Alzheimer\u27s Disease: The Silver Tsunami of the 21st Century

Alzheimer\u27s disease (AD), a fatal progressive neurodegenerative disorder, has no cure to date. One of the causes of AD is the accumulation of amyloid-beta 42 (Aß42) plaques, which result in the onset of neurodegeneration. It is not known how these plaques trigger the onset of neurodegeneration. There are several animal models developed to (i) study etiology of disease, (ii) look for genetic modifiers, and (iii) identify chemical inhibitors that can block neurodegeneration and help to find cure for this disease. An insect model of Drosophila melanogaster has also provided new insights into the disease. Here we will discuss the utility of the Drosophila eye model to study Alzheimer\u27s disease

Electron-Impact Ionization of Laser-Aligned Atoms -- Contributions from Both Natural and Unnatural-Parity States

Synopsis. The progress of experimental and theoretical measurements for (e,2e) ionization cross sections from laser-aligned atoms is presented here. It is found that both natural and unnatural parity contributions must be included in the models to emulate the experimental data

Natural & unnatural-parity contributions in electron-impact ionization of laser-aligned atoms

Differential cross section measurements from laser-aligned Mg atoms are compared to theoretical calculations using both time dependent and time-independent formalisms. It is found that both natural and unnatural parity contributions to the calculated cross sections are required to emulate the data when the state is aligned out of the scattering plane

Murine obscurin and Obsl1 have functionally redundant roles in sarcolemmal integrity, sarcoplasmic reticulum organization, and muscle metabolism.

Biological roles of obscurin and its close homolog Obsl1 (obscurin-like 1) have been enigmatic. While obscurin is highly expressed in striated muscles, Obsl1 is found ubiquitously. Accordingly, obscurin mutations have been linked to myopathies, whereas mutations in Obsl1 result in 3M-growth syndrome. To further study unique and redundant functions of these closely related proteins, we generated and characterized Obsl1 knockouts. Global Obsl1 knockouts are embryonically lethal. In contrast, skeletal muscle-specific Obsl1 knockouts show a benign phenotype similar to obscurin knockouts. Only deletion of both proteins and removal of their functional redundancy revealed their roles for sarcolemmal stability and sarcoplasmic reticulum organization. To gain unbiased insights into changes to the muscle proteome, we analyzed tibialis anterior and soleus muscles by mass spectrometry, uncovering additional changes to the muscle metabolism. Our analyses suggest that all obscurin protein family members play functions for muscle membrane systems

Standing Weight Perception across Unweighted Conditions in a Lower Body Positive Pressure Treadmill

Lower body positive pressure treadmills (LBPP-TM) provide assistive body weight support to the user by forcing air into an inflatable chamber in which the user is secured. The result of this positive pressure can be experienced as a lift to the user. The degree of chamber air pressure (CAP) determines the amount of supportive lift provided with greater and lesser CAP producing more and less lift, respectively. Exercise studies consistently report lower effort perceptions with greater CAP which suggest a reduced physiological and mechanical strain on the body. What is less well known is the effect on resting perceptions of standing weight (SWP). The purpose of this investigation was to examine the perception of resting standing weight across four different weighted conditions in a LBPP-TM. Nine participants (6 female; overall age: 21.3±1.9 years) stood in a LBPP-TM under the following order of body weight set (BWset) conditions: 100%BWset, 70%BWset, 35%BWset, 90%BWset. A portable Davis Vantage weather station barometer measured CAP inside the inflatable chamber and a 10-cm visual analogue scale measured SWP. Repeated measures analysis of variance evidenced significant changes across CAP (100%BWset: 767.5±4.9 mmHg; 70%BWset: 780.0±3.0 mmHg; 35%BWset: 793.5±3.0 mmHg; 90%BWset: 776.4±7.0 mmHg; all ps ≤ 0.001) except for the 70%BWset and 90%BWset conditions (p = 0.486) and within SWP (90%BWset: 8.8±1.4 cm vs. 70%BWset: 5.8±2.9 cm, p = 0.011; and 35%BWset: 4.6±3.2 cm, p = 0.007) experimental conditions. LBPP-TMs appear to provide robust manipulations of perception across different experimental contexts. Similar to findings from exercise studies, greater CAP and its resultant lift produced significant reduced perceptions of standing weight while at rest.https://digitalcommons.cortland.edu/slides/1025/thumbnail.jp

Blood Pressure Responses during Three Unweighted Conditions in a Lower Body Positive Pressure Treadmill

During exercise, lower leg muscle activation has been shown to increase venous return, exercise cardiac output, and arterial blood pressure (BP). Here we investigate BP at rest, with an increase in lower body pressure by unweighting volunteers in a lower body positive pressure treadmill (LBPP-TM). The purpose of this study was twofold; to determine if BP changes while standing over five-minute stages in response to four conditions. Nine participants (21.3±1.8 years) stood in a LBPP-TM in the following ordered conditions: 100%BWset (no unweighting, control), 70%BWset, 35%BWset, and 90%BWset (35%BWset is the greatest unweighted condition). A SunTech® automatic BP cuff measured systolic and diastolic BP (SBP and DBP, respectively). SBP and DBP was measured once during 100%BWset and averaged over the five-minute stages during 70%BWset, 35%BWset, and 90%BWset. A portable Davis Vantage weather station inside the chamber measured chamber air pressure (CAP). Repeated measures analysis of variance evidenced significant differences in only SBP (p = 0.006) at 100%BWset (no unweighting) and 90%BWset (129±11 mmHg and 120±8 mmHg, respectively). DBP did not show any significant differences across conditions (ps \u3e 0.091). CAP at 100%BWset (767.5±4.9 mmHg) was lower compared to 70%BWset (780.0±3.0 mmHg), 35%BWset (793.5±3.0 mmHg), and 90%BWset (776.4±7.0 mmHg) (p\u3c0.001, p\u3c0.001, and p=0.001, respectively). 35%BWset CAP was also higher than 70%BWset and 90%BWset (ps\u3c0.001 for both), but 70%BWset and 90%BWset CAPs were not different (p = 0.486). The initial findings suggest a quick reduction in CAP (35%BWset to 90%BWset) may decrease SBP below starting levels at 100%BWset. Though the sample consists of healthy, young adults and there was only a 9.0 mmHg decrease in SBP, individuals who are intolerant to SBP changes or older adults may need a slower reduction in CAP from highly unweighted conditions to account for SBP changes as they return to baseline CAP.https://digitalcommons.cortland.edu/slides/1022/thumbnail.jp

(e,2e) Ionization Studies of N₂ at Low to Intermediate Energies from a Coplanar Geometry to the Perpendicular Plane

Synopsis. The progress of experimental and theoretical measurements for (e,2e) ionization cross sections from Nitrogen molecules is presented. Results are given for energies from ~10 eV above the ionization potential (IP) through to ~100 eV above the IP for the 3σg, 1πu and 2σg states

At-grade stabilization structure impact on surface water quality of an agricultural watershed

Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as a paired watershed study, in which monitoring stations were installed on the perennial streams draining both control and treatment watersheds. Linear mixed effects statistics were used to determine significant changes in nutrient concentrations before and after installation of an AGSS. Results indicate a significant reduction in storm event total P (TP) concentrations (P = 0.01) within the agricultural watershed after installation of the AGSS, but not total dissolved P (P = 0.23). This indicates that the reduction in P concentration is that of the particulate form. Storm event organic N concentrations were also significantly reduced (P = 0.03) after the AGSS was installed. We conclude that AGSS was successful in reducing the organic and sediment bound N and P concentrations in runoff waters thus reducing their delivery to nearby surface waters

At-grade stabilization structure impact on surface water quality of an agricultural watershed

Decades of farming and fertilization of farm land in the unglaciated/Driftless Area (DA) of southwestern Wisconsin have resulted in the build-up of P and to some extent, N, in soils. This build-up, combined with steep topography and upper and lower elevation farming (tiered farming), exacerbates problems associated with runoff and nutrient transport in these landscapes. Use of an at-grade stabilization structure (AGSS) as an additional conservation practice to contour strip cropping and no-tillage, proved to be successful in reducing organic and sediment bound N and P within an agricultural watershed located in the DA. The research site was designed as a paired watershed study, in which monitoring stations were installed on the perennial streams draining both control and treatment watersheds. Linear mixed effects statistics were used to determine significant changes in nutrient concentrations before and after installation of an AGSS. Results indicate a significant reduction in storm event total P (TP) concentrations (P = 0.01) within the agricultural watershed after installation of the AGSS, but not total dissolved P (P = 0.23). This indicates that the reduction in P concentration is that of the particulate form. Storm event organic N concentrations were also significantly reduced (P = 0.03) after the AGSS was installed. We conclude that AGSS was successful in reducing the organic and sediment bound N and P concentrations in runoff waters thus reducing their delivery to nearby surface waters

High Contrast Vacuum Nuller Testbed (VNT) Contrast, Performance and Null Control

Herein we report on our contrast assessment and the development, sensing and control of the Vacuum Nuller Testbed to realize a Visible Nulling Coronagraphy (VNC) for exoplanet detection and characterization. Tbe VNC is one of the few approaches that works with filled, segmented and sparse or diluted-aperture telescope systems. It thus spans a range of potential future NASA telescopes and could be flown as a separate instrument on such a future mission. NASA/Goddard Space Flight Center has an established effort to develop VNC technologies, and an incremental sequence of testbeds to advance this approach and its critical technologies. We discuss the development of the vacuum Visible Nulling Coronagraph testbed (VNT). The VNT is an ultra-stable vibration isolated testbed that operates under closed-loop control within a vacuum chamber. It will be used to achieve an incremental sequence of three visible-light nulling milestones with sequentially higher contrasts of 10(exp 8), 10(exp 9) and ideally 10(exp 10) at an inner working angle of 2*lambda/D. The VNT is based on a modified Mach-Zehnder nulling interferometer, with a "W" configuration to accommodate a hex-packed MEMS based deformable mirror, a coherent fiber bundle and achromatic phase shifters. We discuss the laboratory results, optical configuration, critical technologies and the null sensing and control approach