The study used an amputee who still had enough of the muscle left in his upper arm to help control his movement and different daily tasks using the prostheses. During all experiments, the amputee was visually and acoustically isolated, so the results would be only caused by the hand prosthesis. The experimenters took TIME devices and surgically implanted them in the ulnar and medial nerve, because they control most of the palm and the finger sensory fields. These TIME devices connected to mechanical sensors on sensors located in the prosthesis. This then turned the information received into electrical signals that the nerves in the arm received. They used different currents to test different responses. As they increased the current, the neurons firing rate increased as well.
Methods and Materials
Two plates containing PpNH4 media were supplied by Professor Bezanilla’s Laboratory. The media contains the following macro nurtients: MgSO4 1.03mM, KH2PO4 1.86 mM, Ca(NO3)2 3.3 mM, Di-ammonium tartrate 2.72 mM, and FeSO4 45 μM. The media also contains the following in trace amounts: H3BO3 9.93 μM, CuSO4 220 nM, MnCl2 1.966 μM, CoCl2 231 nM, ZnSO4 191 nM, KI 169 nM, and NaMoO4 103 nM. The growth solution was mixed with 7 g/L of agar to create a solid growth media. This growth mediate works best with the moss Physcomitrella patens, but was used in this experiment as a good enough growth medium for an unknown species of moss.
Temperature Recording Equipment:
An indoor/outdoor thermometer was placed next to the specimens in the appropriate location to accurately collect temperature data for both conditions. Temperatures were recorded in degrees Fahrenheit. The temperature was monitored and recorded throughout the day by various member of the BCRC staff. Monitoring of the temperatures started on the morning of Tuesday, April 18th and ended on Friday, April 21st at 2:00 pm.
The moss samples were collected from the Durfee Conservatory on the University of Massachusetts Amherst campus. Permission was granted by the staff member in charge and the collection was conducted by the staff member. The collected moss was placed on the two growth medium plates. Each large moss specimen was further divided into one large piece and five smaller sprouts of varying size of a smaller number of individual moss plants. These smaller pieces were embedded in the agar/growth medium. Each plate was photographed with a quarter as a size reference for evidence of initial size and condition.
One plate was placed in the window sill inside the BCRC and the other was placed just outside on the same window sill. The window was kept closed through the entirety of the experiment. The placement of the two plates was Friday, April, 14th at approximately 2:20 pm.
The experiment ended at 2:00 pm on Friday, April 21st. The moss plates were again photographed with a quarter as a reference for size. Each plate was analyzed for growth and overall condition.
In my physics class the other day my professor had mentioned that Saturn’s and Jupiter’s moons may be habitable. NASA has been watching these moons for quite some time now and shocking new evidence has come into play. They used a mass spectrometer that helped detect an ample amount of hydrogen molecules in the water that sits beneath its icy surface. They think that this hydrogen came from a hydrothermal reaction, which means that methane could be forming in their ocean as well. It reflects a lot like our planet. These moons have a potential of microbes existing and other organisms which can branch of and become a vast amount of species. Most of our species originated from water, so to know that there is capability of species now living in the ocean on their moons, it shows potential for life.
A Go/No-Go task will be used to measure the cognitive functioning of the child, specifically inhibitory control. During the Go/No-Go task, children will be told that they need to catch animals that have escaped from a zoo. To catch the animals, they are to press a button on a mouse as quickly as possible. They are instructed to catch all animals except for the chimpanzee because the chimpanzee is helping to catch the other animals. Children will have one practice round and two sessions of the actual task. If children click the mouse when the chimpanzee pops up, they are reminded not to catch him in order to help with the task at hand. Additional questionnaires will be used to assess the behavior and sleep in the sample tested.
The task of the two patients of the study describe how electrical stimulation is distinct at varying levels of intensity. The researchers developed a value known as activation change rate (ACR) that represents the “total population spike count in the activated neural population.” It measures the aggregate intensity of the neurons in width and amplification to get a sense of how intense each iteration of electrical stimulation is perceived as. They found that population spikes in nerves correlate with the magnitude of touch.
In my evolution class recently we learned about canes beetle and toads. The plant, Sugar cane was planted in a lot of tropical places around the world and it brought about these beetles that would prey on it. It would be such a heavy infestation that you could see swarms of beetles flying around the sugar cane. For a long time, there wasn’t a good solution to get rid of them, but biologists thought of an organism that would help rid them of this beetle. They used a toad as a biological pesticide that would actually consume these bugs. These toads are originally from South Africa, but they have been established in other places like South Florida, Hawaii, and Australia. They proliferated like crazy in Australia. These toads are capable of eating anything that fits in their mouth, and they were also very hard to be predated on since anything that ate it would die, as they had huge poisonous glands next to their head. What made this toad inefficient for the job they needed for was the fact that they were nocturnal and the cane beetles were diurnal, so they were actually really horrible at reducing the number of beetles infesting on sugar cane. They were great at killing other things, so through that their population started to increase rapidly through the coast of Queensland and there was no way stop them. Now throughout hundreds of years there has been a reduction in their size (of toads), toxicity, and their hind legs have been growing longer in proportion to their shrinkage. This is due to the fact that some of the snakes that feed on the toad. Some of the snakes that feed on this toad have also become increasingly larger, so they can assimilate more of the poison without dying, and their heads have gotten smaller so they can eat smaller toads and get smaller amounts of poison.
The moss specimen examined, regardless of location, were capable of surviving desiccation and successfully rebounded in greenness.
Specimens from South, East, and West microclimates generally rebounded at similar rates, indicating that such subtle changes in microclimates may either not affect rebound success or was not detectable using our methodology.
Though the North facing specimen experienced the least successful rebound, we cannot conclude that this is solely a result of its original microclimate and that North facing mosses are generally not as successful.
- A more extensive comparison between North, South, West, and East facing moss samples from multiple trees should be conducted to determine if a different tree location produces a significant effect in more variable locations (with more extreme sun exposures depending on orientation).
Janpanese scientists have created a chemical bath to treat plants that reduces the visible chloropasts within the plant. Day to weeks after the treatment, the plant become virtually transparent, allowing scientists to see the inner workings of the plant in a live and real-time manner. Researchers introduce fluorescent proteins that target specifc areas or proteins within the plant while its still alive. The plant is then killed with formaldehye, sectioned, and then frozen. These frozen sections can be further cut into cross section to be examined under the microscope. This method has been tested on rice, tobacco, tomato, cucumber, moss, and other flowering plants.
When protiens interact with DNA, they interact on the major groove because the minor groove is too small. Nucleotides make up the DNA strand and form a polymer. Each nucleotide contains a phosphate group, a sugar, and a nitrogenous base. Base pairing occurs where A attaches to T and G attaches to C. The 1’ carbon is attached to base all the way to 5’ carbon at the phosphate in the sugar. This is important to the directionality of the polymer. The 3’ end of DNA/polymer is on the sugar, 5’ is where the phosphate is exposed. Polymers attach by hydrogen (non-covalent) bonding to create the DNA strand. The DNA runs antiparallel fashion. A primer is required for DNA polymerase to begin adding nucleotides.
RNA has a difference in its sugar as compared to DNA. The 2’ carbon has OH coming off of it, DNA has 2’ H. RNA is less stable, the oxygen allows it to act as a catalyst in chemical reactions. RNA can make intramolecular reactions on itself, like a protein, but structures are limited (ribosomes & splicasome). RNA has uracil instead of thymine. When DNA is damaged, cytosine can change to uracil and base paring then does not occur properly. It is possible for double stranded RNA to be formed and DNA can bind with it. It is a hybrid double helix, a slightly different shape. DNA replication is semi-conservative (a mix). Originally there were three methods thought up, Semi-conserve, Conservative and dispersive.
One strength of this study is that they were able to produce a more realistic hand property with the bidirectional control in which he can feel the stimulation but also respond to it. They also performed over 700 trials to confirm the shape recognition experiments to receive the results they did. Another strength is that they used a current that was below pain threshold, so that was beneficial for the participant. On the other hand, even with the strong strengths, there were a few weaknesses with this study. They performed this study with only one participant, specifically one who was able to use prostheses very well, so one cannot really tell if the same experimental results will come with a higher sample of participants. Another weakness is that the equipment used is very large and not very mobile. The experiment only lasted about 7 days, so there is no telling whether the patient would retain the movement and object recognition that he learned through experience. A final weakness about this study is that the participant was able to feel sensation for a week but then got it taken away quickly. This could be psychologically difficult for him to get his hand senses taken away again. The conclusion taken away from this study is that there is a good possibility of this prosthesis, given the high success rates from the experiments. Some further experiments can definitely be done given the weaknesses of the study. The next step would be to repeat this with a higher number of participants to increase the validity of the results of this study. Another step that could be taken would be to increase the length of the experiment past just a week. More tasks could be added to the experiments with a wider variety of objects. One final step to be taken would be to figure out ways to shrink the machinery to make the study more mobile.