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The attention of driver traveling along a long straight line of prairie highway is easy to be distracted. In this paper, the correlation of straight line length and driver's attention is studied through laboratory simulation experiment and regression analysis. It can be theoretically concluded that the maximum straight line length for prairie highway within which the driver could travel with proper attention is 5km. This study is significant both for prairie highway construction and Intelligent Transportation System.

Byline: Bruce Millett (1), W. Carter Johnson (2), Glenn Guntenspergen (3) Abstract: The Prairie Pothole Region (PPR) is unique to North America. Its millions of wetlands and abundant ecosystem goods and services are highly sensitive to wide variations of temperature and precipitation in time and space characteristic of a strongly continental climate. Precipitation and temperature gradients across the PPR are orthogonal to each other. Precipitation nearly triples from west to east from approximately 300 mm/year to 900 mm/year, while mean annual temperature ranges from approximately 1degC in the north to nearly 10degC in the south. Twentieth-century weather records for 18 PPR weather stations representing 6 ecoregions revealed several trends. The climate generally has been getting warmer and wetter and the diurnal temperature range has decreased. Minimum daily temperatures warmed by 1.0degC, while maximum daily temperatures cooled by 0.15degC. Minimum temperature warmed more in winter than in summer, while maximum temperature cooled in summer and warmed in winter. Average annual precipitation increased by 49 mm or 9%. Palmer Drought Severity Index (PDSI) trends reflected increasing moisture availability for most weather stations however, several stations in the western Canadian Prairies recorded effectively drier conditions. The east-west moisture gradient steepened during the twentieth century with stations in the west becoming drier and stations in the east becoming wetter. If the moisture gradient continues to steepen, the area of productive wetland ecosystems will shrink. Consequences for wetlands would be especially severe if the future climate does not provide supplemental moisture to offset higher evaporative demand. Author Affiliation: (1) Department of Geography, South Dakota State University, Box 504, Brookings, SD, 57007, USA (2) Department of Horticulture, Forestry, Landscape, and Parks, South Dakota State University, Brookings, SD, 57007, USA (3) U. S. Geological Survey, Patuxent Wildlife Research Center, Laurel, MD, 20708, USA Article History: Registration Date: 09/12/2008 Received Date: 27/06/2006 Accepted Date: 20/10/2008 Online Date: 19/02/2009

Byline: Tyler Joseph Tarnoczi (1), Fikret Berkes (1) Abstract: Successful adaptation assumes the availability of appropriate information for groups potentially impacted by climate change. This research examines information available to help farmers in the Canadian Prairies to adapt, with focus on information related to soil and water conservation practices, such as preserving wetlands and maintaining shelterbelts and groundcover, considered particularly important for this region. Results of 28 semi-structured interviews carried out with producers in two Prairie provinces, Alberta and Manitoba, revealed that information regarding soil and water conservation practices comes from a variety of sources. These included industry, government, producer and conservation organizations, social sources of information and personal experience, and media. Producers were more open to new practices when they could learn them through observation, trials, and two-way dialogue. There appears to be a general lack of producer organization involvement, and dearth of government information, direction, and coordination for climate change adaptation. Information from government and producer organizations can be important for the co-production of knowledge that can lead to successful adaptation. Author Affiliation: (1) Natural Resources Institute, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada Article History: Registration Date: 10/11/2009 Received Date: 28/08/2009 Accepted Date: 09/11/2009 Online Date: 28/11/2009

The True Prairie (TP) is a large area in the central U.S. which was a tall grass prairie for thousands of years prior to its conversion to crop land. An analysis of climatically controlling factors indicated that the tall grass prairie is favored by the ratio of warm season precipitation to potential evapotranspiration exceeding 0.75 (west boundary), cold season precipitation less than 38 cm (south boundary), high cold-season frequency of thunderstorms (north boundary), and high drought frequencies (entire region). A 'climate-year' approach was used to assess the temporal and spatial variability of these conditions during the 20th century. This analysis did not reveal any long-term trends in most climate-year types, although there were significant decadal-scale fluctuations, most notably a high frequency of drought-type years in the 1930s and 1950s. However, the well-documented upward trend in precipitation is manifested in an increasing frequency of one climate-year type characterized by above normal cold season precipitation in the southern border area of the TP.

This article reports the findings from a questionnaire survey of university students' life satisfaction in Regina. The results demonstrated that a significant proportion of the 315 respondents were satisfied with their lives (N = 240, 76.2%). With regard to degree of satisfaction with different aspects of life, respondents expressed that they were most satisfied with relationship with mother, living environment, relationships with close friends, relationships with siblings, and living arrangement. Multiple ordinary least-squares regression analyses revealed that respondents who indicated a higher socio-economic status, achieved a higher grade point average, and were more satisfied with their academic experience, self-esteem, relationship with significant other, and living conditions, expressed a markedly higher level of satisfaction with life.

From 1988 to 1992 the north-central plains of North America had a drought that was followed by a wet period that continues to the present (1997). Data on the hydrology of the Cottonwood Lake area (CWLA) collected for nearly 10 years before, and during, the recent dry and wet periods indicate that some prairie pothole wetlands served only a recharge function under all climate conditions. Transpiration from groundwater around the perimeter of groundwater discharge wetlands drew water from the wetlands by the end of summer, even during very wet years. Long-term records of a climate index (Palmer Drought Severity Index), stream discharge (Pembina River), and lake level (Devils Lake) were used to put the 17-year CWLA record into a longer term perspective. In addition, proxy records of climate determined from fossils in the sediments of Devils Lake were also used. These data indicate that the drought of 1988-92 may have been the second worst of the 20th century, but that droughts of that magnitude, and worse, were common during the past 500 years. In contrast, the present wet period may be the wettest it has been during the past 130 years, or possibly the past 500 years. Keywords: wetland hydrology, Palmer Drought Severity Index, Devils Lake, Pembina River

Modelling results of precision temperature logs made to depths of up to several hundred meters in numerous wells in the Canadian Prairie provinces (mostly Alberta) show evidence of average warming at the ground surface (GST) of 2.1 K (standard deviation = 0.9 K) mostly in the second half of this century. The GST warming signal for which higher frequency noise is cut off by the earth, which acts as a low-pass filter, correlates with the surface air warming (SAT) measured at screen level. A spatial comparison is made between the SAT warming and the GST warming for the last four decades in this region. A GIS (Geographic Information System) area cross tabulation was performed through the intersection of the classes of the ground and surface warming maps with a resulting contingency coefficient C = 0.805. Identical grid samples extracted from the ground warming and surface warming maps were related statistically with a resulting correlation coefficient of [Tau] = 0.75. Differences in the magnitudes of the warming exist due to the limited number of compatible data sets, errors in ground warming and air warming reconstructions, and land surface changes affecting the energy balance and subsurface heat fluxes. The influence of these effects requires further study. It is unlikely that all of the sites for which GST warming has been proven to correlate with air warming would have identical topography, vegetation, and hydrogeological disturbances for an area as large as the one under study (about 720,000 [km.sup.2]). The warming effect in the study area, as preserved by the ground, is mainly climate related.

The amount of water held in individual wetland basins depends not only on local climate patterns but also on groundwater flow regime, soil permeability, and basin size. Most wetland basins in the northern prairies hold water in some years and are dry in others. To assess the potential effect of climate change on the number of wetland basins holding water in a given year, one must first determine how much of the variability in number of wet basins is accounted for by climatic variables. I used multiple linear regression to examine the relationship between climate variables and percentage of wet basins throughout the Prairie Pothole Region of Canada and the United States. The region was divided into three areas: parkland, Canadian grassland, and United States grassland (i.e., North Dakota and South Dakota). The models - which included variables for spring and fall temperature, yearly precipitation, the previous year's count of wet basins, and for grassland areas, the previous fall precipitation - accounted for 63 to 65% of the variation in the number of wet basins. I then explored the sensitivities of the models to changes in temperature and precipitation, as might be associated with increased greenhouse gas concentrations. Parkland wetlands are shown to be much more vulnerable to increased temperatures than are wetlands in either Canadian or United States grasslands. Sensitivity to increased precipitation did not vary geographically. These results have implications for waterfowl and other wildlife populations that depend on availability of wetlands in the parklands for breeding or during periods of drought in the southern grasslands.

We assessed the potential effects of a greenhouse gas-induced global climate change on the hydrology and vegetation of a semi-permanent prairie wetland using a spatially-defined, rule-based simulation model. An 11-yr simulation was run using current versus enhanced greenhouse gas climates. Projections of climatic change were from the Goddard Institute for Space Studies (GISS) general circulation model. Simulations were also run using a range of temperature (+2 and +4 degrees C) and precipitation change values (-20, -10, 0, +10, +20%) to determine the responsiveness of wetland vegetation and hydrology to a variety of climate scenarios. Maximum water depths were significantly less under the enhanced greenhouse gas scenario than under the current climate. The wetland dried in most years with increased temperature and changes in precipitation. Simulations also revealed a significant change in the vegetation, from a nearly balanced emergent cover to open water ratio to a completely closed basin with no open water areas. Simulations over a range of climate change scenarios showed that precipitation changes (particularly increases) had a greater impact on water levels and cover ratios when the temperature increase was moderate (+2 degrees C). These potential changes in wetland hydrology and vegetation could result in a dramatic decline in the quality of habitat for breeding birds, particularly waterfowl. Continued research on climate and wetland modeling is needed.

Because both intrinsic and extrinsic factors influence insect population dynamics, operating at a range of temporal and spatial scales, it is difficult to assess their contributions. Long-term studies are ideal for assessing the relative contributions of multiple factors to abundance and community dynamics. Using data spanning 25 years, we investigate the contributions of weather at annual and decadal scales, fire return interval, and grazing by bison to understand the dynamics of abundance and community composition in grasshopper assemblages from North American continental grassland. Each of these three primary drivers of grassland ecosystem dynamics affects grasshopper population and community dynamics. Negative feedbacks in abundances, as expected for regulated populations, were observed for all feeding guilds of grasshoppers. Abundance of grasshoppers did not vary in response to frequency of prescribed burns at the site. Among watersheds that varied with respect to controlled spring burns and grazing by bison, species composition of grasshopper assemblages responded significantly to both after 25 years. However, after more than 20 years of fire and grazing treatments, the number of years since the last fire was more important than the managed long-term fire frequency per se. Yearly shifts in species composition (1983-2005), examined using non-metric multidimensional scaling and fourth-corner analysis, were best explained by local weather events occurring early in grasshopper life cycles. Large-scale patterns were represented by the Palmer Drought Severity Index and the North Atlantic Oscillation (NAO). The NAO was significantly correlated with annual mean frequencies of grasshoppers, especially for forb- and mixed-feeding species. Primary grassland drivers-fire, grazing and weather-contributing both intrinsic and extrinsic influences modulate long-term fluctuations in grasshopper abundances and community taxonomic composition.

Prairie rattlesnakes (Crotalus viridis) received exposure to a mouse carcass misted with diluted perfume during predatory strikes, just before or after striking, or in the absence of a strike. They then received a choice between a pair of nonenvenomated carcasses, one misted with the perfume and the other misted with a novel solution. Snakes that struck a perfume-misted carcass preferred the nonenvenomated carcass with chemical cues matching those on the carcass they had struck. However, exposure to chemical cues without striking produced no such preference even when the concentration of perfume solution was 100 times that used in the strike condition. Moreover, exposure to chemical cues just before or after the striking of an unscented carcass produced no subsequent preference for a carcass with matching cues. These results indicate the importance of the predatory strike rather than simple familiarization in the formation of chemical preferences in rattlesnakes.

Among other foci, recent research on adaptation to climatic variability and change has sought to evaluate the merit of adaptation generally, as well as the suitability of particular adaptations. Additionally, there is a need to better understand the likely uptake of adaptations. For example, diversification is one adaptation that has been identified as a potential farm-level response to climatic variability and change, but its adoption by farmers for this reason is not well understood. This paper serves two purposes. The first is to document the adoption of crop diversification in Canadian prairie agriculture for the period 1994-2002, reflect upon its strengths and limitations for managing a variety of risks, including climatic ones, and gauge its likely adoption by producers in response to anticipated climate change. The second purpose is to draw on this case to refine our current understanding of climate change adaptation more generally. Based upon data from over 15 000 operations, it was determined that individual farms have become more specialized in their cropping patterns since 1994, and this trend is unlikely to change in the immediate future, notwithstanding anticipated climate change and the known risk-reducing benefits of crop diversification. More broadly, the analysis suggests that 'suitable' and even 'possible' climate change adaptations need to be more rigorously assessed in order to understand their wider strengths and limitations.

Upon its premiere in 2014, ABC's black-ish introduced network television audiences to a unique representation of Black middle-class (BMC) life that defies existing norms in the genre of domestic situation comedy. To make sense of the significant cultural work the series performs, this article introduces a new framework for categorizing how we understand televisual representations of Black middle classness-through surreal, real, or honest lenses-and argues black-ish, unlike its predecessors, is committed to producing honesty. An honest view of BMC life requires a willingness to explore how it feels to negotiate persistent friction between one's racial and class positionality. Black-ish achieves honesty through the series' title and its deployment of three key devices: self-conscious conversations about race and class, voiceovers that allow access to characters' internal dialogues, and 'teachable moments' designed to educate (largely-white) audiences about BMC experiences. In the end, honesty offers a more fruitful pathway for (re)imagining and engaging with BMC figures in popular television and BMC people in everyday life., Author(s): Gretta Blackwell [sup.1] Author Affiliations: (1) https://ror.org/0449kf092, grid.262103.4, 0000 0004 0456 3986, Languages & Communication, Prairie View A&M University, , P.O. Box 519 Mail Stop 2220, Prairie View, 77446, [...]

Woody encroachment-the spread of woody vegetation in open ecosystems-is a common threat to grasslands worldwide. Reversing encroachment can be exceedingly difficult once shrubs become established, particularly clonal species that resprout following disturbance. Single stressors are unlikely to reverse woody encroachment, but using multiple stressors in tandem could be successful in slowing or reversing encroachment. We explored whether increasing fire frequency in conjunction with multi-year drought could reduce growth and survival of encroaching shrubs in a tallgrass prairie in northeastern Kansas, USA. Passive rainout shelters (~ 50% rainfall reduction) were constructed over mature clonal shrubs (Cornus drummondii) and co-existing C 4 grasses in two fire treatments (1-year and 4-year burn frequency). Leaf- and whole-plant level physiological responses to drought and fire frequency were monitored in shrubs and grasses from 2019 to 2022. Shrub biomass and stem density following fire were unaffected by five years of consecutive drought treatment, regardless of fire frequency. The drought treatment had more negative effects on grass leaf water potential and photosynthetic rates compared to shrubs. Shrub photosynthetic rates were remarkably stable across each growing season. Overall, we found that five consecutive years of moderate drought in combination with fire was not sufficient to reduce biomass production or stem density in an encroaching clonal shrub (C. drummondii). These results suggest that moderate but chronic press-drought events do not sufficiently stress encroaching clonal shrubs to negatively impact their resilience following fire events, even when fire frequency is high., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Whole-plant hydraulics provide important information about responses to water limitation and can be used to understand how plant communities may change in a drier climate when measured on multiple species. Here, we measured above- and belowground hydraulic traits in Cornus drummondii, an encroaching shrub within North American tallgrass prairies, and Andropogon gerardii, a dominant C 4 grass, to assess the potential hydraulic responses to future drought as this region undergoes woody expansion. Shelters that reduced precipitation by 50% and 0% were built over shrubs and grasses growing in sites that are burned at 1-year and 4-year frequencies. We then measured aboveground (K shoot ), belowground (K root ), and whole-plant maximum hydraulic conductance (K plant ) in C. drummondii and K root in A. gerardii. We also measured vulnerability to embolism (P 50 ) in C. drummondii stems. Overall, we show that: (1) A. gerardii had substantially greater K root than C. drummondii; (2) belowground hydraulic functioning was linked with aboveground processes; (3) above- and belowground C. drummondii hydraulics were not negatively impacted by the rainfall reductions imposed here. These results suggest that a multi-year drought will not ameliorate rates of woody expansion and highlight key differences in aboveground and belowground hydraulics for dominant species within the same ecosystem., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Byline: Jennifer Stuart (1), Mark Fondacaro (2), Scott A. Miller (1), Veda Brown (3), Eve M. Brank (1) Keywords: Procedural justice; Family conflict; Deviant peers; Juvenile delinquency Abstract: The involvement of adolescents with deviant peer groups is one of the strongest proximal correlates to juvenile delinquency and stems from a variety of causes. Past research has linked ineffective parenting with peer variables, including deviant peer group involvement and peer conflict during adolescence. In this study, adolescents' appraisals of procedural justice within the family (adolescents' appraisals of how fairly they are treated by parents in the process of resolving family conflict) were examined as one aspect of effective parenting that may relate to deviant peer group involvement in early adolescence. Data from 1660 middle school students (ages 11--14, mean = 12.6) indicated that higher appraisals by adolescents of procedural justice during family conflict resolution were related to lower levels of both peer conflict and deviant peer group involvement. A structural model was tested in which the relationship between adolescents' appraisals of procedural justice in the family and deviant peer group involvement was partially mediated by measures of peer conflict. This model was found to have adequate fit to the data, indicating that part of the relationship between procedural justice appraisals and deviant peer group involvement can be explained by levels of peer conflict. Implications of these findings are discussed. Author Affiliation: (1) University of Florida, Gainesville, USA (2) John Jay College of Criminal Justice, New York, USA (3) Prairie View A & M University, Prairie View, USA Article History: Registration Date: 10/05/2007 Received Date: 23/08/2006 Accepted Date: 09/05/2007 Online Date: 20/06/2007

Byline: Michael A. Wulder (1), Trisalyn A. Nelson (2), Chris Derksen (3), David Seemann (1) Abstract: Twenty-four winter seasons (1978--2002) of mean February snow water equivalent (SWE) values were analyzed in an exploration of the spatial pattern of temporal variability in snow cover across the non-mountainous interior of Canada. The SWE data were derived from space-borne passive microwave brightness temperatures processed with a land cover-sensitive suite of algorithms. Spatial patterns in the frequency and amount of variability were investigated on an annual basis through comparisons with average trends over all 24 years. Changes in temporal variability through time were also investigated by comparing three eight year time periods to general trends. Analyses were synthesized at the ecozone scale in order to link results both to potential land cover influences on algorithm performance and climatological variability in SWE. Prairie and northern ecozones were typically found to be the most variable in terms of SWE magnitude. Analyses indicate that non-treed land cover classes are generally more variable than treed classes. The results also indicate that extreme weather events appear to be occurring with increasing consistency in the Prairie and Arctic regions. Discerning climatologically significant variability in the time series, compared to algorithm-related issues can be a challenge, but in an era of eroding surface observing networks the passive microwave time series represents an important resource for monitoring and detecting trends and variability in terrestrial snow cover. Author Affiliation: (1) Canadian Forest Service (Pacific Forestry Centre), Natural Resources Canada, Victoria, V8Z 1M5, British Columbia, Canada (2) Department of Geography, University of Victoria, Victoria, V8W 3P5, British Columbia, Canada (3) Climate Research Division, Climate Processes Section, Environment Canada, Downsview, M3H 5T4, Ontario, Canada Article History: Registration Date: 01/06/2006 Received Date: 29/11/2004 Accepted Date: 12/05/2006 Online Date: 15/02/2007

Increased gas emissions from soil into the atmosphere are one form of ecosystem feedback in response to climate change. Soil temperature plays a critical role in the soil emission of carbon dioxide (CO 2 ) and nitrous oxide (N 2 O) suggesting that the release of gases can be reduced by regulating soil temperature. This study proposes a green microencapsulated phase-change material (mPCM) as a soil temperature regulator due to its ability to absorb and release heat during temperature phase transition. The objective is to test how mPCM in soil mixtures influences CO 2 and N 2 O fluxes under laboratory-controlled conditions. For this purpose, a series of soil incubations were carried out with different temperature regimes and soil moisture. The test results revealed that at 20% soil moisture mPCM reduced cumulative CO 2 emissions from the soil by 16.4% during the thawing stage and by 20.5% during the freezing stage. At 25% soil moisture, mPCM showed a greater effect reducing cumulative CO 2 emissions by 23.9% during the thawing stage and by 24.2% during the freezing stage. At below-zero temperatures, mPCM reduced the total N 2 O flux by 11.6% at 20% soil moisture and by 26.0% at 25% soil moisture, compared to soil without mPCM. As soil moisture increased, the effects of mPCM on CO 2 and N 2 O fluxes became more pronounced. Cyclic freezing and thawing of soil led to an increase in gas flux. This variation was reduced by the mPCM due to its ability to mitigate the change of soil temperature. Inhibition of the rise in soil temperature due to the inclusion of mPCM reduced the rate of activation of soil mineralization, which reduced gas fluxes. This study demonstrates the potential of mPCM application to reduce greenhouse gas emissions from soil through thermoregulation., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The Prairie Pothole Region (PPR) of the Northern Great Plains is the most important breeding area for waterfowl in North America. Historically, the size of breeding duck populations in the PPR has been highly correlated with spring wetland conditions. We show that one indicator of climate conditions, the Palmer Drought Severity Index (PDSI), is strongly correlated with annual counts (from 1955 to 1996) of both May ponds ([R.sup.2] = 0.72, p < 0.0001) and breeding duck populations ([R.sup.2] = 0.69, p < 0.0001) in the Northcentral U.S., suggesting the utility of PDSI as an index for climatic factors important to wetlands and ducks. We then use this relationship to project future pond and duck numbers based on PDSI values generated from sensitivity analyses and two general circulation model (GCM) scenarios. We investigate the sensitivity of PDSI to fixed changes in temperature of 0 [degrees] C, +1.5 [degrees] C, +2.5 [degrees] C, and +4.0 [degrees] C in combination with fixed changes in precipitation of -10%, +0%, +7%, and +15%, changes spanning the range of typically-projected values for this region from human-induced climatic change. Most (11 of 12) increased temperature scenarios tested result in increased drought (due to greater evapotranspiration under warmer temperatures) and declining numbers of both wetlands and ducks. Assuming a doubling of C[O.sub.2] by 2060, both the equilibrium and transient GCM scenarios we use suggest a major increase in drought conditions. Under these scenarios, Northcentral U.S. breeding duck populations would fluctuate around means of 2.1 or 2.7 million ducks based on the two GCMs, respectively, instead of the present long-term mean of 5.0 million. May pond numbers would fluctuate around means of 0.6 or 0.8 million ponds instead of the present mean of 1.3 million. The results suggest that the ecologically and economically important PPR could be significantly damaged by climate changes typically projected. We make several recommendations for policy and research to help mitigate potential effects. Keywords: effects of global warming, drought, climate change, Prairie Pothole Region, waterfowl breeding ecology, wetlands

Garnet is a common U-bearing mineral in various magmatic and metamorphic rocks with a high U-Pb closure temperature (> 850 °C), rendering it a potentially valuable U-Pb geochronometer. However, a high U (> 10 ppm) garnet reference material that suits both quadrupole and/or multi-collector inductively coupled plasma mass spectrometry (ICP-MS) is yet to be established. This study evaluates a potential reference material for in situ garnet U-Pb analysis with anomalously high U content from the Prairie Lake alkaline complex, Canada. The PL57 garnet, occurring in a calcite ijolite, has high TiO.sub.2 (6.5-15.0 wt%, average 12.7 wt%) and Fe.sub.2O.sub.3 (17.1-21.3 wt%) contents and is a member of the andradite (26-66 mol.%)-morimotoite (18-41 mol.%)-schorlomite (16-35 mol.%) solid solution series. Four samples were dated by U-Pb ID-TIMS to assess reproducibility. Twelve TIMS analyses produced concordant, equivalent results. Garnet PL57 yielded a concordant age of 1156.2 ± 1.2 Ma (2[sigma], n = 10, MSWD = 1.0), based on ten analyses with two results discarded due to possible mineral inclusions (if included, the concordia age is 1156.6 ± 1.8 Ma; n = 12, MSWD = 2.0). PL57 had 27-76 ppm (average 41 ppm) U with Th/U of 0.51-0.68 (average 0.63). The total common Pb content ranged from 0.4 to 3.9 pg (average 1.1 pg). Laser ablation coupled with ICP-MS and high angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging provide direct evidence that U is incorporated and homogeneously distributed within the garnet lattice rather than as defects or pore spaces. Published garnet samples and standards were then tested by calibrating the Willsboro, Mali, Qicun, and Tonglvshan garnet against PL57, which gave accurate ages within the recommended values. Case studies of garnet from the Archean Musselwhite orogenic gold deposit in Canada and the Cenozoic Changanchong and Habo skarn deposits in China yield reliable ages. This suggests that PL57 is a robust U-Pb isotope reference material. The limited variations of U and Pb isotopic ratios, together with the high U concentration and extremely low initial common Pb, make PL57 an ideal calibration and monitor reference material for in situ measurements., Author(s): Dengfeng Li [sup.1] [sup.2], Yu Fu [sup.1] [sup.2], Pete Hollings [sup.3], Roger H. Mitchell [sup.3], Shannon Zurevinski [sup.3], Sandra Kamo [sup.4], Rongqing Zhang [sup.5], Yu Zhang [sup.6], Qiaofen Liu [...]

SETTING: Alberta is a prairie province located in western Canada, with a population of approximately 4.3 million. In 2016, 363 Albertans died from apparent drug overdoses related to fentanyl, an opioid 50-100 times more toxic than morphine. This surpassed the number of deaths from motor vehicle collisions and homicides combined. INTERVENTION: Naloxone is a safe, effective, opioid antagonist that may quickly reverse an opioid overdose. In July 2015, a committee of communitybased harm reduction programs in Alberta implemented a geographically restricted take- home naloxone (THN) program. The successes and limitations of this program demonstrated the need for an expanded, multi-sectoral, multi- jurisdictional response. The provincial health authority, Alberta Health Services (AHS), used previously established incident command system processes to coordinate implementation of a provincial THN program. OUTCOMES: Alberta's provincial THN program was implemented on December 23, 2015. This collaborative program resulted in a coordinated response across jurisdictional levels with wide geographical reach. Between December 2015 and December 2016, 953 locations, including many community pharmacies, registered to dispense THN kits, 9572 kits were distributed, and 472 reversals were reported. The provincial supply of THN kits more than tripled from 3000 to 10 000. IMPLICATIONS: Alberta was uniquely poised to deliver a large, province-wide, multi-sectoral and multi-jurisdictional THN program as part of a comprehensive response to increasing opioid-related morbidity and mortality. The speed at which AHS was able to roll out the program was made possible by work done previously and the willingness of multiple jurisdictions to work together to build on and expand the program. KEY WORDS: Fentanyl; take-home naloxone; harm reduction; opioid overdose La traduction du resume se trouve a la fin de l'article. LIEU : L'Alberta, une province des Prairies de l'Ouest canadien, a une population d'environ 4,3 millions d'habitants. En 2016, 363 Albertains sont decedes de surdoses apparentes de fentanyl, un opioide 50 a 100 fois plus toxique que la morphine. Ce chiffre a depasse le nombre de deces par collision entre vehicules automobiles et de deces par homicide combines. INTERVENTION : La naloxone est un antagoniste opio'i'de sur et efficace qui peut rapidement neutraliser une surdose d'opio'i'des. En juillet 2015, un comite d'intervenants de programmes communautaires de reduction des mefaits de l'Alberta a mis en reuvre dans une zone geographiquement restreinte un programme de << trousses maison de naloxone >> (TMN). Les reussites et les contraintes de ce programme ont demontre le besoin d'une intervention elargie, multisectorielle et intergouvernementale. L'autorite sanitaire provinciale, Alberta Health Services (AHS), s'est servie des processus etablis du systeme de commandement en cas d'incident pour coordonner la mise en reuvre d'un programme de TMN provincial. RESULTATS : Le programme de TMN provincial de l'Alberta a ete mis en reuvre le 23 decembre 2015. Ce programme concerte a coordonne une intervention intergouvernementale de grande portee geographique. Entre decembre 2015 et decembre 2016, 953 etablissements, dont de nombreuses pharmacies communautaires, se sont inscrits au registre pour pouvoir dispenser des TMN, 9 572 trousses ont ete distribuees, et 472 surdoses neutralisees ont ete declarees. Les approvisionnements provinciaux en TMN ont plus que triple, passant de 3 000 a 10 000. CONSEQUENCES : L'Alberta etait singulierement bien placee pour offrir un vaste programme de TMN multisectoriel et intergouvernemental a l'echelle de la province dans le cadre d'une intervention globale face aux hausses de la morbidite et de la mortalite liees aux opioides. La vitesse a laquelle AHS a pu deployer le programme s'explique par le travail effectue anterieurement et par la volonte de plusieurs spheres de competence de travailler ensemble pour renforcer et developper le programme. MOTS CLES : fentanyl; trousse maison de naloxone; reduction des dommages; surdose d'opioides, Morbidity and mortality related to opioid overdoses are increasing worldwide. (1) Fentanyl is an opioid up to 100 times more toxic than morphine. (2) It is used therapeutically for pain [...]

OBJECTIVES: To investigate patterns of survival among brain cancer patients in Canada. METHODS: Canadian Cancer Registry data were obtained for all patients with first-ever primary malignant brain tumours diagnosed between 1992 and 2008 (n = 38,095). Follow-up ended with patient death or December 31,2008, whichever occurred first. Crude Kaplan-Meier estimates were calculated at one, two and five years post-diagnosis. Cox proportional hazard models were used to obtain adjusted hazard ratios by region for major histology types. A time-specific generalized linear model was used to obtain 5-year survival estimates for specific age group, sex and region for major histology types. RESULTS: The overall five-year survival rate was 27%. No significant difference in survival rate over time is observed. The highest 5-year survival rate was 65% (95% CI: 62.5%-67.4%) for oligodendrogliomas and the lowest was 4.0% (95% CI: 3.7%-4.3%) for glioblastomas. Compared to Ontario, the adjusted 5-year glioblastoma survival estimates were lower in British Columbia, Alberta and the Prairie provinces (Manitoba and Saskatchewan), while the survival estimates were lower in all other regions for diffuse astrocytoma, and lower in Manitoba and Saskatchewan for anaplastic astrocytomas. Estimates were significantly higher for oligodendrogliomas in Alberta, and for anaplastic oligodendrogliomas in Alberta and Quebec (p < 0.05). CONCLUSION: These data are consistent with previous literature in observing higher survival rates at younger ages, in female patients and for tumours with mixed oligo components. There is a need to further explore the underlying reasons for the observed variation in survival rates by region in an effort to improve the prognosis of brain cancer in the Canadian patient population. KEY WORDS: Brain neoplasms; survival rate; Canada OBJECTIFS: Etudier les profils de survie des patients atteints d'un cancer du cerveau au Canada. METHODE: Nous avons obtenu les donnees du Registre canadien du cancer sur tous les patients atteints d'une premiere tumeur cerebrale maligne primaire diagnostiquee entre 1992 et 2008 (n = 38 095). Le suivi s'est termine au deces des patients ou au 31 decembre 2008, selon la premiere des deux eventualites. Des estimations de Kaplan-Meier brutes ont ete calculees a un, deux et cinq ans apres le diagnostic. Nous avons utilise des modeles des risques proportionnels de Cox pour obtenir des coefficients de danger ajustes par region pour les grands types histologiques, respectivement. Un modele lineaire generalise dans le temps a servi a obtenir des estimations de survie apres 5 ans par groupe d'age, par sexe et par region pour les grands types histologiques. RESULTATS: Le taux de survie global etait de 27%. On n'observe aucun ecart significatif dans le taux de survie au fil du temps. Le taux de survie le plus eleve apres 5 ans etait de 65% (IC de 95%: 62,5%-67,4%) pour les oligodendrogliomes; le plus faible etait de 4% (IC de 95%: 3,7%-4,3%) pour les glioblastomes. Comparativement a l'Ontario, les estimations ajustees de survie au glioblastome apres 5 ans etaient inferieures en Colombie-Britannique, en Alberta et dans les provinces des Prairies (Manitoba et Saskatchewan), tandis que les estimations de survie etaient inferieures dans toutes les autres regions pour les astrocytomes diffus, et inferieures au Manitoba et en Saskatchewan pour les astrocytomes anaplasiques. Les estimations etaient sensiblement plus elevees pour les oligodendrogliomes en Alberta, et pour les oligodendrogliomes anaplasiques en Alberta et au Quebec (p < 0,05). CONCLUSION: Ces donnees sont conformes a celles d'etudes anterieures ou l'on a observe des taux de survie superieurs chez les jeunes patients, chez les femmes et pour les tumeurs mixtes (oligo-astrocytomes). Il faudrait pousser la recherche sur les raisons sous-jacentes de la variation observee des taux de survie par region afin d'ameliorer le pronostic du cancer du cerveau dans la population de patients au Canada. MOTS CLES: tumeurs du cerveau; taux de survie; Canada La traduction du resume se trouve a la fin de l'article. Can J Public Health 2016;107(1):e37-e42 doi: 10.17269/CJPH.107.5209, There is little information available on brain tumour incidence and survival among the Canadian population. (1,2) Available information provides an overall estimate of brain cancer survival without an assessment of [...]

The expansion of woody species into grasslands has altered community structure and ecosystem function of grasslands worldwide. In tallgrass prairie of the Central Great Plains, USA, decreased fire frequency and intensity have increased the cover and abundance of woody species. In particular, clonal shrub cover has increased at accelerated rates due to vegetative reproduction and resprouting after disturbance. We measured the intra-clonal stem demography and relative growth rates (estimated change in woody biomass) of the shrub Cornus drummondii in response to fire frequency (4 vs 20 year burn intervals) and simulated browsing during the 2018 and 2019 growing seasons at Konza Prairie Biological Station (Manhattan, Kansas). Overall, infrequent fire (4 year burn interval) increased intra-clonal stem relative growth rates and shrub relative growth rates. Intra-clonal stem relative growth rates were reduced in unbrowsed clones in 2018 due to drought and simulated browsing reduced intra-clonal stem relative growth rates in 2019. Additionally, simulated browsing nearly eliminated flower production within clones but did not affect intra-clonal stem mortality or recruitment within a growing season. Fire in conjunction with simulated browsing reduced estimated relative growth rates for entire shrub clones. Browsed shrubs that experienced prescribed fire in 2017 had reduced intra-clonal stem densities compared to unbrowsed shrubs and stem densities of browsed shrubs did not recover in 2018 or 2019. These results illustrate that infrequent fire alone promotes the expansion of clonal shrubs in tallgrass prairie and multiple interacting disturbances (e.g., fire and browsing) are required to control the spread of clonal shrubs into grasslands., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduced ecosystem engineers are expected to have extensive ecological impacts on a broad range of resident biota by altering the physical-chemical structure of ecosystems. Livestock that are potentially important introduced ecosystem engineers in grassland systems could create and/or modify habitats for native plant-dwelling insects. Yet, there is little knowledge of how insects respond to engineering effects of introduced livestock. To bridge this gap, we tested how domestic sheep affects the behavior and abundance of a native grasshopper Euchorthippus unicolor at both low (11.8 ± 0.4 plant species per plot) and high (19.8 ± 0.5 plant species per plot) diversity sites. Results found grasshoppers shifted their resting and feeding locations from the upper to the intermediate or low layers of vegetation, and fed on more plants species following livestock engineering effects. In the low plant diversity habitats, grazing caused grasshoppers to increase switching frequency, spend more time searching for host plants, and reduce time spent feeding, but had opposite effects on all the three behaviors in the high-diversity habitats. Moreover, grazing engineering effects on behavioral changes of grasshoppers were potentially related to their abundance. Overall, this study highlights native insect species' behavior and abundance in responses to introduced ecological engineers, and suggests that ecosystem engineers of non-native species have strong and important impacts extending beyond their often most obvious and frequently documented direct ecological effects.

An epidemiological study of gastrointestinal nematodes was carried out in naturally infected goats in the North West of Algeria. Coprological analyses were performed for 2 years from January 2014 to December 2015.Examination of 1591 goat samples revealed an overall prevalence of parasite eggs in feces of 96%; the values were very similar in both years at 97% in 2014 and 94.96% in 2015. Five types of nematode eggs were identified: strongyle (95.5%), Nematodirus spp. (19.4%), Marshallagia spp. (3.9%), Trichuris spp. (0.6%), and Skrjabinema spp. (2%).Also, fecal cultures showed the presence of Teladorsagia spp. (56%), Trichostrongylus spp. (20%), Chabertia spp. (10%), Haemonchus spp. (9%), and Oesophagostomum spp. (5%).Season, age, type of grazing, and area affected the epidemiology of gastrointestinal nematodes of goats. The season did not influence the prevalence observed in the 2 years, since no significant differences between the four seasons were observed. On the other hand, egg production was highest in winter and spring. The level of infection decreased with the animal's age. There were no significant differences between the prevalence in animals on irrigated and non-irrigated pastures, but there were differences in egg excretion. Additionally, no significant difference was observed between the coastal (Oran) and lowland (Mascara) regions in the prevalence or in average egg excretion.

Recent studies on handwriting production and neuropsychological data have suggested that orthographic representations are multilevel structures that encode information on letter identity and order, but also on intermediate-grained processing units such as syllables and morphemes. This study on handwriting production examined whether orthographic representations also include a graphemic-processing level. French adults wrote words containing an embedded one-, two-, or three-letter grapheme (e.g., A in CLAVIER, AI in PRAIRIE, AIN in PLAINTE) on a digitizer. The results for letter duration revealed that the timing of movement processing depends on grapheme length (e.g., the duration Of A for one-letter graphemes was shorter than that for two-letter graphemes, which, in turn, was shorter than that for three-letter graphemes). Two- and three-letter graphemes start to be processed before we start to write them. The results therefore revealed that orthographic representations also encode information on grapheme complexity. doi: 10.3758/MC.38.6.762

Byline: Andrew Grundstein (1) Abstract: This paper uses a modified form of Thornthwaite's moisture index to better quantify climate variability by integrating the effects of temperature and precipitation. Using the moisture index, trends were evaluated over the last 112 years (1895--2006), when unique changes in temperature and precipitation have been documented to have occurred. In addition, data on potential evapotranspiration and the moisture index were used to investigate changing climate and vegetation regions. The results show that the eastern half of the country has been getting wetter, even as temperatures have continued to increase in many areas. In particular, conditions have become wetter in the South, Northeast, and East North Central regions. The changing climate is illustrated by computing climate and vegetation regions for three 30-year periods (1910--1939, 1940--1969, and 1970--1999). Climate regions based on the moisture index show an expansion of the Humid region (where precipitation vastly exceeds climatic demands for water) across the East as well as a westward shift in the zero moisture index line. In terms of vegetation zones, the most dramatic change occurs across the Midwestern prairie peninsula where the wetter conditions lead to a westward expansion of conditions favorable for oak--hickory--pine vegetation. Author Affiliation: (1) Climatology Research Laboratory, Department of Geography, University of Georgia, Athens, GA, 30602-2502, USA Article History: Registration Date: 24/06/2008 Received Date: 24/03/2006 Accepted Date: 12/05/2008 Online Date: 22/08/2008

Byline: Roger Feldman (1), Jennifer Schultz (2) Abstract: This paper addresses the following question: Why do consumers demand guaranteed renewability in health insurance? The answer to this question has important implications for the ability of competitive health insurance markets to provide affordable health insurance for people with chronic illness. The approach is novel. Empirical studies show that guaranteed renewability exists in health and life insurance. In the health insurance setting, these findings imply that consumers' preferences for low premiums and quality do not depend on their health status. Then consumer preference data collected from a survey of approximately 1,000 single employees in 19 Minneapolis-area companies are examined to determine if healthy and unhealthy consumers have similar preferences for low premiums and quality. It is found that employees' preference ratings for the importance of low premiums and aspects of provider and service quality are not related to their health status. These findings imply that health-related diversity of preferences is not likely to cause the employees in this study to select different health insurance plans. However, there is evidence of diverse preferences related to employee demographics such as income, education, and gender. Author Affiliation: (1) Division of Health Services Research and Policy, University of Minnesota, Mayo Mail Code 729, 420 Delaware St., SE, Minneapolis, MN, 55455, USA (2) Ingenix Corporation in Eden Prairie, MN, USA Article History: Registration Date: 01/10/2004

Available meteorological, dendrochronological and glacier area change data are reviewed for the central Canadian Rockies. Limited glacier inventory studies indicate a loss of ca 25% of glacier area (greater for smaller glaciers) since the Little Ice Age maximum 130-150 years ago. The few available long climate records are from widely spaced, valley floor sites, well below treeline. Available gridded or regional climate data sets similarly contain no high elevation sites. The five long (75 yr) station records contain a strong common signal but show differences in the relative amplitude and timing of temperature variations indicating links to either prairie or pacific stations. However the station network is too sparse to define the spatial extent of these patterns. Tree-ring chronologies from a network of Picea engelmannii (21), Larix lyallii (17) and Pinus albicaulis (2) treeline sites are presented and reviewed. Residual chronologies show stronger intercorrelation than standard chronologies and the larix chronologies are more highly correlated than picea, probably because of the narrower range of sites sampled. Many standard chronologies show a strong common regional signal of above average growth in the late 17th, late 18th and mid-20th centuries and reduced growth in the early 17th, early 18th and for most of the 19th centuries. However, examination of individual chronologies shows strong local or sub-regional divergence from this pattern that reflects smaller scale climate or non-climatic influences. Differences in the density and location of sites between the climate and tree-ring networks will create problems in resolving climate variation at the sub-regional scale.

The potential equilibrium response of Canadian vegetation under two doubled-CO(sub 2) climatic scenarios was investigated at three levels in the vegetation mosaic using the rule-based, Canadian Climate-Vegetation Model (CCVM) and climatic response surfaces. The climatic parameters employed as model drivers (i.e., degree-days, minimum temperature, snowpack, actual evapotranspiration, and soil moisture deficit) have a more direct influence on the distribution of vegetation than those commonly used in equilibrium models. Under both scenarios, CCVM predicted reductions in the extent of the tundra and subarctic woodland formations, a northward shift and some expansion in the distributions of boreal and the temperate forest, and an expansion of the dry woodland and prairie formations that was especially pronounced under one of the scenarios. Results of the response surface analysis suggest the potential for significant changes in the probability of dominance for eight boreal tree species. A dissimilarity coefficient was used to identify forest-types under the future climatic scenarios that were analogous to boreal forest-types derived from cluster analysis of the current probabilities of species dominance. All of the current forest-types persisted under the doubled-CO(sub 2) scenarios, but 'no-analog' areas were also identified within which an empirically derived threshold of the distance coefficient was exceeded. Maps showing the highest level in the vegetation hierarchy where change was predicted suggest the relative impact of the response under the two climatic scenarios.

Newborn wild house mice (Mus musculus) were fostered upon maternal conspecifics, prairie deer mice (Peromyscus maniculatus bairdi) or laboratory rats (Rattus norvegicus). Male subjects were weaned into individual cages, in which they remained until testing commenced. At 35 days of age, subjects were given a four-choice test in which they had the opportunity to investigate tunnels scented with clean wood chips or with chips soiled by an adult male conspecific, deer mouse or rat. Compared to the Mus-nursed and Peromyscus-nursed mice, Rattus-nursed mice were more active during the test and less reluctant to investigate the Rattus-scented tunnel. These results were replicated in a two-choice test (Mus- vs. Rattus-scented tunnels) that included a group of mice fostered onto conspecifics, but with Rattus scents present in the maternity cage throughout the nursing period. Early exposure to the scent of Rattus had no significant effects on the responses of Mus-nursed mice to the scent of Rattus.

Kidney support therapy (KST), previously referred to as Renal Replacement Therapy, is utilized to treat children and adults with severe acute kidney injury (AKI), fluid overload, inborn errors of metabolism, and kidney failure. Several forms of KST are available including peritoneal dialysis (PD), intermittent hemodialysis (iHD), and continuous kidney support therapy (CKST). Traditionally, extracorporeal KST (CKST and iHD) in neonates has had unique challenges related to small patient size, lack of neonatal-specific devices, and risk of hemodynamic instability due to large extracorporeal circuit volume relative to patient total blood volume. Thus, PD has been the most commonly used modality in infants, followed by CKST and iHD. In recent years, CKST machines designed for small children and novel filters with smaller extracorporeal circuit volumes have emerged and are being used in many centers to provide neonatal KST for toxin removal and to achieve fluid and electrolyte homeostasis, increasing the options available for this unique and vulnerable group. These new treatment options create a dramatic paradigm shift with recalibration of the benefit: risk equation. Renewed focus on the infrastructure required to deliver neonatal KST safely and effectively is essential, especially in programs/units that do not traditionally provide KST to neonates. Building and implementing a neonatal KST program requires an expert multidisciplinary team with strong institutional support. In this review, we first describe the available neonatal KST modalities including newer neonatal and infant-specific platforms. Then, we describe the steps needed to develop and sustain a neonatal KST team, including recommendations for provider and nursing staff training. Finally, we describe how quality improvement initiatives can be integrated into programs., Author(s): Tahagod H. Mohamed [sup.1] [sup.2] , Jolyn Morgan [sup.3] , Theresa A. Mottes [sup.4] , David Askenazi [sup.5] , Jennifer G. Jetton [sup.6] , Shina Menon [sup.7] Author Affiliations: [...]

Compressed sensing (CS) ensures the recovery of sparse vectors from a number of randomized measurements proportional to their sparsity. The initial theory considers discretized domains, and the randomness makes the physical positions of the grid nodes irrelevant. Most imaging devices, however, operate over some continuous physical domain, and it makes sense to consider Dirac masses with arbitrary positions. In this article, we consider such a continuous setup and analyze the performance of the BLASSO algorithm, which is the continuous extension of the celebrated LASSO [Formula omitted] regularization method. This approach is appealing from a numerical perspective because it avoids to discretize the domain of interest. Previous works considered translation-invariant measurements, such as randomized Fourier coefficients, in which it makes clear that the discrete theory should be extended by imposing a minimum distance separation constraint (often called 'Rayleigh limit') between the Diracs. These prior works, however, rule out many domains and sensing operators of interest, which are not translation invariant. This includes, for instance, Laplace measurements over the positive reals and Gaussian mixture models over the mean-covariance space. Our theoretical advances crucially rely on the introduction of a canonical metric associated with the measurement operator, which is the so-called Fisher geodesic distance. In the case of Fourier measurements, one recovers the Euclidean metric, but this metric can cope with arbitrary (possibly non-translation invariant) domains. Furthermore, it is naturally invariant under joint reparameterization of both the sensing operator and the Dirac locations. Our second and main contribution shows that if the Fisher distance between spikes is larger than a Rayleigh separation constant, then the BLASSO recovers in a stable way a stream of Diracs, provided that the number of measurements is proportional (up to log factors) to the number of Diracs. We measure the stability using an optimal transport distance constructed on top of the Fisher geodesic distance. Our result is (up to log factor) sharp and does not require any randomness assumption on the amplitudes of the underlying measure. Our proof technique relies on an infinite-dimensional extension of the so-called golfing scheme which operates over the space of measures and is of general interest., Author(s): Clarice Poon [sup.1] , Nicolas Keriven [sup.2] , Gabriel Peyré [sup.3] Author Affiliations: (1) grid.7340.0, 0000 0001 2162 1699, Department of Mathematical Sciences, University of Bath, , Bath, UK [...]