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Stevens Point, CO, United States

The United States Air Force Academy , is a military academy for officer candidates for the United States Air Force. Its campus is located immediately north of Colorado Springs in El Paso County, Colorado, United States. The Academy's stated mission is "to educate, train, and inspire men and women to become officers of character, motivated to lead the United States Air Force in service to our nation." It is the youngest of the five United States service academies, having graduated its first class in 1959. Graduates of the Academy's four-year program receive a Bachelor of Science degree, and are commissioned as second lieutenants in the United States Air Force. The Academy is also one of the largest tourist attractions in Colorado, attracting more than a million visitors each year.Candidates for admission are judged on their academic achievement, demonstrated leadership, athletics and character. To gain admission, candidates must also pass a fitness test, undergo a thorough medical examination, and secure a nomination, which usually comes from the member of Congress in the candidate's home district. Recent incoming classes have had about 1,200 cadets; historically just under 1,000 of those will graduate. Tuition along with room and board are all paid for by the U.S. government. Cadets receive a monthly stipend, but incur a commitment to serve a number of years of military service after graduation.The program at the Academy is guided by the Air Force's core values of "Integrity First, Service Before Self, and Excellence in All We Do", and based on four "pillars of excellence": military training, academics, athletics and character development. In addition to a rigorous military training regimen, cadets also take a broad academic course load with an extensive core curriculum in engineering, humanities, social science, basic science, military studies and physical education. All cadets participate in either intercollegiate or intramural athletics, and a thorough character development and leadership curriculum provides cadets a basis for future officership. Each of the components of the program is intended to give cadets the skills and knowledge that they will need for success as officers. Wikipedia.

Buehler M.R.,United States Air Force Academy
Medical Hypotheses | Year: 2011

Autism, an incurable neurodevelopmental brain disorder, is a complex psychopathology in which the affected individual cannot effectively self-regulate their sensory inputs toward coherent and focused motor outputs. There have been many hypotheses as to the etiology of autism - genetics, neurotransmitter imbalances, early childhood immunizations, xenobiotic and teratogenic agents, and maternal infection; the disorder can perhaps be studied best under the field of " Psychoneuroimmunology" , which analyzes systemic and psychopathologies from an integrated approach through the combined effects of the nervous, immune, and endocrine systems. Using principles of psychoneuroimmunology along with previously established but yet un-linked scientific principles and observations, this paper proposes a neuroimmune-based mechanistic hypothesis for the etiology of autism that connects elevated levels of maternal pro-inflammatory cytokines to autistic symptoms in her offspring through a logical sequence of events. While both researchers and clinicians often note correlations between pro-inflammatory cytokine levels and autistic symptoms in affected individuals, no specific mechanism has been documented that logically and directly connects the two. I propose that pro-inflammatory cytokines arising from maternal inflammation, infection, and, possibly, autoimmunity, pass through the placenta; enter the fetal circulation; cross the fetal blood-brain barrier (BBB); and cause aberrant neuronal growth and plasticity within the fetal brain via a " cytokine-storm" Microglia and astrocyte stimulation lead to a positive-feedback loop that also facilitates the development of a chronic inflammatory environment within the fetus, pre-disposing it to lifelong comorbid psychiatric and systemic pathologies. Such a mechanism could account for many of the observed symptoms and behaviors of autistic individuals such as hyper-sensitivity to environmental stimuli, object fixation, echolalia, repetitive physical behaviors, chronic enterocolitis, autoimmune disease, and, at the extreme, savantism. The thiazolidinedione pioglitazone (and possibly rosiglitazone), a non-steroidal anti-inflammatory drug (NSAID), which is commonly used to lower blood glucose levels and associated inflammatory markers in patients with diabetes, and histamine receptor blockers, as well as monitoring and limiting sucrose-containing foods, might prove to be effective preventative therapies for the development of autism in the fetus for pregnant women displaying either a cytokine-induced depression or other elevated systemic inflammatory state conditions. © 2011.

Ward B.,United States Air Force Academy | Robin C.,Air Force Research Lab | Dajani I.,Air Force Research Lab
Optics Express | Year: 2012

We present a dynamic model of thermal modal instability in large mode area fiber amplifiers. This model allows the pump and signal optical intensity distributions to apply a time-varying heat load distribution within the fiber. This influences the temperature distribution that modifies the optical distributions through the thermo-optic effect thus creating a feedback loop that gives rise to time-dependent modal instability. We describe different regimes of operation for a representative fiber design. We find qualitative agreement between simulation results and experimental results obtained with a different fiber including the time-dependent behavior of the instability and the effects of different cooling configurations on the threshold. We describe the physical processes responsible for the onset of the instability and suggest possible mitigation approaches. © 2012 Optical Society of America.

Andersen G.,United States Air Force Academy
Applied Optics | Year: 2010

We present results of research into the design and construction of membrane photon sieves as primaries for next-generation lightweight space telescopes. We have created prototypes in electroformed nickel as well as diazo and CP-1 polymer films. In two such cases, diffraction-limited imaging performance was demonstrated over a narrow bandwidth. © 2010 Optical Society of America.

Ward B.G.,United States Air Force Academy
Optics Express | Year: 2013

A model of transient modal instability in fiber amplifiers is presented. This model combines an optical beam propagation method that incorporates laser gain through local solution of the rate equations and refractive index perturbations caused by the thermo-optic effect with a time-dependent thermal solver with a quantum defect heating source term. This model predicts modal instability a fiber amplifier operating at 241, 270, and 287 Watts of output power characterized by power coupling to unseeded modes, the presence of stable and unstable regions within the fiber, and rapid intensity variations along the fiber. The instability becomes more severe as the power is increased. © 2013 Optical Society of America.

Ward B.,United States Air Force Academy
Optics Express | Year: 2016

A theory of photodarkening-induced quasi-static degradation in fiber amplifiers is presented. As the doped core of a fiber photodarkens and continues to absorb more power converting it to heat, the intensity grating created by higher order mode interference with the fundamental mode moves toward the input end. This creates a persistent absorption grating that remains phase-shifted from the modal interference pattern. This leads to power transfer from the fundamental mode to a higher order mode with a very small frequency offset that occurs on a time scale of minutes to hours. This process is modeled in large mode area step index and photonic crystal fibers and is found to produce reasonable threshold values. © 2016 Optical Society of America.

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