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51.
We have fabricated active-matrix organic light emitting diode (AMOLED) test arrays on an optically clear high-temperature flexible plastic substrate at process temperatures as high as 285 degC using amorphous silicon thin-film transistors (a-Si TFTs). The substrate transparency allows for the operation of AMOLED pixels as bottom-emission devices, and the improved stability of the a-Si TFTs processed at higher temperatures significantly improves the reliability of the light emission over time.  相似文献   
52.
With the recent ban of pentabromodiphenyl ether (technical PentaBDE) and octabromodiphenyl ether (technical OctaBDE) mixtures in the European Union (EU) and in parts of the United States, decabromodiphenyl ether (technical DecaBDE) remains as the only polybrominated diphenyl ether (PBDE) based flame retardant available, today. The EU risk assessment report for DecaBDE identified a high level of uncertainty associated with the suitability of the current risk assessment approach for secondary poisoning by debromination of DecaBDE to toxic lower brominated diphenylethers. Addressing this still open question, we investigated concentrations and temporal trends of DecaBDE, NonaBDE, and OctaBDE congeners in the sediments of Greifensee, a small lake located in an urban area close to Zürich, Switzerland. PBDE appeared first in sediment layers corresponding to the mid 1970s. While total Tri-HeptaBDE (BDE-28, -47, -99, -100, -153, -154 and -183) concentrations leveled off in the mid 1990s to about 1.6 ng/g dw (dry weight), DecaBDE levels increased steadily to 7.4 ng/g dw in 2001 with a doubling time of 9 years. Hexabromocyclododecanes (HBCD) appeared in Greifensee sediments in the mid 1980s. They are an important class of flame retardants that are being used in increasing amounts, today. As was observed for DecaBDE, HBCD concentrations were continuously increasing to reach 2.5 ng/g dw in 2001. Next to DecaBDE, all 3 NonaBDE congeners (BDE-208, BDE-207, and BDE-206) and at least 7 out of the 12 possible OctaBDE congeners (BDE-202, BDE-201, BDE-197/204, BDE-198/203, BDE-196/200, BDE-205, and BDE-194) were detected in the sediments of Greifensee. Highest concentrations were found in the surface sediments with 7.2, 0.26, 0.14, and 1.6 ng/g dw for Deca-, Nona-, Octa-, and the sum of Tri-HeptaBDE, respectively. While DecaBDE and NonaBDE were found to increase rapidly, the increase of OctaBDE was slower. Congener patterns of Octa- and NonaBDE present in sediments of Greifensee did not change with time. Consequently, there was no evidence for sediment mediated long-term transformation of PBDE within the observed time span of almost 30 years. Despite the high persistence of DecaBDE, environmental debromination occurs, as shown by the detection of a shift in congener patterns of Octa- and NonaBDE in sediments, compared to the respective congener patterns in technical PBDE products. The OctaBDE congener BDE-202 was detected in sediments, representing a transformation product that is not reported in any of the technical PBDE products. Comparison of OctaBDE congener patterns in sediments with OctaBDE congener patterns from known sources reveals that (i) they were distinctively different from the congener patterns in technical PBDE products and (ii) that they were similar to the OctaBDE patterns in house dust and photodegradation products of DecaBDE, suggesting contributions from these sources.  相似文献   
53.
Im Folgenden wird über die Chronologie der Ereignisse im Rahmen des EHEC O104:H4 Ausbruchsgeschehen aus Sicht der Lebensmittelüberwachung in Schleswig-Holstein bis zur Gründung der nationalen Task Force EHEC berichtet. Am Beispiel des Kreises Schleswig-Flensburg wird die Zusammenarbeit und der Informationsaustausch zwischen Gesundheitsbeh?rde und Lebensmittelüberwachung dargestellt. Die erste Information über einen Anstieg an Erkrankungen mit blutigem Durchfall und HUS-Symptomatik in den Kreisen anliegend an und aus Hamburg erhielt das Ministerium für Landwirtschaft, Umwelt und l?ndliche R?ume des Landes Schleswig-Holstein am 19. Mai 2011. Der Fachdienst Veterin?rmedizin und Verbraucherschutz des Kreises Schleswig-Flensburg wurde ebenfalls am 19. Mai 2011 über eine solche H?ufung im Kreis Schleswig-Flensburg in Kenntnis gesetzt. Daraufhin wurden auf Landes- und Kreisebene Ma?nahmen eingeleitet, um zusammen mit den Gesundheitsbeh?rden diesen lebensmittelassoziierten Ausbruch aufzukl?ren. Am 01. Juni 2011 fand erstmalig in Schleswig-Holstein eine Telefonkonferenz zwischen den betroffenen Ministerien und allen Lebensmittelüberwachungs- und Gesundheitsbeh?rden der Kreise und kreisfreien St?dte statt, um das weitere Vorgehen gemeinsam zu koordinieren. Am 03. Juni 2011 wurde in Berlin am Bundesamt für Verbraucherschutz und Lebensmittelsicherheit (BVL) die nationale Task Force EHEC gegründet. Zwei Wochen nachdem die Gesundheitsbeh?rden von geh?uften und l?nderübergreifenden Erkrankungsf?llen Kenntnis hatten, geht damit die Koordinierung der Aufkl?rung von den Gesundheitsbeh?rden auf das BVL über. Am 07. Juni 2011 wurde durch das MLUR ein Mitarbeiter des Kreises Schleswig-Flensburg als Vertreter für Schleswig-Holstein in die Task-Force EHEC nach Berlin entsandt. Als Ergebnis ist aus diesem Erkrankungsgeschehen auch die Lehre zu ziehen, dass vermehrt pflanzliche Lebensmittel zu den „gef?hrlichen Lebensmitteln“ geh?ren. Diese müssen in Zukunft viel st?rker in den Fokus genommen werden.  相似文献   
54.
Magnetic Resonance Materials in Physics, Biology and Medicine - In magnetic resonance imaging (MRI), compressed sensing (CS) enables the reconstruction of undersampled sparse data sets. Thus,...  相似文献   
55.
This paper proposes a basic structured light system for pose estimation. It consists of a circular laser pattern and a camera rigidly attached to the laser source. We develop a geometric modeling that allows to efficiently estimate the pose at scale of the system, relative to a reference plane onto which the pattern is projected. Three different robust estimation strategies, including two minimal solutions, are also presented with this geometric formulation. Synthetic and real experiments are performed for a complete evaluation, both quantitatively and qualitatively, according to different scenarios and environments. We also show that the system can be embedded for UAV experiments.  相似文献   
56.
The quality of dried meat products and their drying kinetics significantly depends on the status of the raw material going into the drying process. The aim of this study was to determine the impact of meat status (fresh, mature, frozen–thawed) on the drying kinetics and the resulting quality in terms of color changes and spectrally deductible information. Drying tests were conducted using meat from organically raised bulls. In the fresh meat, freezing leads to a decrease in the drying rate, while for matured meat, the opposite is true. Aging and freezing have little effect on the end product quality in terms of final product color. However, water content can be detected hyperspectrally and resolved spatially for all stages of the process. With regard to water content prediction, the Monte-Carlo uninformative variable elimination-partial least square method performs best for the fresh and fresh frozen–thawed version with seven wavelengths, an r2 of 0.97 and 0.88, and RMSE (Root mean squared error) of 0.15 and 0.17 for the test set, respectively.  相似文献   
57.
Objective: To determine the most effective ways to present human papillomavirus (HPV) vaccine risk and benefit information to mothers in Hispanic, African American, and White communities, to increase mothers’ intentions to vaccinate their daughters against HPV. Design: The study used a 3 × 2 between-subjects factorial design, involving 3 different risk presentation formats (graphical HPV statistics, nongraphical HPV statistics, or no-statistics control) and the presence or absence of rhetorical questions (RQ). Data were collected from a national sample of 471 mothers of girls ages 11–16. Main Outcome Variables: The primary outcome variable was mothers’ intention to vaccinate their daughters against HPV. Secondary outcomes included mothers’ self-reported message comprehension and perceptions of daughters’ vulnerability to HPV infection, infection severity, vaccine efficacy, and obstacles to immunization. Results and Conclusion: Results showed that both risk presentation format and RQs had an overall positive effect on mothers’ intention to vaccinate their daughters. However, the interventions appear to be more effective when used separately than when used in combination. Each of these interventions is brief and could easily be implemented by health care providers as well as in patient health communication literature. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
As a profession we are committed to maintaining and enhancing our competence as psychologists in order to most effectively serve the public throughout our careers. While this is a widely shared commitment among psychologists, there is considerably less consensus regarding how best to accomplish this goal. This dilemma is examined from the ethical, educational and legal perspectives. The American Psychological Association (APA) Ethics Code clearly articulates that competence is an ethical duty, although there is little guidance provided in the code as to how to meet this standard. As a profession we have tended to focus on the construct of life-long learning and we have incorporated this principle into our education and training standards. In fact, APA accreditation requires that doctoral programs inculcate this value into our foundational training. The majority of Psychology Licensing Boards have addressed this issue through the endorsement of mandatory continuing education requirements that primarily focus on hours and the content or structure of approved programs. Potential limitations to our ability to effectively self-assess our professional training needs are discussed and several innovative models are presented for integrating effective self-assessment and continuing education. Three invited experts provide commentaries that further explore the challenges and dilemmas posed by the ethical, legal and professional duty to maintain and enhance competence throughout our professional careers. These commentaries broaden the considerations, provide practical suggestions from other professions and provide a vision for the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
59.
Safe, reliable, and efficient tritium management in the breeder blanket will have to face unprecedented technological challenges. Beside the efficiency for tritium recovery from the breeder blanket (Tritium Extraction (TES) and Coolant Purification Systems (CPS)), the accuracy for tritium tracking between the inner and the outer fuel cycle must also be demonstrated. This paper focuses on the recent R&D carried out at the Tritium Laboratory Karlsruhe to tackle these issues. For ITER, the recently consolidated TES and CPS designs comprise adsorption columns and getter beds operated in semi-continuous mode. Different approaches for the tritium accountancy stage (TAS) have been evaluated. Balancing static (batch-wise gas collection at the TBM outlets and the tritium plant) or dynamic (in/on-line) approaches with respect to the expected analytical performances and integration issues, the first conceptual design of the TAS for EU TBMs is presented. For DEMO, the overall strategy for tritium recovery and tracking has been revisited. The necessity for on-line real-time tritium accountancy and improved process efficiency suggest the use of continuous processes such as permeator and catalytic membrane reactor. The main benefits combining the PERMCAT process with advanced membranes is discussed with respect to process improvements and facilitated accountancy using spectroscopic methods.  相似文献   
60.
The objectives of this study were (1) to develop an algorithm for the acceleration sensor of the Smartbow Eartag (Smartbow GmbH, Weibern, Austria) to distinguish between postures (lying and standing or locomotion) and to detect 6 kinds of activities (milk intake, water intake, solid feed intake, ruminating, licking or sucking without milk intake, and other activities) in dairy calves and (2) to evaluate this sensor for identifying these behaviors in dairy calves compared with observations from video. Accelerometers were applied to the left ears of 15 preweaned Holstein dairy calves. Calves were kept in a group pen and received milk replacer from an automatic calf feeder. Based on 38 h of acceleration data and video observation, an algorithm was established to detect the predefined behaviors. Using cross-validation, video recordings were used to analyze whether a behavior was detected correctly by the developed algorithm. For posture, sensitivity (94.4%), specificity (94.3%), precision (95.8%), and accuracy (94.3%) were high. Cohen's kappa was calculated as 0.88. For the 6 defined activities, overall (i.e., aggregated for all activities) accuracy was 70.8% and kappa was calculated as 0.58. Some activities (e.g., ruminating, feed intake, other activities) were identified better than others. In conclusion, the developed algorithm based on the acceleration data of the Smartbow Eartag was successful in detecting lying behavior, rumination, feed intake, and other activities in calves, but further development of the underlying algorithm will be necessary to produce reliable results for milk and water intake.  相似文献   
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