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1.
AbstractIn an economic climate when colleges can no longer presume that legislators see institutions of higher learning as tacit public goods, institutions around the country are facing budget cuts. This article presents a case study of the experience of a mid-sized public state university and its Library in a budget crisis undergoing a university-wide program prioritization process. The authors review the process of writing three reports on the Library’s value, along with the approach to engaging staff in the process including a retreat. This article raises questions about what every library should consider assessing and provide tools for libraries navigating similar terrain. 相似文献
2.
This study explored the factors affecting repeat theatrical viewing of movies. Integrating content, social influence, and access/competition variables, the analysis reveals that the drivers of theatrical repeat viewing are different from those for box office performance. For example, the effects of genre, transmedia content, and audience review were significant only for the latter and factors such as movie length, critics’ review, and level of news coverage actually played a negative role in the repeat consumption. 相似文献
3.
Jun-Young Oh 《International Journal of Science and Mathematics Education》2011,9(5):1135-1166
Researchers have shown that most students resist changes to their core beliefs by offering auxiliary hypotheses at the first
sign of the development of conceptual change. Studies have viewed student reaction to discrepant events as an important clue
in helping researchers understand not only the structure of alternative concepts (Niaz, Science & Education, 7(2):107 – 127, 1998) but also the nature of scientific concepts. The main objectives of this research were the following: (a) to consider prudently
the conflict map of Tsai (International Journal of Science Education, 22(3):285 – 302, 2000); (b) to initiate and develop an enhanced conflict map based on Lakatosian ethodology, which could help science teachers
and students resolve conflicts that occur in the explanation of natural phenomena; (c) to examine the effectiveness of the
enhanced conflict map; and (d) to discuss these implications in science education. Specifically, this study used two freshman
classes from the Department of Electronics and one class of Astronomy majors from C. National University, South Korea, to
investigate how scientific concepts change after selecting the modern physics field (Photoelectric effect), which is included
in the Physics and Astronomy courses. Modern physics has led to the so-called Lakatosian heuristic principle or methodology,
a useful framework that includes scientific philosophy and science history as study strategies. “Enhanced conflict maps” are
suggested for use to consistently show all the study processes. 相似文献
4.
5.
An efficient method for tracing planar implicit curves 总被引:1,自引:0,他引:1
YU Zheng-sheng CAI Yao-zhi OH Min-jae KIM Tae-wan PENG Qun-sheng 《浙江大学学报(A卷英文版)》2006,7(7):1115-1123
INTRODUCTION Tracing a planar implicit curve f(x, y)=0 on a rectangular region [xl, xr]×[yb, yt] is of great interest in Computer-Aided Design and Computer Graphics. While parametric curves are easy to plot, plotting implicit curves is a challenging problem. Planar im- plicit curve plotting method can be classified into two categories (Shou et al., 2005; Martin et al., 2002; Lopes et al., 2002). In the first category are subdivi- sion methods (Shou et al., 2005; Martin et al., 2002) … 相似文献
6.
Jeong Ah Kim Hong Nam Kim Sun-Kyoung Im Seok Chung Ji Yoon Kang Nakwon Choi 《Biomicrofluidics》2015,9(2)
We present an engineered three-dimensional (3D) in vitro brain microvasculature system embedded within the bulk of a collagen matrix. To create a hydrogel template for the functional brain microvascular structure, we fabricated an array of microchannels made of collagen I using microneedles and a 3D printed frame. By culturing mouse brain endothelial cells (bEnd.3) on the luminal surface of cylindrical collagen microchannels, we reconstructed an array of brain microvasculature in vitro with circular cross-sections. We characterized the barrier function of our brain microvasculature by measuring transendothelial permeability of 40 kDa fluorescein isothiocyanate-dextran (Stoke''s radius of ∼4.5 nm), based on an analytical model. The transendothelial permeability decreased significantly over 3 weeks of culture. We also present the disruption of the barrier function with a hyperosmotic mannitol as well as a subsequent recovery over 4 days. Our brain microvasculature model in vitro, consisting of system-in-hydrogel combined with the widely emerging 3D printing technique, can serve as a useful tool not only for fundamental studies associated with blood-brain barrier in physiological and pathological settings but also for pharmaceutical applications. 相似文献
7.
Jeonghun Nam Justin Kok Soon Tan Bee Luan Khoo Bumseok Namgung Hwa Liang Leo Chwee Teck Lim Sangho Kim 《Biomicrofluidics》2015,9(6)
A novel microfluidic device which consists of two stages for particle focusing and separation using a viscoelastic fluid has been developed. A circular capillary tube was used for three-dimensional particle pre-alignment before the separation process, which was inserted in a polydimethylsiloxane microchannel. Particles with diameters of 5 and 10 μm were focused at the centerline in the capillary tube, and the location of particles was initialized at the first bifurcation. Then, 5 and 10 μm particles were successfully separated in the expansion region based on size-dependent lateral migration, with ∼99% separation efficiency. The proposed device was further applied to separation of MCF-7 cells from leukocytes. Based on the cell size distribution, an approximate size cutoff for separation was determined to be 16 μm. At 200 μl/min, 94% of MCF-7 cells were separated with the purity of ∼97%. According to the trypan blue exclusion assay, high viability (∼90%) could be achieved for the separated MCF-7 cells. The use of a commercially available capillary tube enables the device to be highly versatile in dealing with particles in a wide size range by using capillary tubes with different inner diameters. 相似文献
8.
On the Semantic Web, the types of resources and the semantic relationships between resources are defined in an ontology. By using that information, the accuracy of information retrieval can be improved. 相似文献
9.
Nam Cao Hoai Le Murat Gel Yonggang Zhu Jian Wang Helen Dacres Alisha Anderson Stephen C. Trowell 《Biomicrofluidics》2014,8(6)
Bioluminescence resonance energy transfer (BRET) is a form of Förster resonance energy transfer. BRET has been shown to support lower limits of detection than fluorescence resonance energy transfer (FRET) but, unlike FRET, has not been widely implemented on microfluidic devices for bioanalytical sensing. We recently reported a microscope-based microfluidic system for BRET-based biosensing, using a hybrid, high quantum-efficiency, form of BRET chemistry. This paper reports the first optical fiber-based system for BRET detection on a microfluidic chip, capable of quantifying photon emissions from the low quantum-efficiency BRET2 system. We investigated the effects of varying core diameter and numerical aperture of optical fibers, as well as varying microfluidic channel design and measurement conditions. We optimized the set-up in order to maximize photon counts and minimize the response time. The optimized conditions supported measurement of thrombin activity, with a limit of detection of 20 pM, which is lower than the microscope-based system and more than 20 times lower than concentrations reported to occur in plasma clots. 相似文献
10.