757 research outputs found
Impingement effect of service module reaction control system engine plumes. Results of service module reaction control system plume model force field application to an inflight Skylab mission proximity operation situation with the inflight Skylab response
Plume impingement effects of the service module reaction control system thruster firings were studied to determine if previous flight experience would support the current plume impingement model for the orbiter reaction control system engines. The orbiter reaction control system is used for rotational and translational maneuvers such as those required during rendezvous, braking, docking, and station keeping. Therefore, an understanding of the characteristics and effects of the plume force fields generated by the reaction control system thruster firings were examined to develop the procedures for orbiter/payload proximity operations
Apollo experience report: Flight anomaly resolution
The identification of flight anomalies, the determination of their causes, and the approaches taken for corrective action are described. Interrelationships of the broad range of disciplines involved with the complex systems and the team concept employed to ensure timely and accurate resolution of anomalies are discussed. The documentation techniques and the techniques for management of anomaly resolution are included. Examples of specific anomalies are presented in the original form of their progressive documentation. Flight anomaly resolution functioned as a part of the real-time mission support and postflight testing, and results were included in the postflight documentation
Beef production: potential and output in mid-Canterbury
Climate and pasture production in mid-Canterbury have
been discussed by Rickard (1968). Under âdrylandâ farming
conditions, pasture
of some 110 to 130 aBys when production is very low
reduction is-limited by (1) winters
and (2) dry periods of variable incidence and duration
during the remainder of the year. These latter not only
restrict output every year but also result in a large âbetween
years â variation in annual pasture production. However,
adequate irrigation eliminates the dry periods and
results in pasture production characterized by :
(1) A higher annual production of some 9,000 to 10,000
lb D.M. per acre.
(2) A very low variability between years.
(3) Well-spread production within the growing season.
(4) Approximately half of total growth occurring after January 1.
For the livestock farmer, the implications of these changes
are very great.
The pattern of irrigated pasture reduction was shown
to coincide more closely with the feed requirements of a
beef-breeding herd than with those of a prime-lamb ewe
flock. However, as more calves become available from increased
cow herds in the foothills and high country, and
these are augmented by calves bred on dairy farms, it
seems probable that beef production on the easier country
will become concentrated on finishing, rather than on
breeding. This paper outlines experimental work into
finishing beef cattle at Winchmore Irrigation Research
Station and considers the potential for beef production
in mid-Canterbury in the light of the results obtained
Using concept mapping in the knowledge-to-action process to compare stakeholder opinions on barriers to use of cancer screening among South Asians
BACKGROUND: Using the knowledge-to-action (KTA) process, this study examined barriers to use of evidence-based interventions to improve early detection of cancer among South Asians from the perspective of multiple stakeholders. METHODS: In 2011, we used concept mapping with South Asian residents, and representatives from health service and community service organizations in the region of Peel Ontario. As part of concept mapping procedures, brainstorming sessions were conducted with stakeholders (n = 53) to identify barriers to cancer screening among South Asians. Participants (n = 46) sorted barriers into groups, and rated barriers from lowest (1) to highest (6) in terms of importance for use of mammograms, Pap tests and fecal occult blood tests, and how feasible it would be to address them. Multi-dimensional scaling, cluster analysis, and descriptive statistics were used to analyze the data. RESULTS: A total of 45 unique barriers to use of mammograms, Pap tests, and fecal occult blood tests among South Asians were classified into seven clusters using concept mapping procedures: patientâs beliefs, fears, lack of social support; health system; limited knowledge among residents; limited knowledge among physicians; health education programs; ethno-cultural discordance with the health system; and cost. Overall, the top three ranked clusters of barriers were âlimited knowledge among residents,â âethno-cultural discordance,â and âhealth education programsâ across surveys. Only residents ranked âcostâ second in importance for fecal occult blood testing, and stakeholders from health service organizations ranked âlimited knowledge among physiciansâ third for the feasibility survey. Stakeholders from health services organizations ranked âlimited knowledge among physiciansâ fourth for all other surveys, but this cluster consistently ranked lowest among residents. CONCLUSION: The limited reach of cancer control programs to racial and ethnic minority groups is a critical implementation issue that requires attention. Opinions of community service and health service organizations on why this deficit in implementation occurs are fundamental to understanding the solutions because these are the settings in which evidence-based interventions are implemented. Using concept mapping within a KTA process can facilitate the engagement of multiple stakeholders in the utilization of study results and in identifying next steps for action
Corrections to scaling for percolative conduction: anomalous behavior at small L
Recently Grassberger has shown that the correction to scaling for the
conductance of a bond percolation network on a square lattice is a nonmonotonic
function of the linear lattice dimension with a minimum at , while this
anomalous behavior is not present in the site percolation networks. We perform
a high precision numerical study of the bond percolation random resistor
networks on the square, triangular and honeycomb lattices to further examine
this result. We use the arithmetic, geometric and harmonic means to obtain the
conductance and find that the qualitative behavior does not change: it is not
related to the shape of the conductance distribution for small system sizes. We
show that the anomaly at small L is absent on the triangular and honeycomb
networks. We suggest that the nonmonotonic behavior is an artifact of
approximating the continuous system for which the theory is formulated by a
discrete one which can be simulated on a computer. We show that by slightly
changing the definition of the linear lattice size we can eliminate the minimum
at small L without significantly affecting the large L limit.Comment: 3 pages, 4 figures;slightly expanded, 2 figures added. Accepted for
publishing in Phys. Rev.
Long-term prevalence and predictors of prolonged grief disorder amongst bereaved cancer caregivers: A cohort study
Context: The short-term impact of prolonged grief disorder (PGD) following bereavement is well documented. The longer term sequelae of PGD however are poorly understood, possibly unrecognized, and may be incorrectly attributed to other mental health disorders and hence undertreated.
Objectives: The aims of this study were to prospectively evaluate the prevalence of PGD three years post bereavement and to examine the predictors of long-term PGD in a population-based cohort of bereaved cancer caregivers.
Methods: A cohort of primary family caregivers of patients admitted to one of three palliative care services in Melbourne, Australia, participated in the study (n = 301). Sociodemographic, mental health, and bereavement-related data were collected from the caregiver upon the patient\u27s admission to palliative care (T1). Further data addressing circumstances around the death and psychological health were collected at six (T2, n = 167), 13 (T3, n = 143), and 37 months (T4, n = 85) after bereavement.
Results: At T4, 5% and 14% of bereaved caregivers met criteria for PGD and subthreshold PGD, respectively. Applying the total PGD score at T4, linear regression analysis found preloss anticipatory grief measured at T1 and self-reported coping measured at T2 were highly statistically significant predictors (both p \u3c 0.0001) of PGD in the longer term.
Conclusion: For almost 20% of caregivers, the symptoms of PGD appear to persist at least three years post bereavement. These findings support the importance of screening caregivers upon the patient\u27s admission to palliative care and at six months after bereavement to ascertain their current mental health. Ideally, caregivers at risk of developing PGD can be identified and treated before PGD becomes entrenched
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