Amyotrophic Lateral Sclerosis

The word amyotrophic is derived from Greek, and means “without nourishment to muscles”, lateral means to the sides and sclerosis means hardened (“What is ALS?,” n.d.). First described by Jean-Martin Charcot in the 1800s, Amyotrophic Lateral Sclerosis (ALS) is a progressive degenerative motor neuron disease. Motor neurons are very important cells, and extremely unique since they can be very long with some motor neurons having a length of over a meter (“Disease Mechanisms,” n.d.). About 5-10% of the cases of ALS are inherited, which is known as familial ALS or fALS, and it is known as autosomal dominant in these patients (“Amyotrophic lateral sclerosis”, 2019; “ALS - amyotrophic lateral sclerosis,” n.d.). In the 1950s, there was an extraordinarily high rate of ALS diagnosis in Guam. There were about fifty cases of ALS in a group of 25,500 people, five of which were classified as familial cases. This was an indication to researchers that there may have been an unknown underlying cause. A few years later the researchers defined it as familial ALS with dominant inheritance (Mathis, Goizet, Soulages, & Vallat, 2018). In the other cases of this disease, known as sporadic ALS (sALS), the cause is unknown (“Amyotrophic lateral sclerosis (ALS)”, 2019). In the United States it is often referred to as Lou Gehrig’s disease, from the famous New York Yankee baseball player who had this disease in the 1940s. This specific type of motor neuron disease is the most common form of motor neuron disease in adults (“Amyotrophic lateral sclerosis”, 2015). Motor neurons are the neurons that control movements such as walking, talking, breathing, swallowing and others. These nerve cells expand from the brain to the spinal cord and then to muscles throughout the body that control voluntary muscle movement. When the motor neurons die, the brain can no longer initiate and control muscle movement due to lack of contact (“What is ALS?,” n.d.). This disease causes the motor neurons to slowly degenerate and, eventually, become hardened and die. Without neuronal stimulation to the muscles, the muscles begin to atrophy. ALS affects the motor neurons, cerebral cortex, brainstem and spinal cord (“ALS - amyotrophic lateral sclerosis,” n.d.)

Fearless: Anastasia Maisel

Working to create a meaningful, respectful, and community-minded Day of Service in honor of Gettysburg College student Emily Silverstein ’11, and continually involved in different farming and food initiatives in the Gettysburg area to promote food justice and environmentally friendly farming practices, Anastasia Maisel ’14 fearlessly gives her time, energy, and passion to promoting social justice on and off campus. [excerpt

Elementary approach to closed billiard trajectories in asymmetric normed spaces

We apply the technique of K\'aroly Bezdek and Daniel Bezdek to study billiard trajectories in convex bodies, when the length is measured with a (possibly asymmetric) norm. We prove a lower bound for the length of the shortest closed billiard trajectory, related to the non-symmetric Mahler problem. With this technique we are able to give short and elementary proofs to some known results.Comment: 10 figures added. The title change

Factorization of Multiparticle Scattering in the Heisenberg Spin Chain

We give an explicit proof within the framework of the Bethe Ansatz/string hypothesis of the factorization of multiparticle scattering in the antiferromagnetic spin-1/2 Heisenberg spin chain, for the case of 3 particles.Comment: 9 pages, LaTeX, no figure