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Photonic crystal ring resonator based add-drop filter using hexagonal rods for CWdM systems

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Optoelectronics Letters 2011年第3期7卷 164-166页

作者： Robinson s Nakkeeran R department of Electronics and Communication Engineering Pondicherry Engineering College

In this paper,theoretical analysis of two-dimensional photonic crystal ring resonator(2d PCRR) based add-drop filter(AdF) is presented for coarse wavelength division multiplexing(CWdM) system to drop a channel at 1511 nm using hexagonal rods that are positioned in the square *** 2d finite difference time domain(2d FdTd) method and plane wave expansion(PWE) method are used for obtaining the filter response and band structure of the filter *** to 100 dropping and coupling efficiencies at 1511 nm and 16 nm of bandwidth are observed through *** is very well meeting the requirement of ITU-T G.694.2 standard,which is specified for metro access and short haul optical *** overall size of the proposed filter is 11.4 μm×11.4 μ*** can also be used in integrated optics.

关键词：二维光子晶体 WdM系统滤波器谐振环纳米通道时域有限差分粗波分复用平面波展开

Neurodevelopment and degeneration

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Neuroscience Bulletin 2014年第4期30卷 539-541页

作者： Margaret s.Ho department of Anatomy and Neurobiology School of MedicineTongji University

Over the past decades, continuous effort has been made to resolve unsettled matters in the emerging scene of neuronal development. despite the rapid progress, neuroscientists remain fascinated by the intricate networks of signaling pathways and molecules conserved among species. Fundamental questions such as progenitor cell specification, compartmentalized cellular tactics, and the identification of factors involved in orchestrating the progression of development are being actively pursued. Furthermore, reversing the effects of development, neurodegeneration symbolizes an opposite force in limiting growth and has been linked to a variety of diseases. To date, a tremendous amount of work from the research community has conceptualized the central image of how nervous systems develop and are equipped to modulate animal functions, albeit with mysterious gaps in the picture that remain to be filled.

关键词： Neurodevelopment degeneration equipped

soil Microbial Activities in Beech Forests Under Natural Incubation Conditions as Affected by Global Warming

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Pedosphere 2014年第6期24卷 709-721页

作者： s.LU Q.WANG s.KATAHATA M.NARAMOTO H.MIZUNAGA Graduate school of science and Technology Shizuoka University Graduate school of Agriculture Shizuoka University

Microbial activity in soil is known to be controlled by various factors. However, the operating mechanisms have not yet been clearly identified, particularly under climate change conditions, although they are crucial for understanding carbon dynamics in terrestrial ecosystems. In this study, a natural incubation experiment was carried out using intact soil cores transferred from high altitude(1 500 m) to low(900 m) altitude to mimic climate change scenarios in a typical cold-temperate mountainous area in Japan. soil microbial activities, indicated by substrate-induced respiration(sIR) and metabolic quotient(q CO2), together with soil physicalchemical properties(abiotic factors) and soil functional enzyme and microbial properties(biotic factors), were investigated throughout the growing season in 2013. Results of principal component analysis(PCA) indicated that soil microbial biomass carbon(MBC) andβ-glucosidase activity were the most important factors characterizing the responses of soil microbes to global warming. Although there was a statistical difference of 2.82 ℃ between the two altitudes, such variations in soil physical-chemical properties did not show any remarkable effect on soil microbial activities, suggesting that they might indirectly impact carbon dynamics through biotic factors such as soil functional enzymes. It was also found that the biotic factors mainly controlled soil microbial activities at elevated temperature,which might trigger the inner soil dynamics to respond to the changing environment. Future studies should hence take more biotic variables into account for accurately projecting the responses of soil metabolic activities to climate change.

关键词： biotic factors carbon dynamics metabolic quotient microbial biomass soil enzymes soil respiration

Effects of atmospheric gases on terrestrial plants and critical levels of air pollution

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Journal of Environmental sciences 1992年第1期4卷 10-14页

作者： s.M.semenov Natural Environment and Climate Monitoring Laboratory Moscow 107258 Glebovskaya 20b LAM

An integrated approach was developed to determine the critical levels of air pollution for ecological standard setting based on the unified index of biological response, by taking into account the effects of all pollution components simultaneously. An empirical model of plant productivity was taken as the dose response model for gaseous pollutant effect on the productivity of trees and the annual productivity of plants was used as the above mentioned index. The CO2 increase in the lower atmosphere was considered to potentially increase plant productivity and NO2 was estimated as neutral while being dangerous for plants as a chemical precursor of ozone or as a source of acidification. The maximum permissible chronic O3 and sO2 levels for trees were estimated and it was found that O3 is much more phytotoxic, as compared to sO2 , with a rather narrow range of permissible levels (27-33 ppb) which complicates its monitoring and control.

关键词： air pollution biological responses terrestrial plants.

Arsenic removal from water by iron-sulphide minerals

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Chinese science Bulletin 2000年第15期45卷 1430-1434页

作者： William s.Fyfe department of Earth sciences the University of Western OntarioLondonOntario N6A 5B7Canada

n bench-scaled experiments, iron-sulphide minerals, pyrite and pyrrhotite are used as adsorbents for arsenic removal from As-spiked water of As5+ and As3+ species. The adsorption rate, efficiency, As-adsorption stability and the associated pH conditions have been examined. Observations indicate that these iron-sulphide minerals are very efficient to adsorb arsenic from water for both As5+ and As3+ species. similar to other studies, As3+-adsorption shows a slower rate than As3+. The stability of the adsorbed arsenic seems closely related to the pH values of the solution. A lower pH level commonly less than 4.0 is required to protect the adsorbed arsenic from serious oxidation and backward release. Fining of the mineral powders and shaking of the solution during adsorption enhance the adsorption efficiency and adsorption rate. For practical use of the method presented in this study, the waste produced should be managed with great care to keep it from redistribution over water system. A further study of

关键词： arsenic contamination arsenic removal iron-sulphide minerals.

Towards frequency adaptation for delayed feedback deep brain stimulations

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Neural Regeneration Research 2018年第3期13卷 408-409页

作者： Mohammad daneshzand Miad Faezipour Buket d.Barkana d-BEsT Lab Departments of Computer Science and Engineering and Biomedical Engineering University of Bridgeport department of Electrical Engineering University of Bridgeport

In neurodegenerative disorders such as Parkinson＇s disease （Pd）, deep brain stimulation （dBs） is a desirable approach when the medication is less effective for treating the symptoms. dBs incorporates transferring electrical pulses to a specific tissue of the central nervous system, obtaining therapeutic results by modulating the neuronal activity of that region. dBs has certain advantages such as reversibility and adjustability features over medication, since the neuronal firing patterns can be recorded and used to alter the parameters of the dBs signal （Benabid et al., 2009）. One of the dBs indications is its ability to suppress the abnormal neuronal activity to treat symptoms like tremor, akinesia and dystonia.

关键词： Figure dBs Towards frequency adaptation for delayed feedback deep brain stimulations sTN HFs

Protein-protein complexation in bioluminescence

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Protein & Cell 2011年第12期2卷 957-972页

作者： Maxim s.Titushin Yingang Feng John Lee Eugene s.Vysotski Zhi-Jie Liu National Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China Qingdao Institute of Bioenergy and Bioprocess Technology Chinese Academy of SciencesQingdao 266101China department of Biochemistry and Molecular Biology University of GeorgiaAthensGA 30602USA Laboratory of Photobiology Institute of Biophysics Russian Academy of SciencesSiberian BranchKrasnoyarsk 660036Russia

In this review we summarize the progress made towards understanding the role of protein-protein interactions in the function of various bioluminescence systems of marine organisms,including bacteria,jellyfish and soft corals,with particular focus on methodology used to detect and characterize these *** some bioluminescence systems,protein-protein interactions involve an“accessory protein”whereby a stored substrate is efficiently delivered to the bioluminescent enzyme *** types of complexation mediate energy transfer to an“antenna protein”altering the color and quantum yield of a bioluminescence *** structures of the complexes reveal an important role of electrostatic forces in governing the corresponding weak interactions and define the nature of the interaction *** most reliable structural model is available for the protein-protein complex of the Ca2+-regulated photoprotein clytin and green-fluorescent protein(GFP)from the jellyfish Clytia gregaria,solved by means of Xray crystallography,NMR mapping and molecular *** provides an example of the potential strategies in studying the transient complexes involved in *** is emphasized that structural studies such as these can provide valuable insight into the detailed mechanism of bioluminescence.

关键词： green-fluorescent protein(GFP) photoprotein luciferase lumazine protein Förster resonance energy transfer(FRET) docking

Transrectal ultrasound and magnetic resonance imaging measurement of extramural tumor spread in rectal cancer

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World Journal of Gastroenterology 2012年第36期18卷 5021-5026页

作者： sφren R Rafaelsen Chris Vagn-Hansen Torben sφrensen John Plφen Anders Jakobsen department of Radiology DCCG SouthInstitute of Regional Health Services ResearchUniversity of Southern DenmarkVejle HospitalKabbeltoft 257100 VejleDenmark department of Oncology DCCG SouthInstitute of Regional Health Services ResearchUniversity of Southern DenmarkVejle HospitalKabbeltoft 257100 VejleDenmark

AIM： To evaluate the agreement between transrectal ultrasound （TRUs） and magnetic resonance imaging （MRI） in classification of ≥ T3 rectal tumors. METHOds： From January 2010 to January 2012, 86 consecutive patients with ≥ T3 tumors were included in this study. The mean age of the patients was 66.4 years （range： 26-91 years）. The tumors were all ≥ T3 on TRUs. The sub-classification was defined by the penetration of the rectal wall： a： 0 to 1 mm; b： 1-5 mm, c： 6-15; d：〉 15 mm. Early tumors as ab （≤ 5 ram） and advanced tumors as cd （〉 5 mm）. All patients underwent TRUs using a 6.5 MHz transrectal transducer. The MRI was performed with a 1.5 T Phil- ips unit. The TRUs findings were blinded to the radiol- ogist performing the interpretation of the MRI images and measuring the depth of extramural tumor spread REsULTs： TRUs found 51 patients to have an early ≥ T3 tumors and 35 to have an advanced tumor, where- as MRI categorized 48 as early ≥ T3 tumors and 38 as advanced tumors. No patients with tumors classified as advanced by TRUs were found to be early on MRI. The kappa value in classifying early versus advanced T3 rectal tumors was 0.93 （95% CI： 0.85-1.00）. We found a kappa value of 0.74 （95% CI： 0.63-0.86） for the total sub-classification between the two methods. The mean maximal tumor outgrowth measured by TRUs, 5.5 mm ± 5.63 mm and on MRI, 6.3 mm ±6.18 mm, P = 0.004. In 19 of the 86 patients the following CT scan or surgery revealed distant metastases; of the 51 patients in the ultrasound ab group three （5.9%） had metastases, whereas 16 （45.7%） of 35 in the cd group harbored distant metastases, P = 0.00002. The odds ratio of having distant metastases in the ultra- sound cd group compared to the ab group was 13.5 （95% CI： 3.5-51.6）, P = 0.00002. The mean maximal ultrasound measured outgrowth was 4.3 mm （95% CI： 3.2-5.5 mm） in patients without distant metastases, while the mean maximal outgrowth was 9.5 mm （95% CI： 6.2-12.8 ram） in the patients with metastases, P = 0

关键词： Ultrasound Magnetic resonance imaging Rectal cancer Tumor staging Metastases

Phenotypic differences between coryneform bacteria isolated from seminal fluid of healthy men and men with chronic prostatitis syndrome

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Asian Journal of Andrology 2009年第4期11卷 517-520页

作者： Iuri B Ivanov Viktor A Gritsenko Michael d Kuzmin department of Human Microbiology Institute of Cellular and Intracellular Symbiosis Russian Academy of Sciences Orenburg 460056 Russia

We compared the potential phenotypic properties of coryneform bacteria associated with chronic prostatitis syndrome （CPs）, such as secretory inhibitor of lysozyme （sIL） and secretory inhibitor of platelet microbicidal protein （sIPMP）. A total of 110 clinical isolates of coryneform bacteria isolated from the seminal fluid of healthy men and men with CPs were tested. sIPMP production was tested by inhibiting platelet microbicidal protein （PMP） bioactivity against Bacillus subtilis, and was expressed as percentage of inhibition of PMP bactericidal activity. sIL production was tested by inhibiting lysozyme activity against Micrococcus lysodeikticus and was expressed in microgram per millilitre of inactivated lysozyme. A significantly higher proportion of CPs strains （58.7% vs. 19.2 %） was sIPMP-positive compared with non-CPs strains （P 〈 0.01）. Of the CPs strains tested, 77.8% were sIL-positive compared with 34% of the non- CPs isolates （P 〈 0.05）. These results suggest that the diagnosis of CPs should not rely solely on classical parameters, for example, the identification and counting of microorganisms, but the functional significance of these parameters must be estimated, possibly by the concentration of different bacterial substrains, detection of opportunistic microorganisms with pathogenic properties, such as pronounced resistance to the cationic antimicrobial peptides, and/or the ability to inhibit the antimicrobial host defence factors.

关键词： Corynebacterium spp lysozyme platelet microbicidal protein prostatitis