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Small Cell Size (small + cell_size)
Selected AbstractsA Low-Temperature-Grown Oxide Diode as a New Switch Element for High-Density, Nonvolatile Memories,ADVANCED MATERIALS, Issue 1 2007M.-J. Lee A one-diode/one-resistor structure, Pt/NiO/Pt/p-NiOx/n-TiOx/Pt, has been fabricated. This novel structure exhibits bistable resistance switching under forward bias, while the diode suppresses resistance switching in the Pt/NiO/Pt memory cell under reverse bias (see figure). Its low processing temperature and small cell size, as well as excellent rectifying characteristics, make this Pt/p-NiOx/n-TiOx/Pt diode structure a promising switch element for high- density, nonvolatile memory devices with 3D stack and cross-point structures. [source] Enabling location-based services in wireless LAN hotspotsINTERNATIONAL JOURNAL OF NETWORK MANAGEMENT, Issue 3 2005Yen-Cheng Chen The wide deployment of IEEE 802.11 Wireless LAN (WLAN) makes possible application services developed in WLAN hotspots. Owing to the small cell size in WLAN hotspots, it is practical to develop location-based services with the awareness of the WLAN access points (APs) that mobile devices currently access. In this paper, we propose an effective location determination technique using the inherent SNMP support in WLAN APs. It is shown that the current location of a mobile device can be determined from the SNMP traps sent by APs. Since the SNMP-based approach doesn't need any particular software or hardware in mobile devices, location-based services can be widely deployed, especially in public WLAN hotspots. To further enable location-based services through the WWW, this paper also considers the location determination of a mobile device from its IP address, retrieved in a WWW environment. In addition, we propose a web service framework for location-based services in WLAN hotspots. Thus, location-based services can be developed in a standard way.,Copyright © 2005 John Wiley & Sons, Ltd. [source] Design, process, and performance of all-epitaxial normally-off SiC JFETsPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 10 2009Rajesh K. Malhan Abstract This paper reviews the normally-off (N - off) and normally-on (N - on) SiC junction field effect transistor (JFET) concepts and presents an innovative all-epitaxial double-gate trench JFET (DGTJFET) structure. The DGTJFET design combines the advantages of lateral and buried gate JFET concepts. The lateral JFET advantage is the epitaxial definition of the channel width and the buried gate JFET advantage is the small cell size. In the DGTJFET process the epitaxial embedded growth in trenches facilitates the small cell pitch and the vertical direction of the channel. A detailed numerical simulation analysis compares the potential of the DGTJFET design with reported lateral channel and buried gate JFET structures. Migration enhanced embedded epitaxy (ME3) and planarization processes were developed to realize narrow cell pitch DGTJFETs for high-density power integration. The highly doped vertical channel of the DGTJFET defined by the ME3 growth process makes it possible to accurately control the sub-micron channel dimensions in order to realize a low specific on-state resistance (RON) and a high saturation current capability. The anisotropic nature of SiC is taken into account for the channel design considerations. The successful application of the new process technologies for the development of the all-epitaxial DGTJFETs is discussed. Fabricated 5.5 ,m cell pitch 4H-SiC DGTJFETs demonstrate the saturation current density capability of more than 1000 A/cm2. N - off and N - on DGTJFETs with 2.25 mm squared chip size and 9.5 ,m cell pitch output 15 A and 20 A at gate voltage of 2.5 V and drain voltage of 5.0 V. The specific RON of the N - off and N - on DGTJFETs is at room temperature 8.1 m , cm2 and 6.3 m, cm2, respectively, indicating that N - off devices can be realized at the expense of a slight increase in specific RON of approximately 25%. DGTJFETs with a 13 ,m drift layer doped to 5.0 × 1015 cm,3 are demonstrated with a breakdown voltage in the range of 1200 V to 1550 V at the wafer level with a leakage current below 10 ,A. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Tobacco BY-2 cells expressing fission yeast cdc25 bypass a G2/M block on the cell cycleTHE PLANT JOURNAL, Issue 2 2005Craig B. Orchard Summary The mitotic inducer gene from Schizosaccharomyces pombe, Spcdc25, was used as a tool to investigate regulation of G2/M in higher plants using the BY-2 (Nicotiana tabacum) cell line as a model. Spcdc25 -expressing BY-2 cells exhibited a reduced mitotic cell size through a shortening of the G2 phase. The cells often formed isodiametric double files both in BY-2 cells and in cell suspensions derived from 35S::Spcdc25 tobacco plants. In Spcdc25 -expressing cells, the tobacco cyclin-dependent kinase, NtCDKB1, showed high activity in early S phase, S/G2 and early M phase, whereas in empty vector cells CDKB1 activity was transiently high in early S phase but thereafter remained lower. Spcdc25- expressing cells also bypassed a block on G2/M imposed by the cytokinin biosynthetic inhibitor lovastatin (LVS). Surprisingly, cytokinins were at remarkably low levels in Spcdc25 -expressing cells compared with the empty vector, explaining why these cells retained mitotic competence despite the presence of LVS. In conclusion, synchronised Spcdc25 -expressing BY-2 cells divided prematurely at a small cell size, and they exhibited premature, but sustained, CDKB1 activity even though endogenous cytokinins were virtually undetectable. [source] Cytopathologic differential diagnosis of small cell carcinoma and poorly differentiated non-small cell carcinoma in bronchial lavage specimens using a regression analysisAPMIS, Issue 2 2010EBRU CAKIR Cakir E, Demirag F, Aydin M. Cytopathologic differential diagnosis of small cell carcinoma and poorly differentiated non-small cell carcinoma in bronchial lavage specimens using a regression analysis. APMIS 2010; 118: 150,55. The aim of this study was to determine the most significant cytologic features to differentiate small cell carcinoma (SCC) from poorly differentiated non-small cell carcinoma (NSCC) in bronchial lavage specimens. Bronchial lavage specimens from 35 SCC cases and 63 poorly differentiated NSCC cases were examined and the cytologic parameters reviewed retrospectively. Thirty-five cytologic features considered useful in differential diagnosis were assessed. Statistical analysis indicated that salt and pepper chromatin, small cell size and nuclear molding have more than 90% sensitivity and 70% specificity for SCC cases. Logistic regression analysis demonstrated that the most effective criteria to differentiate SCC from poorly differentiated NSCC are small cell size, salt and pepper chromatin, prominent nucleolus and papilla formation. When these selected variables were used, sensitivity for predicting SCC was 94.3% and specificity 96.8%, and sensitivity for predicting NSCC was 96.8% and specificity 94.3%. There are several cytologic features, which are highly sensitive and specific for distinguishing SCC from NSCC. Nuclear features such as chromatin pattern, and size of the nucleoli and nuclei are more valuable than cytoplasmic features to distinguish between the two. [source] Unwanted sexual advances at work: variations by employment arrangement in a sample of working AustraliansAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 2 2009Anthony D. LaMontagne Abstract Objective: We tested the hypothesis that the risk of experiencing unwanted sexual advances at work (UWSA) is greater for precariously-employed workers in comparison to those in permanent or continuing employment. Methods: A cross-sectional population-based telephone survey was conducted in Victoria (66% response rate, N=1,101). Employment arrangements were analysed using eight differentiated categories, as well as a four-category collapsed measure to address small cell sizes. Self-report of unwanted sexual advances at work was modelled using multiple logistic regression in relation to employment arrangement, controlling for gender, age, and occupational skill level. Results: Forty-seven respondents reported UWSA in our sample (4.3%), mainly among women (37 of 47). Risk of UWSA was higher for younger respondents, but did not vary significantly by occupational skill level or education. In comparison to Permanent Full-Time, three employment arrangements were strongly associated with UWSA after adjustment for age, gender, and occupational skill level: Casual Full-Time OR = 7.2 (95% Confidence Interval 1.7-30.2); Fixed-Term Contract OR = 11.4 (95% CI 3.4-38.8); and Own-Account Self-Employed OR = 3.8 (95% CI 1.2-11.7). In analyses of females only, the magnitude of these associations was further increased. Conclusions: Respondents employed in precarious arrangements were more likely to report being exposed to UWSA, even after adjustment for age and gender. Implications: Greater protections from UWSA are likely needed for precariously employed workers. [source] | ||||||||||