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1.
Kathryn M. Denkowski George C. Denkowski 《Applied psychophysiology and biofeedback》1984,9(3):353-364
This study examined whether group progressive relaxation training was as effective as individual EMG biofeedback training in facilitating the academic achievement and self-control of 45 hyperactive elementary school children. Academic achievement was assessed with the Gates-MacGinities Reading Tests, and self-control was measured with the Nowicki-Strickland and the Teacher Rating scales. Eight sessions were scheduled at weekly intervals. Progressive relaxation was conducted in groups of seven or eight and was induced with a commercial audiocassette program. EMG training augmented frontalis biofeedback with those taped exercises. A placebo group listened to taped children's stories. Multivariate analysis of variance indicated no significant differences among the three contrast groups when all dependent variables were considered together. However, univariate F values and discriminant analysis disclosed locus of control to be significantly more internal for the progressive relaxation condition. Also, differences between the two relaxation and the placebo groups, though not statistically significant, were all in the expected direction. While the relative efficacy of group progressive relaxation could not be established conclusively, the data appeared sufficiently positive to warrant further investigation of this cost-effective prospective intervention.The opinions expressed by the authors are not necessarily those of their respective institutions. 相似文献
2.
The present study was carried out on the non-tidal reaches of the River Ely, South Wales, from October 1979 to October 1980. The seasonal variations of the chlorophyll-a content of the phytoplankton was unimodal with one maximum in May and a minimum in December. The chlorophyll-a content varied from 0.277 to 41.259 mg m?3. The primary productivity showed a bimodal seasonal distribution with two maxima in May and September and lower values throughout the remainder of the year, particularly in winter. The value for the primary productivity varied from 0.269 to 24.302 mg C m?3 h?1. A positive correlation was obtained between chlorophyll-a content and primary productivity. The seasonal distribution of the dominant algal species and the saprobity of the River Ely were also studied. The diatom species almost showed a similar seasonal periodicity. Their concentrations were low during the winter months and high during most of the spring and summer months. Many of the dominant diatom species found in the phytoplankton populations were either considered by the other authors as saprobic (Nitzchia palea) or as inhabitants of eutrophic waters (Gomphonema parvulum, Navicula cryptocephala and Synedra ulna). Chlamydomonas spp. were the most abundant green algae followed by Chlorella vulgaris. The effect of sewage effluent disposal and cattle excreta at three of the sampling sites might partly explain the presence of high Chlamydomonas spp. populations at those sites. Physical factors (low flow rates, high transparency and water temperature) and organic pollution at some sampling sites seemed to play an important role in increasing the number of algal species during spring and summer. The non-tidal reaches of the River Ely were found to be β-mesosaprobic above and below Station 5 and α-mesosaprobic at the latter station and therefore, the river can be considered as polluted at Station 5 and mildly polluted at the others. 相似文献
3.
Kathryn E. Stecke 《Flexible Services and Manufacturing Journal》1989,1(4):287-324
This article is a detailed case study of a particular FMS that will be operational in 1989. It describes the daily planning and operating problems that will need to be addressed. The algorithms that will operate this system are presented. Given the daily changing production requirements, the algorithms begin with an aggregate planning feasibility check. Then planning, scheduling, inventory management, and breakdowns are addressed. The key problems in operating this system are tool management problems. Detailed tooling data and their analysis are presented in an appendix to address these problems. 相似文献
4.
Intraprotoplasmic feruloylation of arabinoxylans in Festuca arundinacea cell cultures 总被引:2,自引:2,他引:0
Graminaceous primary cell walls contain polysaccharides to which are esterified feruloyl residues. Ester biosynthesis is highly specific and the present experiments were performed to ascertain the likely site of feruloylation in living grass cell cultures. Cell cultures of tall fescue grass (Festuca arundinacea Schreber) incorporated exogenous l-[1-3H]arabinose into polymers at a linear rate after a short lag of approx. 1–3 min. Radiolabelled polymers did not start to accumulate in the culture medium until 20–35 min after [3H]arabinose was supplied. However, polymer-bound feruloyl-arabinose residues began to accumulate 3H after a lag of 1–3 min. Assuming that the onset of secretion of radiolabelled polymers into the medium indicates the time before which essentially all the radiolabel was internal to the plasma membrane, the results show that the polysaccharide-bound [3H]arabinose residues must have been feruloylated within the protoplast.Abbreviations AIR
alcohol-insoluble residue
- BAW
butan1-ol/acetic acid/water (12:3:5 by volume)
- BEW
butan-1-ol/ ethanol/water (20:5:11 by volume)
- EPW
ethyl acetate/pyridine/ water (8:2:1 by volume)
- RAra
Chromatographic mobility relative to that of l-arabinose
We are very grateful to Mr. Gundolf Wende for assistance with the characterisation of the feruloyl esters. K.E.M. is funded by a studentship from the Science and Engineering Research Council in collaboration with Zeneca Agrochemicals. 相似文献
5.
Paula Sobenko Hatum Kathryn McMahon Kerrie Mengersen Paul PaoYen Wu 《Ecology and evolution》2022,12(8)
In general, it is not feasible to collect enough empirical data to capture the entire range of processes that define a complex system, either intrinsically or when viewing the system from a different geographical or temporal perspective. In this context, an alternative approach is to consider model transferability, which is the act of translating a model built for one environment to another less well‐known situation. Model transferability and adaptability may be extremely beneficial—approaches that aid in the reuse and adaption of models, particularly for sites with limited data, would benefit from widespread model uptake. Besides the reduced effort required to develop a model, data collection can be simplified when transferring a model to a different application context. The research presented in this paper focused on a case study to identify and implement guidelines for model adaptation. Our study adapted a general Dynamic Bayesian Networks (DBN) of a seagrass ecosystem to a new location where nodes were similar, but the conditional probability tables varied. We focused on two species of seagrass (Zostera noltei and Zostera marina) located in Arcachon Bay, France. Expert knowledge was used to complement peer‐reviewed literature to identify which components needed adjustment including parameterization and quantification of the model and desired outcomes. We adopted both linguistic labels and scenario‐based elicitation to elicit from experts the conditional probabilities used to quantify the DBN. Following the proposed guidelines, the model structure of the general DBN was retained, but the conditional probability tables were adapted for nodes that characterized the growth dynamics in Zostera spp. population located in Arcachon Bay, as well as the seasonal variation on their reproduction. Particular attention was paid to the light variable as it is a crucial driver of growth and physiology for seagrasses. Our guidelines provide a way to adapt a general DBN to specific ecosystems to maximize model reuse and minimize re‐development effort. Especially important from a transferability perspective are guidelines for ecosystems with limited data, and how simulation and prior predictive approaches can be used in these contexts. 相似文献
6.
Kathryn Campbell Robert J. Gifford Joshua Singer Verity Hill Aine OToole Andrew Rambaut Katie Hampson Kirstyn Brunker 《PLoS pathogens》2022,18(5)
The availability of pathogen sequence data and use of genomic surveillance is rapidly increasing. Genomic tools and classification systems need updating to reflect this. Here, rabies virus is used as an example to showcase the potential value of updated genomic tools to enhance surveillance to better understand epidemiological dynamics and improve disease control. Previous studies have described the evolutionary history of rabies virus, however the resulting taxonomy lacks the definition necessary to identify incursions, lineage turnover and transmission routes at high resolution. Here we propose a lineage classification system based on the dynamic nomenclature used for SARS-CoV-2, defining a lineage by phylogenetic methods for tracking virus spread and comparing sequences across geographic areas. We demonstrate this system through application to the globally distributed Cosmopolitan clade of rabies virus, defining 96 total lineages within the clade, beyond the 22 previously reported. We further show how integration of this tool with a new rabies virus sequence data resource (RABV-GLUE) enables rapid application, for example, highlighting lineage dynamics relevant to control and elimination programmes, such as identifying importations and their sources, as well as areas of persistence and routes of virus movement, including transboundary incursions. This system and the tools developed should be useful for coordinating and targeting control programmes and monitoring progress as countries work towards eliminating dog-mediated rabies, as well as having potential for broader application to the surveillance of other viruses. 相似文献
7.
Maternal transfer of strain-specific immunity in an invertebrate 总被引:10,自引:0,他引:10
The most celebrated component of the vertebrate immune system is the acquired response in which memory cells established during primary infection enhance the proliferation of antibodies during secondary infection. Additionally, the strength of vertebrate acquired immune responses varies dramatically depending on the infecting pathogen species or on the pathogen genotype within species. Because invertebrates lack the T-cell receptors and Major Histocompatibility Complex (MHC) molecules that mediate vertebrate adaptive immune responses, they are thought to lack adaptive immunity and be relatively unspecific in their interactions with pathogens. With only innate immunity, invertebrate hosts are believed to be nai;ve at each new encounter with pathogens. Nevertheless, some forms of facultative immunity appear to be important in insects; some individuals have enhanced immunity due to population density, and some social insects benefit when their nest-mates have been exposed to a pathogen or pathogen mimic (; see for a predation example.) Here we provide evidence for acquired strain-specific immunity in the crustacean Daphnia magna infected with the pathogenic bacteria Pasteuria ramosa. Specifically, the fitness of hosts was enhanced when challenged with a bacterial strain their mother had experienced relative to cases when mother and offspring were challenged with different strains. 相似文献
8.
Differential effect of three-repeat and four-repeat tau on mitochondrial axonal transport 总被引:1,自引:0,他引:1
Will Stoothoff† Phillip B. Jones Tara L. Spires-Jones Daniel Joyner Ekta Chhabra Kathryn Bercury‡ Zhanyun Fan Hong Xie Brian Bacskai Jon Edd§ Daniel Irimia§ Bradley T. Hyman 《Journal of neurochemistry》2009,111(2):417-427
Tau protein is present in six different splice forms in the human brain and interacts with microtubules via either 3 or 4 microtubule binding repeats. An increased ratio of 3 repeat to 4 repeat isoforms is associated with neurodegeneration in inherited forms of frontotemporal dementia. Tau over-expression diminishes axonal transport in several systems, but differential effects of 3 repeat and 4 repeat isoforms have not been studied. We examined the effects of tau on mitochondrial transport and found that both 3 repeat and 4 repeat tau change normal mitochondrial distribution within the cell body and reduce mitochondrial localization to axons; 4 repeat tau has a greater effect than 3 repeat tau. Further, we observed that the 3 repeat and 4 repeat tau cause different alterations in retrograde and anterograde transport dynamics with 3 repeat tau having a slightly stronger effect on axon transport dynamics. Our results indicate that tau-induced changes in axonal transport may be an underlying theme in neurodegenerative diseases associated with isoform specific changes in tau's interaction with microtubules. 相似文献
9.
10.
William J. Sutherland Rosalind Aveling Thomas M. Brooks Mick Clout Lynn V. Dicks Liz Fellman Erica Fleishman David W. Gibbons Brandon Keim Fiona Lickorish Kathryn A. Monk Diana Mortimer Lloyd S. Peck Jules Pretty Johan Rockström Jon Paul Rodríguez Rebecca K. Smith Mark D. Spalding Femke H. Tonneijck Andrew R. Watkinson 《Trends in ecology & evolution》2014