The weaknesses of this study involve the mortality rate of their test subjects. I was shocked to hear in class that somewhere around 25% of the mice died during testing from seizures. This makes sense considering they are just activating a whole bunch of neurons with a simple injection. It makes me wonder whether this could be effecting the behavior of the mice that did survive the experiment. For example, could their fear response with and without CNO be a natural anxiety developed from brain damage from the experiment? Secondly, the results from Fig 1D are somewhat concerning as it takes about an hour for the mice to respond to CNO which could mess with results. Additionally, the results rarely ever revealed over a 50% freezing which are nor very strong results. Despite that, because of their control experiments, and logical experimental outline, the results are still valid, just not as strong as we could hope for.
Downy Woodpecker (Picoides pubescens) are adept at climbing trees and pecking for insects such as beetle larvae, ants, caterpillars, earworm, and apple borers which burrow inside of wood or tree bark. Part of their diet consists of plant material, berries and grains. They move horizontally and downwards on trees rapidly. It has a specialized beak and skull that redirects most of the strain from repeatedly striking trees, into the rest of the body, instead of the head. They take frequent breaks in drilling to prevent brain damage caused by overheating. This is different than the Upland sandpiper (Bartramia longicauda) which feeds on mostly insects, including weevils, beetles, grasshoppers, and crickets. It feeds while walking along the ground.
Humans have evolved to become more fragile and we’re less capable of labor as technology has caught up and allowed us to live lives with less physical labor. The increase in the size of our brains also requires a lot of energy to be put into the brain, and require more time for the brain to become mature. So as time goes on, and our brains continue to evolve and become bigger as technology accompanies our needs more and more, will we eventually get to a point where humans cannot walk anymore, because technology will accommodate that for us? Will it ever get to a point where we will be living the same way as the people in that scene of Wall-E, where everybody is permanently stuck in a moving chair with a screen in front of them at all times? Personally, I think we’ve reached a balance between technology and fitness, and we’re able to enjoy the physical aspects of being human, while being able to enjoy the accommodations that technology has for us.
Photoshop, Lightroom, Ableton, Microsoft Office, all of these programs require hefty prices in order to gain accessibility to these programs. These programs are just a few examples of the core programs required for career options such as photography, music, creating a startup, and more. A lot of these career options that are in the “art” category of career choices, are often overlooked at as “payable via exposure”. What this means, is that instead of people paying money in order to play someone’s music or show someone’s art at their restaurant or exposition, they instead offer “exposure” as if that completely covers all monetary requirements to keep paying for these programs, as well as their need for shelter and food. To give an idea as to how expensive these programs are, Photoshop and Lightroom can be bought as a package for 11$/month, but you can never own the programs; meaning the programs must always be bought off every month and this fee will always exist. Ableton for the LITE version (the version with the least add-ons) costs $400, while the pro version costs $1100+. Microsoft Office can cost anywhere between $240 to $440. These costs are expensive and to “give exposure” as if it’s enough, is evidently not enough purely based on exposure alone.
Birds have a special organ called the syrinx, that allow them to sing the way they sound. It is located on the trachea to produce sound. It is similar to the mammalian larynx but the way air is used is different. In the syrinx, 100% of the air is converted to sound where the larynx only uses 2%. The vibrated air passes through the syringeal passageway to project on the tympaniform membrane. This vibration is the result of how birds can vocalize. The syrinx is a complex organ itself but the muscle attached around it is also complex. There are layers of muscle structures to create fine adjustment of vibration. The sound produced by the syrinx can be filtered to change the loudness and the pitch. The experiment was done to prove that sound travels faster than helium atmosphere showed sound produced in such atmosphere had different pitch and frequency than the sound produced in our normal atmosphere. The understanding of syrinx and physics of sound helped scientists to learn more about vocalization.
Researchers tested a hypothesis that an inflammation in a chemical pathway would cause schizophrenia. Researchers targets tryptophan, which is a precursor for the development of kynurenic acid. Therefore, it blocks a key glutamate receptor in the brain. What was found was that the astrocytes were providing nutrients to neurons with elevated of kynurenic acid. The elevated levels of kynurenic acid causes inflammation which is a major part of schizophrenic symptoms.
Glucose growth condition is typically a form of osmotic stress. When a gene, SFAR4, was knocked out in Arabidopsis, the mutant plant was susceptible to glucose osmotic conditions and had lower germination rates than overexpression transgenic lines and wild-type. Under mannitol osmotic stress conditions, germination rates in mutant plants were not significantly lower than those in overexpression transgenic lines and wild-type. This indicates that the susceptibility to glucose is not due to osmotic stress but due to the mutated gene.
In this lab, several chemical tests and MP determination were performed on an unknown compound to determine the structure and the identity of the unknown. Also, an HNMR of the unknown was analyzed to confirm the identity. In the first test, unknown #36 was mixed in 2,4-DNP in a test tube. Two drops of the unknown were mixed. A yellow-orange precipitate formed, indicating the carbonyl group is not conjugated. Schiff's test was then performed where unknown #36 (1 drop) was added to the schiff's reagent (0.7 mL). A pale pink color was observed, indicating that unknown must be a ketone. The final test was the iodoform, where the unknown (1 drop) was dissolved in 1,2-dimethoxy ethane (0.5 mL), 3M NaOH (0.5 mL) and iodine solution (0.75 mL) and mixed thoroughly. A yellow precipitate formed, indicating it was a ketone.