4,974 research outputs found
A 10,000-hr life test of an engineering model resistojet
One of the major issues associated with using resistojet thrusters on Space Station Freedom is the long life required. An engineering model resistojet was life-tested to determine if it was capable of meeting that requirement. This thruster, which was designed for 10,000 hr of operation at 2552.4 F (1400 C) or less under cyclical thermal conditions, successfully operated for 10,036 hr at 1836 F (1002 C) while undergoing 141 thermal cycles
Melody based tune retrieval over the World Wide Web
In this paper we describe the steps taken to develop a Web-based version of an existing stand-alone, single-user digital library application for melodical searching of a collection of music. For the three key components: input, searching, and output, we assess the suitability of various Web-based strategies that deal with the now distributed software architecture and explain the decisions we made. The resulting melody indexing service, known as MELDEX, has been in operation for one year, and the feed-back we have received has been favorable
Spiritual Well-Being Scale: Mental and Physical Health Relationships (Chapter 48 of Oxford Textbook of Spirituality in Healthcare)
The existence of this handbook documents the recent increase in research on and practical attention to the role of spirituality in healthcare. One essential companion to the concept of spirituality is spiritual well-being (SWB).[1] That is, although the degree and type of spirituality per se can no doubt play an important role in how well a person faces the dilemmas related to health issues,[2,3] the degree to which a person perceives or derives a sense of wellbeing from that spirituality may be equally or more important. In this connection, SWB is an outcome indicator, or barometer, of how well a person is doing in the face of whatever the person is confronting.[4] Therefore, although SWB is not synonymous with spirituality, it is closely related to it. Similarly, SWB is not synonymous with mental health or physical health, but is likely to be related to both of them. SWB connotes one\u27s subjective perception of well-being in both the religious and/or existential dimensions in accord with whatever is implicitly or explicitly conceived of as a spiritual umbrella for the individual. The Spiritual Well-Being Scale (SWBS)* was developed in order to be a tool for self-assessment of these aspects of general perceived well-being. [ 4,5]
Since its first publication in 1982, a large body of research has been done with the SWBS. In preparation for writing this chapter, a literature search documented the scale\u27s use in over 300 published articles and chapters, 190 doctoral dissertations and Masters theses, 35 posters and presentations, and 50 unpublished papers. It has also been reprinted in no less than 4 books on palliative care and counseling. [ 6-9] An exhaustive review of all of this research is beyond the scope of this chapter; the interested reader is referred to a companion review article. [ 10] Here, we focus specifically and selectively on research related to healthcare. We highlight those studies using the SWBS that are related to mental health variables or to the mental and well-being issues that are consequences or correlates of physical health conditions.
In order to maximize the usefulness of this chapter, it is necessary to ( 1) summarize the intellectual roots of the concept of SWB and what the SWBS does and does not measure, (2) explain the meaning and utility of its religious well-being (RWB) and existential well-being (EWB) subscales, (3) summarize the literature with the SWBS as related to mental and physical health variables, ( 4) note any strengths and weaknesses, research directions, and applications of the SWBS, and (5) summarize implications of SWB research for healthy health care practice
High Redshift Candidates and the Nature of Small Galaxies in the Hubble Deep Field
We present results on two related topics: 1. A discussion of high redshift
candidates (z>4.5), and 2. A study of very small galaxies at intermediate
redshifts, both sets being detected in the region of the northern Hubble Deep
Field covered by deep NICMOS observations at 1.6 and 1.1 microns. The high
redshift candidates are just those with redshift z>4.5 as given in the recent
catalog of Thompson, Weymann and Storrie-Lombardi, while the ``small galaxy''
sample is defined to be those objects with isophotal area <= 0.2 squ. arcsec
and with photometric redshifts 1<z<4.5. Of the 19 possible high redshift
candidates listed in the Thompson et al. catalog, 11 have (nominal) photometric
redshifts less than 5.0. Of these, however, only 4 are ``robust'' in the sense
of yielding high redshifts when the fluxes are randomly perturbed with errors
comparable to the estimated measuring error in each wave band. For the 8 other
objects with nominal photometric redshifts greater than 5.0, one (WFPC2 4--473)
has a published spectroscopic redshift. Of the remaining 7, 4 are robust in the
sense indicated above. Two of these form a close pair (NIC 586 and NIC 107).
The redshift of the object having formally the highest redshift, at 6.56
(NIC118 = WFPC2 4--601), is problematic, since F606W and F814W flux are clearly
present, and the nature of this object poses a dilemma. (abridged)Comment: 44 pages, 12 figures, to appear in ApJ v591, July 10, 200
Normalised Root Mean Square and Amplitude of Sidebands of Vibration Response as Tools for Gearbox Diagnosis
Quick assessment of the condition of gearboxes used in helicopters is a safety requirement. One of the most widely used helicopter on-board-mounted condition monitoring system these days is the Health and Usage Monitoring System. It has been specifically designed to monitor the condition of all safety-critical components operating in the helicopter through calculation of so-called condition indicators (CIs) - signal processing routines designed to output a single number that represents the condition of the monitored component. Among number of available parameters, there is a couple of CIs that over the years of testing have earned a reputation of being the most reliable measures of the gear tooth condition. At the same time, however, it has been observed that in some cases, those techniques do not properly indicate the deteriorating condition with the propagation of a gear tooth fault with the period of operation. Hence, three more robust methods have been suggested, which are discussed in this article
Constraining cosmologies with fundamental constants I. Quintessence and K-Essence
Many cosmological models invoke rolling scalar fields to account for the
observed acceleration of the expansion of the universe. These theories
generally include a potential V(phi) which is a function of the scalar field
phi. Although V(phi) can be represented by a very diverse set of functions,
recent work has shown the under some conditions, such as the slow roll
conditions, the equation of state parameter w is either independent of the form
of V(phi) or is part of family of solutions with only a few parameters. In
realistic models of this type the scalar field couples to other sectors of the
model leading to possibly observable changes in the fundamental constants such
as the fine structure constant alpha and the proton to electron mass ratio mu.
This paper explores the limits this puts on the validity of various cosmologies
that invoke rolling scalar fields. We find that the limit on the variation of
mu puts significant constraints on the product of a cosmological parameter w+1
times a new physics parameter zeta_mu^2, the coupling constant between mu and
the rolling scalar field. Even when the cosmologies are restricted to very slow
roll conditions either the value of zeta_mu must be at the lower end of or less
than its expected values or the value of w+1 must be restricted to values
vanishingly close to 0. This implies that either the rolling scalar field is
very weakly coupled with the electromagnetic field, small zeta_mu, very weakly
coupled with gravity, w+1 ~ 0 or both. These results stress that adherence to
the measured invariance in mu is a very significant test of the validity of any
proposed cosmology and any new physics it requires. The limits on the variation
of mu also produces a significant tension with the reported changes in the
value of alpha.Comment: Accepted for publication in MNRAS 10 pages, 6 figure
Relativistic microburst storm characteristics: Combined satellite and ground-based observations
We report a comparison of Solar Anomalous Magnetospheric Particle Explorer detected relativistic electron microbursts and short-lived subionospheric VLF perturbations termed FAST events, observed at Sodankyl Geophysical Observatory, Finland, during 2005. We show that only strong geomagnetic disturbances can produce FAST events, which is consistent with the strong link between storms and relativistic microbursts. Further, the observed FAST event perturbation decay times were consistent with ionospheric recovery from bursts of relativistic electron precipitation. However, the one-to-one correlation in time between microbursts and FAST events was found to be very low (similar to 1%). We interpret this as confirmation that microbursts have small ionospheric footprints and estimate the individual precipitation events to be <4 km radius. In contrast, our study strongly suggests that the region over which microbursts occur during storm event periods can be at least similar to 90 degrees in longitude (similar to 6 h in magnetic local time). This confirms earlier estimates of microburst storm size, suggesting that microbursts could be a significant loss mechanism for radiation belt relativistic electrons during geomagnetic storms. Although microbursts are observed at a much higher rate than FAST events, the ground-based FAST event data can provide additional insight into the conditions required for microburst generation and the time variation of relativistic precipitation
Clergy work-related psychological health : listening to the Ministers of Word and Sacrament within the United Reformed Church in England
Drawing on the classic model of balanced affect proposed by Bradburn (The structure of psychological well-being, Aldine, Chicago, IL, 1969), this study conceptualised poor work-related psychological health in terms of high levels of negative affect in the absence of acceptable levels of positive affect. In order to illuminate self-perceptions of work-related psychological health among a well-defined group of clergy, a random sample of 58 ministers of word and sacrament serving within the west midlands synod of the United Reformed Church in England completed an open-ended questionnaire concerned with the following six guiding questions. Do you enjoy your work? How would you define stress? How would you define burnout? What stresses are there in your ministry? What do you do to keep healthy? What can the church do to enhance the work-related psychological health of ministers? Content analysis highlighted the main themes recurring through these open-ended responses. The conclusion is drawn that ministers of word and sacrament within the United Reformed Church in England are exposed to a number of recurrent recognisable sources of stress. Suggestions are advanced regarding the need for future more detailed research and for the development of more effective pastoral strategies
Expand+Functional selection and systematic analysis of intronic splicing elements identify active sequence motifs and associated splicing factors
Despite the critical role of pre-mRNA splicing in generating proteomic diversity and regulating gene expression, the sequence composition and function of intronic splicing regulatory elements (ISREs) have not been well elucidated. Here, we employed a high-throughput in vivo Screening PLatform for Intronic Control Elements (SPLICE) to identify 125 unique ISRE sequences from a random nucleotide library in human cells. Bioinformatic analyses reveal consensus motifs that resemble splicing regulatory elements and binding sites for characterized splicing factors and that are enriched in the introns of naturally occurring spliced genes, supporting their biological relevance. In vivo characterization, including an RNAi silencing study, demonstrate that ISRE sequences can exhibit combinatorial regulatory activity and that multiple trans-acting factors are involved in the regulatory effect of a single ISRE. Our work provides an initial examination into the sequence characteristics and function of ISREs, providing an important contribution to the splicing code
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