51 research outputs found
Architecture of a mammalian glomerular domain revealed by novel volume electroporation using nanoengineered microelectrodes
No full textDense microcircuit reconstruction techniques have begun to provide ultrafine insight into the architecture of small-scale networks. However, identifying the totality of cells belonging to such neuronal modules, the “inputs” and “outputs,” remains a major challenge. Here, we present the development of nanoengineered electroporation microelectrodes (NEMs) for comprehensive manipulation of a substantial volume of neuronal tissue. Combining finite element modeling and focused ion beam milling, NEMs permit substantially higher stimulation intensities compared to conventional glass capillaries, allowing for larger volumes configurable to the geometry of the target circuit. We apply NEMs to achieve near-complete labeling of the neuronal network associated with a genetically identified olfactory glomerulus. This allows us to detect sparse higher-order features of the wiring architecture that are inaccessible to statistical labeling approaches. Thus, NEM labeling provides crucial complementary information to dense circuit reconstruction techniques. Relying solely on targeting an electrode to the region of interest and passive biophysical properties largely common across cell types, this can easily be employed anywhere in the CNS
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
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.
Frontiers1321sciescopu
Temperature response function for leaf appearance rate in wheat and corn
No full text The ability to predict leaf appearance would enhance our capability of modeling plant development and the rate of leaf area expansion. Many crop models use the constant thermal time for successive leaf tip appearance (which is often termed a phyllochron) as one model parameter to predict total number of leaves and date of anthesis. However, many researchers have found that phyllochron is not constant, but is dependent upon environment. The problem could be related to the simplified assumption that the daily leaf appearance rate is linearly related to temperature (and hence, phyllochron is constant, independent of temperature). In reality, the temperature response function for the development of a biological system is nonlinear. Thus, we fitted daily leaf appearance rate–temperature relationships obtained from growth room studies for both wheat (Triticum aestivum) and corn (Zea mays L.) to a nonlinear beta function with 0 °C as the base temperature and 42 °C as the upper critical temperature. The function described the relationships very well over the full range of temperatures for plant development. Other variables that are used to describe the duration and rate of leaf appearance, such as calendar days, phyllochron, and thermal rate of leaf appearance, are related to the daily leaf appearance rate, eliminating the need to develop various mathematical functions to independently describe the response of these variables to temperature. Because of the nonlinear nature of the temperature response function, we demonstrated that more accurate determinations of daily leaf appearance rates can be achieved by calculating rates over relatively short periods (i.e., hourly) and summing these to get the mean daily rate. Many environmental factors other than temperature also affect leaf appearance rate. However, once the proper temperature response function for leaf appearance rate is determined, it is much easier to determine when and how other factors are involved to modify the leaf appearance rate under a given environment.Key words: Temperature, leaf appearance rate, phyllochron, wheat, corn, beta function </jats:p
Predicting the time to 50% seedling emergence in wheat using a Beta model
No full textAbstractThe timing of seedling emergence greatly affects growth and yield of wheat (Triticum aestivum L.) and a good growth model should predict it accurately. The Cropping System Model of the Decision Support System for Agrotechnology Transfer (DSSAT-CSM) is used worldwide for many different applications, but its simulation of the timing of seedling emergence of wheat is not satisfactory under certain circumstances. In order to improve the prediction of seedling emergence, we incorporated a newly developed non-linear model, the Beta model, into DSSAT-CSM. Simulation performances were tested using observations in spring wheat (cv. Thatcher) from 24 sites across North America over the period 1930–1954, which totalled 244 site-years. Observed days from sowing to 50% seedling emergence (DSE) ranged from 5 to 39. The DSSAT-CSM model underestimated DSE in most cases. The Beta model using daily air temperature markedly improved prediction of seedling emergence. When using hourly air temperature, the Beta model generally resulted in predictions similar to when daily air temperature was used. However, calculated hourly temperature improved the simulation when the daily air temperature was near the base temperature for germination/emergence. When temperature was adjusted using a DSSAT-CSM-calculated soil moisture factor for germination/emergence (WFGE), the prediction was not improved, which could be related to the inaccurate simulation of near-surface soil moisture and the calculation of WFGE. The performance of the Beta model using soil temperature at sowing depth was not as good as simulations using air temperature, suggesting that the simulated soil temperature might not have been accurate. To further improve the prediction it is necessary to improve the simulation of near-surface soil moisture and temperature and the calculation of WFGE. Further work could also be done to simulate the dynamics of seedling emergence
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