17 research outputs found
Extra-tall stubble can increase crop yield in the semiarid Canadian prairie
No full text Cutforth, H., McConkey, B., Angadi, S. and Judiesch, D. 2011. Extra-tall stubble can increase crop yield in the semiarid Canadian prairie. Can. J. Plant Sci. 91: 783–785. Previous research in the semiarid prairie showed that crop yields increased as the height of standing stubble increased to 30 cm. Recent technology permits seeding into higher standing stubble. A 3-yr (2001–2003) study was conducted at Swift Current, SK, to determine how seeding canola, pulse, and wheat into cultivated, short (about 15 cm high), tall (about 30 cm high), and extra-tall (about 45 cm high) standing stubble affected crop yield. Crop yield and the overall average water use efficiency increased linearly as stubble height increased to 45 cm. Water use was independent of stubble height. </jats:p
Comparative forage yield, water use, and water use efficiency of alfalfa, crested wheatgrass and spring wheat in a semiarid climate in southern Saskatchewan
No full text Crested wheatgrass (Agropyron cristatum L. Gaertn.) and alfalfa (Medicago sativa L.) are introduced forage species used for hay and grazing by cattle across western Canada. These species are well adapted to the semiarid region but their long-term responses to water stress have not been previously compared. Two alfalfa cultivars with contrasting root morphology (tap-rooted vs. creeping-rooted) and two crested wheatgrass (CWG) cultivars with different ploidy level (diploid vs. tetraploid) were compared with continuously cropped spring wheat (Triticum aestivum L.) for 6 yr at a semiarid location in western Canada. Soil water depletion, forage yield, water use efficiency, leaf water potential, osmotic potential and turgor were compared. There were no consistent differences between cultivars within alfalfa or CWG for variables measured. However, these two species exhibit different water stress response strategies. Leaf water potential of CWG was lower during midday stress period than that of alfalfa or wheat. Alfalfa apparently had greater capacity to osmotically adjust to avoid midday water stress and maintain higher turgor. Soil water use patterns changed as the stands aged. In the initial years of the trial, forage crops used soil water from upper layers of the profile. In later years, soil water was depleted down to 3 m by alfalfa and to 2 m by crested wheatgrass. Alfalfa was able to deplete soil water to lower concentrations than crested wheatgrass or wheat. Soil water depletion by wheat during the non-active growth season (after harvest to fall freeze-up) was much less than for CWG or alfalfa as expected for annual vs. perennial crops. As a result, more soil water was available to wheat during its active growth period. In the last 3 yr, the three species depleted all available soil water. Forage yield responses also changed over time. In the initial 3 yr, crested wheatgrass yielded as much as or more than alfalfa. For the last 3 yr of the experiment, alfalfa yielded more forage than crested wheatgrass. Forage crops deplete much more soil water during periods of aboveground growth dormancy than wheat. Water use efficiency of crested wheatgrass declined with stand age compared with fertilized continuous spring wheat. Alfalfa exhibited deep soil water extraction and apparent osmotic adjustment in response to water stress while CWG exhibited tolerance of low water potential during stress. Key words: forage yield, soil water, water potential, water use, water use efficiency, drought </jats:p
Evaluating physical therapy students' knowledge of and adherence to the ambassador low back pain guideline
No full textPurpose: To examine a process for evaluating physiotherapy (PT) students' knowledge of and adherence to the Ambassador Low Back Pain (LBP) guideline using vignettes. Methods: The study used a cross-sectional survey design. Participants were PT students who had received information related to the guideline as part of their curriculum. Primary measures were responses to questions about the management of four clinical vignettes. Adherence to guideline recommendations was measured by comparing participant scores to a guideline-based set of responses from a physiotherapist involved in developing the Ambassador guideline, which was considered a criterion standard. Results: A total of 74 respondents provided complete data, for a response rate of 89percent; 65 (88percent) reported no knowledge of the guideline. Overall consistency with the criterion standard was high (70percent). Respondents demonstrated high adherence when identifying red flags and deciding whether to refer to another provider. Conclusion: Despite known exposure, knowledge of the guideline was low in this sample of Canadian PT students. Nevertheless, in several key areas, unconscious adherence was high relative to the guidelinebased criterion standard. With minor modifications, the vignettes are suitable for evaluating the Ambassador LBP guidelines in a larger study.Bekkering GE, 2005, QUAL SAF HEALTH CARE, V14, P107, DOI 10.1136-qshc.2003.009357; Bekkering GE, 2003, PHYSIOTHERAPY, V89, P82, DOI DOI 10.1016-S0031-9406(05)60579-2; Bishop Paul B, 2003, Spine J, V3, P442, DOI 10.1016-S1529-9430(03)00152-9; Bishop Paul B, 2006, Spine J, V6, P282, DOI 10.1016-j.spinee.2005.10.008; Cassidy JD, 1998, SPINE, V23, P1860, DOI 10.1097-00007632-199809010-00012; Cutforth G, 2011, PHYSIOTHER CAN, V63, P278, DOI 10.3138-ptc.2009-39P; Di Iorio D, 2000, ARCH FAM MED, V9, P1015, DOI 10.1001-archfami.9.10.1015; Domenech J, 2011, PAIN, V152, P2557, DOI 10.1016-j.pain.2011.07.023; Foster NE, 2011, PHYS THER, V91, P790, DOI 10.2522-ptj.20100326; George SZ, 2011, BMC MED, V9, DOI 10.1186-1741-7015-9-128; Gould D, 1996, J CLIN NURS, V5, P207, DOI 10.1111-j.1365-2702.1996.tb00253.x; GRIMSHAW J, KNOWLEDGE SYNTHESIS; Grol R, 2003, LANCET, V362, P1225, DOI 10.1016-S0140-6736(03)14546-1; Gross DP, 2006, SPINE, V31, P2142, DOI 10.1097-01.brs.0000231771.14965.e4; Gross DP, 2009, DISABIL REHABIL, V31, P871, DOI [10.1080-01443610802355965, 10.1080-014413610802355965]; Harman K, 2009, PHYSIOTH CAN, V61, P88, DOI 10.3138-physio.61.2.88; Harstall C, 2011, J EVAL CLIN PRACT, V17, P693, DOI 10.1111-j.1365-2753.2010.01420.x; Hay EM, 2008, BMC MUSCULOSKEL DIS, V9, DOI 10.1186-1471-2474-9-58; Hayden JA, 2009, J CLIN EPIDEMIOL, V62, P781, DOI 10.1016-j.jclinepi.2008.09.004; Hayden JA, 2010, BEST PRACT RES CL RH, V24, P167, DOI 10.1016-j.berh.2009.12.005; Hill JC, 2011, LANCET, V378, P1560, DOI 10.1016-S0140-6736(11)60937-9; Hill JC, 2010, EUR J PAIN, V14, P83, DOI 10.1016-j.ejpain.2009.01.003; Hockings RL, 2008, SPINE, V33, pE494, DOI 10.1097-BRS.0b013e31817ba3bb; Ikezawa Y, 2010, J OCCUP REHABIL, V20, P367, DOI 10.1007-s10926-010-9230-z; Institute of Health Economics, 2009, GUID EV INF PRIM CAR; Koes BW, 2010, EUR SPINE J, V19, P2075, DOI 10.1007-s00586-010-1502-y; Main CJ, 2011, PHYS THER, V91, P820, DOI 10.2522-ptj.20110060; Peabody JW, 2000, JAMA-J AM MED ASSOC, V283, P1715, DOI 10.1001-jama.283.13.1715; Peabody JW, 2004, ANN INTERN MED, V141, P771; Poitras S, 2007, J EVAL CLIN PRACT, V13, P412, DOI 10.1111-j.1365-2753.2006.00725.x; Poitras S, 2012, SPINE, V37, P1252, DOI 10.1097-BRS.0b013e31824b6adf; Poitras S, 2005, PHYS THER, V85, P1168; Portney LG, 2009, FDN CLIN RES APPL PR; Rainville J, 2000, SPINE, V25, P2210, DOI 10.1097-00007632-200009010-00012; RASHIQ S, 2006, BMC MED EDUC, V6, P1; Rutten G, 2009, J CLIN EPIDEMIOL, V62, P167, DOI 10.1016-j.jclinepi.2008.04.004; Rutten GM, 2010, PHYS THER, V90, P1111, DOI 10.2522-ptj.20090173; Rutten GMJ, 2006, J EVAL CLIN PRACT, V12, P491, DOI 10.1111-j.1365-2753.2006.00699.x; Schreiber J, 2005, INTERNET J ALLIED HE, V3, P1; Shah R, 2010, OPHTHAL PHYSL OPT, V30, P209, DOI 10.1111-j.1475-1313.2010.00713.x; Turner Patricia A., 1999, Physiotherapy Theory and Practice, V15, P235, DOI 10.1080-095939899307649; van Tulder MW, 2004, SPINE, V29, pE357, DOI 10.1097-01.brs.0000137056.64166.51; Webster BS, 2005, J GEN INTERN MED, V20, P1132, DOI 10.1111-j.1525-1497.2005.0230.x11
Water stress, sap flow and transpiration for medium and highly drought resistant poplars grown in the semiarid Canadian prairie
No full textSap flow was measured to determine transpiration rates for CanAm and Walker poplars grown in the semiarid Canadian prairie. CanAm poplars had higher sap flow rates and were better able to supply water to actively growing regions for all water availabilities (well-watered to drought). CanAm poplars were better able to survive drought.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Long-term changes in the frost-free season on the Canadian prairies
No full text The climate of the prairies has warmed over the past century, especially during late winter and early spring. Some regions of the prairies have warmed faster than others. Climate change has been documented to affect living systems in North America, such as promoting earlier phenological development and longer growing seasons. We examined weather records gathered at several long-term weather-recording sites across the agricultural regions of the Canadian prairies for evidence of trends in last spring frosts, first fall frosts, and frost-free durations. During the latter half of the 20th century, the trends were towards earlier last spring frost dates and towards longer frost-free seasons in the agricultural regions of the Canadian prairies. Across most of the prairies the trends towards later first fall frost dates were smaller and generally not significant. The largest changes have occurred in the central and northern agricultural regions of Alberta, whereas the least change occurred over much of southern Alberta and in southern Manitoba. Key words: Last spring and first fall frost dates, frost-free season, agroclimatic indices, climate change, Canadian prairies </jats:p
Strategies for reducing the carbon footprint of field crops for semiarid areas. A review
No full textVertical distribution profiles and temporal growth patterns of roots in selected oilseeds, pulses and spring wheat
No full text
Knowledge of rooting systems and their vertical distribution in the soil profile for field crops is required for designing crop rotation systems that allow for effective use of soil water and nutrients. This study determined the vertical distribution in the upper 100 cm of the soil profile and the temporal growth patterns of roots for three pulses (Cicer arietinum L. chickpea, Pisum sativum L. dry pea, and Lens culinaris Medik. lentil) and three oilseeds (napus canola, juncea mustard, and Linum usitatissimum flax) and spring wheat (Triticum aestivum L.). Crops were grown in 150-mm-diameter, 1-m-long lysimeters under low- (rainfall only) and high- (rainfall + irrigation) water availabilities in a 2-year (2006–07) field study, in Swift Current, Canada. Root volumes increased significantly from the seedling stage, reached the maximum at the late-flowering, and declined to maturity; this temporal growth pattern was independent with water availability. On average, ~44% of the root volume was in the top 20-cm soil layer, 70% in the top 40 cm, and 90% in the top 60 cm. About 5% of the roots in pulse crops were located below 60 cm in depth, significantly less than the 12% for wheat, 13% for mustard, and 18% for canola. Under low-water conditions, Brassica oilseeds had greater root volume (33 mm3 cm–3) than wheat (27 mm3 cm–3), but under high-water conditions, root volumes were 27 mm3 cm–3 for the Brassicas and 32 mm3 cm–3 for wheat. Pulses had greatest root volumes under both low- (40 mm3 cm–3) and high- (42 mm3 cm–3) water conditions, with largest root diameters among crops evaluated, whereas flax the smallest. Rotating the shallower but larger diameter, thicker-rooting pulses with deeper but smaller diameter, thinner-rooting oilseeds or wheat may increase water- and nutrient-use efficiency at the system level.
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Increased Excitatory Synaptic Transmission of Dentate Granule Neurons in Mice Lacking PSD-95-Interacting Adhesion Molecule Neph2/Kirrel3 during the Early Postnatal Period
No full textCopy number variants and point mutations of NEPH2 (also called KIRREL3) gene encoding an immunoglobulin (Ig) superfamily adhesion molecule have been linked to autism spectrum disorders, intellectual disability and neurocognitive delay associated with Jacobsen syndrome, but the physiological roles of Neph2 in the mammalian brain remain largely unknown. Neph2 is highly expressed in the dentate granule (DG) neurons of the hippocampus and is localized in both dendrites and axons. It was recently shown that Neph2 is required for the formation of mossy fiber filopodia, the axon terminal structure of DG neurons forming synapses with GABAergic neurons of CA3. In contrast, however, it is unknown whether Neph2 also has any roles in the postsynaptic compartments of DG neurons. We here report that, through its C-terminal PDZ domain-binding motif, Neph2 directly interacts with postsynaptic density (PSD)-95, an abundant excitatory postsynaptic scaffolding protein. Moreover, Neph2 protein is detected in the brain PSD fraction and interacts with PSD-95 in synaptosomal lysates. Functionally, loss of Neph2 in mice leads to age-specific defects in the synaptic connectivity of DG neurons. Specifically, Neph2−/− mice show significantly increased spontaneous excitatory synaptic events in DG neurons at postnatal week 2 when the endogenous Neph2 protein expression peaks, but show normal excitatory synaptic transmission at postnatal week 3. The evoked excitatory synaptic transmission and synaptic plasticity of medial perforant pathway (MPP)-DG synapses are also normal in Neph2−/− mice at postnatal week 3, further confirming the age-specific synaptic defects. Together, our results provide some evidence for the postsynaptic function of Neph2 in DG neurons during the early postnatal period, which might be implicated in neurodevelopmental and cognitive disorders caused by NEPH2 mutations.
Copyright © 2017 Roh, Choi, Cho, Choi, Park, Cutforth, Chung, Park, Lee, Kim, Lee,
Mo, Rhee, Kim, Ko, Choi, Bae, Shen, Kim and Han. This is an open-access article
distributed under the terms of the Creative Commons Attribution License (CC BY).
The use, distribution and reproduction in other forums is permitted, provided the
original author(s) or licensor are credited and that the original publication in this
journal is cited, in accordance with accepted academic practice. No use, distribution
or reproduction is permitted which does not comply with these terms.
© 2017 Roh, Choi, Cho, Choi, Park, Cutforth, Chung, Park, Lee, Kim, Lee,
Mo, Rhee, Kim, Ko, Choi, Bae, Shen, Kim and Han. This is an open-access article
distributed under the terms of the Creative Commons Attribution License (CC BY).
The use, distribution and reproduction in other forums is permitted, provided the
original author(s) or licensor are credited and that the original publication in this
journal is cited, in accordance with accepted academic practice. No use, distribution
or reproduction is permitted which does not comply with these terms.
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