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51.
52.
F Leutmezer W Serles J Lehrner E Pataraia K Zeiler C Baumgartner 《Canadian Metallurgical Quarterly》1998,51(4):1175-1177
We report postictal nose wiping as a postictal symptom of localizing and lateralizing significance in focal epilepsy. We reviewed videotapes of 444 focal seizures in 101 patients who underwent prolonged video and EEG monitoring during presurgical epilepsy evaluation, and observed postictal nose wiping in 51.3% of 76 patients with temporal lobe epilepsy. The hand used to perform postictal nose wiping was ipsilateral to the side of seizure origin in 86.5% of all seizures and in 97.3% of all patients. We conclude that postictal nose wiping is a common, easily assessed symptom after focal seizures of temporal lobe origin that provides reliable lateralizing information on the side of seizure onset. 相似文献
53.
Gustav Lymer Jonas Ivarsson Oskar Lindwall 《International Journal of Computer-Supported Collaborative Learning》2009,4(4):423-444
This study investigates video recordings of design reviews in architectural education, focusing on how presentations and discussions
of designs are contingent on the specific tools employed. In the analyzed recordings, three different setups are utilized:
traditional posters, digital slide-show technologies, and combinations of the two. This range of different setups provides
a set of contrasts that make visible the role of technologies in shaping the ways in which the reviews are conducted. The
analysis is structured in three themes. First, we examine the sequential organization of digital presentations in relation
to the spatial structure of poster-based presentations. Second, the different ways in which shared attention is established
in digital, paper-based, and hybrid presentation practices are analyzed. Third, we address part-whole relations—how details
in presented materials are put in relation to the overarching project or the presentation as a whole. Taken together, the
analyses suggest that the detailed organization of the design review is transformed in subtle yet consequential ways through
the introduction of digital slide-show technologies. These transformations are consequential not only locally, for the design
review itself, but also for the instructive work that is accomplished through this practice. We conclude by discussing some
implications for design, arguing that an increased awareness of how the practice is influenced by the different setups might
be key for the proper adaptation of presentation technologies to particular purposes. 相似文献
54.
J Lehrner C Baumgartner W Serles A Olbrich E Pataraia J Bacher S Aull L Deecke 《Canadian Metallurgical Quarterly》1997,38(9):1042-1044
PURPOSE: We report a patient with mesial temporal lobe epilepsy (MTLE) with olfactory prodromal symptoms manifested as an unpleasant smell of onions, who was found to have an ipsilateral deficit of olfactory naming (olfactory agnosia). METHODS AND RESULTS: Preoperative olfactory testing revealed a selective right-sided olfactory deficit for naming of odors. Olfactory threshold was within the normal range. The patient has been seizure free after selective amygdalohippocampectomy for 4 months. No olfactory prodromal events have occurred since surgery. Olfactory testing 3 months after resection showed that right-sided odor naming was still impaired. CONCLUSIONS: We conclude that olfactory prodromal symptoms may be associated with unilateral olfactory dysfunction, and lateralization of seizure origin may be possible by unilateral olfactory testing. 相似文献
55.
Summary Living cationic polymerization of isobutul vinyl ether (IBVE), initiated by1-iodo-1-(2-methyl propyloxy)-ethane (1) and tetraalkylammonium perchlorate yields polymers of well defined molar masses and end groups. The controlled introduction of end groups was confirmed by a model reaction and was then applied to introduce and azo initiator function. The resulting polymeric initiator was used for the synthesis of a blockcopolymer. 相似文献
56.
Oskar Rexfelt Lars Almefelt Daniel Zackrisson Teres Hallman Johan Malmqvist MariAnne Karlsson 《Research in Engineering Design》2011,22(3):153-171
This paper outlines the results of a project aiming to develop and apply methods for service co-creation with customers, focusing
on the early phases of service development. The project is collaboration between a manufacturing firm in the automotive industry,
one of their B2B-customers (a transportation firm), as well as a university, all in Sweden. The research team selected and
developed methods and work practices for problem analysis, idea generation, development and evaluation of services. Thus doing,
methodological influence was taken from the area of engineering design. The proposed approaches were applied in a service
development experiment mainly based on workshops. The experiment was followed up by an analysis of the resulting output, an
interview series, and an evaluation by peers in focus groups. The goal of this article is to answer the following research
questions: (1) What is the industrial applicability of co-creating services using a structured approach, e.g. what are the
benefits and challenges? (2) What do the different actors contribute with using this approach, and what possible factors influence
the nature and quality of the actors’ contributions? (3) Based on the answers to the questions above, what aspects should
be considered to support situated planning and execution of future service co-creation projects? A central conclusion is that
a structured approach is industrially applicable, but it is also evident that there is no completely universal recipe for
service innovation. Addressing these insights, the paper also contributes with guidelines to support the situation-adapted
set-up of future service co-creation projects. 相似文献
57.
From April 2009 to April 2010, 1,132 samples of different types of chicken meat were tested qualitatively and quantitatively for thermotolerant campylobacters. Samples were recovered at retail in shops from the entire territory of Switzerland and comprised imported meat and meat from domestic production. The meat categories covered by the study were refrigerated and frozen meat, meat with and without skin, and meat preparations. Overall, 38.4% of the samples were positive, and in 27.8%, Campylobacter bacteria could be quantified. Counts ranged from ≥10 to <10(4) CFU/g with a maximum value of 8 × 10(3) CFU/g in a sample of refrigerated chicken meat with skin. The contamination frequencies were 45.2% in meat with skin, 40.8% in meat without skin, and 27.4% in meat preparations. Refrigerated meat was contaminated with Campylobacter bacteria more often than frozen meat (53.9 versus 20.0%). The study also showed considerable differences between the contamination rates found for samples from different large retail chains. In 2010, a further study with 120 samples of refrigerated and sliced chicken meat and fresh chicken liver was carried out in order to test a possible seasonal variation of the occurrence of Campylobacter bacteria. The contamination frequency of sliced meat increased from 10.0% in the period from February to March to 36.7% during July to August. In both sampling periods, the counts remained in the range of ≥10 to <100 CFU/g with a maximum value of 30 CFU/g. For chicken liver, a 10.0% contamination rate was observed in the period from December to January, which rose to 100% in the period from August to October. Contrary to the results for sliced meat, not only did the frequency of contamination increase but so did the Campylobacter counts, with the highest recorded value being 2.2 × 10(4) CFU/g. 相似文献
58.
In wastewater treatment plants, the reject water from the sludge treatment processes typically contains high ammonium concentrations, which constitute a significant internal nitrogen load in the plant. Often, a separate nitrification reactor is used to treat the reject water before it is fed back into the plant. The nitrification reaction consumes alkalinity, which has to be replenished by dosing e.g. NaOH or Ca(OH)2. In this study, we investigated the use of a two-compartment microbial fuel cell (MFC) to redistribute alkalinity from influent wastewater to support nitrification of reject water. In an MFC, alkalinity is consumed in the anode compartment and produced in the cathode compartment. We use this phenomenon and the fact that the influent wastewater flow is many times larger than the reject water flow to transfer alkalinity from the influent wastewater to the reject water. In a laboratory-scale system, ammonium oxidation of synthetic reject water passed through the cathode chamber of an MFC, increased from 73.8 ± 8.9 mgN/L under open-circuit conditions to 160.1 ± 4.8 mgN/L when a current of 1.96 ± 0.37 mA (15.1 mA/L total MFC liquid volume) was flowing through the MFC. These results demonstrated the positive effect of an MFC on ammonium oxidation of alkalinity-limited reject water. 相似文献
59.
Indoor air pollution (IAP) from domestic biomass combustion is an important health risk factor, yet direct measurements of personal IAP exposure are scarce. We measured 24-h integrated gravimetric exposure to particles < 2.5 μm in aerodynamic diameter (particulate matter, PM?.?) in 280 adult women and 240 children in rural Yunnan, China. We also measured indoor PM?.? concentrations in a random sample of 44 kitchens. The geometric mean winter PM?.? exposure among adult women was twice that of summer exposure [117 μg/m3 (95% CI: 107, 128) vs. 55 μg/m3 (95% CI: 49, 62)]. Children's geometric mean exposure in summer was 53 μg/m3 (95% CI: 46, 61). Indoor PM?.? concentrations were moderately correlated with women's personal exposure (r=0.58), but not for children. Ventilation during cooking, cookstove maintenance, and kitchen structure were significant predictors of personal PM?.? exposure among women primarily cooking with biomass. These findings can be used to develop exposure assessment models for future epidemiologic research and inform interventions and policies aimed at reducing IAP exposure. PRACTICAL IMPLICATIONS: Our results suggest that reducing overall PM pollution exposure in this population may be best achieved by reducing winter exposure. Behavioral interventions such as increasing ventilation during cooking or encouraging stove cleaning and maintenance may help achieve these reductions. 相似文献
60.
The affect of carbon black and various colourizing pigments on the ultraviolet (UV) stability of high and low density polyethylene
(HDPE and LDPE) was determined using a novel method for the analysis of oxygen uptake profiles. Samples were exposed to 0.27
Wm−2 (measured at 340 nm) UV irrdiation at 25.0±0.1° C in air at 1.0 atm. The usefulness of this method of assessment of UV stability
is demonstrated. The method also enables the rapid collection of data that enable the comparison of the relative photostabilities
of experimental and commercial formulations containing pigments and stabilizing additives. The results show that carbon black
is an effective UV screening agent for HDPE when added at levels as low as 0.05% (wt/wt) and that increased photoprotection
is achieved with increasing concentration of carbon black, up to 5% (wt/wt), above which there is no further significant increase
in photostability. LDPE containing ultramarine blue pigment (Na7Al6Si6O24S3) exhibits relatively poor photostability, whereas ferric oxide (Fe2O3) and chrome orange (PbCrO4.PbO) pigments are better photostabilizers for this material. Cadmium sulphide (CdS) was found to photosensitize LDPE. A compound
containing 0.10% (wt/wt) carbon black, 0.12% (wt/wt) titanium dioxide (TiO2) and 1.78% (wt/wt) phthalocyanine green (C33H2N8Cl14Cu) is an effective formulation for the stabilization of LDPE. Formulations of LDPE containing ultramarine blue-TiO2 or ferric oxidecarbon black combinations absorb heat on exposure and this may affect their photostability. 相似文献