6 research outputs found

    Geophysical framework of northern end of Gulf of California structural province

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    More than 3,000 gravity observations in the Northern Gulf province, including an underwater gravity survey of the Salton Sea, show the over-all trend of isogal contours to be northwest, parallel to the tectonic pattern dominated by the San Andreas fault system. Contours northeast of the trough trend east, probably reflecting Transverse Range structures in this area. A prominent and linear gradient of 5 mgal/km marks the Banning-Mission Creek fault in the Coachella Valley but dies out southeastward at about the same point the surface trace disappears. The San Jacinto fault zone is characterized by a series of maxima and minima that tend to confirm continuity of this fault zone to the Gulf of California. A 15-20 mgal maximum over the Obsidian Buttes suggests a large anomalous mass at depth, or may be related to contemporaneous metamorphism of the Tertiary sedimentary section that has recently been observed in nearby steam wells. The regional gravity gradient indicates a crustal thickening northwest from the Gulf of California; inferred crustal thicknesses are 32 km at the International Border and 40 km at San Gorgonio Pass. Ten seismic refraction profiles in the Imperial and Coachella Valleys indicate several throughgoing velocity zones, but we are unable to correlate these with known stratigraphic units. The maximum thickness of sediments in the trough appears to be about 6.4 km (21,000 ft) just south of the International Border, with basement becoming shallower both to the north and south. The Salton trough has many geophysical and structural similarities to the Dead Sea rift, but the markedly en echelon pattern of major faults in the Salton trough and Gulf of California appears unique. A particular problem is presented by their orientation, which would suggest left-lateral displacement across the zone rather than the right-lateral displacement that is known to characterize at least the northern end of the province

    Strategies for Gait Retraining in a Collegiate Runner with Transfemoral Amputation: A Case Report

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    # Background More than fifty percent of people with limb amputations participate in sports or physical activity following amputation. Athletes with limb amputations may face additional challenges including phantom limb pain (PLP), psychological barriers, prosthetic complications, and gait abnormalities. Prevalence of PLP in the general amputee population is estimated to be as high as 85%. Despite the high prevalence of PLP, there is little research regarding the use of gait training as a treatment for PLP among both the general amputee population and athletes. # Case Description A 20-year old female collegiate track and field athlete presented with phantom knee pain brought on with running. The athlete demonstrated deficits in core and hip strength as well as decreased single leg stability bilaterally. Running gait analysis revealed circumduction with the prosthesis for limb advancement and increased vaulting with push off on the sound (uninvolved) limb. Gait retraining strategies were implemented to address video analysis findings and create a more efficient running gait and address phantom limb pain symptoms. # Outcomes Rehabilitation and gait retraining strategies were effective in improving several clinical and functional outcomes in this case. Significant improvements were noted in PLP, running gait mechanics, and the patient’s psychological and functional status as measured with a standardized outcome tool, the Patient-Reported Outcomes Measurement Information System^®^ (PROMIS^®^). # Discussion Running gait training following amputation could be a crucial component of rehabilitation for athletes in an attempt to lessen pain while running, especially in those experiencing phantom limb pain (PLP). Utilization of a multidisciplinary team in the gait retraining process is recommended. There is a need for further research to determine the effects of running gait retraining for management of PLP in athletes with amputation. # Level of Evidence

    A Geophysical Study of the Salton Trough of Southern California

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    More than 2300 gravity observations were made in the northern end of the Salton trough, including an underwater gravity survey of the Salton Sea. 400 gravity observations by Kovach are used to extend the gravity map southward and 700 gravity observations from oil companies and Woollard are used for part of the regional control. A complete Bouguer anomaly map of the California portion of the Salton trough area shows that the general trend of the isogal contours is parallel to the over-all northwest trend of the tectonic pattern. The contours northeast of the Coachella Valley trend east parallel to the Transverse Range structure. The Coachella Valley and Borrego sink are associated with gravity lows, the Salton volcanic domes with a gravity maximum, and the Peninsular Ranges with a gravity minimum. The anomalous mass of the Salton volcanic domes is 6 to 7 km deep with a radius of 3.5 to 4.5 km based on the "half-width" interpretation of a sphere. Due to uncertainties arising from contemporaneous metamorphism of the sediments and the ambiguity in the regional gravity field a detailed interpretation was not attempted. All of the major fault zones are associated with small gravity lows. A series of these small lows southeast along the projected trace of the Banning-Mission Creek fault may indicate continuation of faulting toward Yuma, Arizona. The steep gravity gradient across this fault in the Coachella Valley can be explained by a steep contact between crystalline rock and sediments which exceed 4 km thickness in the Indio-Mecca area. Seismic refraction profiles were established at Thousand Palms, Truckhaven, Frink, and Westmorland. These give depths to basement of 4350, 5540, 7340, and 18,300 ft respectively. The Westmorland profile establishes the depth to basement near the center of the trough. Regional gravity studies indicate that much of the gravity low over the Peninsular Ranges can be explained by a thickening of the crust from 29 to 33 km. The Imperial Valley, with over 5.5 km of sediments, is anomalously associated with a broad gravity high. This is interpreted in terms of a thinning crust under the valley possibly to a depth of 21 km, relative to 29 km at San Diego. The crustal structure of the Imperial Valley is probably the northward continuation of the structure of the Gulf of California and may represent the initial stages of an alteration from continental to oceanic type section by rifting and northwest movement of the Baja California peninsula and western California relative to the stable area northeast of the San Andreas fault system.</p

    Review of Literature for Air Medical Evacuation High-Level Containment Transport

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    Introduction Aeromedical evacuation (AE) is a challenging process, further complicated when a patient has a highly hazardous communicable disease (HHCD). We conducted a review of the literature to evaluate the processes and procedures utilized for safe AE high-level containment transport (AE-HLCT) of patients with HHCDs. Methods A literature search was performed in PubMed/MEDLINE (from 1966 through January 2019). Authors screened abstracts for inclusion criteria and full articles were reviewed if the abstract was deemed to contain information related to the aim. Results Our search criteria yielded 14 publications and were separated based upon publication dates, with the natural break point being the beginning of the 2013-2016 Ebola virus disease epidemic. Best practices and recommendations from identified articles are subdivided into pre-flight preparations, inflight operations, and post-flight procedures. Conclusions Limited peer-reviewed literature exists on AE-HLCT, including important aspects related to healthcare worker fatigue, alertness, shift scheduling, and clinical care performance. This hinders the sharing of best practices to inform evacuations and equip teams for future outbreaks. Despite the successful use of different aircraft and technologies, the unique nature of the mission opens the opportunity for greater coordination and development of consensus standards for AE-HLCT operations
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