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Bioacoustic variation of swimbladder disturbance sounds in Neotropical doradoid catfishes （Siluriformes： Doradidae, Auchenipteridae）： Potential morphological correlates

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Current Zoology 2012年第1期58卷 171-188页

作者： Kaatz, Ingrid M. Stewart, Donald j. Department of Environmental and Forest Biology SUNY College of Environmental Science and Forestry Syracuse NY 13210 USA

Swimbladder disturbance sounds of doradoid catfishes （Doradidae and Aucheniptefidae） demonstrated striking waveform and spectrographic variation. We surveyed sounds of 25 doradoid species in 20 genera comparing these to sounds of four vocal outgroup catfish families. Sounds were either continuous waveforms （lacking interpulses） or pulsed （groups of pulses repeated at fixed temporal intervals）. This is the first evidence for swimbladder calls with fixed interpulse patterns in catfishes. Vocal mechanism components that were similar between doradids and auchenipterids included： swimbladder shape, swimbladder dimensions and sonic muscle-somatic index. Morphological traits that showed variation among taxa and were evaluated for po- tential correlates of call diversity are： 1） diverticula （marginal outpocketings of the swimbladder with no connection to inner ear） and 2） elastic spring apparatus Mtillerian rami （ESA-Mr）. Within the doradid subfamilies and within the Auchenipteridae most species differed significantly in dominant frequency with frequency ranges overlapping to some extent for most. Doradid swim- bladder diverticula did not explain dominant frequency variation within the doradoid superfamily. Some doradids with conical ESA-Mr had the highest dominant frequency sounds. Auchenipterids included both relatively lower and higher dominant fre- quency sound producers but lacked diverticula and had discoidal ESA-Mr. Comparing a phylogeny of doradoid genera with out- group taxa, we infer that complex diverticula and conical ESA-Mr are derived characters within the Doradidae. Species repre- senting outgroup families produced either continuous lower dominant frequency sounds （aspredinids, mochokids and pseudopimelodids） or pulsed higher dominant frequency sounds （pimelodids） [Current Zoology 58 （1）： 171-188, 2012].

关键词： Catfishes Communication Signal evolution Vocal mechanisms

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Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-Hernández A García-Murillo A Carrillo-Romo F de j Cruz-Santiago L A Chadeyron G Morales-Ramírez A de j Velumani S T.A. Post-graduate student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering Materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. Metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths

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Effect of seismic retrofit of bridges on transportation networks

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 169-179页

作者： Masanobu Shinozuka Yuko Murachi Michal j.Orlikowski Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Distinguished Professor and Chair Department of Civil and Environmental Engineering University of CaliforniaIrvineUSA Research Associate Department of Civil and Environmental Engineering Princeton UniversityUSA Undergraduate Student.

The objective of this research is to determine the effect earthquakes have on the performance of transportation network *** do this,bridge fragility curves,expressed as a function of peak ground acceleration(PGA)and peak ground velocity(PGV),were *** damage was evaluated under the 1994 Northridge earthquake and scenario earthquakes.A probabilistic model was developed to determine the effect of repair of bridge damage on the improvement of the network performance as days passed after the *** an example,the system performance degradation measured in terms of an index,'Drivers Delay,'is calculated for the Los Angeles area transportation system,and losses due to Drivers Delay with and without retrofit were estimated.

关键词： fragility curves seismic retrofit probabilistic model bridges transportation networks drivers delay performance index Northridge earthquake.

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Construction of hybrid Z-scheme graphitic C_(3)N_(4)/reduced TiO_(2) microsphere with visible-light-driven photocatalytic activity

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journal of Materiomics 2018年第3期4卷 238-246页

作者： C.Zhou N.F.Ye X.H.Yan j.j.Wang j.M.Pan D.F.Wang Q.Wang j.X.Zu X.N.Cheng School of Materials Science and Engineering Jiangsu UniversityZhenjiang212013JiangsuChina Institute for Advanced Materials Jiangsu UniversityZhenjiang212013JiangsuChina Institute of Green Materials and Metallurgy Jiangsu UniversityZhenjiang 212013JiangsuChina

A novel Z-scheme graphitic C_(3)N_(4)/reduced TiO_(2)microsphere(g-C_(3)N_(4)/r-TiO_(2))has been successfully synthesized by a solvothermal *** as-prepared samples with different contents of g-C_(3)N_(4)were characterized by X-ray diffraction,electron paramagnetic resonance,scanning electron microscope,UV *** reflectance and photoluminescence *** r-TiO_(2)microspheres are aggregated on the surface of g-C_(3)N_(4)sheets in the as-prepared g-C_(3)N_(4)/r-TiO_(2)*** g-C_(3)N_(4)/r-TiO_(2)catalysts show enhanced photocatalytic activity for the degradation of rhodamine B under visible light *** could be attributed to these influences of oxygen vacancy(changing the band gap of TiO_(2)),the large specific surface area(providing much more active sites for photocatalytic reaction),and the synergetic effect between g-C_(3)N_(4)and r-TiO_(2)(promoting the separation for photoinduced electron-hole pairs).Moreover,the Z-scheme carriers transfer mechanism in the photocatalytic process has been discussed through trapping experiments of active *** work demonstrates the strategies of the construction of Z-scheme carriers transfer system,the introduction of oxygen vacancy and structure designing are beneficial to design materials toward solar energy conversion like contaminant degradation.

关键词： TiO_(2) C_(3)N_(4) Oxygen vacancy Z-scheme heterojunction Photocatalytic performance

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STRUCTURE AND COMPOSITION OF A WATERSHED-SCALE SEDIMENT INFORMATION NETWORK

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International journal of Sediment Research 2007年第3期22卷 238-246页

作者： W. R. OSTERKAMP j. R. GRAY j. B. LARONNE j. R. MARTIN Research Hydrologist National Research Program U. S. Geological Survey Tucson AZ USA 85745 Hydrologist Office of Surface Water U. S. Geological Survey Reston VA USA 20192 Prof. Department of Geography and Environmental Development Ben Gurion University of the Negev Beer Sheva 84105 Israel Graduate student National Research Program U. S. Geological Survey Tucson AZ USA 85745

A "Watershed-Scale Sediment Information Network" (WaSSIN), designed to complement UNESCO’s International Sedimentation Initiative, was endorsed as an initial project by the World Association for Sedimentation and Erosion Research. WaSSIN is to address global fluvial-sediment information needs through a network approach based on consistent protocols for the collection, analysis, and storage of fluvial-sediment and ancillary information at smaller spatial scales than those of the International Sedimentation Initiative. As a second step of implementation, it is proposed herein that the WaSSIN have a general structure of two components, (1) monitoring and data acquisition and (2) research. Monitoring is to be conducted in small watersheds, each of which has an established database for discharge of water and suspended sediment and possibly for bed load, bed material, and bed topography. Ideally, documented protocols have been used for collecting, analyzing, storing, and sharing the derivative data. The research component is to continue the collection and interpretation of data, to compare those data among candidate watersheds, and to determine gradients of fluxes and processes among the selected watersheds. To define gradients and evaluate processes, the initial watersheds will have several common attributes. Watersheds of the first group will be: (1) six to ten in number, (2) less than 1000 km2 in area, (3) generally in mid-latitudes of continents, and (4) of semiarid climate. Potential candidate watersheds presently include the Weany Creek Basin, northeastern Australia, the Zhi Fanggou catchment, northern China, the Eshtemoa Watershed, southern Israel, the Metsemotlhaba River Basin, Botswana, the Aiuaba Experimental Basin, Brazil, and the Walnut Gulch Experimental Watershed, southwestern United States.

关键词： Sediment information Monitoring system International sediment initiative WaSSIN

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Improving QoS Using Mobility-Based Optimized Multipath Routing Protocol in MANET

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Computer Systems Science & Engineering 2023年第7期46卷 1169-1181页

作者： S.j.Sangeetha T.Rajendran Department of Computer Science Periyar UniversitySalem636011India PG and Research Department of Computer Science Government Arts and Science CollegeKangeyam638108India

Mobile Ad-hoc Networks(MANETs)connect numerous nodes to communicate data from the sender node to the target *** to the lack of an infrastructure network,mobile nodes communicate through wireless without an access *** does not have a centralized controller and has a dynamic network topology,which increases link failure and energy consumption resulting in excessive path delay,loss of Quality of service(QoS),and reduced throughput during data *** is a significant problem when the QoS of the link carrying the data is *** is one of the vital challenges of MANET due to the very dynamic and distributed nature of *** article introduces a Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)and an Efficient Reliable Link-State Transmission(ERLST)algorithm to overcome these *** proposed Mobility-Based Optimized Multipath Routing Protocol(MBOMRP)is utilized for route discovery and maintenance to efficiently avoid traffic and sleeping *** algorithm is used for efficient data transmission to increase QoS measurement parameters like throughput,Packet Delivery Ratio(PDR),and minimize the latency *** proposed MBOMRP-ERLST algorithm improves data communication network lifetime,avoids link failures,and provides efficient results compared with previous algorithms.

关键词： MANET QoS link failure improve data communication avoid traffic network lifetime MBOMRP-ERLST

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Purification of L-asparaginase II by crystallization

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Frontiers of Chemical Science and Engineering 2013年第1期7卷 37-42页

作者： Y. LIU M. PIETZSCH j. ULRICH Thermal Process Engineering Center for Engineering Science Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany Department of Downstream Processing Institute of Pharmacy Faculty of Natural Sciences I Martin Luther University Halle-Wittenberg D-06099 Halle (Saale) Germany

Here a case study ofL-asparaginase II out of a recombinant Escherichia coli is presented. The target protein was obtained by simple cell disintegration and acetone precipitation. The L-asparaginase II has been crystallized in three different forms in the following microbatch crystallization. The rod-shaped crystals （-400 μm edge length） were obtained at either 8℃ or 22℃ after 17h by addition of PEG6ooo. The rectangular-shaped crystals were obtained after further recrystallization of the rod-shaped crystals. The rhombic-shaped crystals formed at 8℃ after 12 days when cold ethanol was used instead of PEG6000. All crystallizations were performed in tris-acetate buffer （50mmol-L-1, pH 5.1）. By crystallization, the specific activity of L-asparaginase II has increased 5-fold. The protein content and the purity of the crystals were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE）. The more concentrated L- asparaginase II out of an extract mixture and the presence of only less minor proteins after crystallization demonstrates that crystallization is an effective and mild method to purify the target protein. The single crystal X-ray diffraction pattern reveals that the crystals are proteins and the X-ray powder diffraction （XRPD） pattern shows clearly that the crystals forming in PEG600o and ethanol have different crystal structures.

关键词： protein crystallization L-asparaginase II purification

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Hybrid TiO_(2)/Ag NPs/g-C_(3)N_(4) nanocomposite coatings on TC4 titanium alloy for enhanced synergistic antibacterial effect under full spectrum light

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journal of Materials Science & Technology 2022年第23期118卷 35-43页

作者： Xi.Rao L.Du j.j.Zhao X.D.Tan Y.X.Fang L.Q.Xu Y.P.Zhang School of Materials and Energy Southwest UniversityChongqing 400715China Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function Manufacturing Southwest UniversityChongqing 400715China

The hybrid TiO_(2)/AgNPs/g-C_(3) N_(4) nanocomposite coatings were constructed on TC4 alloy by a hydrothermal and calcining ***_(2)/AgNPs/g-C_(3) N_(4) nanocomposite coatings demonstrated excellent biocompatibility and osteogenesis compared to those of titanium *** existence of trace AgNPs on the surface and interface of the heterojunction could further enhance the transfer and separation of photogenerated electron/hole pairs,which greatly improved the antibacterial performance under full spectrum *** at the valence band of TiO_(2) and g-C_(3) N_(4) reacted with adsorbed H_(2) O to generate·OH,killing bacteria through photocatalytic redox reaction under light irradiation,while released AgNPs exhibited bacteriostatic efficacy with or without *** study provides a pathway of coating modification for further improving the antibacterial properties of heterojunction coatings and maintaining the biocompatibility of matrix materials.

关键词： TiO_(2)/AgNPs/g-C_(3)N_(4)nanocomposite g-C_(3)N_(4) Photocatalysis Photocatalytic inactivation of bacteria Disinfection mechanism

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Managing student Protest in Republican China： Yenching and St. john＇s Compared

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Frontiers of History in China 2013年第1期8卷 3-31页

作者： Elizabeth j. Perry Department of Government Harvard University Cambridge MA 02138 USA

Although similar in many respects, the two major Christian universities in Republican China adopted markedly different approaches to the common challenge of student nationalism. Case studies of the May Thirtieth Movement at St. john＇s University and the December Ninth Movement at Yenching University illustrate the consequences of these sharply contrasting experiences. Whereas St. john＇s was crippled by May Thirtieth, Yenching escaped December Ninth relatively unscathed. The explanation for the contrast, this paper suggests, lies not in any fundamental disagreement in the mission of the two universities or the philosophies of their famous and forceful presidents. It must be sought instead in the different campus cultures in which the student protests originated, and in the urban micro-environments in which the two universities were located： treaty-port Shanghai and post-imperial Peking.

关键词： student protest nationalism Christian universities higher education

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Risk factors for Barrett’s oesophagus and oesophageal adenocarcinoma:Results from the FINBAR study

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World journal of Gastroenterology 2007年第10期13卷 1585-1594页

作者： Lesley A Anderson RG Peter Watson Seamus j Murphy Brian T johnston Harry Comber jim Mc Guigan john V Reynolds Liam j Murray Centre for Clinical and Population Sciences Queen's UniversityBelfastNorthern Ireland Royal Group of Hospitals BelfastNorthern Ireland National Cancer Registry CorkIreland St.james's Hospital DublinIreland

AIM:To investigate risk factors associated with Barrett's oesophagus and oesophageal ***:This all-Ireland population-based case-control study recruited 224 Barrett's oesophagus patients,227 oesophageal adenocarcinoma patients and 260 *** participants underwent a structured interview with information obtained about potential lifestyle and environmental risk ***:Gastro-oesophageal reflux was associated with Barrett's [OR 12.0(95% CI 7.64-18.7)] and oesophageal adenocarcinoma [OR 3.48(95% CI 2.25-5.41)].Oesophageal adenocarcinoma patients were more likely than controls to be ex-or current smokers [OR 1.72(95% CI 1.06-2.81)and OR 4.84(95% CI 2.72-8.61)respectively] and to have a high body mass index [OR 2.69(95% CI 1.62-4.46)].No significant associations were observed between these risk factors and Barrett's *** but not vegetables were negatively associated with oesophageal adenocarcinoma [OR 0.50(95% CI 0.30-0.86)].CONCLUSION:A high body mass index,a diet low in fruit and cigarette smoking may be involved in the progression from Barrett's oesophagus to oesophageal adenocarcinoma.

关键词： Barrett's oesophagus Oesophagealadenocarcinoma Smoking Gastro-oesophageal reflux Body mass index Diet Case-control

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