547 research outputs found

    Helicopter simulator standards

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    The initial advisory circular was produced in 1984 (AC 120-XX). It was not finalized, however, because the FAR's for pilot certification did not recognize helicopter simulators and, therefore, permitted no credit for their use. That is being rectified, and, when the new rules are published, standards must be available for qualifying simulators. Because of the lack of a data base to support specification of these standards, the FAA must rely on the knowledge of experts in the simulator/training industry. A major aim of this workshop is to form a working group of these experts to produce a set of standards for helicopter training simulators

    Macroeconomic Implications of Alternative Exchange Rate Models

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    In this paper we estimate and compare several alternative exchange rate models that have received wide attention, but little comparison, during the 1970s. In order to compare purchasing power parity (PPP), nominal interest rate parity, real interest rate parity, and portfolio balance models, we first strip each down to its essential core and undertake comparable single-equation tests of both 'hard' and 'easy' (more and less constrained) versions of each model. We then embed each of the 'hard' versions in a new macroeconomic model of Canada, and assess their implications for the impacts of monetary and fiscal shocks. Using annual Canadian data from the 1950s and 1970s, all of the models have single-equation errors of about 3%, except for the 'hard' versions of PPP and real interest parity, which are heavily rejected by the data. In a macroeconomic context, the models have modestly different implications for the effects of fiscal shocks, and diverge more widely under monetary shocks.

    Penggunaan Abu Batu Bara Pltu Mpanau sebagai Bahan Stabilisasi Tanah Lempung

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    Penelitian ini bertujuan memeriksa pengaruh stabilisasi tanah lempung menggunakan bahanstabilisasi Abu batu bara dan semen. Abu batu bara yang digunakan adalah abu bara hasilpembakaran dari PLTU Mpanau Kecamatan Tawaeli Kota Palu yang lolos saringan No.200, tanahlempung yang diuji memiliki indeks plastisitas lebih besar dari 20. Sifat yang diperiksa adalah:Perubahan batas cair, kepadatan maksimum dan nilai CBR. Proporsi rancangan campuran terdiridari abu batu bara adalah 10% dan 20% semen sebesar 4% dan 8% masing-masing terhadapberat kering tanah lempung,.Hasil penelitian menunjukkan bahwa campuran abu batu bara dansemen mampu menurunkan nilai indeks plastisitas tanah lempung dari 27,33% menjadi 10,37 %,meningkatkan nilai CBR tanah dari 4,46% menjadi 13,8% untuk CBR rendaman dan dari 5,6%menjadi 15,5% untuk CBR tanpa rendama

    Expression of the neuroprotective slow Wallerian degeneration (WldS) gene in non-neuronal tissues

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    <p>Abstract</p> <p>Background</p> <p>The slow Wallerian Degeneration (<it>Wld</it><sup><it>S</it></sup>) gene specifically protects axonal and synaptic compartments of neurons from a wide variety of degeneration-inducing stimuli, including; traumatic injury, Parkinson's disease, demyelinating neuropathies, some forms of motor neuron disease and global cerebral ischemia. The <it>Wld</it><sup><it>S </it></sup>gene encodes a novel Ube4b-Nmnat1 chimeric protein (Wld<sup>S </sup>protein) that is responsible for conferring the neuroprotective phenotype. How the chimeric Wld<sup>S </sup>protein confers neuroprotection remains controversial, but several studies have shown that expression in neurons <it>in vivo </it>and <it>in vitro </it>modifies key cellular pathways, including; NAD biosynthesis, ubiquitination, the mitochondrial proteome, cell cycle status and cell stress. Whether similar changes are induced in non-neuronal tissue and organs at a basal level <it>in vivo </it>remains to be determined. This may be of particular importance for the development and application of neuroprotective therapeutic strategies based around <it>Wld</it><sup><it>S</it></sup>-mediated pathways designed for use in human patients.</p> <p>Results</p> <p>We have undertaken a detailed analysis of non-neuronal <it>Wld</it><sup><it>S </it></sup>expression in <it>Wld</it><sup><it>S </it></sup>mice, alongside gravimetric and histological analyses, to examine the influence of <it>Wld</it><sup><it>S </it></sup>expression in non-neuronal tissues. We show that expression of <it>Wld</it><sup><it>S </it></sup>RNA and protein are not restricted to neuronal tissue, but that the relative RNA and protein expression levels rarely correlate in these non-neuronal tissues. We show that <it>Wld</it><sup><it>S </it></sup>mice have normal body weight and growth characteristics as well as gravimetrically and histologically normal organs, regardless of Wld<sup>S </sup>protein levels. Finally, we demonstrate that previously reported <it>Wld</it><sup><it>S</it></sup>-induced changes in cell cycle and cell stress status are neuronal-specific, not recapitulated in non-neuronal tissues at a basal level.</p> <p>Conclusions</p> <p>We conclude that expression of Wld<sup>S </sup>protein has no adverse effects on non-neuronal tissue at a basal level <it>in vivo</it>, supporting the possibility of its safe use in future therapeutic strategies targeting axonal and/or synaptic compartments in patients with neurodegenerative disease. Future experiments determining whether Wld<sup>S </sup>protein can modify responses to injury in non-neuronal tissue are now required.</p

    Acuity and Contrast Sensitivity in Monkeys After Neonatal Intraocular Lens Implantation With and Without Parttime Occlusion of the Fellow Eye

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    Purpose. The authors used a monkey model to evaluate intraocular lenses (IOLs) for the treatment of infantile cataract in humans. Specifically, they sought to assess the effectiveness of IOLs, with and without occlusion therapy, in preventing amblyopia. Methods. A diffuser contact lens was placed on one eye each of 11 neonatal monkeys to simulate an infantile cataract. A unilateral lensectomy, combined with the implantation of an IOL, was performed on the same eye 1 to 2 weeks after birth. Clear contact lenses were used to adjust the optical correction of the pseudophakic eyes to a near point, and opaque lenses were used to maintain daily parttime (70%) occlusion of the fellow eyes of half the subjects. Behavioral methods were used to assess grating acuity, optotype acuity (Landolt C), and contrast sensitivity. Results. In five of the animals, complications that developed in the eye with the implant were severe enough to interfere with visual function. The authors present only behavioral outcomes obtained before or in the absence of surgical complications. In monkeys that underwent daily 70% occlusion, grating acuity in the pseudophakic eyes eventually matured to normal adult levels. Grating acuity was significantly poorer in animals with no occlusion therapy. Even in animals with normal grating acuity, assessments of optotype acuity revealed amblyopic deficits; contrast sensitivity was impaired as well at middle and low spatial frequencies. Conclusions. The current study demonstrates that if there are no complications secondary to surgery, normal grating acuity can be obtained in neonatal monkey eyes that undergo IOL implantation, optical correction of the pseudophakic eye to a near point, and 70% occlusion of the fellow eye. However, these good outcomes for grating acuity cannot be attained without occlusion therapy. In addition, optotype acuity and sensitivity to contrast always are impaired

    Clinical response to antibiotic regimens in lower limb cellulitis: a systematic review

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    There is variation in the treatment of lower limb cellulitis (LLC) with no agreement on the most effective antibiotic regimen. Many patients with cellulitis fail to respond to first-line antibiotics. This can negatively affect patient care and result in unnecessary hospital admissions. The aim of this systematic review was to determine the clinical response and safety of antibiotic regimens for the management of LLC. A systematic review for randomized controlled trials (RCTs) was conducted using OVID MEDLINE, Ovid Embase and Cochrane Central Register of Controlled Trials in January 2019. Outcomes of interest included the clinical response to antibiotic regimens (type, dose, route, duration) and the safety of antibiotics in LLC. Trial quality was identified using the Cochrane Risk of Bias tool. Four RCTs were included. All included studies showed no significant differences between the clinical response to different antibiotic type, administration route, treatment duration or dose. LLC may be overtreated and shorter courses of oral antibiotics, possibly with lower doses, may be more suitable. There is a lack of published data on the clinical response and safety of antibiotics in LLC. Three studies were high risk for bias overall. Further high-quality studies may help determine whether less intensive antibiotic regimens can effectively treat LLC

    Expression of a Low-Temperature-Induced Protein in Brassica napus

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    What Therapists Learn from Psychotherapy Clients: Effects on Personal and Professional Lives

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    While considerable research has examined how clients learn from psychotherapists, there is only sparse literature on what therapists learn from their therapy clients. In a qualitative, exploratory study, nine researchers interviewed 61 psychologists from across North America in order to see what psychotherapists may have learned and how they have been affected by their clients both personally and professionally. Participants responded to nine open-ended questions on learning about life-lessons, relationships, ethical decision-making, coping, courage, wisdom, psychopathology, personality, cultural differences, lifespan development and more. Participants’ richly elaborated responses were coded thematically and narrative data illustrates the most frequent themes. Therapists reported learning a great deal across each of the questions, consistently expressing respect for their clients\u27 resilience, courage and moral sensibilities
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