2,087 research outputs found
The Total In-Flight Simulator (TIFS) aerodynamics and systems: Description and analysis
The aerodynamics, control system, instrumentation complement and recording system of the USAF Total In/Flight Simulator (TIFS) airplane are described. A control system that would allow the ailerons to be operated collectively, as well as, differentially to entrance the ability of the vehicle to perform the dual function of maneuver load control and gust alleviation is emphasized. Mathematical prediction of the rigid body and the flexible equations of longitudinal motion using the level 2.01 FLEXSTAB program are included along with a definition of the vehicle geometry, the mass and stiffness distribution, the calculated mode frequencies and mode shapes, and the resulting aerodynamic equations of motion of the flexible vehicle. A complete description of the control and instrumentation system of the aircraft is presented, including analysis, ground test and flight data comparisons of the performance and bandwidth of the aerodynamic surface servos. Proposed modification for improved performance of the servos are also presented
A study for active control research and validation using the Total In-Flight Simulator (TIFS) aircraft
The results of a feasibility study and preliminary design for active control research and validation using the Total In-Flight Simulator (TIFS) aircraft are documented. Active control functions which can be demonstrated on the TIFS aircraft and the cost of preparing, equipping, and operating the TIFS aircraft for active control technology development are determined. It is shown that the TIFS aircraft is as a suitable test bed for inflight research and validation of many ACT concepts
Normal Values of Circulating IGF-I Bioactivity in the Healthy Population: Comparison with five widely used IGF-I immunoassays
Background: IGF-I immunoassays are primarily used to estimate IGF-I bioactivity. Recently, an IGFI
specific Kinase Receptor Activation Assay (KIRA) has been developed as an alternative method.
However, no normative values have been established for the IGF-I KIRA.
Objective: To establish normative values for the IGF-I KIRA in healthy adults.
Design: Cross-sectional study in healthy non-fasting blood donors.
Study participants: 426 healthy individuals (310 M, 116 F; age range: 18 – 79 yrs)
Main outcome Measures: IGF-I bioactivity determined by the KIRA. Results were compared with
total IGF-I, measured by five different IGF-I immunoassays.
Results: Mean (± SD) IGF-I bioactivity was 423 (± 131) pmol/L and decreased with age (β = -3.4
pmol/L/yr, p < 0.001). In subjects younger than 55 yrs mean IGF-I bioactivity was significantly higher
in women than in men. Above this age this relationship was inverse, suggesting a drop in IGF-I
bioactivity after menopause. This drop was not reflected in total IGF-I levels. IGF-I bioactivity was
significantly related to total IGF-I (rs varied between 0.46 – 0.52; P-values < 0.001).
Conclusions: We established age-specific normative values for the IGF-I KIRA. We observed a
significant drop in IGF-I bioactivity in women between 50 and 60 years, which was not perceived by
IGF-I immunoassays. The IGF-I KIRA, when compared to IGF-I immunoassays, theoretically has the
advantage that it measures net effects of IGF-binding proteins on IGF-I receptor activation. However,
it has to be proven whether information obtained by the IGF-I KIRA is clinically more relevant than
measurements obtained by IGF-I immunoassays
Diagnostische Bedeutung der Proteinbindung von Plasmacortisol, bestimmt durch Dextrangelfiltration
1. Mittels Dextrangelfiltration wurde nach Inkubation von markiertem Cortisol und Plasma der proteingebundene und der sog. freie Anteil (%) des endogenen Plasmacortisols ermittelt und bei gleichzeitiger fluorimetrischer Bestimmung der 11-OHCS auch die Menge proteingebundenen, bzw. sog. freien Cortisols (µg-%) berechnet.
2. Die diagnostische Brauchbarkeit der Methode wurde bei Patienten mit Nebennierenrindeninsuffizienz, mit Hypophysentumoren, nach Hypophysektomie, mit Cushing-Syndrom mit der fluorimetrischen Bestimmung der 11-OHCS verglichen. Die einfache Bestimmung der Cortisolbindung war bei hypophysektomierten Patienten der Bestimmung der 11-OHCS überlegen und entsprach der aufwendigeren ACTH-Belastung.
3. Falsch hohe fluorimetrische 11-OHCS-Spiegel im Plasma unter Spirolacton- oder Oestrogenbehandlung und in der Gravidität lassen sich durch Bestimmung der Cortisolbindung klären. Bei Schilddrüsenüberfunktion war das sog. freie Cortisol im Plasma relativ und absolut vermehrt, bei Schilddrüsenunterfunktion fand sich eine Zunahme des plasmaproteingebundenen Cortisols.1. Following incubation of labeled cortisol and plasma the percentages of protein bound and socalled free endogenous cortisol were determined by means of dextran gel filtration.
2. The diagnostic value of this method was compared with fluorimetric determinations of 11-OHCS for patients with adrenal insufficiency, Cushing-Syndrome, pituitary tumors and after hypophysectomy. In hypophysectomized patients the simple determination of protein bound cortisol was found to correlate well with diagnostic ACTH-infusion tests and to be more sensitive than fluorimetric determinations of 11-OHCS in 9 a.m. plasma.
3. Falsely elevated fluorimetric values of plasma 11-OHCS in patients treated with spirolactone or estrogens, resp. during pregnancy may be recognized through determination of cortisol binding. — In thyrotoxicosis socalled free cortisol was elevated, both relatively and absolutely; in hypothyroidism an increase of protein bound cortisol was found
The impact of growth promoters on muscle growth and the potential consequences for meat quality
To meet the demands of increased global meat consumption, animal production systems will have to become more efficient, or at least maintain the current efficiency utilizing feed ingredients that are not also used for human consumption. Use of growth promoters is a potential option for increasing production animal feed efficiency and increased muscle growth. The objective of this manuscript is to describe the mechanisms by which the growth promoters, beta-adrenergic agonists and growth hormone, mediate their effects, with specific consideration of the aspects which have implications for meat quality.The work described in this manuscript was supported by a BBSRC LINK Zoetis grant, number BB/J005320/1, as well as a BBSRC CASE PhD studentship awarded to David Brown and Krystal Hemmings and a PhD scholarship awarded to Molebeledi HD Mareko by the Botswana College of Agricultur
Identification of social problems in Neighborhood Four, Cambridge
Massachusetts Institute of Technology. Dept. of City and Regional Planning. Thesis. 1967. M.C.P.Includes bibliographical references (leaves 128-129).by Pamela Daughaday Emerson.M.C.P
Severe paraneoplastic hypoglycemia in a patient with a gastrointestinal stromal tumor with an exon 9 mutation: a case report
BACKGROUND: Non-islet cell tumor induced hypoglycemia (NICTH) is a very rare phenomenon, but even more so in gastrointestinal stromal tumors. It tends to present in large or metastatic tumors, and can appear at any time in the progression of the disease. We present herein a case of NICTH in a GIST tumor and report an exon 9 mutation associated to it. CASE PRESENTATION: A thirty nine year-old man with a recurrent, metastatic gastrointestinal stromal tumor presented to the hospital with nausea, dizziness, loss of consciousness, and profound hypoglycemia (20 mg/dL). There was no evidence of factitious hypoglycemia. He was stabilized with a continuous glucose infusion and following selective vascular embolization, the patient underwent debulking of a multicentric 40 cm × 25 cm × 10 cm gastrointestinal stromal tumor. After resection, the patient became euglycemic and returned to his normal activities. Tumor analysis confirmed excessive production of insulin-like growth factor II m-RNA and the precursor protein, "big" insulin-like growth factor II. Mutational analysis also identified a rare, 6 bp tandem repeat insert (gcctat) at position 1530 in exon 9 of KIT. CONCLUSION: Optimal management of gastrointestinal stromal tumor-induced hypoglycemia requires a multidisciplinary approach, and surgical debulking is the treatment of choice to obtain immediate symptom relief. Imatinib or combinations of glucocorticoids and growth hormone are alternative palliative strategies for symptomatic hypoglycemia. In addition, mutations in exon 9 of the tyrosine kinase receptor KIT occur in 11–20% of GIST and are often associated with poor patient outcomes. The association of this KIT mutation with non-islet cell tumor induced hypoglycemia has yet to be established
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