2,096 research outputs found

    Esthetic and Recreational Potential of Small Naturalistic Streams Near Urban Areas

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    The purpose of this study was to find a way to evaluate the esthetic and recreational potential of small streams and their watersheds. Research was limited to naturalistic streams with drainage areas under 100 square miles and located within 25 miles of a city. A methodology, based on some previous work of the U.S. Soil Conservation Service and the principles or concepts of terrain analysis, land use planning, value Judgment philosophy and the economics of outdoor recreation, was developed and applied in detail to two streams (Boone and Jessamine Creeks) near Lexington, Kentucky. Evaluations were made of the streams\u27 potential for camping (primitive, transient and group), fishing, picnicking, a trail system (hiking, horseback riding, bicycling and auto tour routes), esthetic enjoyment (sightseeing, nature walks and walking for pleasure) and the establishment of natural, scenic and historic areas, Limited applications were also made to two other watersheds and to selected recreation sites on Boone and Jessamine Creeks. Extensions of these case studies resulted in procedures for estimating: visitation to a developed site, future participation demand generated by an urban area and the proportion of that demand that would be satisfied at a specific site, and the economic benefits that would accrue if the sites were developed. Conclusions reached were: (1) Esthetic and recreational values can be identified, inventoried and used to evaluate a watershed\u27s development potential. (2) The methodology yielded fairly accurate evaluations for most of the recreational activities considered. (3) The case studies revealed that many small stream areas possess medium to high potential for camping, fishing, picnicking, trail system development and some forms of esthetic enjoyment. (4) Visitation estimates were judged to be only approximate due to lack of relevant data on similar existing recreation areas. Estimates of participation demand, acreage requirements and annual benefits were somewhat more reliable. Suggestions for further research include: (1) Additional applications of the evaluation methodology to streams in other Kentucky urban areas and in states having climatic, topographic and socio-economic conditions different from Kentucky\u27s and (2) A feasibility study of the use of a psychometrics approach to determine personal preferences about outdoor recreation and the preservation of natural areas

    Transoral Approach to Excision of Massive Dermoid Cysts in Pediatric Patients: A Case Series

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    Floor of mouth (FOM) dermoid cysts are a rare but clinically significant lesion of the head and neck. Classically, large cysts have been excised via a transcervical approach, although the limits of the transoral approach are expanding. The majority of FOM dermoid cysts present in the midline, but true lateral cysts have been reported. In this case series, we describe 3 pediatric patients who all underwent successful transoral excision of massive dermoid cysts, along with a literature review. Massive cystic lesions were identified on preoperative imaging. The dermoid cysts averaged 6 × 4.3 × 5 cm and were successfully removed via a transoral approach. Two were removed via a median ventral FOM incision and one via a lateral trans-sublingual approach to the FOM. When needed, the geniohyoid muscle was divided to gain access to the cyst. All cysts were removed intact, although partial, controlled decompression was performed to aid in dissection. There were no post-operative complications. FOM dermoid cysts are a rare but important cause of pediatric neck masses that present a challenging but satisfying surgical opportunity. The transoral approach is a viable option for massive dermoid cysts superior to the mylohyoid

    Advanced information processing system for advanced launch system: Avionics architecture synthesis

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    The Advanced Information Processing System (AIPS) is a fault-tolerant distributed computer system architecture that was developed to meet the real time computational needs of advanced aerospace vehicles. One such vehicle is the Advanced Launch System (ALS) being developed jointly by NASA and the Department of Defense to launch heavy payloads into low earth orbit at one tenth the cost (per pound of payload) of the current launch vehicles. An avionics architecture that utilizes the AIPS hardware and software building blocks was synthesized for ALS. The AIPS for ALS architecture synthesis process starting with the ALS mission requirements and ending with an analysis of the candidate ALS avionics architecture is described

    Error Compensation of Single-Qubit Gates in a Surface Electrode Ion Trap Using Composite Pulses

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    The fidelity of laser-driven quantum logic operations on trapped ion qubits tend to be lower than microwave-driven logic operations due to the difficulty of stabilizing the driving fields at the ion location. Through stabilization of the driving optical fields and use of composite pulse sequences, we demonstrate high fidelity single-qubit gates for the hyperfine qubit of a 171Yb+^{171}\text{Yb}^+ ion trapped in a microfabricated surface electrode ion trap. Gate error is characterized using a randomized benchmarking protocol, and an average error per randomized Clifford group gate of 3.6(3)×10−43.6(3)\times10^{-4} is measured. We also report experimental realization of palindromic pulse sequences that scale efficiently in sequence length

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    Haptoglobin Phenotype, Preeclampsia Risk and the Efficacy of Vitamin C and E Supplementation to Prevent Preeclampsia in a Racially Diverse Population

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    Haptoglobin's (Hp) antioxidant and pro-angiogenic properties differ between the 1-1, 2-1, and 2-2 phenotypes. Hp phenotype affects cardiovascular disease risk and treatment response to antioxidant vitamins in some non-pregnant populations. We previously demonstrated that preeclampsia risk was doubled in white Hp 2-1 women, compared to Hp 1-1 women. Our objectives were to determine whether we could reproduce this finding in a larger cohort, and to determine whether Hp phenotype influences lack of efficacy of antioxidant vitamins in preventing preeclampsia and serious complications of pregnancy-associated hypertension (PAH). This is a secondary analysis of a randomized controlled trial in which 10,154 low-risk women received daily vitamin C and E, or placebo, from 9-16 weeks gestation until delivery. Hp phenotype was determined in the study prediction cohort (n = 2,393) and a case-control cohort (703 cases, 1,406 controls). The primary outcome was severe PAH, or mild or severe PAH with elevated liver enzymes, elevated serum creatinine, thrombocytopenia, eclampsia, fetal growth restriction, medically indicated preterm birth or perinatal death. Preeclampsia was a secondary outcome. Odds ratios were estimated by logistic regression. Sampling weights were used to reduce bias from an overrepresentation of women with preeclampsia or the primary outcome. There was no relationship between Hp phenotype and the primary outcome or preeclampsia in Hispanic, white/other or black women. Vitamin supplementation did not reduce the risk of the primary outcome or preeclampsia in women of any phenotype. Supplementation increased preeclampsia risk (odds ratio 3.30; 95% confidence interval 1.61-6.82, p<0.01) in Hispanic Hp 2-2 women. Hp phenotype does not influence preeclampsia risk, or identify a subset of women who may benefit from vitamin C and E supplementation to prevent preeclampsia
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