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Many types of vital research require protection of communication and information provided confidentially by research participants. In Canada, apart from information collected under the Statistics Act, the only option is a common law balancing test that creates uncertainty insofar as law is made after the fact. This paper explores the option of statute-based protection from the outset. It examines two such protections that have been in place in the United States for decades—revealing their strengths and weaknesses and how they may be applied in the Canadian context.
We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5×106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or high-explosive detonation. This morphology has not been reported previously in cosmic material, but has been observed in terrestrial impact material. This is the first highly enriched, discrete layer of NDs observed in glacial ice anywhere, and its presence indicates that ice caps are important archives of ET events of varying magnitudes. Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at numerous North American sites in a sedimentary layer, the Younger Dryas boundary layer (YDB), dating to 12.9 ± 0.1 ka. However, more investigation is needed to confirm this association.
A suite of Arctic and Antarctic products is being prepared from Advanced
Very High Resolution Radiometer (AVHRR) and ancillary data as part of NASA’s
Polar Pathfinder effort. These products consist of twice-daily gridded
fields of clear-sky surface temperature, surface albedo and cloud fraction,
as well as daily ice velocities, for 1983–96. The products and their
production methodology are summarized here, with examples demonstrating
applications of the Pathfinder products for process studies and
Examinations of the demands on public health workers after disaster exposure have been limited. Workers provide emergency care while simultaneously risking injury, damage to personal property, and threats to their own and their family's safety. We examined the disaster management experiences of 4323 Florida Department of Health workers 9 months after their response to 4 hurricanes and 1 tropical storm during a 7-week period in August and September of 2004.
Participants completed a self-report questionnaire focused on work performance, mental and physical health, daily functioning, sleep disturbance, physiological arousal, and injury and work demand at the time of the hurricanes, and answered open-ended questions that described their experiences in more detail.
A qualitative analysis conducted from the write-in data yielded 4 domains: (1) work/life balance; (2) training for disaster response role; (3) workplace support; and (4) recovery.
Study findings highlighted a number of concerns that are important to public health workers who provide emergency care after a disaster and, in particular, multiple disasters such as during the 2004 hurricane season. The findings also yielded important recommendations for emergency public health preparedness. (Disaster Med Public Health Preparedness. 2013;0:1–7)
We examined the relationship of probable posttraumatic stress disorder (PTSD), probable depression, and increased alcohol and/or tobacco use to disaster exposure and work demand in Florida Department of Health workers after the 2004 hurricanes.
Participants (N = 2249) completed electronic questionnaires assessing PTSD, depression, alcohol and tobacco use, hurricane exposure, and work demand.
Total mental and behavioral health burden (probable PTSD, probable depression, increased alcohol and/or tobacco use) was 11%. More than 4% had probable PTSD, and 3.8% had probable depression. Among those with probable PTSD, 29.2% had increased alcohol use, and 50% had increased tobacco use. Among those with probable depression, 34% indicated increased alcohol use and 55.6% increased tobacco use. Workers with greater exposure were more likely to have probable PTSD and probable depression (ORs = 3.3 and 3.06, respectively). After adjusting for demographics and work demand, those with high exposure were more likely to have probable PTSD and probable depression (ORs = 3.21 and 3.13). Those with high exposure had increased alcohol and tobacco use (ORs = 3.01 and 3.40), and those with high work demand indicated increased alcohol and tobacco use (ORs = 1.98 and 2.10). High exposure and work demand predicted increased alcohol and tobacco use, after adjusting for demographics, work demand, and exposure.
Work-related disaster mental and behavioral health burden indicate the need for additional mental health interventions in the public health disaster workforce.(Disaster Med Public Health Preparedness. 2013;7:89-95)
Solar energy is abundant and offers significant potential for near-term (2020) and long-term (2050) climate change mitigation. There are a wide variety of solar technologies of varying maturities that can, in most regions of the world, contribute to a suite of energy services. Even though solar energy generation still only represents a small fraction of total energy consumption, markets for solar technologies are growing rapidly. Much of the desirability of solar technology is its inherently smaller environmental burden and the opportunity it offers for positive social impacts. The cost of solar technologies has been reduced significantly over the past 30 years and technical advances and supportive public policies continue to offer the potential for additional cost reductions. Potential deployment scenarios range widely—from a marginal role of direct solar energy in 2050 to one of the major sources of energy supply. The actual deployment achieved will depend on the degree of continued innovation, cost reductions and supportive public policies.
Solar energy is the most abundant of all energy resources. Indeed, the rate at which solar energy is intercepted by the Earth is about 10,000 times greater than the rate at which humankind consumes energy. Although not all countries are equally endowed with solar energy, a significant contribution to the energy mix from direct solar energy is possible for almost every country. Currently, there is no evidence indicating a substantial impact of climate change on regional solar resources.
The rising cost of health care and changing demographic profiles have resulted in the relocation and redistribution of funding and services between rural and urban areas. Most econometric analyses of Canada’s health service use include broad controls by province and rural/urban status, but relatively little econometric work has focused on geographical variation in health service use. Using the Canadian Community Health Survey 2.1, we examined determinants of various measures of health services use by Canadians aged 55 or older across a range of urban and rural areas of residence. Our regression analysis showed that older residents in rural areas made fewer visits to a general practitioner, to a specialist, and to a dentist relative to urban residents. All else being equal, there are no significant differences in hospital nights or in unmet healthcare needs. These differences are significant after controlling for demographic characteristics, socioeconomic status, private health insurance, and health status.
Visual evoked responses to dichoptically presented multifocal stimuli
were recorded for 92 eyes. Two stimulus variants were explored: temporally
sparse and rapidly contrast reversing. We used hierarchal decomposition
(HD) to represent the multifocal responses in terms of a small number of
potentially unique component waveforms that are interrelated in a
multivariate linear autoregressive (MLAR) relationship. The HD method
exploits temporal correlations over a range of delays in the responses to
estimate parallel, feedforward and feedback relationships between the HD
components. Three HD components having temporal interrelationships
constrained (at P < 0.05) to a moving ∼20 ms window could
describe the multifocal responses well (median r2-values up to
90%). HD components were similar for both stimulus types and the component
waveforms were temporally correlated, especially the first and third
components. The data set was large enough to estimate separate HD
components for each multifocal stimulus region. The component waveforms
differed somewhat by region but the MLAR relationships were similar. At
short delays parallel processing dominated. At longer delays the
proportion of response drives that were attributed to feedback and
feedforward relationships grew. Overall HD analysis seems to provide an
informed summary of multifocal responses and insights into their
Temporally sparse stimuli have been found to produce larger multifocal
visual evoked potentials than rapid contrast-reversal stimuli. We compared
the contrast-response functions of conventional contrast-reversing (CR)
stimuli and three grades of temporally sparse stimuli, examining both the
changes in response amplitude and signal-to-noise ratio (SNR). All stimuli
were presented dichoptically to normal adult human subjects. One stimulus
variant, the slowest pattern pulse, had interleaved monocular and
binocular stimuli. Response amplitudes and SNRs were similar for all
stimuli at contrast 0.4 but grew faster with increasing contrast for the
sparser stimuli. The best sparse stimulus provided an SNR improvement that
corresponded to a recording time improvement of 2.6 times relative to that
required for contrast reversing stimuli. Multiple regression of
log-transformed response metrics characterized the contrast-response
functions by fitting power-law relationships. The exponents for the two
sparsest stimuli were significantly larger (P < 0.001) than
for the CR stimuli, as were the mean response amplitudes and
signal-to-noise ratios for these stimuli. The contrast-dependent response
enhancement is discussed with respect to the possible influences of rapid
retinal contrast gain control, or intracortical and cortico-geniculate
Multifocal VEP (mfVEP) responses were obtained from 13 normal human
subjects for nine test conditions, covering three viewing conditions
(dichoptic and left and right monocular), and three different temporal
stimulation forms (rapid contrast reversal, rapid pattern pulse
presentation, and slow pattern pulse presentation). The rapid contrast
reversal stimulus had pseudorandomized reversals of checkerboards in each
visual field region at a mean rate of 25 reversals/s, similar to most
mfVEP studies to date. The rapid pattern pulse presentation had
pseudorandomized presentations of a checkerboard for one frame,
interspersed with uniform grey frames, with a mean rate of 25
presentations/s per region per eye. The slow pattern pulse stimulus
had six presentations/s per region per eye. Recording time was 5.3
min/condition. For dichoptic presentation slow pattern pulse responses
were 4.6 times larger in amplitude than the contrast reversal responses.
Binocular suppression was greatest for the contrast reversal stimulus.
Consideration of the signal-to-noise ratios indicated that to achieve a
given level of reliability, slow pattern pulse stimuli would require half
the recording time of contrast reversal stimuli for monocular viewing, and
0.4 times the recording time for dichoptically presented stimuli. About
half the responses to the slow pattern pulse stimuli had peak value
exceeding five times their estimated standard error. Responses were about
20% smaller in the upper visual field locations. Space–time
decomposition showed that responses to slow pattern pulse were more
consistent across visual field locations. We conclude that the pattern
pulse stimuli, which we term temporally sparse, maintain the visual system
in a high contrast gain state. This more than compensates for the smaller
number of presentations in the run, and provides signal-to-noise
advantages that may be valuable in clinical application.
The Resource Teachers Learning and Behaviour (RTLB) program is a unique special education development in New Zealand. The aim of this program is the creation of a nation-wide network of more than 700 RTLB operating as itinerant consulting teachers providing support in inclusive classrooms. The principles underlying the program are described and an outline provided of the curriculum and methods of delivery. The program also acknowledges the need to address the important bi-cultural elements of New Zealand society. The paper reports on RTLB demographic profiles and the initial responses of teachers to their training. Preliminary indices of program effectiveness are also presented. The paper indicates ways in which the RTLB initiative is likely to develop and notes issues within the New Zealand education system that will both strengthen and constrain the overall development of the program.
Data from a western Kansas feedlot were analyzed to estimate the quantitative impacts of price and performance variables on profits per head from finishing cattle. Sale prices, feeder prices, and corn prices had the most impact on profit variability over time. Differences in sale prices, feeder prices, and feed conversions were important in explaining the difference in steer and heifer profits over time. Results suggest that breakeven prices should be calculated for a range of fed cattle, feeder, and corn prices, and that these three variables need to be stochastic in representative farm modeling efforts.
Quality factors affecting fed cattle prices were examined during a six-month period in southwestern Kansas. Transaction prices were significantly affected by the percentage of cattle expected to grade choice times the choice-to-select carcass price spread, finish uniformity, average weight, dressing percentage, breed, number of cattle purchased by a single packer on a given day, the packer, the feedyard, the day-of-the-week the cattle were sold, and the number of bids received. Asking prices were significantly affected by many of the same factors. Asking and transaction prices reflected approximately 25 percent of the packer value differentials for expected carcass quality grades.
Data from Kansas cattle auctions were analyzed to estimate the impact a wide variety of physical characteristics had upon cow prices. Weight, lot size, health, pregnancy, grade, dressing percent, breed, time of sale, and market location were important factors affecting the differences in cow prices across lots on a given day. Results suggest that producers interested in maximizing the price they receive for their cows should market healthy cows in desirable lot sizes at higher dressing percentages.
The enterprise budget, whole farm cash flow, and income statement are fundamental tools of farm and ranch management. The “Microcomputer Budget Management System” (MBMS) is a microcomputer software package that facilitates the storage and use of information for crop and livestock budgeting. It performs the calculations for several1 enterprise budgeting formats and for preparation of whole farm resource use reports and financial statements. The MBMS also includes internal machinery and irrigation cost calculation routines.
MBMS was developed for use by extension staff, researchers, lenders, consultants, and operators of diversified farms and ranches with many enterprises that use enterprise and whole farm budgeting for analysis and planning activities. The flexibility and detailed nature of the program requires the user to have knowledge of enterprise budgeting and operation of complex computer programs. This paper presents a discussion of the features and capabilities of the software and the computational procedures used in the cost calculations.
The final effort of the CLIMAP project was a study of the last interglaciation, a time of minimum ice volume some 122,000 yr ago coincident with the Substage 5e oxygen isotopic minimum. Based on detailed oxygen isotope analyses and biotic census counts in 52 cores across the world ocean, last interglacial sea-surface temperatures (SST) were compared with those today. There are small SST departures in the mid-latitude North Atlantic (warmer) and the Gulf of Mexico (cooler). The eastern boundary currents of the South Atlantic and Pacific oceans are marked by large SST anomalies in individual cores, but their interpretations are precluded by no-analog problems and by discordancies among estimates from different biotic groups. In general, the last interglacial ocean was not significantly different from the modern ocean. The relative sequencing of ice decay versus oceanic warming on the Stage 6/5 oxygen isotopic transition and of ice growth versus oceanic cooling on the Stage 5e/5d transition was also studied. In most of the Southern Hemisphere, the oceanic response marked by the biotic census counts preceded (led) the global ice-volume response marked by the oxygen-isotope signal by several thousand years. The reverse pattern is evident in the North Atlantic Ocean and the Gulf of Mexico, where the oceanic response lagged that of global ice volume by several thousand years. As a result, the very warm temperatures associated with the last interglaciation were regionally diachronous by several thousand years. These regional lead-lag relationships agree with those observed on other transitions and in long-term phase relationships; they cannot be explained simply as artifacts of bioturbational translations of the original signals.