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排序方式: 共有163条查询结果,搜索用时 10 毫秒
1.
Despite much research interest, effective retention of IT professionals has proved difficult for many public sector organizations. By concentrating on intention to leave, researchers may not have provided a clear way to formulate effective retention strategies. Consequently, we used intention to stay as an alternative lens to identify factors that can reduce turnover of IT professionals. Our findings indicated that attitudes, perceived behavioral control (PBC), and identification with the organization all had a statistically significant relationship with intention to stay; attitude was the strongest. It was concluded that existing retention strategies needed to be refocused on the issues that make IT staff stay; a number of practical recommendations for IT managers are presented.  相似文献   
2.
In recent years, considerable attention has been paid to enterprise information systems. This interest is motivated by the need for achieving better integration of new technologies (hardware and software) with the business processes of an organization. Business processes have become more and more dependent on technologies because technology has a direct impact on business processes, changing the way they are performed and thus also affecting the way analysts design the software system. However, at the present time, there are still some gaps between the definition of business processes and the technologies used in the organization. In practice, organizations have carried out their business processes using different technologies; however, it is sometimes not possible to determine how technologies are useful in achieving current business goals. This is because business models do not explicitly consider the technologies in the organizational requirements. The goal of this paper is to present a systematic process for integrating business processes and technologies at the conceptual level. To validate our approach, we present a case study that describes the processes of the inventory management department of a public research center.  相似文献   
3.
"Full veneers," restorations similar in depth to ceramic veneers but extending over the lingual or occlusal surface as well as the facial surface, are a conservative option to conventional crowns. They have been used successfully at the UCLA Center for Esthetic Dentistry for three years. Indications, technique and a patient study are presented.  相似文献   
4.
Sensors for monitoring temperature, heat flux, and thermal radiation are essential for applications such as electronic skin. While pyroelectric and thermoelectric effects are suitable candidates as functional elements in such devices, both concepts show individual drawbacks in terms of zero equilibrium signals for pyroelectric materials and small or slow response of thermoelectric materials. Here, these drawbacks are overcome by introducing the concept of thermodiffusion‐assisted pyroelectrics, which combines and enhances the performance of pyroelectric and ionic thermoelectric materials. The presented integrated concept provides both rapid initial response upon heating and stable synergistically enhanced signals upon prolonged exposure to heat stimuli. Likewise, incorporation of plasmonic metasurfaces enables the concept to provide both rapid and stable signals for radiation‐induced heating. The performance of the concept and its working mechanism can be explained by ion–electron interactions at the interface between the pyroelectric and ionic thermoelectric materials.  相似文献   
5.
ABSTRACT

Deoxyribozymes (DNAzymes) are DNA residue-based molecules capable of specific cleavage of complementary mRNA. As such, they are more stable counterparts for the earlier discovered ribozymes. A handful of studies have shown the potential of DNAzymes against cancer both in cell culture and importantly in vivo models. This relatively new molecular entity may progress to clinical trials provided that more extensive testing is carried out at the preclinical stage. While a significant amount of work has gone into chemically stabilizing the molecule, delivery is one area that needs particular attention.  相似文献   
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7.
This paper examines the sensitivity to change over time of the Amyotrophic Lateral Sclerosis Assessment Questionnaire (ALSAQ-40). Individuals' health status change was assessed by means of the Rasch-based Reliable Change Index (RCI) for ALSAQ-40 questionnaires completed on two occasions, three months apart. In addition, at follow-up respondents indicated how much change they had experienced since baseline via dimension-specific self reported transition questions. 764 individuals returned questionnaires at baseline and follow-up. For all dimensions, of respondents defined by the RCI as worse, a majority rated themselves as worse. However, on two dimensions over 60% of the respondents who rated themselves as being worse were defined as unchanged by the RCI. As with effect size smaller RCI cut-off points might be needed for subjects with ALS. This study confirms that the ALSAQ-40 is a valid and responsive disease specific health related quality of life instrument for use in studies of patients with ALS or other motor neuron diseases.  相似文献   
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9.
Kim K  Moon T  Kim J  Kim S 《Nanotechnology》2011,22(24):245203
Electrically driven lasing was demonstrated in light-emitting devices composed of n-ZnO and p-Si nanowires (NWs). The ZnO NWs were synthesized by thermal chemical vapor deposition and the Si NWs were formed by crystallographic wet etching of a Si wafer. The p-n heterojunction devices were constructed using the NWs by the direct transfer and dielectrophoresis methods. At an excitation current of 2 μA, the electroluminescence spectrum showed lasing behavior, and this phenomenon was explained by the ZnO-nanostructure-related cavity property.  相似文献   
10.
STATEMENT OF PROBLEM: The practice of fixed prosthodontic has changed dramatically with the introduction of innovative techniques and materials. Adhesive resin systems are examples of these changes that have led to the popularity of bonded ceramics and resin-retained fixed partial dentures. Today's dentist has the choice of a water-based luting agent (zinc phosphate, zinc polycarboxylate, glass ionomer, or reinforced zinc oxide-eugenol) or a resin system with or without an adhesive. Recent formulations of glass ionomer luting agents include resin components (resin-modified glass ionomers), which are increasingly popular in clinical practice. PURPOSE: This review summarizes the research on these systems with the goal of providing information that will help the reader choose the most suitable material. MATERIAL: The scientific studies have been evaluated in relation to the following categories: (1) biocompatibility, (2) caries or plaque inhibition, (3) microleakage, (4) strength and other mechanical properties, (5) solubility, (6) water sorption, (7) adhesion, (8) setting stresses, (9) wear resistance, (10) color stability, (11) radiopacity, (12) film thickness or viscosity, and (13) working and setting times. In addition, guidelines on luting-agent manipulation are related to available literature and include: (1) temporary cement removal, (2) smear layer removal, (3) powder/liquid ratio, (4) mixing temperature and speed, (5) seating force and vibration, and (6) moisture control. Tables of available products and their properties are also presented together with current recommendations by the authors with a rationale.  相似文献   
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