2,238 research outputs found
Airborne tracking sunphotometer apparatus and system
An airborne tracking Sun photometer apparatus has a rotatable dome. An azimuth drive motor is connected to rotate the dome. The dome has an equatorial slot. A cylindrical housing is pivotally mounted inside the dome at the equatorial slot. A photometer is mounted in the housing to move in the equatorial slot as the housing pivots. The photometer has an end facing from the slot with an optical flat transparent window. An elevation drive motor is connected to pivot the cylindrical housing. The rotatable dome is mounted in the bulkhead of an aircraft to extend from the interior of the aircraft. A Sun sensor causes the photometer to track the Sun automatically. Alternatively, the photometer may be oriented manually or by computer
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An overview of the ACE-2 clear sky column closure experiment (CLEARCOLUMN)
As 1 of 6 focused ACE-2 activities, a clear sky column closure experiment (CLEARCOLUMN)
took place in June/July 1997 at the southwest corner of Portugal, in the Canary Islands, and
over the eastern Atlantic Ocean surrounding and linking those sites. Overdetermined sets of
volumetric, vertical profile and columnar aerosol data were taken from the sea surface to~5 km
asl by samplers and sensors at land sites (20–3570 m asl), on a ship, and on 4 aircraft. In
addition, 5 satellites measured upwelling radiances used to derive properties of the aerosol
column. Measurements were made in a wide range of conditions and locations (e.g., the marine
boundary layer with and without continental pollution, the free troposphere with and without
African dust). Numerous tests of local and column closure, using unidisciplinary and multidisciplinary
approaches, were conducted. This paper summarizes the methodological approach, the
experiment sites and platforms, the types of measurements made on each, the types of analyses
conducted, and selected key results, as a guide to the more complete results presented in other
papers in this special issue and elsewhere. Example results include determinations of aerosol
single scattering albedo by several techniques, measurements of hygroscopic effects on particle
light scattering and size, and a wide range in the degree of agreement found in closure tests. In
general, the smallest discrepancies were found in comparisons among (1) different techniques
to measure an optical property of the ambient, unperturbed aerosol (e.g., optical depth, extinction,
or backscatter by sunphotometer, lidar, and/or satellite) or (2) different techniques to
measure an aerosol that had passed through a common sampling process (e.g., nephelometer
and size spectrometer measurements with the same or similar inlets, humidities and temperatures).
Typically, larger discrepancies were found between techniques that measure the ambient,
unperturbed aerosol and those that must reconstruct the ambient aerosol by accounting for
(a) processes that occur during sampling (e.g., aerodynamic selection, evaporation of water and
other volatile material) or ( b) calibrations that depend on aerosol characteristics (e.g., sizedependent
density or refractive index). A primary reason for the discrepancies in such cases is
the lack of validated hygroscopic growth models covering the necessary range of particle sizes
and compositions. Other common reasons include (1) using analysis or retrieval techniques
that assume aerosol properties (e.g., density, single scattering albedo, shape) that do not apply
in all cases and (2) using surface measurements to estimate column properties. Taken together,
the ACE-2 CLEARCOLUMN data set provides a large collection of new information on the
properties of the aerosol over the northeast Atlantic Ocean. CLEARCOLUMN studies have
also pointed to improved techniques for analyzing current and future data sets (including
satellite data sets) which will provide a more accurate and comprehensive description of the
Atlantic–European–African aerosol. Thus they set the stage for an improved regional quantification
of radiative forcing by anthropogenic aerosols
Management of gangrenous sigmoid volvulus at Tenwek Hospital in western Kenya
Background: Bowel gangrene has a negative impact on outcomes of patients with sigmoid volvulus (SV). This study aimed at evaluating the management and outcomes of patients with gangrenous sigmoid volvulus and assessing the utility of primary anastomosis as a management option. Methods: An 11-year (January 2006-December 2016) descriptive retrospective chart review of patients managed for SV at Tenwek Hospital in Bomet, Kenya.Results: A total of 46 cases were identified, representing 25.4% of all cases of SV noted during the study period. The group had a mean age of 47.3 years (range 15-81), mean symptom duration of 2.2 days (range 2 hours-7 days) and a male predominance of 87%. Primary anastomosis (PA) without a proximal diverting colostomy was performed in 24 cases and a Hartmann's procedure (HP) was performed in 22 cases. Patients who had a HP were noted to have had a longer duration of symptoms and a higher incidence of peritonitis than those who had a PA (2.7 vs 1.8 days, P = 0.02; and 72% vs 42%, P = 0.04). All patients with concurrent colonic perforation (n = 3) had a HP. Seven patients died, giving an overall mortality of 15.2%. There was an anastomotic leak rate of 4.2% and a mortality rate of 8.3% among the subset of patients who had a PA.Conclusions: Primary anastomosis can be safely performed with good outcomes in patients with gangrenous SV, and the presence of bowel gangrene does not mandate a diverting colostomy. Keywords: sigmoid volvulus; bowel gangrene; primary anastomosis; colostomy; bowel obstructio
Science requirements and feasibility/design studies of a very-high-altitude aircraft for atmospheric research
The advantages and shortcomings of currently available aircraft for use in very high altitude missions to study such problems as polar ozone or stratosphere-troposphere exchange pose the question of whether to develop advanced aircraft for atmospheric research. To answer this question, NASA conducted a workshop to determine science needs and feasibility/design studies to assess whether and how those needs could be met. It was determined that there was a need for an aircraft that could cruise at an altitude of 30 km with a range of 6,000 miles with vertical profiling down to 10 km and back at remote points and carry a payload of 3,000 lbs
Stratosphere-troposphere exchange project management
The purpose is to manage the Stratosphere Troposphere Exchange Project (STEP). This includes holding and planning science team meetings, organizing sessions at conferences devoted to the results and objectives of STEP field programs, putting together special journal issues or special sections of journal issues devoted to the results of STEP, and planning and producing technical memoranda on STEP. Summary of progress and results are given
Intrinsic and extrinsic factors drive ontogeny of early-life at-sea behaviour in a marine top predator
Young animals must learn to forage effectively to survive the transition from parental provisioning to independent feeding. Rapid development of successful foraging strategies is particularly important for capital breeders that do not receive parental guidance after weaning. The intrinsic and extrinsic drivers of variation in ontogeny of foraging are poorly understood for many species. Grey seals (Halichoerus grypus) are typical capital breeders; pups are abandoned on the natal site after a brief suckling phase, and must develop foraging skills without external input. We collected location and dive data from recently-weaned grey seal pups from two regions of the United Kingdom (the North Sea and the Celtic and Irish Seas) using animal-borne telemetry devices during their first months of independence at sea. Dive duration, depth, bottom time, and benthic diving increased over the first 40 days. The shape and magnitude of changes differed between regions. Females consistently had longer bottom times, and in the Celtic and Irish Seas they used shallower water than males. Regional sex differences suggest that extrinsic factors, such as water depth, contribute to behavioural sexual segregation. We recommend that conservation strategies consider movements of young naĂŻve animals in addition to those of adults to account for developmental behavioural changes
Impact Evaluation of the European Employment Strategy in Ireland. ESRI General Papers
Recent years have seen dramatic growth in employment following unprecedented economic
growth and development during the 1990s. Total employment in Ireland grew by a
remarkable 534,000, or by 46%, in the eight years from 1993 to 2001, and over 220,000 of
this was achieved between 1998 and 2001. In very recent years, the rate of growth in
employment fallen somewhat, from a peak of almost 7% in 1997-1998 to about 4% in 2000-
2001.
The rapid growth in the economy and in employment after 1993 led to a steady decline in
unemployment from 220,000 in 1993 to 127,000 in the 2nd quarter of 1998 and to 65,000 in
the 2nd quarter of 2001. The unemployment rate thus fell from 15.7% of the labour force in
1993 to 7.8% in the 2nd quarter of 1998 and to 3.7% in the 2nd quarter of 2001. With the
deterioration in the international economy, and the slowdown in the Irish growth rate in 2001,
unemployment increased to just under 80,000, or 4.3% of the labour force, in the 3rd quarter
of 2001
Navigating uncertain waters:a critical review of inferring foraging behaviour from location and dive data in pinnipeds
In the last thirty years, the emergence and progression of biologging technology has led to great advances in marine predator ecology. Large databases of location and dive observations from biologging devices have been compiled for an increasing number of diving predator species (such as pinnipeds, sea turtles, seabirds and cetaceans), enabling complex questions about animal activity budgets and habitat use to be addressed. Central to answering these questions is our ability to correctly identify and quantify the frequency of essential behaviours, such as foraging. Despite technological advances that have increased the quality and resolution of location and dive data, accurately interpreting behaviour from such data remains a challenge, and analytical methods are only beginning to unlock the full potential of existing datasets. This review evaluates both traditional and emerging methods and presents a starting platform of options for future studies of marine predator foraging ecology, particularly from location and two-dimensional (time-depth) dive data. We outline the different devices and data types available, discuss the limitations and advantages of commonly-used analytical techniques, and highlight key areas for future research. We focus our review on pinnipeds - one of the most studied taxa of marine predators - but offer insights that will be applicable to other air-breathing marine predator tracking studies. We highlight that traditionally-used methods for inferring foraging from location and dive data, such as first-passage time and dive shape analysis, have important caveats and limitations depending on the nature of the data and the research question. We suggest that more holistic statistical techniques, such as state-space models, which can synthesise multiple track, dive and environmental metrics whilst simultaneously accounting for measurement error, offer more robust alternatives. Finally, we identify a need for more research to elucidate the role of physical oceanography, device effects, study animal selection, and developmental stages in predator behaviour and data interpretation
“When I was surfing with those guys I was surfing with family.” A Grounded Exploration of Program Theory within the Jimmy Miller Memorial Foundation Surf Therapy Intervention
Surf therapy is an intervention increasingly being utilized to tackle a range of health inequalities for military veterans. While increasing evidence demonstrates the effectiveness of surf therapy, there has been limited exploration of program theoretical explanations as to how it achieves positive outcomes. Theoretical understanding is important as it allows for service optimization, monitoring and further development. The current study utilized a pragmatic qualitative approach to explore theoretical mediators of the outcomes of Jimmy Miller Memorial Foundation (JMMF) surf therapy intervention. JMMF is a California (USA)-based program supporting military veterans facing mental and physical health challenges. Eighteen people who had participated in JMMF interventions (12 males and 6 females; mean age = 42 years; standard deviation = 11 years; range 28-71) were interviewed in depth about their experiences of the surf therapy intervention. Data were analyzed through constant comparative analysis and memo writing in line with pragmatic grounded theory. Two core intervention categories (relating to service delivery) were identified: “Constant challenge tackled at own pace” and “A non-judgmental familial safe space.” A further three individual categories (relating to participants) were identified: “Accomplishment,” “Respite,” and “Social Connections.” One contextualized category was identified; “Physical Therapeutic Elements.” Furthermore, a culture of “Reframing Failure” pervaded every element of the intervention. The findings demonstrated strong links to self-determination and flow theories which suggest potential theoretical frameworks for better understanding of the constructs that underpin surf therapy. The findings provide empirical evidence as to how best to optimize and expand JMMF service delivery in the US and potentially for surf therapy in wider veteran population
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