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81.
In the world of OTIS, an online Internet School for occupational therapists, students from four European countries were encouraged to work collaboratively through problem-based learning by interacting with each other in a virtual semi-immersive environment. This paper describes, often in their own words, the experience of European occupational therapy students working together across national and cultural boundaries. Collaboration and teamwork were facilitated exclusively through an online environment, since the students never met each other physically during the OTIS pilot course. The aim of the paper is to explore the observations that (1) there was little interaction between students from different tutorial groups and (2) virtual teamwork developed in each of the cross-cultural tutorial groups. Synchronous data from the students was captured during tutorial sessions and peer-booked meetings and analyzed using the qualitative constructs of immersion, presence and reflection in learning. The findings indicate that immersion was experienced only to a certain extent. However, students found both presence and shared presence, within their tutorial groups, to help collaboration and teamwork. Other evidence suggests that communities of interest were established. Further study is proposed to support group work in an online learning environment. It is possible to conclude that collaborative systems can be designed, which encourage students to build trust and teamwork in a cross cultural online learning environment.This revised version was published online in March 2005 with corrections to the cover dateFunded by the European Union through the TENTelecom programme. 相似文献
82.
Mary Frances Sorrels Raymond Reiser 《Journal of the American Oil Chemists' Society》1957,34(3):131-134
Summary and Conclusion A scheme for the separation and identification of some constituents of marine oils was developed. A preliminary separation
on a silicic acid column with five solvent systems was followed by further separation and identification on silicic acid impregnated
glass-fiber filter paper. This method can be used successfully for qualitative determinations, but the irregularities in the
density of the glass paper prevent an accurate quantitative assay.
Supported, in part, by grants from the Fish and Wildlife Service of the United States Department of the Interior, the Robert
A. Welch Foundation, and the Office of Naval Research. 相似文献
83.
Phase diagrams for the Co-Cr-Ta and Co-Cr-Nb systems have been calculated from thermodynamic data for the binary systems involved. Eleven isothermal sections for temperatures between 2200 and 1500 K are given. The calculations are in good agreement with the limited available experimental phase diagram data for these systems. 相似文献
84.
85.
Isaac Deng Frances Corrigan Sanjay Garg Xin-Fu Zhou Larisa Bobrovskaya 《International journal of molecular sciences》2021,22(14)
Parkinson’s disease (PD) is the most common movement disorder, characterized by progressive degeneration of the nigrostriatal pathway, which consists of dopaminergic cell bodies in substantia nigra and their neuronal projections to the striatum. Moreover, PD is associated with an array of non-motor symptoms such as olfactory dysfunction, gastrointestinal dysfunction, impaired regulation of the sleep-wake cycle, anxiety, depression, and cognitive impairment. Inflammation and concomitant oxidative stress are crucial in the pathogenesis of PD. Thus, this study aimed to model PD via intrastriatal injection of the inflammagen lipopolysaccharide (LPS)to investigate if the lesion causes olfactory and motor impairments, inflammation, oxidative stress, and alteration in synaptic proteins in the olfactory bulb, striatum, and colon. Ten µg of LPS was injected unilaterally into the striatum of 27 male C57BL/6 mice, and behavioural assessment was conducted at 4 and 8 weeks post-treatment, followed by tissue collection. Intrastriatal LPS induced motor impairment in C57BL/6 mice at 8 weeks post-treatment evidenced by reduced latency time in the rotarod test. LPS also induced inflammation in the striatum characterized by increased expression of microglial marker Iba-1 and astrocytic marker GFAP, with degeneration of dopaminergic neuronal fibres (reduced tyrosine hydroxylase immunoreactivity), and reduction of synaptic proteins and DJ-1 protein. Additionally, intrastriatal LPS induced inflammation, oxidative stress and alterations in synaptic proteins within the olfactory bulb, although this did not induce a significant impairment in olfactory function. Intrastriatal LPS induced mild inflammatory changes in the distal colon, accompanied by increased protein expression of 3-nitrotyrosine-modified proteins. This model recapitulated the major features of PD such as motor impairment and degeneration of dopaminergic neuronal fibres in the striatum, as well as some pathological changes in the olfactory bulb and colon; thus, this model could be suitable for understanding clinical PD and testing neuroprotective strategies. 相似文献
86.
An analysis technique to assess the viability of digital image correlation (DIC) in tracking the full‐field strains across the surface of hanging historic tapestries is presented. Measurement uncertainty related to the use of the inherent tapestry image in tracking displacements is investigated through use of “synthetic” deformation fields. The latter are generated by mapping the details of a given tapestry image into finite element analyses. The combination of self‐weight loading, material non‐linearity, and image specific heterogeneity (related to slit stitching, damage, and patch‐restorations) serve to generate a bespoke deformation field complex enough to assess the reliability of DIC measurements. Accuracy is evaluated by comparing measured results with the original known deformations. The technique demonstrates that the optimum imaging settings and the choice of subset size for DIC analysis are strongly influenced by the tapestry image and the goal of the measurement, they are found using a compromise between conflicting objectives: minimising measurement error while maximising resolution. 相似文献
87.
Qian Chen Quanyin Hu Elena Dukhovlinova Guojun Chen Sarah Ahn Chao Wang Edikan A. Ogunnaike Frances S. Ligler Gianpietro Dotti Zhen Gu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(23)
Chimeric antigen receptor (CAR)‐redirected T lymphocytes (CAR T cells) show modest therapeutic efficacy in solid tumors. The desmoplastic structure of the tumor and the immunosuppressive tumor microenvironment usually account for the reduced efficacy of CAR T cells in solid tumors. Mild hyperthermia of the tumor reduces its compact structure and interstitial fluid pressure, increases blood perfusion, releases antigens, and promotes the recruitment of endogenous immune cells. Therefore, the combination of mild hyperthermia with the adoptive transfer of CAR T cells can potentially increase the therapeutic index of these cells in solid tumors. It is found that the chondroitin sulfate proteoglycan‐4 (CSPG4)‐specific CAR T cells infused in Nod scid gamma mice engrafted with the human melanoma WM115 cell line have superior antitumor activity after photothermal ablation of the tumor. The findings suggest that photothermal therapy facilitates the accumulation and effector function of CAR T cells within solid tumors. 相似文献
88.
The decomposition of FeS2, both as a single phase and as it exists in coal, has been studied between 250 and 350 °C, in hydrogen and nitrogen atmospheres, and in the presence of a coal-derived solvent. The first-order rate constant for decomposition of FeS2 at 350 °C with H2 alone is 6.7 × 10?1min?1; with H2 and coal-derived solvent, it is 5.5 × 10?2min?1; for FeS2 contained within coal, solvent and H2, it is 8.6 × 10?3min?1. Although the rate constant for decomposition is dependent upon temperature and the system, the activation energy in each case has been calculated to be 88 kJ mol?1. A mechanism consistent with these data is the thermal decomposition of FeS2 to produce Fe1?xS and S, followed by reaction of the sulphur with available hydrogen (from H2, solvent or coal) to form H2S. 相似文献
89.
Sridharshi Chintha Hewawitharana Frances Elizabeth Thompson Catherine M. Loria Warren Strauss Jyothi Nagaraja Lorrene Ritchie Karen Lucy Webb 《Nutrition journal》2018,17(1):111
Background
A dietary screener questionnaire (DSQ) was used to assess dietary outcomes among children in the Healthy Communities Study (HCS), a study of the relationships between programs and policies to prevent child obesity and child diet, physical activity and weight outcomes.Methods
To compare dietary intake estimates derived from the DSQ against those from the Automated Self-Administered 24-Hour Recalls for Children (ASA24-Kids) among children, a measurement error model, using structural equation modelling, was utilized to estimate slopes, deattenuated correlation coefficients, and attenuation factors by age and sex, ethnicity, and BMI status.Participants/setting
A randomly selected sub-sample of HCS participants aged 4–15 years in 130 communities throughout the U.S. who completed the DSQ and up to two ASA24-Kids recalls (n?=?656;13% of HCS participants).Results
For most nutrient/foods examined, the DSQ yielded larger mean intake estimates than the ASA24-Kids, and agreement between the two measures varied by food/nutrient, age and sex, ethnicity, and BMI category. Deattenuated correlation coefficients of 0.4 or greater were observed for added sugars from SSBs (0.54), fruits and vegetables (0.40), and dairy foods (0.50). Lower deattenuated correlation coefficients were seen for total added sugars (0.37), whole grains (0.34), and fiber (0.34). Attenuation factors were most severe for total added sugars intake among overweight children, and for several other dietary outcomes among children aged 9–11 years.Conclusions
The DSQ was found to be a tool with acceptable agreement with the ASA24-Kids for measuring multiple dietary outcomes of interest in the HCS, although there may be potential due to measurement error to underestimate results (bias towards the null). In future studies, measurement error modelling and regression calibration may be possible solutions to correct for bias due to measurement error in most food/nutrient intake estimates from the DSQ when used among children.90.