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971.
972.
973.
The contributions of volunteers in special libraries have not been well-documented or researched. However, anecdotal evidence shows that volunteers have played a key role in the formation of many special libraries and continue to lend their skills and knowledge to these libraries. This column explores examples from the literature and gives a brief case study on the various ways philatelic libraries use volunteers. The scope of the column includes traditional unpaid volunteers, remote volunteers, crowdsourcing, internships, job training programs, and other voluntary or nontraditional work. Volunteer labor is far from free in terms of cost to the organization, but can provide benefits beyond simply unpaid labor including subject expertise, special skills, and community building. Special libraries looking to begin or expand volunteer programs are advised to study the lessons learned from other types of libraries and organizations with successful volunteer programs. Successfully managing volunteers requires careful planning and coordination just as managing paid staff does.  相似文献   
974.
The problem of the emergence and development of documentocentrism as a theoretical and methodological approach that views a document as a basic principle is discussed.  相似文献   
975.
Librarianship has a long tradition of collaboration and cooperation between libraries, but the literature yields scant evidence of formal partnerships in practice in special libraries. This column explores the barriers to collaboration for special libraries, from organizational culture to legal constraints, as well as the potential benefits and how librarians can overcome the barriers to reap these benefits. Different types of collaboration, including among similar special libraries and between special libraries and other types of libraries and related organizations, as well as informal and formal cooperation, and short-term and long-term partnerships, are discussed. Collaboration and cooperation were part of the impetus to form professional associations. The column provides a brief history of professional library associations and their role in supporting library partnerships in the United States. The conclusion explores how the increasingly digital nature of information and library work affects collaborative library efforts and where the future of these efforts may lie, especially for special libraries.  相似文献   
976.
Financial literacy, as a concept by that name, has only been explored in library science literature for a little over a decade. The concept, and especially the role of libraries in furthering this literacy, is still evolving. This systematic literature review examines the current definition of financial literacy, why financial literacy matters, where the public has been accessing financial literacy education to date, the difficulties encountered, by libraries and others, in providing this education, and how these challenges might be addressed moving forward.  相似文献   
977.
Three librarians who have extensive experience working in libraries or for publishers, vendors, or consortia presented an informal discussion on librarian–vendor relationships. The audience was encouraged to participate. Problems were articulated; speakers and audience members contributed suggestions for better approaches or behaviors when handling difficult situations.  相似文献   
978.
We propose biofunctionalized nanofluidic slits (nanoslits) as an effective platform for real-time fluorescence-based biosensing in a reaction-limited regime with optimized target capture efficiency. This is achieved by the drastic reduction of the diffusion length, thereby a boosted collision frequency between the target analytes and the sensor, and the size reduction of the sensing element down to the channel height comparable to the depletion layer caused by the reaction. Hybridization experiments conducted in DNA-functionalized nanoslits demonstrate the analyte depletion and the wash-free detection ∼10 times faster compared to the best microfluidic sensing platforms. The signal to background fluorescence ratio is drastically increased at lower target concentrations, in favor of low-copy number analyte analysis. Experimental and simulation results further show that biofunctionalized nanoslits provide a simple means to study reaction kinetics at the single-pixel level using conventional fluorescence microscopy with reduced optical depth.  相似文献   
979.
The flow focusing is a fundamental prior step in order to sort, analyze, and detect particles or cells. The standard hydrodynamic approach requires two fluids to be injected into the microfluidic device: one containing the sample and the other one, called the sheath fluid, allows squeezing the sample fluid into a narrow stream. The major drawback of this approach is the high complexity of the layout for microfluidic devices when parallel streams are required. In this work, we present a novel parallelized microfluidic device that enables hydrodynamic focusing in each microchannel using a single feed flow. At each of the parallel channels, a cross-filter region is present that allows removing fluid from the sample fluid. This fluid is used to create local sheath fluids that hydrodynamically pinch the sample fluid. The great advantage of the proposed device is that, since only one inlet is needed, multiple parallel micro-channels can be easily introduced into the design. In the paper, the design method is described and the numerical simulations performed to define the optimal design are summarized. Moreover, the operational functionality of devices tested by using both polystyrene beads and Acute Lymphoid Leukemia cells are shown.  相似文献   
980.
Creating multicellular tumor spheroids is critical for characterizing anticancer treatments since they may provide a better model of the tumor than conventional monolayer culture. Moreover, tumor cell interaction with the extracellular matrix can determine cell organization and behavior. In this work, a microfluidic system was used to form cell-laden core-shell beads which incorporate elements of the extracellular matrix and support the formation of multicellular spheroids. The bead core (comprising a mixture of alginate, collagen, and reconstituted basement membrane, with gelation by temperature control) and shell (comprising alginate hydrogel, with gelation by ionic crosslinking) were simultaneously formed through flow focusing using a cooled flow path into the microfluidic chip. During droplet gelation, the alginate acts as a fast-gelling shell which aids in preventing droplet coalescence and in maintaining spherical droplet geometry during the slower gelation of the collagen and reconstituted basement membrane components as the beads warm up. After droplet gelation, the encapsulated MCF-7 cells proliferated to form uniform spheroids when the beads contained all three components: alginate, collagen, and reconstituted basement membrane. The dose-dependent response of the MCF-7 cell tumor spheroids to two anticancer drugs, docetaxel and tamoxifen, was compared to conventional monolayer culture.  相似文献   
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