Medical and Societal information from the Research Community	Number of Articles: 17,750,454 Number of Contributors: 57 Number of Queries: 12,899,077
	Save this page:  Send this page	Login  or Create a Free Account

GST Primary GST Primary Best Strategies for Health Care Quality Im... Best Strategies for Health Care Quality Improvement - Diabetes Quality Improvement Strategies for Antibio... Kathryn McDonald, Stanford-UCSF Evidence-b... Systematic review assessing the effect of ... Quality Improvement Strategies for Antibiotics Management Kathryn McDonald, Stanford-UCSF Evidence-based Practice Center, 117 Encina Commons, Stanford, CA 94305-6019, Kathy.mcdonald@stanford.edu Systematic review assessing the effect of quality improvement strategies on appropriate prescribing of antibiotics and appropriate choice of antibiotics. Adherence Adherence Assistive Devices Assistive Devices Childhood Burn Hanson MacMillan Childhood Burn Hanson MacMillan CLSA_9 CLSA_9 Cyberabuse Cyberabuse Cognitive Behavioural Therapy for Violent ... This review included randomized trials abo... Cognitive Behavioural Therapy for Violent Men who Batter Their Partners This review included randomized trials about the effects of cognitive behavioral therapy on domestic violence. The intervention included programs based on the Duluth Model. The violence had to be committed by a male toward his female partner. The violence also had to be physical. The primary outcomes were new arrests and convictions, and new reports of violence. CABG vs PCI CABG vs PCI Quality Improvement Strategies for Prevent... Quality Improvement Strategies for Preventing Nosocomial Infections (Created 17-Feb-06) Quality Improvement Strategies for Asthma ... Quality Improvement Strategies for Asthma Control Erectile Dysfunction (Created 30-Jan-06) Erectile Dysfunction (Created 30-Jan-06) Inequality - Smoking Cessation to Reduce S... This review was the first part of a projec... Inequality - Smoking Cessation to Reduce Socio-Economic Differences This review was the first part of a project about inequality. It included randomized trials about the effect of smoking cessation interventions on reducing socio-economic differences. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Diet and Physical Activity to Reduce Socio... This review was the second part in a proje... Diet and Physical Activity to Reduce Socio-Economic Differences This review was the second part in a project about inequality. It included randomized trials about the effect of interventions on reducing socio-economic differences in diet and physical activity. The studies had to report data either on persons with low socio-economic groups status or, preferably, on both low and high socio-economic groups. Workfare The data in SRS are not identical to the d... Workfare The data in SRS are not identical to the data in the published report. We used SRS only for an updated search. The review included randomized trials about the effect of welfare-to-work programs. Participants were welfare recipients. There were basically two types of programs. The educational type tried to build knowledge and skills in order to help the welfare recipients acquire jobs that could support them economically. The "work first" approach was more aimed at getting the participants quickly into a job. Exercise interventions for the management ... The objective of this systematic review wa... Exercise interventions for the management of frailty The objective of this systematic review was to examine the effectiveness of current exercise interventions on the management of frailty. A comprehensive search of Medline, Embase, Psycinfo, Cinahl, Scopus, Ageline, Eric, and SportDiscus databases was conducted and produced 1808 citations. So far we have completed 2 levels of “title and abstract” screening and we ended up with 262 articles. We have just started the full text screening. Eligibility criteria included original studies whose participants were identified as frail or prefrail with specific criteria and in which structured physical activity was included as at least one component of the intervention. Create a free account, build a dictionary with saved terms to re-use later! Public Domestic Violence - Using Cognitive Behavior Therapy Smoking Cessation to Reduce Socio-Economic Differences Diet and Physical Activity to Reduce Socio-Economic Differences Workfare Exercise Interventions for the Management of Frailty Search     Simple Advanced Refine (4 coded questions)  Any of these:   Exact Phrase: All of these: None of these: Author: Periodical: Projects: No restrictions   Libraries: Public   Select SRS Projects Show Saved Terms Select Library Show articles that do not have abstracts  Type of Article Clinical Trial Editorial Letter Meta-Analysis Practice Guideline Randomized Controlled Trial Review Addresses Bibliography Biography Case Reports Classical Article Clinical Conference Clinical Trial, Phase I Clinical Trial, Phase II Clinical Trial, Phase III Clinical Trial, Phase IV Comment Comparative Study Consensus Development Conference Consensus Development Conference, NIH Controlled Clinical Trial Corrected and Republished Article Dictionary Directory Duplicate Publication English Abstract Evaluation Studies Festschrift Government Publications Guideline Historical Article Interview In Vitro Journal Article Lectures Legal Cases Legislation Multicenter Study News Newspaper Article Overall Patient Education Handout Periodical Index Published Erratum Retracted Publication Research Support, N.I.H., Extramural Research Support, N.I.H., Intramural Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. Research Support, U.S. Gov't, P.H.S. Retraction of Publication Scientific Integrity Review Support of Research Technical Report Twin Study Validation Studies Not a Primary Study or Review Unknown Primary Study Case Series Case Control Cohort Study Observational Study Qualitative Research CBA or ITS Registry Double Blind Controlled before after study Quasi-randomized trial Simple before after study Cluster-RCT Non-Randomized Study Report Book Book chapter Dissertation Conference procedings Secondary Research Not RCT Humans or Animals Humans Animals Ages All Infant: birth-23 months All Child: 0-18 years All Adult: 19+ years Newborn: birth-1 month Infant: 1-23 months Preschool Child: 2-5 years Child: 6-12 years Adolescent: 13-18 years Adult: 19-44 years Middle Aged: 45-64 years Middle Aged + Aged: 45+ years Aged: 65+ years 80 and over: 80+ years Undetermined Language English French German Italian Japanese Russian Spanish Afrikaans Albanian Unknown Arabic Armenian Azerbaijani Bosnian Bulgarian Catalan Chinese Croatian Czech Danish Dutch Esperanto Estonian Finnish Georgian Greek, Modern Hebrew Hindi Hungarian Icelandic Indonesian Kinyarwanda Korean Latin Latvian Lithuanian Macedonian Malay Malayalam Maori Multiple Languages Norwegian Persian Polish Portuguese Pushto Romanian Sanskrit Scottish gaelic Serbian Slovak Slovenian Swedish Thai Turkish Ukrainian Vietnamese Not English Not French Results(1-25 of 36) Sort By: Publication Date Relevance Took: 0.412 seconds to search 17,750,454  Action: Copy Results to new Clipboard Build Search Link Page 1 of 2 1 2 > (36 articles found) Novel index-guided photonic crystal fiber surface-enhanced Raman scattering probe. May 26, 2008 He Yan,Jie Liu,Changxi Yang,Guofan Jin,Claire Gu,Lantian Hou We demonstrate a novel index-guided (IG) photonic crystal fiber (PCF) surface-enhanced Raman probe. Different from a regular PCF, the IGPCF has four big air holes inserted between the solid silica core and the photonic crystal cladding holes. The gold nanoparticles, serving as the surface enhanced ... ( view more )Raman scattering (SERS) substrate, are either coated on the inner surface of the holes or mixed in the analyte solution in two separate experiments, respectively. The analyte solution enters the holes via the capillary effect. The excitation light propagating in the silica core interacts with the gold nanoparticles and the analyte through the evanescent wave which extends significantly into the four big holes when they are filled with liquid leading to a large interaction volume between the excitation light and the nanoparticles/analyte. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Phase-modulated multigroup volume holographic correlator. May 15, 2008 Kai Ni,Wei Ren,Zongyao Qu,Liangcai Cao,Qingsheng He,Guofan Jin We propose a hybrid multiplexing method for volume holographic correlators based on the combination of orthogonal random phase modulation of an object beam and two-dimensional angular multiplexing of a reference beam. This method implements storing multiple groups of library images in a single stor... ( view more )age location and outputting multiple groups of correlation spots by switching the modulation phase masks. Three experiments are designed to test the validity of this method. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles The phase shift index for marking functional asynchrony in Alzheimer's disease patients using fMRI. Apr 2008 Yin Xu,Guofan Xu,Gaohong Wu,Piero Antuono,Daniel B Rowe,Shi-Jiang Li Our previous study suggested that the functional magnetic resonance imaging MRI (fMRI) COSLOF Index (CI) could be used as a quantitative biomarker for Alzheimer's disease (AD). The fMRI CI was lowest in the AD group (0.13+/-0.10), followed by the mild cognitive impairment (MCI) group (0.20+/-0.05) ... ( view more )and the control group (0.34+/-0.09). The current study continues an investigation into which of the following two factors has a dominant role in determining the CI: the signal-to-noise ratio (SNR) or the phase shift of spontaneous low-frequency (SLF) components. By using a theoretical model for SLF components, we demonstrated that the normalized CI does not depend on the SNR of the SLF components. Further analysis shows that by taking the ratio of the cross-correlation coefficient to the maximum-shifted cross-correlation coefficient, the SNR factor can be canceled. Therefore, the determination of the phase shift index (PSI) method is independent of the SNR, and the PSI provides an accurate measure of the phase shift between SLF components. By applying this PSI method to the control, MCI and AD groups of subjects, experimental results demonstrated that the PSI was highest in the AD group (72.6+/-11.3 degrees ), followed by the MCI group (58.6+/-5.7 degrees ) and, finally, the control group (40.6+/-8.4 degrees ). These results suggest that the larger is the PSI value, the more asynchrony exists between SLF components. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Improving accuracy of multichannel volume holographic correlators by using a two-dimensional interleaving method. Oct 15, 2007 Kai Ni,Zongyao Qu,Liangcai Cao,Ping Su,Qingsheng He,Guofan Jin We introduce a two-dimensional interleaving method to improve the output accuracy of volume holographic correlators. The method redistributes the pattern of every input and stored image without changing their inner products, so it can eliminate the impact of correlation pattern difference on calcul... ( view more )ated inner product values. Experimental tests show that this method can achieve more accurate output intensity for every channel, which agrees much better with the theoretical value than without this method. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Hybrid iterative phase retrieval algorithm based on fusion of intensity information in three defocused planes. Oct 1, 2007 Fa Zeng,Qiaofeng Tan,Yingbai Yan,Guofan Jin Study of phase retrieval technology is quite meaningful, for its wide applications related to many domains, such as adaptive optics, detection of laser quality, precise measurement of optical surface, and so on. Here a hybrid iterative phase retrieval algorithm is proposed, based on fusion of the i... ( view more )ntensity information in three defocused planes. First the conjugate gradient algorithm is adapted to achieve a coarse solution of phase distribution in the input plane; then the iterative angular spectrum method is applied in succession for better retrieval result. This algorithm is still applicable even when the exact shape and size of the aperture in the input plane are unknown. Moreover, this algorithm always exhibits good convergence, i.e., the retrieved results are insensitive to the chosen positions of the three defocused planes and the initial guess of complex amplitude in the input plane, which has been proved by both simulations and further experiments. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles COmplex-Model-Based Estimation of thermal noise for fMRI data in the presence of artifacts. Sep 2007 Yin Xu,Gaohong Wu,Daniel B Rowe,Yuan Ma,Rongyan Zhang,Guofan Xu,Shi-Jiang Li Due to the presence of artifacts induced by fast-imaging acquisition in functional magnetic resonance imaging (fMRI) studies, it is very difficult to estimate the variance of thermal noise by traditional methods in magnitude images. Moreover, the existence of incidental phase fluctuations impairs t... ( view more )he validity of currently available solutions based on complex datasets. In this article, a time-domain model is proposed to generalize the analysis of complex datasets for nonbrain regions by incorporating artifacts and phase fluctuations. Based on this model, a novel estimation schema has been developed to find an appropriate set of voxels in nonbrain regions according to their levels of artifact and phase fluctuation. In addition, noise intensity from these voxels is estimated. The whole schema is named COmplex-Model-Based Estimation (COMBE). Theoretical and experimental results demonstrate that the proposed COMBE method provides a better estimation of thermal noise in fMRI studies compared with previously proposed methods and suggest that the new method can adapt to a broader range of applications, such as functional connectivity studies, evaluation of sequence designs and reconstruction schemas. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Simultaneous defocusing of the aperture and medium on a spectroholographic storage system. Aug 10, 2007 Zhuo Wang,Guofan Jin,Qingsheng He,Minxian Wu In a spectroholographic storage system the defocusing method is often used to obtain spectrum uniformity and improve the quality of the recorded information. However, defocusing introduces vignette and stronger interpixel cross talk in the marginal field of view. We report a method that defocuses t... ( view more )he aperture and medium together. Based on the pixel spread function, two inequalities are introduced to estimate the upper and lower bounds of the energy received at the CCD. We balance the spectrum uniformity with interpixel cross talk and vignette and then allow the designer to select optimal structure values of the defocusing spectroholographic storage system, i.e., the defocusing value, aperture size, and fill factors for the spatial light modulator and CCD. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Resolution enhancement by combination of subpixel and deconvolution in miniature spectrometers. Jun 1, 2007 Li Xu,Huaidong Yang,Kexin Chen,Qiaofeng Tan,Qingsheng He,Guofan Jin The resolution of a miniature spectrometer with a multichannel detector is limited by its throughput. A subpixel deconvolution method is proposed to enhance resolution without physically reducing the throughput. The method introduces subpixel reconstruction to overcome undersampling during deconvol... ( view more )ution processing. The experimental result has shown a 36.6% reduction in FWHM of spectral lines, indicating the effectiveness of the method. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles A new scheme of hybridization based on the Au(nano)-DNA modified glassy carbon electrode. May 15, 2007 Jingwan Kang,Xiaoning Li,Guofan Wu,Zhihua Wang,Xiaoquan Lu DNA hybridization on the Au(nano)-DNA modified glassy carbon electrode (GCE) was investigated. The thiol modified probe oligonucleotides (SH-ssDNA) at the 5' phosphate end were assembled on the Au(nano)-DNA modified GCE surface. The electrochemical response of the probe immobilization and hybridiza... ( view more )tion with target DNA was measured by differential pulse voltammetry (DPV) using methylene blue (MB) as the electroactive indicator. Gold nanoparticles can be dispersed effectively on the GCE surface in the presence of calf thymus DNA. Au(nano)-DNA modified GCE could greatly increase the active sites and enhance the response signal during immobilization and hybridization. The hybridization amount of target DNA could be greatly increased. The linear detection range of Au(nano)-DNA electrode for the complementary 21-mer oligonucleotide (cDNA) was achieved from 1.52 x 10(-10) to 4.05 x 10(-8) mol L(-1). The detection limit could reach the concentration of 10(-10) mol/L. ( view less ) View Full Abstract View Article Details   Related Articles Development of a confocal optical system design for molecular imaging applications of biochip. 2007 Guoliang Huang,Shukuan Xu,Jiang Zhu,Cheng Deng,Zhonghua Dong,Yang Yang,Xiaoyong Yang,Xianhua Wang,Guofan Jin A novel confocal optical system design and a dual laser confocal scanner have been developed to meet the requirements of highly sensitive detection of biomolecules on microarray chips, which is characterized by a long working distance (wd>3.0 mm), high numerical aperture (NA=0.72), and only 3 mater... ( view more )ials and 7 lenses used. This confocal optical system has a high scanning resolution, an excellent contrast and signal-to-noise ratio, and an efficiency of collected fluorescence of more than 2-fold better than that of other commercial confocal biochip scanners. The scanner is as equally good for the molecular imaging detection of enclosed biochips as for the detection of biological samples on a slide surface covered with a cover-slip glass. Some applications of gene and protein imagings using the dual laser confocal scanner are described. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Task-modulation of functional synchrony between spontaneous low-frequency oscillations in the human brain detected by fMRI. Jul 2006 Guofan Xu,Yin Xu,Gaohong Wu,Piero G Antuono,Thomas A Hammeke,Shi-Jiang Li Recent developments in functional MRI (fMRI) technology with high spatial and temporal resolution have made it possible to noninvasively detect spontaneous low-frequency oscillations (SLOs) and quantify their functional synchrony in the human brain. In the present fMRI study the dynamic characteris... ( view more )tics of the functional synchrony between SLOs were quantitatively determined by the phase shift index (PSI). With the use of an fMRI-guided voxel-selection method, the SLOs and their functional synchrony were found to be modulated by different memory tasks. The results demonstrate that SLOs in episodic memory-related circuitry have significantly higher synchrony during the performance of declarative memory-encoding activities compared to nondeclarative memory-encoding activities. It is suggested that the dynamic property of SLOs and the quantitative assessment of their functional synchrony could be utilized as a biomarker to noninvasively characterize localized pathophysiological functions in the human brain. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Design and experimental test of diffractive superresolution elements. Jan 1, 2006 Haitao Liu,Yingbai Yan,Guofan Jin By using previously established methods based on linear programming (MLP), we design and fabricate two types of diffractive superresolution element (DSE). The structure parameters and superresolution performances of the fabricated DSEs are tested. The test results agree well with the design results... ( view more ) and are applicable to a writable or a read-only optical disk. Thus the application validity of the MLP is experimentally verified. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Design theories and performance limits of diffractive superresolution elements with the highest sidelobe suppressed. May 2005 Haitao Liu,Yingbai Yan,Guofan Jin For the application of optical data storage, theories that we present can be used to design a diffractive super-resolution element (DSE) with the highest sidelobe suppressed. A globally optimal solution among general hybrid-type filters can be solved through linear programming. The obtained globall... ( view more )y optimal performances set the exact performance limits of a general hybrid-type DSE with the highest sidelobe suppressed. A comparison of our design theories and the previous design methods shows the advantages of the former. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Compact optical roll-angle sensor with large measurement range and high sensitivity. Feb 1, 2005 Shiguang Li,Changxi Yang,Enyao Zhang,Guofan Jin A simple and effective optical roll-angle sensor based on a magnetic garnet single crystal is demonstrated. The measurement is based on the principle that, when linearly polarized light whose polarization varies alternately in two orthogonal directions passes through a polarization analyzer, the tr... ( view more )ansmitted optical intensity varies. The output voltage from an optical detector located after the analyzer can be used to determine the roll angle. The chief advantages of the sensor are that it is compact, flexible, low cost, and power effective and provides a fast response. Most importantly, the sensor is insensitive to various fluctuations such as optical intensity, photodiode responsivity, and temperature and to vibrations. This performance is most advantageous in long-distance or long-term measurements. Experimental results have shown that the angular resolution is 0.01 degree in a +/-30 degree range. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Improvement to human-face recognition in a volume holographic correlator by use of speckle modulation. Feb 1, 2005 Liangcai Cao,Qingsheng He,Chuan Ouyang,Yi Liao,Guofan Jin We show that a speckle-modulation technique can improve the parallelism and the recognition accuracy of volume holographic correlators. The object patterns are modulated by a speckle pattern generated by a diffuser. These modulated patterns are stored as Fourier holograms by use of angular-fractal ... ( view more )multiplexing. With the speckle modulation the sidelobes are completely suppressed, the cross talk is negligible, and the correlation peak becomes a bright sharp spot. Thus higher recognition accuracy is achieved. The angular separation between adjacent patterns in the multiplexing could be much smaller, resulting in larger capacity and higher parallelism of the correlator. Also, this technique can be combined with other methods such as wavelet filtering to achieve a large invariant tolerance range. Theoretical analysis, numerical evaluation, and experimental results are presented to confirm that sidelobes and cross talk are sharply suppressed by the speckle modulation. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Design and fabrication of continuous-profile diffractive micro-optical elements as a beam splitter. Oct 10, 2004 Di Feng,Yingbai Yan,Guofan Jin,Shoushan Fan An optimization algorithm that combines a rigorous electromagnetic computation model with an effective iterative method is utilized to design diffractive micro-optical elements that exhibit fast convergence and better design quality. The design example is a two-dimensional 1-to-2 beam splitter that... ( view more ) can symmetrically generate two focal lines separated by 80 microm at the observation plane with a small angle separation of +/- 16 degrees. Experimental results are presented for an element with continuous profiles fabricated into a monocrystalline silicon substrate that has a width of 160 microm and a focal length of 140 microm at a free-space wavelength of 10.6 microm. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Comparison of defocusing and fractional Fourier transform in spectroholographic storage. Sep 1, 2004 Zhuo Wang,Guofan Jin,Qingsheng He,Minxian Wu In spectroholographic storage systems the defocusing method is often used for spectrum uniformity and quality improvement of recorded information. The same purpose is served by the fractional Fourier transform (FRFT) storage system. To simplify the numerical analysis, we derive the expressions of t... ( view more )he Fraunhofer spectrum and the reconstructed image at the detected plane (CCD) for both cases instead of using the Fresnel spectrum and the FRFT spectrum. The recording aperture, spectrum uniformity, and reconstructed information of both systems are investigated. A numerical comparison is also presented. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Improved fast fractional-Fourier-transform algorithm. Sep 2004 Xingpeng Yang,Qiaofeng Tan,Xiaofeng Wei,Yong Xiang,Yingbai Yan,Guofan Jin Through the optimization of the main interval of the fractional order, an improved fast algorithm for numerical calculation of the fractional Fourier transforms is proposed. With this improved algorithm, the fractional Fourier transforms of a rectangular function and a Gaussian function are calcula... ( view more )ted. Its calculation errors are compared with those calculated with the previously published algorithm, and the results show that the calculation accuracy of the improved algorithm is much higher. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Broadband polarizing beam splitter based on the form birefringence of a subwavelength grating in the quasi-static domain. Apr 1, 2004 Deer Yi,Yingbai Yan,Haitao Liu,Si Lu,Guofan Jin We propose a novel broadband polarizing beam splitter with a compact sandwich structure that has a subwavelength grating in the quasi-static domain as the filling. The design is based on effective-medium theory an anisotropic thin-film theory, and the performance is investigated with rigorous coupl... ( view more )ed-wave theory. The design results show that the structure can provide a high polarization extinction ratio in a broad spectral range. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Transcript abundance of rml1, encoding a putative GT1-like factor in rice, is up-regulated by Magnaporthe grisea and down-regulated by light. Jan 7, 2004 Rong Wang,Guofan Hong,Bin Han We isolated and sequenced both genomic DNA and cDNA clones, which encoded a putative GT1-like protein with 385 amino acids, from cultivated rice (Oryza sativa ssp. indica). This protein shows significant amino acid sequence similarities with trihelix DNA-binding GT-1a/B2F and GT-1 factors that were... ( view more ) identified in dicot plants. Northern blotting analysis indicated that the transcript of the rice GT-1 factor in seedling was up-regulated by the rice blast fungus Magnaporthe grisea, down-regulated by various continuous light conditions and expressed rhythmically in light/dark cycles. This GT1-like factor gene was therefore designated as rml1 (rice gene regulated by M. grisea and light). The putative RML1 protein, encoded by this single copy gene, is thus identified as a new member of the plant-specific GT family of transcription factors in rice. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles [Accuracy evaluation of land vegetative cover index by RS detection] Jan 2004 Zhongxuan Zhou,Gang Wu,Guofan Shao The accuracy of GIS data is important in GIS application. In this paper, a fictitious case and an example were used to discuss the relationship between accuracy of land vegetative cover index and accuracy of image classification, and this relationship was explained by mathematics. The accuracy of l... ( view more )and vegetative cover index rested with the accuracy of image classification, but had no direct relations with total classification accuracy. User accuracy and producer accuracy had more direct control on the accuracy of land vegetative cover index than total classification accuracy; and hence, they could not be ignored in the image classification. To improve the accuracy of land vegetative cover index, user accuracy and producer accuracy of the same land type should be consistent to the greatest extent. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Analysis of power-dependent phase-matched four-wave mixing in dispersion-managed transmission systems. Dec 20, 2003 Shiming Gao,Changxi Yang,Guofan Jin We investigate power-dependent phase-matched four-wave mixing (FWM) in wavelength division multiplexing transmission lines, in which positive and negative dispersion fibers are alternately arranged to manage the dispersion and the dispersion slope. The FWM effect shows power-independent phase match... ( view more )ing when the channel power is low. However, it is power dependent at high power. The maximum FWM conversion efficiency is shifted away from the zero channel space in the case of power-dependent phase matching. Optimization of the dispersion system for suppression of the FWM effect is determined. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles [Ecological distribution of mycorrihizal fungi associated with oak in Dandong district of Liaoning Province] Dec 2003 Hui Wang,Limin Dai,Guofan Shao,Qinglong Lang,Baoshan Yang,Hongbing Deng,Qingli Wang With plot cruising and rout investigation methods, 36 species of ectomycorrhizal fungi associated with oaks were found in natural secondary oak forest in Dandong district of Liaoning Province. They were subordinated to 7 familyies, 13 genera. Studies on the relationship of the ecological distributi... ( view more )on of mycorrhizal fungi with tree species, tree age and seasons showed that 29 species mycorrhizal fugi preferred to grow with Q. mongolica, The species of Russulla were associated with a wider tree ages of oak, and the species of Amanita were most likely to grow with old tree. July and August were the occurrence peak of mycorrhizal fungi. 75% species occurred in July, and 100% species occurred in August. The relative density of the occurrence number was the highest in mid-August (19.5%) and last-August (18.4%). ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Sidelobe suppression in volume holographic optical correlators by use of speckle modulation. Oct 15, 2003 Chuan Ouyang,Liangcai Cao,Qingsheng He,Yi Liao,Minxian Wu,Guofan Jin By use of speckle modulation on the object beam of a volume holographic optical correlation system, we show that the sidelobes of the correlation patterns along the vertical direction, as well as those along the horizontal direction, are well suppressed. A theoretical explanation and experimental r... ( view more )esults are presented and discussed. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Rigorous electromagnetic design of finite-aperture diffractive optical elements by use of an iterative optimization algorithm. Sep 2003 Feng Di,Yan Yingbai,Jin Guofan,Tan Qiaofeng,Haitao Liu We propose a rigorous electromagnetic design of two-dimensional and finite-aperture diffractive optical elements (DOEs) that employs an effective iterative optimization algorithm in conjunction with a rigorous electromagnetic computational model: the finite-difference time-domain method. The iterat... ( view more )ive optimization process, the finite-difference time-domain method, and the angular spectrum propagation method are discussed in detail. Without any approximation based on the scalar theory, the algorithm can produce rigorous design results, both numerical and graphical, with fast convergence, reasonable computational cost, and good design quality. Using our iterative algorithm, we designed a diffractive cylindrical lens and a 1-to-2-beam fanner for normal-incidence TE-mode illumination, thus showing that the optimization algorithm is valid and competent for rigorously designing diffractive optical elements. Concerning the problem of fabrication, we also evaluated the performance of the DOE when the DOE profile is discrete. ( view less ) View Full Abstract View Article Details View Coded Data Related Articles Page 1 of 2 1 2 > (36 articles found)

      
 ESRNexus is provided as a service by TrialStat Corporation. ESRNexus is a registered trademark of TrialStat Corporation. Copyright 2008. View a list of all articles here