It is also a promising method for animal-use refinement and in our case, it was the only effective training approach for an animal suffering from a behavioral pathology. Non-human primates are the best animal model for studying the neural mechanisms of high-level and cognitive behaviors because their brains are so similar to our own. However, this similarity brings its own complications: Monkeys show a wide range of temperaments and may develop pathologic and self-injurious behaviors in response to experimental requirements Novak et al. One example of a necessary but counterintuitive task is chair training: Historically, chair training required using a pole or a leash to transfer the primate into the chair. Once in the chair, the animal is given abundant liquid and fruit rewards. After some time, the great majority of animals acclimatize to the chair and enter it willingly. Over time, the chair-training method has been improved in two significant ways: Our project advances the latter approach, by using a box-chair design while substituting person-hours with an automated reward system. Our initial motivation was to train an animal with self-biting, stress-coping behaviors using a gentler approach, while still keeping an efficient workflow. Arduinos are cheap and flexible microcontroller boards, programmed using simple open-source software, which can be interfaced with different types of sensors and motors. This system obviated collars, and the number of automated training sessions required to get the monkey in the chair, with a neckplate on, was not much higher than the number of sessions required by all-human training. Our goals were to reduce the number of person-hours required during initial training and to provide an alternative to monkeys with behavioral problems. This article conforms to the Animal Research: Both animals were adult male rhesus macaques Macaca mulatta , monkey R 8 year-old, 13 kg and monkey G 4 year-old, 5 kg. Water and fruits were available during experimental sessions. Monkey R arrived with a history of abnormal and self-injurious behaviors, including hair-pulling and arm-biting. Both animals were acclimatized for two weeks. Monkey R was collared with a rubber-lined chain and a five-inch extension with an O-loop at the end for the leash. Monkey R began under our standard training, which is as follows: Animals are acclimatized to the squeeze by confining them to the front for several minutes. After they learn to sit calmly while being confined, we get them used to being touched with the small hook by putting it close to their collar loop. Usually, animals resist to being touched with the hook, batting it away or showing fear grimaces. However, they gradually show less resistance as this action is followed by fruit and liquid rewards. However, before graduating to leash training, monkey R reactivated his self-injurious behavior, biting himself at the sight of the hook, and we transferred him to the new training protocol. Monkey G was never collared or leash-trained, only clicker-trained. This is the same type of chair used for all training approaches leash, pole and automated. The top of the primary box had a fixed front neck plate and a removable back neck plate. The back of the chair had a guillotine-style door, and the floor of the chair was an aluminium perch that permitted the animal to achieve solid footing while letting waste pass onto a bottom tray. The top of the chair had a removable clear cover that could be snapped into place using metal pins, to prevent escape before the neck plate was inserted. The chairs were built on-site. The chairs were attached securely to the housing cage using 1-inch-wide nylon webbing straps with feed-through buckles McMaster-Carr. We cut 4—5 holes in the chair to permit attachment of our touch sensor bar, the motion-sensor, and ultrasonic range sensors. These devices were framed by acrylic plates that could be screwed into the chair or attached with heavy-duty Velcro. Chair and Arduino workstation setup. The chair was attached to the home cage using two nylon-web straps. The guillotine door is shown in the secured open position. We attached a plastic frame between the cage and chair, to provide a passageway for the monkey while still permitting the back door to be closed. Arduino workstation. Made of T-slotted framing, the wheeled station comprised a wireless IP camera 1 , a reward-circuit and water bottle holder 2 , and a boxed platform to hold the Arduino and laptop. Major components of the electronic circuit. These frames were designed to hold a 1-L water bottle on top, to allow gravity dispensation of the liquid, and a small plate for a solenoid activation circuit triggered by the Arduino. The ultrasonic range sensors returned a voltage step with a duration proportional to the proximity of the animal. Many multiarticular muscles act across the knee, including hip and ankle extensors and hip flexors. Consequently, the variation in knee motion likely reflects altered force balance among the proximal and distal limb muscles following the perturbation. Unlike the proximal joints, work performance of the distal joints ankle and tarsometatarsophalangeal depends on limb loading and limb posture. The greater variation in distal limb muscle performance might result from higher proprioceptive feedback gain 31 , 32 , greater sensitivity to intrinsic mechanical factors 30 , or both. An in vivo study of guinea fowl digital flexor suggests that this distal muscle is sensitive to intrinsic mechanical factors such as length, velocity, and strain history Further study is needed to evaluate how intrinsic muscle-tendon properties and proprioceptive reflex feedback interact to allow rapid adjustment of distal muscle work performance. Posture-dependent energy performance of the limb provides an important stabilizing mechanism for running over rough terrain. In association with altered L o relative to control, the limb either absorbs energy, stabilizing the bird at the original velocity, or produces energy, stabilizing the bird at a higher velocity. A mass—spring system can achieve stable running at many different periodic trajectories 33 , 34 , each characterized by a forward velocity and body apex height 21 , In a conservative mass—spring running model, a drop in substrate height results in higher forward velocity upon stabilization because lost gravitational potential energy is redistributed to forward KE. This redistribution alone provides stability, because a mass—spring system is less sensitive to perturbations at higher speeds However, animals must control their velocity in addition to avoiding falls. We previously found that guinea fowl maintain stability but often absorb energy and slow down as they respond to a terrain drop We propose that posture-dependent limb actuation provides a simple mechanism for rapidly switching among running trajectories with different forward velocity, thereby automatically controlling velocity in rough terrain. What is the benefit of maintaining a spring-like bouncing motion even when the animal does not benefit from the efficiency of a truly elastic system? Control of running through a mass—spring template may simplify control by reducing the complexity of the system to a few controllable limb parameters 6. Recent research suggests that motor control may be modular, generating movement through a limited set of muscle synergies in which subgroups of muscles are activated together in a stereotyped pattern 18 , Further, these synergies can correspond to task-level biomechanical functions such as endpoint force or kinematics 18 , Similar muscle synergies may exist for running and control parameters such as limb retraction, limb length, and k leg ; thereby reducing the complex pattern of muscle activation to a few modules. Activation of each muscle subgroup could be adjusted through proprioceptive feedback at the spinal level, reducing the need for higher-level control and improving response time. Consequently, although the limb does not achieve truly elastic performance, operation through a mass—spring control template, which might be encoded at the spinal level, could improve stability and simplify the neuromuscular control of running. The data presented here were collected during the same experiments described in a previous study of body COM mechanics Five adult guinea fowl N. In control trials C , the bird ran across a level runway with a model A forceplate Kistler, Amherst, NY at the midpoint. We estimated the force impulse error due to drift by measuring the change in baseline force over the time period of stance and calculating the impulse that would result from integrating this baseline over time. The error was found to be between 0. Kinematic points located at the middle toe, tarsometatarsophalangeal joint, ankle, knee, hip, synsacrum, and the approximate body COM were digitized and filtered as described in ref. We used inverse dynamics to calculate the external moment and work at each joint over the course of stance. The external moment is the magnitude of the cross product between the instantaneous joint-position vector P and the instantaneous GRF vector F g. By convention, an extensor moment and an extending angle change were positive. The joint moment and joint angular velocity were multiplied at each time point to obtain instantaneous joint power and numerically integrated to obtain joint work. Using this approach, the value of work at the last time point is the net work done by that joint. We used the same method to calculate the absolute work done at each joint, except that we took the absolute value of joint power prior to integration. All work values were normalized for size by dividing by the bird's body mass. Average limb stiffness k leg was calculated over the duration of limb compression. Limb compression is a decrease in leg length during an increase in GRF. Thus, k leg was the change in force divided by the change in length during limb compression. Note that k leg was not calculated in the same manner as virtual leg spring stiffness in previous studies 4 , which assumes mass—spring dynamics. During unsteady behaviors, the limb may not maintain spring-like performance. Our measure of k leg avoids potentially incorrect assumptions about locomotor mechanics during unsteady movement. Nonetheless, if the limb does follow spring-like dynamics, k leg calculated here would equal that obtained through previous approaches. We compared limb loading and work performance to the expectations of a simple mass—spring model. The hypothesized mass—spring model is a passive, energy-conservative system that consists of a point mass attached to a mass-less, linear compression spring 3 , 4. This model differs from some recent approaches in that i no small angle assumptions are made in the equations of motion 19 and ii gravity is not ignored This approach necessitates a numerical solution but provides a more realistic approximation of guinea fowl behavior. In the flight phase, the body follows a ballistic path. In steps with a drop in terrain, all model parameters were the same as the level running simulation unless specified otherwise. He writes: It is what we are all aiming for — to keep control of our own lives. It is a fundamental biological urge. But Bradshaw is far from suggesting we slacken in our efforts to train our dogs it is the more brutal training methods he would like to banish. But I wonder how Cesar Millan and his followers will respond to these findings. Millan, America's internationally influential "dog whisperer" has made a television career explaining dog psychology in terms of wolf lore. Bradshaw says: He is now embracing reward-based methods. All that stuff he spouted about wolves was not based on science. Bradshaw favours humane, reward-based training. The latest science shows that dogs learn to "please their owners". It is wonderful to hear this: Bradshaw first went to the dogs — in the best sense — because of his interest in "the science of smell. I used to study ants, wasps, moths… then I thought: Now canine science is a "huge industry — with people working worldwide". The reasons for this include the sequencing of the canine genome, the rise in animal welfare science, increased interest from vets wanting to specialise in dog behaviour and primatologists who can no longer afford to study chimpanzees. Dogs are now used not only for narcotics but to help epileptics able to alert them when they are on the edge of a seizure and to sniff out everything from bedbugs to shark's fins and even certain kinds of cancer. Bradshaw, in his book, follows the dog's nose brilliantly it was intriguing to learn that while dogs love to sniff other dogs they "do not much like being sniffed themselves". He urges us to show "manners" and be aware of our dog's sense of smell. Amateur 32, Videos. Squirting 3, Videos. Lesbian 11, Videos. Mature 2, Videos. Most Popular Tags See All. Porn Videos Recommended. Most Viewed. Top Rated. Watch History. Trending Now. Most Favorited. Recommended Videos See All. Fucking for money PHG-V6. Trending Videos See All. Trending Searches. All Categories. Big Ass. Big Dick. Big Tits. Double Penetration..

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