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991.
A. Hokkanen I. Stuns P. Schmid A. Kokkonen F. Gao A. Steinecker J. Budczies P. Heimala L. Hakalahti 《Biomicrofluidics》2015,9(5)
We have developed a microfluidics based sampling system for tissue analytics. The proof-of-concept of the sampling system was demonstrated by extracting lipid samples from tissue biopsies. The sample collection system consists of a disposable silicon based multiport microneedle integrated with polymer microfluidics. The polymethyl methacrylate polymer microfluidic chip has a 10 μl sample reservoir and actuation membranes for liquid pumping. A special automated robotic system was developed to control the positioning of the needle and the sampling procedure on preselected spots on the tissue. Real breast cancer tissue samples were used to test the feasibility of the sampling system. We successfully measured indicative cancer biomarkers from the tissue surface. Phosphatidylcholine and phosphoethanolamine were extracted from the tissue membrane with methyl tert-butyl ether solvent and detected by mass spectrometry. In the future, this tool could be used in characterization of preoperative biopsies and tumour tissues removed during surgery. 相似文献
992.
Martin K. Klämpfl Philipp B. Philippen Babett H. Lobinger 《Journal of sports sciences》2015,33(7):655-664
The yips is considered a task-specific movement disorder. Its estimated prevalence, however, is high compared to similar neurological movement disorders, possibly resulting from previous studies’ restriction of samples based on skill level, and self-report bias. Alternatively, this high prevalence might be an indication of additional aetiologies, for example the influence of previously played racket sports. We estimated the prevalence of the putting yips across the skill range, using self-reports in one study and a screening test in a second study. We explored if previously played sports matter for the development of the yips. In study 1, yips prevalence (N = 1,306) and golfers’ sports biographies (n = 264) were examined via two online surveys, in which golfers indicated if they were yips-affected. In study 2, golfers (N = 186) putted in a standardised putting test while kinematic and performance measures were recorded. Prevalence was estimated via a kinematic threshold. Sports biographies (n = 119) were obtained via an online survey. Prevalence of currently yips-affected golfers was 22.4% in study 1 and 16.7% in study 2. In both studies, more yips-affected than unaffected golfers had experience in playing racket sports. Yips prevalence remained higher than previously estimated prevalence of other movement disorders but decreased when the whole skill range including professionals and novices was considered. Future studies should use the kinematic screening test instead of self-reports to detect the yips and further investigate the influence of previously played racket sports. 相似文献
993.
A. Zaher S. Li K. T. Wolf F. N. Pirmoradi O. Yassine L. Lin N. M. Khashab J. Kosel 《Biomicrofluidics》2015,9(5)
Implantable drug delivery systems can provide long-term reliability, controllability, and biocompatibility, and have been used in many applications, including cancer pain and non-malignant pain treatment. However, many of the available systems are limited to zero-order, inconsistent, or single burst event drug release. To address these limitations, we demonstrate prototypes of a remotely operated drug delivery device that offers controllability of drug release profiles, using osmotic pumping as a pressure source and magnetically triggered membranes as switchable on-demand valves. The membranes are made of either ethyl cellulose, or the proposed stronger cellulose acetate polymer, mixed with thermosensitive poly(N-isopropylacrylamide) hydrogel and superparamagnetic iron oxide particles. The prototype devices'' drug diffusion rates are on the order of 0.5–2 μg/h for higher release rate designs, and 12–40 ng/h for lower release rates, with maximum release ratios of 4.2 and 3.2, respectively. The devices exhibit increased drug delivery rates with higher osmotic pumping rates or with magnetically increased membrane porosity. Furthermore, by vapor deposition of a cyanoacrylate layer, a drastic reduction of the drug delivery rate from micrograms down to tens of nanograms per hour is achieved. By utilizing magnetic membranes as the valve-control mechanism, triggered remotely by means of induction heating, the demonstrated drug delivery devices benefit from having the power source external to the system, eliminating the need for a battery. These designs multiply the potential approaches towards increasing the on-demand controllability and customizability of drug delivery profiles in the expanding field of implantable drug delivery systems, with the future possibility of remotely controlling the pressure source. 相似文献
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Science education in the United States will increasingly be driven by testing and accountability requirements, such as those mandated by the No Child Left Behind Act, which rely heavily on learning outcomes, or "standards," that are currently developed on a state-by-state basis. Those standards, in turn, drive curriculum and instruction. Given the importance of standards to teaching and learning, we investigated the quality of life sciences/biology standards with respect to genetics for all 50 states and the District of Columbia, using core concepts developed by the American Society of Human Genetics as normative benchmarks. Our results indicate that the states' genetics standards, in general, are poor, with more than 85% of the states receiving overall scores of Inadequate. In particular, the standards in virtually every state have failed to keep pace with changes in the discipline as it has become genomic in scope, omitting concepts related to genetic complexity, the importance of environment to phenotypic variation, differential gene expression, and the differences between inherited and somatic genetic disease. Clearer, more comprehensive genetics standards are likely to benefit genetics instruction and learning, help prepare future genetics researchers, and contribute to the genetic literacy of the U.S. citizenry. 相似文献
996.
Modifications of Recognition Memory Processes in Preterm Children: An Event‐Related Potential Study 下载免费PDF全文
Kerstin H. Kipp Axel Mecklinger Nicole Brunnemann Mohammed G. Shamdeen Juliane Meng‐Hentschel Ludwig Gortner 《Child development》2015,86(2):379-393
Prematurity may cause hippocampal compromise. Therefore, hippocampus‐dependent memory processes (recollection‐based retrieval) may be more impaired than hippocampus‐independent processes (familiarity‐based retrieval). The memory of 18 children born preterm with reduced hippocampal volumes, without neonatal complications (weeks of gestation < 34, weight < 1,600 g), and 15 controls (8–10 years) was tested using an item recognition task. While groups were equal in memory performance, dissociation was found: The event‐related potential (ERP) correlate of familiarity was intact in the preterm group, whereas the correlate of recollection was attenuated. A follow‐up experiment ruled out that this was due to general cognitive deficits. Furthermore, gestational age correlated with the ERP index of recollection. Thus, recognition memory in preterm children may be characterized by a compensation of attenuated recollection by familiarity. 相似文献
997.
Elizabeth H. McEneaney 《课程研究杂志》2015,47(6):802-819
This article offers a critique of Michael Young’s perspective on the Internet as it relates to the knowledge-driven curriculum he supports. I argue that the Internet is a site of both theoretical knowledge and everyday concepts which challenges the differentiation of knowledge that premises much of Young’s writing. Google searches from the perspective of a student and teacher show that theoretical knowledge with vertical links to subject and disciplinary communities as well as coherence built through links between concepts is fairly readily accessed on the Internet. The importance of information literacy for students, the critical need to curate content on the web, as well as the implications for the curriculum of framing ‘knowing’ as encompassing ‘being familiar’ and comprehending’ are highlighted. 相似文献
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An examination of recruitment materials and interviews with personnel involved in the employment of teacher educators to positions in university-based New Zealand initial teacher education (ITE) courses reveals three constructions of teacher educator as academic worker: the professional expert, the dually qualified, and the traditional academic. However, this study’s analysis shows how these constructions allow universities to pursue a bifurcated approach for the employment of teacher educators, an approach that maintains binaries within teacher education and hinders development in the field. Furthermore, as the spectre of a major cultural shift in the provision of New Zealand ITE arises, the extent to which the professional expert and traditional academic constructions of teacher educator might serve the scope of work required of postgraduate ITE going forth is questioned. 相似文献