164 research outputs found

    High performance forward swept wing aircraft

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    A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum

    Large-Scale Wind-Tunnel Tests and Evaluation of the Low-Speed Performance of a 35 deg Sweptback Wing Jet Transport Model Equipped with a Blowing Boundary-Layer-Control Flap and Leading-Edge Slat

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    A wind-tunnel investigation was conducted to determine the effect of trailing-edge flaps with blowing-type boundary-layer control and leading-edge slats on the low-speed performance of a large-scale jet transport model with four engines and a 35 deg. sweptback wing of aspect ratio 7. Two spanwise extents and several deflections of the trailing-edge flap were tested. Results were obtained with a normal leading-edge and with full-span leading-edge slats. Three-component longitudinal force and moment data and boundary-layer-control flow requirements are presented. The test results are analyzed in terms of possible improvements in low-speed performance. The effect on performance of the source of boundary-layer-control air flow is considered in the analysis

    Time-averaged aerodynamic loads on the vane sets of the 40- by 80-foot and 80- by 120-foot wind tunnel complex

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    Time-averaged aerodynamic loads are estimated for each of the vane sets in the National Full-Scale Aerodynamic Complex (NFAC). The methods used to compute global and local loads are presented. Experimental inputs used to calculate these loads are based primarily on data obtained from tests conducted in the NFAC 1/10-Scale Vane-Set Test Facility and from tests conducted in the NFAC 1/50-Scale Facility. For those vane sets located directly downstream of either the 40- by 80-ft test section or the 80- by 120-ft test section, aerodynamic loads caused by the impingement of model-generated wake vortices and model-generated jet and propeller wakes are also estimated

    Evaluation of fat-free mass by whole-body counter in Japanese healthy young adults

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    Whole-body counters (WBCs) are special instruments for measuring internal irradiation doses and are usually housed within or around nuclear facilities in the event of unexpected radiation emergencies. As a substantial proportion of total body potassium (TBK) is found in fat-free mass (FFM), FFM volume can be predicted from WBC-measured 40K. We screened TBK in Japanese healthy young adults using a WBC and found strong linear correlations between TBK and lean body mass (LBM) and body mass index (r = 0.97, P < 0.01 and r = 0.47, P < 0.01, respectively). Multiple linear regression analysis, following adjustments for sex, indicates that only LBM has a significant correlation with TBK (P < 0.01). These results strongly support the feasibility of using WBCs for estimating FF

    Caregiver burden mediates between caregiver\u27s mental health condition and elder\u27s behavioral problems among Japanese family caregivers

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    Objectives: In Japan, the prevalence of depression has been reported to occur among 1 in 4 family caregivers. The purpose of this study was to investigate the self-rated burden associated with mental health conditions among caregivers.Methods: We studied 95 caregivers aged 38-87 years in a cross-sectional study. The General Health Questionnaire (GHQ-12) score of 4 or more was defined as poor mental health.Results: The proportion of caregivers with poor mental health was 24%. Caregivers with a high GHQ-12 score had the number of caregiver burdens increased by 2.5-fold compared to those with a low GHQ-12 score (p = 0.001). The proportion of caregivers with a high GHQ-12 score was significantly higher with an increasing number of behavioral problems among care recipients (p = 0.003). A mediational model was used to identify the underlying mechanism of the relationship between the number of behavioral problems and poor mental health in caregivers. Consequently, we found that mental health conditions in caregivers were associated with both the number of caregiver burdens and behavioral problems among care recipients.Conclusions: It is vital to provide support not only to the caregivers but also to their elderly relatives, paying particular attention to early identification of poor mental health in caregivers so as to administer effective interventions, and to offer useful advice concerning how to deal with behavioral problems

    Estimation of Blood Loss in Total Knee Arthroplasty with and without Tourniquet

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    Total knee arthroplasty (TKA) without a tourniquet can reduce the risk of large venous emboli, but is associated with increased blood loss. To provide an accurate estimate of this blood loss, we divided 136 patients who underwent primary TKA into four groups based on the type of operation: 1) bilateral TKA with tourniquet; 2) bilateral TKA without tourniquet; 3) unilateral TKA with tourniquet; and 4) unilateral TKA without tourniquet. Blood loss was estimated by calculating the fall in hemoglobin and total blood volume corrected for Japanese. A small difference in intraoperative blood loss was seen between unilateral TKA without tourniquet (308 ml) and bilateral TKA without tourniquet (411 ml). Total blood loss was 879 ml in unilateral TKA with tourniquet, 1165 ml in unilateral TKA without tourniquet, 1458 ml in bilateral TKA with tourniquet and 1823 ml in bilateral TKA without tourniquet. Uni- and bilateral TKAs without a tourniquet were thus associated with an increased blood loss. Performing TKA without a tourniquet should thus be reconsidered to avoid venous thromboembolism

    Appendicular bone mass and knee and hand osteoarthritis in Japanese women: a cross-sectional study

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    BACKGROUND: It has been reported that there is an inverse association between osteoarthritis (OA) and osteoporosis. However, the relationship of bone mass to OA in a Japanese population whose rates of OA are different from Caucasians remains uncertain. METHODS: We studied the association of appendicular bone mineral density (second metacarpal; mBMD) and quantitative bone ultrasound (calcaneus; stiffness index) with knee and hand OA among 567 Japanese community-dwelling women. Knee and hand radiographs were scored for OA using Kellgren-Lawrence (K/L) scales. In addition, we evaluated the presence of osteophytes and of joint space narrowing. The hand joints were examined at the distal and proximal interphalangeal (DIP, PIP) and first metacarpophalangeal/carpometacarpal (MCP/CMC) joints. RESULTS: After adjusting for age and body mass index (BMI), stiffness index was significantly higher in women with K/L scale, grade 3 at CMC/MCP joint compared with those with no OA. Adjusted means of stiffness index and mBMD were significantly higher in women with definite osteophytes at the CMC/MCP joint compared to those without osteophytes, whereas there were no significant differences for knee, DIP and PIP joints. Stiffness index, but not mBMD, was higher in women with definite joint space narrowing at the CMC/MCP joint compared with those with no joint space narrowing. CONCLUSIONS: Appendicular bone mass was increased with OA at the CMC/MCP joint, especially among women with osteophytes. Our findings suggest that the association of peripheral bone mass with OA for knee, DIP or PIP may be less clearcut in Japanese women than in other populations

    Post-Traumatic Stress Disorder Among Senior Victims of Tsunami-Affected Areas in Southern Sri Lanka

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    Background: On 26 December 2004, a large earthquake occurred off the coast of Sumatra, and a devastating tsunami struck surrounding countries. Sri Lanka was seriously affected, with more than 31,000 deaths and 4,000 people missing. Objective: To elucidate the relationship between factors of tsunami-related exposure and mental health conditions among the senior residents of tsunami-affected areas in southern Sri Lanka. Subjects: A total of 90 subjects (43 men, 47 women) aged 60 years or older who were living in the Matara district at the time of the tsunami attack. Methods: A survey by interview using a structured questionnaire was conducted in 2008. The collected information included demographic factors, tsunami-related exposure and mental health conditions. The Impact of Event Scale-Revised (IES-R) was used to assess their post-traumatic stress disorder symptoms. Results: The median of the IES-R score was significantly higher in those who were situated at home; those who saw anyone the dead or injured; those whose evacuations were delayed; those whose family member or friend was injured; those who were injured; those who lost their children, spouse or family members; those whose family member was missing; those who lost livelihood, compared with those who were not or those who did not. Multiple linear regression analysis showed that younger age and loss of or injury to family members due to the tsunami were significantly associated with an increase in IES-R score. Conclusion: The results indicate that tsunami-related exposures have affected elderly survivors\u27 mental health
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