ekirchner's blog

The activity of P. occidentalis, harvester ants, has been shown to enrich soil nutrients around their mounds due to the ants’ movement of particles¹  from soil nearby. The rudimentary soil composition in certain areas has also influenced the density and variation of ant populations²  present in that environment. In our experiment, the effects of salinity on the harvester ants burrowing behaviors were tested. 

Hypothesis: The ants will burrow more in the sand where the salinity is lower.

Half of an ant farm was filled with regular, untouched sand, while the other half was filled with sand where the salinity was manipulated to be that of seawater (35 ppt). Eight ants were added to the farm and left to burrow for 6 days, while every few days their food and water were restocked. The burrowing  length results and general observations were recorded and the Mann-Whitney U test was used to analyze the results. 

The activity of P. occidentalis, harvester ants, has been shown to enrich soil nutrients around their mounds due to the ants’ movement of particles¹. The rudimentary soil composition in certain areas has also influenced the density and variation of ant populations². In our experiment, the effects of salinity on the harvester ants burrowing behaviors were tested. 

Hypothesis: The ants will burrow more in the sand where the salinity is lower.

Half of an ant farm was filled with regular, untouched sand, while the other half was filled with sand where the salinity was manipulated to be that of seawater (35 ppt). Eight ants were added to the farm and left to burrow for 6 days, while every few days their food and water were restocked. The burrowing results and general observations were recorded and the Mann-Whitney U test was used to analyze the results. 

Each group received 30 seeds of the same soybean species, totalling 6 species and 180 seeds total. One set of 10 seeds served as a control, 10 were nicked with a small needle, and 10 were manipulated so that the seed coat was completely removed.

We placed each set of seeds in a large petri dish with a wet paper towel. The dishes were labeled with the type of seed and the treatment that the set received. 

The seeds were covered and left to sit for 3 ½ consecutive days, and we checked them for germination at 8 am and 7 pm every day. Each group member re-added water to a paper towel if it had dried out. We recorded the amount of seeds in each dish that had no change, began germination, were germinating, and have stopped germinating at every check-in time. 

The gravitational pull of the Moon influences our oceans' tides more than the Sun because it is much closer to the Earth. High tides are created by the moon pulling water up, and low tides are created by water moving away to satisfy those high tides. High and low tides occur almost twice per day, but not quite. This is due to the fact that one solar day is 24 hours, but a lunar day, the time it takes the Earth to reach the same position relative to the Moon, is about 24 hours and 50 minutes. The tides follow a lunar day schedule because the gravitational pull of the Moon is almost twice as strong as that of the Sun. 

The change between tides, also known as the flood tide and ebb tide, are gradual. This means that the line between the high and low tides is a gray area, so one cannot exactly predict the length of each. The speed of water flow varies during te flood and ebb eriods, and it also varies from place to place.

Immunostaining is the use of antibody-based methods for detecting specific proteins within a cell. In electron microscopy, immunostaning can be especially useful because elctron microscopy uses very, very thin slices of samples, and proteins can be marked and identified under this method using heavy metal particles. While useful, staining in EM is very difficult, as membrane conservation and replicability is next to impossible. 

In general, immunohistochemistry is used to stain cells in identifying structures, either using fluorescent dyes or non-fluorescent methods like enzymes. Light microscopy can be used to view the effects of the staining, reducing the costs compared to EM. Like EM, replicability and fixation protocols are still being adjusted. 

Recently in my lab I have been segmenting light sheet microscopy images of the entire slug brain. The animal used was an adult sea slug with a fully developed nervous system. Sea slugs are interesting neural subjects because their digestive system extends right through the brain. The adult slug brain contains 2 rhinophore ganglia, 2 cerebral pleural ganglia, 2 pedal ganglia, and 2 buccal ganglia. I have also used the software to identify the eye in these images, the optic lobe, and the statocyst, a small sensory organs that aids in balance and orientation. The different ganglion lobes are connected to each other via commisures, although these are harder to see than the bright ganglia in the light sheet images. 

In addition to brain segemntation, I am also completing behavioral hormone experiments in juvenile sea slugs. The hormones in question have already been tested in adult slugs, so hopefully the results of my experiments can give some insight about sensory organ development in this species. 

This poster, titled “Permanent Chemotherapy Induced Alopecia in Young Breast Cancer Patients” does not have an attractive design. White space and alignment is good but the coloring is poor and does not catch your eye. The font and typography is consistent and clean throughout the poster. The layout of the poster is appropriate, except for the lack of an abstract. I do not think posters usually have abstracts, and that the conclusion usually just summarizes everything. Each section is focused and clear with the direct message presented appropriately.

            The writing is presented in bullet points, something that makes the main information easier to catch but looks a little unprofessional. There are no typos on this poster, and overall it seems correct and informative about the findings of alopecia in breast cancer patients. I think the only things I might change about it are the coloring and possibly adding one more figure on the left side. 

Performing this experiment could lead us to results that will benefit farmers and society from an agricultural standpoint. If the results turn out as predicted and seeds with no seed coat germinate faster, we could apply this information to crop production. The application of the seed coat removal technique in agriculture could benefit people economically and environmentally. If the results do not turn out as predicted, i.e. the seeds fail to germinate or it has no effect on germination rates, this will help us understand crop production further to make better decisions in the future. We could then conclude if the seed coat is or is not important for success rates of plants and crops, and use this information to our advantage in the future of agriculture.

When you order live ants, they come in a little tube with only one small carrot piece. It is important to put them in a suitable enclosure as soon as they are delivered to increase their chances of survival. An ant farm ordered online usually comes with all the necessary pieces as well as some small bags of the sand. The ant farm must be turned upside down, with the bottom removed, in order to add the sand, and as much as possible should be added to give the ants more room to roam. Once all the sand is added to the ant farm, the bottom piece can be placed back on and the farm can be turned upright. Next, water must be added to the sand, around 60 mL, by pouring it through the top. All the sand should be dampened, but not soaked, so that the ants have water to survive as well as dig stable tunnels. A small cotton ball is usually blcoking the entry way to the ant farm, so a long probe is provided to poke the cotton through as well as push it halfway down into the sand to encourage them to burrow. Lastly, before adding your ants, small pieces of food should be placed inside. Cut up carrots or apples are easily inserted into the farm, and they are better to place right on top of the sand to encourage the ants to go down there and start digging. Always make sure your ants have plenty of food and water, and the farm is kept at a suitable temperature. 

Gliding assays are in vitro methods to examine the movement of microtubule motors. To perform a gliding assay, a cover slip is placed on a slide and you add purified kinesin motors. The motors stick to the bottom of the cover slip, and you add microtubules and taxol. You can then observe the motors moving the microtubules around the slide. Taxol is important because it binds to and stabilizes the microtubules, preventng them from depolymerizing.