427 research outputs found
Cultural Autobiography- Elena Amonette
This cultural autobiography represents the story of my life, particularly how being biracial has stood to impact my life. In this essay, I detail the events which led to my mother, a Laotian immigrant, to America and the influence of my heritage on the lives of our family. This essay was a final project for my Honors Asian Culture Seminar and is the intersection of both my in-class cultural education and life experiences. In writing this piece, I have tried my best to showcase my unique perspective on life and how these experiences emphasize the importance of cultural diversity in all of our lives
Examining the effect of random student drug-testing in a high school setting
The purpose of this exploratory investigation was to ascertain the effectiveness of decreasing drug use in a high school setting by implementing a random student drug-testing program. High school students who were involved in any athletic or extracurricular activities or who were applying for a parking permit in one local school were required to obtain parental permission to participate in a random student drug-testing program. Approximately once a month, an outside agency performed confidential and private urinalysis screening at the high school on 10-14 students whose names were chosen randomly using a computer program. If a urine test was positive for any drug, the contracted company\u27s physician reviewed the results of the finding and notified the parents of the results. Outcome variables were students\u27 anonymous responses on the American Drug and Alcohol Survey, which was administered yearly. The introduction of the random student drug-testing program was associated with decreased self-report use of drugs and alcohol within the first year of implementation. Increased self-reported drug and alcohol usage was observed within each cohort of students as they progressed to the next grade level. Implications for high school policy for random student drug-testing are discussed
The role of structural iron oxidation in the weathering of trioctahedral micas by aqueous solutions
An integrated approach involving several experimental and analytical techniques was used to study the role of structural iron oxidation in the weathering of trioctahedral micas by aqueous solutions. Analytical techniques for the assay of Fe(II) by oxidimetry and for the estimation of octahedral sheet cation occupancies by x-ray diffraction were developed. A weathering apparatus to allow the continuous treatment of micas by fresh aqueous solutions was also developed. This apparatus was used to treat the 10- to 20-[mu]m size-fractions of three trioctahedral micas (a phlogopite, biotite, and siderophyllite) by aqueous solutions that varied in their tendency to promote oxidation, dissolution, and interlayer expansion reactions in the micas. The treatments generally involved 1 M KOAc(pH 4.7)-0.1 M K[subscript]2 EDTA solutions with or without 25% H[subscript]2O[subscript]2 as an oxidant, and were applied at 80°C for periods as long as 36 days. Experiments with deuterated mica samples and with K-depleted samples in 1 M Na solutions were also conducted. The time-dependence of the dissolution of the micas was determined by measuring the amounts of Al, Mg, and Fe in the effluent solutions after different periods and calculating apparent rate constants (ca. 10[superscript]-4 s[superscript]-1) using a heterogeneous kinetic model. Ratios of the rate constants obtained in different solutions were used to estimate the extent of exfoliation of the micas by the weathering treatments. Structural and chemical analyses of the micas before and after treatment were performed by conventional techniques (x-ray diffraction, infrared spectroscopy, Mossbauer spectroscopy) in addition to the two techniques that were developed. These analyses provided strong evidence for the deprotonation of structural hydroxyls and ejection of octahedral cations during the oxidation treatments and for the existence of vacant tetrahedral sites in micas. The main conclusions reached were (1) oxidation of structural Fe(II) in trioctahedral micas does not occur in aqueous solutions without an associated expansion or exfoliation of the interlayer region; (2) the charge created by oxidation is balanced by a combination of the deprotonation of structural hydroxyls, the ejection of octahedral cations (trivalent preferentially to divalent), and the loss of interlayer cations, and (3) the K-selectivity of the mica plays a key role in determining whether oxidation will occur in high-K solutions
Locomotive Biomechanics Wearing a Simulated Portable Life Support System During Varying Cognitive and Treadmill Grade Conditions
Background: The Portable Life Support System (PLSS) worn by astronauts during Extravehicular Activity (EVA) is contained within a backpack. Due to the inherent mass of the PLSS, astronaut center of mass (COM) is altered during ambulation. Recent studies from our laboratory suggest shifts in the COM of the PLSS have minimal effects on exercising metabolism, although differences were observed in trunk angles during ambulation. During EVA, astronauts continuously perform cognitive tasks (CG). Due to the distractive nature of these tasks, safety may be compromised by altered biomechanics. Purpose: To quantify lower extremity kinematics while walking with a simulated PLSS at variable inclines with and without a cognitive task. Methods: Nine subjects underwent treadmill gait analysis walking at 4.0 mph with a flat grade and a 6% decline wearing a 14.5 Kg. PLSS simulator. Within each treadmill grade condition, 30s of 3D motion capture data were collected as subjects walked while looking at a blank computer screen (CON), then while performing a CG. The CG consisted of identifying odd or even numbers and consonant or vowel letters presented for 0.1s on the computer screen. Kinematic data were obtained at 120 Hz using a motion capture system with a Helen Hayes marker set (Motion Analysis Software). Angle kinematic computations were completed using MatLab. Relevant measurements were compared within / between grade and cognitive conditions using a two-way factorial repeated measures analysis of variance test. Results: No significant differences were observed in scores on cognitive tests during the two grade conditions. Maximal left ankle plantarflexion was significantly greater in CG compared to CON; no other differences were observed between the CG and CON. There was a 2.5o difference in right knee flexion angle during the stance phase between the flat and decline positions (p \u3c 0.001). During the swing phase, grade affected knee flexion by 1.9o (p \u3c 0.002). Change in grade also resulted in differences in right and left hip extension in stance phase by 2.8o (p\u3c0.009) and 4.3o (p\u3c0.022) respectively. Conclusions: The cognitive task administered in this investigation is not adversely affected by ambulation at 4.0 mph regardless of treadmill grade. Furthermore, there were minimal effects on walking kinematics during the cognitive task. Subtle biomechanical differences were observed during the two grade conditions within both cognitive conditions. More research utilizing faster treadmill speeds and varying levels of CG may be necessary to detect possible alterations in biomechanics resulting from cognitive tasks
Synthesis of Colloidal Mn2+:ZnO Quantum Dots and High-TC Ferromagnetic Nanocrystalline Thin Films
We report the synthesis of colloidal Mn2+-doped ZnO (Mn2+:ZnO) quantum dots
and the preparation of room-temperature ferromagnetic nanocrystalline thin
films. Mn2+:ZnO nanocrystals were prepared by a hydrolysis and condensation
reaction in DMSO under atmospheric conditions. Synthesis was monitored by
electronic absorption and electron paramagnetic resonance (EPR) spectroscopies.
Zn(OAc)2 was found to strongly inhibit oxidation of Mn2+ by O2, allowing the
synthesis of Mn2+:ZnO to be performed aerobically. Mn2+ ions were removed from
the surfaces of as-prepared nanocrystals using dodecylamine to yield
high-quality internally doped Mn2+:ZnO colloids of nearly spherical shape and
uniform diameter (6.1 +/- 0.7 nm). Simulations of the highly resolved X- and
Q-band nanocrystal EPR spectra, combined with quantitative analysis of magnetic
susceptibilities, confirmed that the manganese is substitutionally incorporated
into the ZnO nanocrystals as Mn2+ with very homogeneous speciation, differing
from bulk Mn2+:ZnO only in the magnitude of D-strain. Robust ferromagnetism was
observed in spin-coated thin films of the nanocrystals, with 300 K saturation
moments as large as 1.35 Bohr magneton/Mn2+ and TC > 350 K. A distinct
ferromagnetic resonance signal was observed in the EPR spectra of the
ferromagnetic films. The occurrence of ferromagnetism in Mn2+:ZnO and its
dependence on synthetic variables are discussed in the context of these and
previous theoretical and experimental results.Comment: To be published in the Journal of the American Chemical Society Web
on July 14, 2004 (http://dx.doi.org/10.1021/ja048427j
Letter Report for Characterization of Biochar
On 27 November 2012, a bulk biochar sample was received for characterization of selected physical and chemical properties. The main purpose of the characterization was to help determine the degree to which biochar would be suitable as a soil amendment to aid in growth of plants. Towards this end, analyses to determine specific surface, pH, cation-exchange capacity, water retention, and wettability (i.e. surface tension) were conducted. A second objective was to determine how uniform these properties were in the sample. Towards this end, the sample was separated into fractions based on initial particle size and on whether the material was from the external surface or the internal portion of the particle. Based on the results, the biochar has significant liming potentials, significant cation-retention capacities, and highly variable plant-available moisture retention properties that, under the most favorable circumstances, could be helpful to plants. As a consequence, it would be quite suitable for addition to acidic soils and should enhance the fertility of those soils
Isokinetic Knee Strength is Associated with Knee Landing Kinematics during Double-leg Vertical and Depth Jumps
Muscular deficiencies, imbalances, or incorrect mechanics in jumping and landing may result in significant knee ligament strain and increased risk for injury in athletes. PURPOSE: This study aimed to identify possible associations between isokinetic knee flexion and extension strength and peak knee flexion and knee adduction landing angles during multiple jumping tasks. We hypothesized that males and females with greater quadriceps and hamstrings strength would land with greater peak knee flexion and less knee adduction. METHODS: After signing informed consent or adolescent assent forms approved by the committee for the protection of human subjects, eighteen participants (8 female; 10 male) volunteered for this project (24.4+8.7 y; 68.3+18.3 kg; 166.5+15.3 cm).The testing session began with anthropometric measurements of the subjects’ height, weight, and lean body mass. Following a standardized cycle warm-up, participants were outfitted with a lower-body marker set and 3D motion capture data were collected during two countermovement vertical jumps (CMVJ) and depth jumps from a small, 30-cm box (SBDJ) and large, 46-cm box (LBDJ). Isokinetic knee flexion-extension peak torques were then collected at 60˚/sec and 240˚/sec. Pearson correlation coefficients were computed between the peak flexion-extension torques at each angular velocity and peak right knee flexion and adduction landing angles. Alpha was set at a critical level of
Effects of Different Lifting Cadences on Ground Reaction Forces during the Squat Exercise
The purpose of this investigation was to determine the effect of different cadences on the ground reaction force (GRF(sub R)) during the squat exercise. It is known that squats performed with greater acceleration will produce greater inertial forces; however, it is not well understood how different squat cadences affect GRF(sub R). It was hypothesized that faster squat cadences will result in greater peak GRF(sub R). METHODS: Six male subjects (30.8+/-4.4 y, 179.5+/-8.9 cm, 88.8+/-13.3 kg) with previous squat experience performed three sets of three squats using three different cadences (FC = 1 sec descent/1 sec ascent; MC = 3 sec descent/1 sec ascent; SC = 4 sec descent/2 sec ascent) with barbell mass equal to body mass. Ground reaction force was used to calculate inertial force trajectories of the body plus barbell (FI(sub system)). Forces were normalized to body mass. RESULTS: Peak GRF(sub R) and peak FI(sub system) were significantly higher in FC squats compared to MC (p=0.0002) and SC (p=0.0002). Range of GRF(sub R) and FI(sub system) were also significantly higher in FC compared to MC (p<0.05), and MC were significantly higher than SC (p<0.05). DISCUSSION: Faster squat cadences result in significantly greater peak GRF(sub R) due to the inertia of the system. GRF(sub R) was more dependent upon decent cadence than on ascent cadence. PRACTICAL APPLICATION: This study demonstrates that faster squat cadences produce greater ground reaction forces. Therefore, the use of faster squat cadences might enhance strength and power adaptations to long-term resistance exercise training. Key Words: velocity, weight training, resistive exercis
The Environment Transport of Radium and Plutonium: A Review By Brice Smith and Alexandra Amonette
In this report we will provide a brief review of the environmental transport of two specific radionuclides. In Chapter Two we will consider the mobility of radium. This naturally occurring radionuclide is part of the uranium and thorium decay series, and is thus a potential concern in many areas where these elements have been mined or processed. In addition to the large number of sites with radium bearing waste, we chose to focus on this radionuclide in part due to the high concentrations of radium-226, and its thorium-230 parent, in the raffinate waste from the former Fernald Feed Material Production Plant in Ohio. In Chapter Three we will discuss the mobility of plutonium, and to some extent other transuranic elements. Contamination with these anthropogenic radionuclides has been discovered at a number of DOE sites and, due to the long half lives of many of these elements, they are a potential concern for long-term management.
This research was completed money allocated during Round 5 of the Citizens’ Monitoring and Technical Assessment Fund (MTA Fund). Clark University was named conservator of these works.
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Preliminary Analysis of the Feasibility and Effectiveness of Whole Body Vibration as a Therapeutic Intervention in a Skilled Nursing Facility
Skeletal muscle sarcopenia results in loss of strength, power and functional capabilities leading to decreased independence and an increased reliance on the healthcare system. Exercise is an effective countermeasure to age related loss of muscle, but may be difficult in elderly patients with complex functional limitations. Whole body vibration (WBV) is a novel tool used to stimulate the neuromuscular system; research indicates it may improve strength, power, and balance in many populations. Purpose: The purposes of this study were to determine if WBV training is feasible in a skilled nursing facility and if standard of care (SOC) with augmented WBV training improves physical function in patients compared to SOC alone. Methods: A prospective cohort design was used to accomplish the study objectives. Twelve patients (10 females; 2 males) who were residents at a skilled nursing facility consented to the study protocol and were divided into two groups. Group 1 (CON; 73.8 ± 5.7 y; 165.0 ± 0.03 cm; 77.5 ± 11.6kg) underwent SOC therapy intervention including progressive balance, strength, and range of motion exercises. Group 2 (VIB; 74.1 ± 2.3y; 169.0 ± 0.04cm; 70.5 ± 4.3kg) underwent a similar physical therapy intervention but also completed progressive WBV treatment on a symmetrically vibrating plate (2mm; 25-35 Hz). Patients completed clinical tests of physical function before and after the 23 ± 2.3 day intervention. Physical function tests included timed up-and-go (TUG) tests from a 40cm chair and a Berg balance assessment (BBA). Additionally, manual muscle tests were completed using a hand-held dynamometer for hip flexion (HF), hip abduction (HA), knee extension (KE), knee flexion (KF), plantar flexion (PF), and dorsi-flexion (DF). Student’s t-tests were used to compare the difference scores pre- and post-intervention; alpha was set at p\u3c0.05 to determine statistical significance. Results: No adverse effects were documented in either group throughout the study. Mean physical function improved in all tested variables for both groups. However, no between group differences (CON vs. VIB) were observed in BBA (p=0.52), TUG (p=0.07), HF (p=0.80), HA (p=0.47), KE (p=0.73), KF (p=0.97), PF (p=0.59), and DF (p=0.83). Conclusions: Use of WBV as an adjunct exercise intervention in a skilled nursing facility was feasible and safe in this small sample. Although no between group differences were evident, a larger sample is needed to definitively accept or reject the hypothesis. Moreover, systematic research is needed to develop precise protocols to effectively and efficiently utilize WBV in hospitalized elders
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