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991.
BusinessThinkingTM is a computer-based e-learning package designed to teach technology skills and business information to adults, ages 50–69, who remain in the workforce. This article outlines results from usability testing for the material on using technology applications (Microsoft Word, PowerPoint, Excel and the Internet), and career development (career management and preretirement planning. In Study 1, a usability test was conducted to ensure that the material was user-friendly. In Studies 2 and 3, the PowerPoint and career development materials were redesigned according to the findings from Study 1. Results indicated that the redesign was effective in increasing navigation of the material. 相似文献
992.
In order to meet both in‐service and pre‐service training needs in gerontology, North Country Community College has developed an innovative one‐year certificate program. Under the assumption that persons working with the aged in a rural area must have a diverse group of skills to draw upon, the gerontology certificate stresses course work in: communication skills, culture variability, gerontology knowledge, management skills, and service skills. The curriculum approach taken is that of competency based education, with most of the skills courses put into a modular course format. After the first year of the certificate, 53% (N = 65) of the students in the certificate courses are adults or community professionals turning to this community college program to upgrade skills or acquire new ones. This certificate is beginning to meet the training needs in a rural area that were only previously addressed by occasional workshops for the human service practitioner. 相似文献
993.
Jason L.G. Braasch Ivar BråtenHelge I. Strømsø Øistein AnmarkrudLeila E. Ferguson 《Contemporary educational psychology》2013
The current research examined whether instructional activities centering on contrasting cases promoted secondary school students’ evaluations of source features present in a multiple-documents inquiry context. Two hypothetical students’ document evaluation strategy protocols were designed: One featured more sophisticated strategies commonly enacted by experts and better college students and a second featured less sophisticated strategies commonly enacted by secondary school students. A series of classroom-based activities required that students compare/contrast the two protocols to decide which were the best strategies when analyzing multiple scientific documents and why. The findings demonstrated that students who previously participated in the intervention activities included more scientific concepts from more useful documents when generating essay responses from memory, displayed better rankings of the usefulness of the set of multiple documents, and offered more principled justifications based on source feature evaluations of trustworthiness compared to students who instead received typical classroom instruction. We discuss the instructional implications of a contrasting-cases approach in facilitating secondary school students’ usage of source features within multiple-documents inquiry contexts. 相似文献
994.
The World Wide Web is a popular “tool” for companies. It can be used as a method of communication between companies and their customers; it also allows organizations to setup virtual storefronts that can be accessed by customers from all over the world. The ability to understand customers’ behavior is extremely important as companies strive to increase the usability and profitability of their web service. The concept of a session is a popular unit of measurement used to analyze recorded information. However, this concept is currently rather abstract and lacks definition. How we measure a session is a fundamental question for web services utilizing this concept. Currently, this question has no real answer. This paper presents a session timeout threshold model based on empirical observations as an initial answer to this question. The model seeks to provide accurate session data with respect to individual web services. 相似文献
995.
Early research on the social implications of e-mail has promoted the role of electronic communication channels in fostering social equality and reducing gaps between the social classes. Follow-up studies, however, suggest that people continue to rely on social cues in electronic communication as a way of dealing with uncertainties and reducing feelings of discomfort associated with unfamiliar contexts. Based on a review of the Social Cognitive Theory, social status and electronic communication literatures, along with the results of a previous qualitative study, we propose a formal model that indicates how self-perceptions of social status are related to the use of e-mail and the acquisition of social resources over electronic channels. The model is tested using data collected from 206 faculty members in a major U.S. university. The empirical results support the proposed model implying that self-perceptions of social status influence social assertiveness, which in turn reinforces the use of e-mail to seek help and acquire social resources from others. The use of e-mail for the acquisition of social resources is associated with a socially diverse network whose contacts are perceived to acquire valuable information and to extend instrumental support for career development. Implications are drawn for both theory and practice. 相似文献
996.
Ultrafast microfluidics using surface acoustic waves 总被引:2,自引:0,他引:2
We demonstrate that surface acoustic waves (SAWs), nanometer amplitude Rayleigh waves driven at megahertz order frequencies propagating on the surface of a piezoelectric substrate, offer a powerful method for driving a host of extremely fast microfluidic actuation and micro∕bioparticle manipulation schemes. We show that sessile drops can be translated rapidly on planar substrates or fluid can be pumped through microchannels at 1–10 cm∕s velocities, which are typically one to two orders quicker than that afforded by current microfluidic technologies. Through symmetry-breaking, azimuthal recirculation can be induced within the drop to drive strong inertial microcentrifugation for micromixing and particle concentration or separation. Similar micromixing strategies can be induced in the same microchannel in which fluid is pumped with the SAW by merely changing the SAW frequency to rapidly switch the uniform through-flow into a chaotic oscillatory flow by exploiting superpositioning of the irradiated sound waves from the sidewalls of the microchannel. If the flow is sufficiently quiescent, the nodes of the transverse standing wave that arises across the microchannel also allow for particle aggregation, and hence, sorting on nodal lines. In addition, the SAW also facilitates other microfluidic capabilities. For example, capillary waves excited at the free surface of a sessile drop by the SAW underneath it can be exploited for micro∕nanoparticle collection and sorting at nodal points or lines at low powers. At higher powers, the large accelerations off the substrate surface as the SAW propagates across drives rapid destabilization of the drop free surface giving rise to inertial liquid jets that persist over 1–2 cm in length or atomization of the entire drop to produce 1–10 μm monodispersed aerosol droplets, which can be exploited for ink-jet printing, mass spectrometry interfacing, or pulmonary drug delivery. The atomization of polymer∕protein solutions can also be used for the rapid synthesis of 150–200 nm polymer∕protein particles or biodegradable polymeric shells in which proteins, peptides, and other therapeutic molecules are encapsulated within for controlled release drug delivery. The atomization of thin films behind a translating drop containing polymer solutions also gives rise to long-range spatial ordering of regular polymer spots whose size and spacing are dependent on the SAW frequency, thus offering a simple and powerful method for polymer patterning without requiring surface treatment or physical∕chemical templating. 相似文献
997.
We present a straightforward and rapid surface acoustic wave (SAW) atomization-based technique for encapsulating proteins into 10 μm order particles composed of a biodegradable polymeric excipient, using bovine serum albumin (BSA) as an exemplar. Scans obtained from confocal microscopy provide qualitative proof of encapsulation and show the fluorescent conjugated protein to be distributed in a relatively uniform manner within the polymer shell. An ELISA assay of the collected particles demonstrates that the BSA survives the atomization, particle formation, and collection process with a yield of approximately 55%. The SAW atomization universally gave particles with a textured morphology, and increasing the frequency and polymer concentration generally gave smaller particles (to 3 μm average) with reduced porosity. 相似文献
998.
Rani James K. Thriveni Girija Ramaswamy Lakshmi Krishnamoorthy Geetashree Mukherjee P. P. Vijayalaxmi Deshmane P. P. Bapsy 《Indian journal of clinical biochemistry : IJCB》2008,23(4):345-351
HER-2 is overexpressed in approximately 20–30% of invasive Breast Cancer. ECD of the HER-2 protein is frequently cleaved and
released into the circulation, where it can be detected by ELISA in up to 45% of patients with metastatic breast cancer. The
objective of our study was to compare the current methods for the detection of HER-2 protein. Tissue HER-2 levels were studied
in 100 breast cancer patients by IHC and compared with serum HER-2 levels by ELISA. IHC frequency was 29%. Serum HER-2 ECD
was positive in 42% of patients. A statistically significant correlation was observed. HER-2 detected by IHC correlates significantly
with serum HER-2 levels detected by ELISA. Thus, ELISA is a reliable and economical tool to assess the HER-2 status in tumors,
when breast tissue sample is not available. 相似文献
999.
This paper discusses the role of public demand, in the form of a government procurement policy, in generating innovative solutions for healthcare infrastructure. It considers the effects of the project delivery system (planning, finance, construction and operation) for new hospitals on design innovation. It focuses on hospitals built under the UK's private finance initiative (PFI), which was partly introduced to inject increased innovation into hospital delivery. We use case studies of six early PFI hospitals to argue that the introduction of PFI has increased the complexity at the interface between project delivery and hospital operational functions. The result is a project delivery model which yields less innovative outcomes and produces facilities that might not be able to cope with future changes in demand. The paper suggests that new public procurement models do not automatically provide efficiency and innovation benefits. 相似文献
1000.
Although the need for personal counseling services is on the rise across college campuses in the United States, many community colleges do not offer personal counseling services on campus. Instead, community college counseling services focus primarily on academic and career advising. The purpose of this study was to survey community college students in North Carolina to determine their interest in and need for a personal counseling center on campus. Participants were 134 men and 202 women, 18–68 years of age. Of the participants, 70% indicated that having a personal counseling center on campus would be “very helpful” or “helpful.” Results are discussed, and recommendations are made for college counselors working in community college settings. 相似文献