A practical approach to helicopter internal noise prediction

A practical and well correlated procedure for predicting helicopter internal noise is presented. It accounts for the propagation of noise along multiple paths on an octave by octave basis. The method is sufficiently general to be applicable to conventional helicopters as well as other aircraft types, when the appropriate structural geometry, noise source strengths, and material acoustic properties are defined. A guide is provided for the prediction of various helicopter noise sources over a wide range of horsepower for use when measured data are not available. The method is applied to the prediction of the interior levels of the Civil Helicopter Research Aircraft (CHRA), both with and without soundproofing installed. Results include good correlation with measured levels and prediction of the speech interference level within 1.5 db at all conditions. A sample problem is also shown illustrating the use of the procedure. This example calculates the engine casing noise observed in the passenger cabin of the CHRA

Effectiveness of Adult Rehabilitative Mental Health Services in Mental Health Recovery

Adult Rehabilitative Mental Health Services (ARMHS) is a Minnesota based psychiatric rehabilitation program for adults whose ability to function in daily life has been impaired due to the symptoms of mental illness. The goals set and actual outcomes achieved by clients during participation in ARMHS were examined in a secondary data analysis using the CHIME recovery model (Connectedness, Hope, Identity, Meaning in life, and Empowerment) to determine the effectiveness of the program in assisting clients recover from mental illness. Outcomes described were largely mapped to the areas of Connectedness, Meaningful activity, and Empowerment, which may be related to the behavioral orientation of goal development. Overall, the majority of outcomes described successful achievement of goals, supporting ARMHS as an effective service for assisting in recovery from mental illness. Implications for this study are the continued need to use consumer driven measurement tools like CHIME to assess recovery from the perspective of the client rather than assessments driven by the medical model. The improvement of outcome evaluation forms to integrate more accurate ways of measuring the components of recovery would improve the type and quality of data collected during the reassessment process

Effectiveness of Adult Rehabilitative Mental Health Services in Mental Health Recovery

Adult Rehabilitative Mental Health Services (ARMHS) is a Minnesota based psychiatric rehabilitation program for adults whose ability to function in daily life has been impaired due to the symptoms of mental illness. The goals set and actual outcomes achieved by clients during participation in ARMHS were examined in a secondary data analysis using the CHIME recovery model (Connectedness, Hope, Identity, Meaning in life, and Empowerment) to determine the effectiveness of the program in assisting clients recover from mental illness. Outcomes described were largely mapped to the areas of Connectedness, Meaningful activity, and Empowerment, which may be related to the behavioral orientation of goal development. Overall, the majority of outcomes described successful achievement of goals, supporting ARMHS as an effective service for assisting in recovery from mental illness. Implications for this study are the continued need to use consumer driven measurement tools like CHIME to assess recovery from the perspective of the client rather than assessments driven by the medical model. The improvement of outcome evaluation forms to integrate more accurate ways of measuring the components of recovery would improve the type and quality of data collected during the reassessment process

Gating of L-type Ca2+ channels in embryonic chick ventricle cells: dependence on voltage, current and channel density

1. L-type calcium channels in embryonic chick heart ventricle have voltage-dependent, time-variant kinetics when they conduct inward currents carried by 20 mM-Ba2+. Depolarizing the membrane from -20 to 20 mV increases mean open time from 1.4 to 4.2 ms. Mean open time increases monotonically with voltage. The single-channel conductance, 18 +/- 2 pS, is approximately linear over this voltage range, and the extrapolated reversal potential is 38 +/- 5 mV. 2. In cell-attached patches with five or more L-type Ca2+ channels in the patch, the currents elicited by 500 ms depolarizing steps, from a -80 mV holding potential, inactivate rapidly and have large tail currents. In the same patch, currents from a -40 mV holding potential are smaller, inactivate more slowly, and have practically no tail currents. 3. In cell-attached patches containing one of two L-type Ca2+ channels, currents from -80 or -40 mV are virtually identical, and they are similar to the currents from multichannel patches held at -40 mV. 4. The voltage-dependent, time-variant kinetics of individual L-type Ca2+ channels are unaltered if the patch is removed from the cell and forms an inside-out configuration. In these experiments the internal membrane was bathed with an artificial, intracellular-like solution containing no phosphorylating enzymes or substrates. 5. Cells bathed in 20 mM-Ba2+ solutions and held at -80 mV have currents with an early phase that inactivates in tens of milliseconds, a late phase that inactivates in hundreds of milliseconds, and a large, slow tail current. Currents from -40 mV have only the late phase and practically no tails. However, if the maximum current is less than 0.1 pA pF-1, records from either -80 or -40 mV are virtually identical, and they are similar to currents from cells with higher channel density held at -40 mV. Furthermore, if cells are stimulated before full recovery from inactivation, the reduced current is accompanied by slower inactivation. 6. Whole-cell currents in 1.5 mM-Ca2+ solutions are entirely abolished by addition of 20 microM-nifedipine, and they are enhanced 2-3 times by addition of 30 microM-cyclic AMP and 3 mM-ATP to the whole-cell recording electrode. The whole-cell currents in 20 mM-Ba2+ solutions are also completely blocked by 20 microM-nifedipine, regardless of kinetics or holding potential. Thus, by definition, the cells we are studying contain only L-type channels

Effect of channel block on the spiking activity of excitable membranes in a stochastic Hodgkin-Huxley model

The influence of intrinsic channel noise on the spontaneous spiking activity of poisoned excitable membrane patches is studied by use of a stochastic generalization of the Hodgkin-Huxley model. Internal noise stemming from the stochastic dynamics of individual ion channels is known to affect the collective properties of the whole ion channel cluster. For example, there exists an optimal size of the membrane patch for which the internal noise alone causes a regular spontaneous generation of action potentials. In addition to varying the size of ion channel clusters, living organisms may adapt the densities of ion channels in order to optimally regulate the spontaneous spiking activity. The influence of channel block on the excitability of a membrane patch of certain size is twofold: First, a variation of ion channel densities primarily yields a change of the conductance level. Second, a down-regulation of working ion channels always increases the channel noise. While the former effect dominates in the case of sodium channel block resulting in a reduced spiking activity, the latter enhances the generation of spontaneous action potentials in the case of a tailored potassium channel blocking. Moreover, by blocking some portion of either potassium or sodium ion channels, it is possible to either increase or to decrease the regularity of the spike train.Comment: 10 pages, 3 figures, published 200

Noise suppression by noise

We have analyzed the interplay between an externally added noise and the intrinsic noise of systems that relax fast towards a stationary state, and found that increasing the intensity of the external noise can reduce the total noise of the system. We have established a general criterion for the appearance of this phenomenon and discussed two examples in detail.Comment: 4 pages, 4 figure

Dark Energy and Neutrino Mass Limits from Baryogenesis

In this brief report we consider couplings of the dark energy scalar, such as Quintessence to the neutrinos and discuss its implications in studies on the neutrino mass limits from Baryogenesis. During the evolution of the dark energy scalar, the neutrino masses vary, consequently the bounds on the neutrino masses we have here differ from those obtained before.Comment: 5 pages,3 figures. Version accepted for publication in Phys. Rev.

Exploring Pompeii: discovering hospitality through research synergy

Hospitality research continues to broaden through an ever-increasing dialogue and alignment with a greater number of academic disciplines. This paper demonstrates how an enhanced understanding of hospitality can be achieved through synergy between archaeology, the classics and sociology. It focuses on classical Roman life, in particular Pompeii, to illustrate the potential for research synergy and collaboration, to advance the debate on hospitality research and to encourage divergence in research approaches. It demonstrates evidence of commercial hospitality activities through the excavation hotels, bars and taverns, restaurants and fast food sites. The paper also provides an example of the benefits to be gained from multidisciplinary analysis of hospitality and tourism

Use of temperature to improve West Nile virus forecasts

Ecological and laboratory studies have demonstrated that temperature modulates West Nile virus (WNV) transmission dynamics and spillover infection to humans. Here we explore whether inclusion of temperature forcing in a model depicting WNV transmission improves WNV forecast accuracy relative to a baseline model depicting WNV transmission without temperature forcing. Both models are optimized using a data assimilation method and two observed data streams: mosquito infection rates and reported human WNV cases. Each coupled model-inference framework is then used to generate retrospective ensemble forecasts of WNV for 110 outbreak years from among 12 geographically diverse United States counties. The temperature-forced model improves forecast accuracy for much of the outbreak season. From the end of July until the beginning of October, a timespan during which 70% of human cases are reported, the temperature-forced model generated forecasts of the total number of human cases over the next 3 weeks, total number of human cases over the season, the week with the highest percentage of infectious mosquitoes, and the peak percentage of infectious mosquitoes that on average increased absolute forecast accuracy 5%, 10%, 12%, and 6%, respectively, over the non-temperature forced baseline model. These results indicate that use of temperature forcing improves WNV forecast accuracy and provide further evidence that temperature influences rates of WNV transmission. The findings provide a foundation for implementation of a statistically rigorous system for real-time forecast of seasonal WNV outbreaks and their use as a quantitative decision support tool for public health officials and mosquito control programs

Prominent Human Health Impacts from Several Marine Microbes: History, Ecology, and Public Health Implications

This paper overviews several examples of important public health impacts by marine microbes and directs readers to the extensive literature germane to these maladies. These examples include three types of dinoflagellates (Gambierdiscus spp., Karenia brevis, and Alexandrium fundyense), BMAA-producing cyanobacteria, and infectious microbes. The dinoflagellates are responsible for ciguatera fish poisoning, neurotoxic shellfish poisoning, and paralytic shellfish poisoning, respectively, that have plagued coastal populations over time. Research interest on the potential for marine cyanobacteria to contribute BMAA into human food supplies has been derived by BMAA's discovery in cycad seeds and subsequent implication as the putative cause of amyotrophic lateral sclerosis/parkinsonism dementia complex among the Chamorro people of Guam. Recent UPLC/MS analyses indicate that recent reports that BMAA is prolifically distributed among marine cyanobacteria at high concentrations may be due to analyte misidentification in the analytical protocols being applied for BMAA. Common infectious microbes (including enterovirus, norovirus, Salmonella, Campylobacter, Shigella, Staphylococcus aureus, Cryptosporidium, and Giardia) cause gastrointestinal and skin-related illness. These microbes can be introduced from external human and animal sources, or they can be indigenous to the marine environment