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The photometric system of the One-meter Telescope at Weihai Observatory of Shandong University 被引量:6
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作者 Shao-Ming Hu Sheng-Hao Han +1 位作者 Di-Fu Guo Jun-Ju Du 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第6期719-732,共14页
The one-meter telescope at Weihai Observatory (WHO) of Shandong University is an f/8 Cassegrain telescope. Three sets of filters are installed in a dual layer filterwheel that use Johnson-Cousins UBVRI, Sloan Digita... The one-meter telescope at Weihai Observatory (WHO) of Shandong University is an f/8 Cassegrain telescope. Three sets of filters are installed in a dual layer filterwheel that use Johnson-Cousins UBVRI, Sloan Digital Sky Survey u′g′r′i′z′ and Stomgren uvby. The photometric system and the CCD camera are introduced, followed by detailed analysis of their performances, and determination of the relevant parameters, including gain, readout noise, dark current and linearity of the CCD cam- era. In addition, the parameters describing the site's astro-climate, including typical seeing, statistics on the number of clear nights and average sky brightness, based on data gathered from Sep. 2007 to Aug. 2013, are systematically studied and reported in this work. Photometric calibrations were done using Landolt standard star obser- vations spanning eight nights, which yielded transformation coefficients, photometric precision and system throughput. The limiting magnitudes are simulated using the derived calibration parameters and classic observation conditions at WHO. 展开更多
关键词 telescopes -- site testing --instrumentation: miscellaneous - tech-niques photometric
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Design and calibration of a high-sensitivity and high-accuracy polarimeter based on liquid crystal variable retarders 被引量:1
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作者 Jing Guo De-Qing Ren +4 位作者 Cheng-Chao Liu Yong-Tian Zhu Jiang-Pei Dou Xi Zhang Christian Beck 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第1期87-96,共10页
Polarimetry plays an important role in the measurement of solar magnetic fields. We devel- oped a high-sensitivity and high-accuracy polarimeter (HHP) based on nematic liquid crystal variable retarders (LCVRs), wh... Polarimetry plays an important role in the measurement of solar magnetic fields. We devel- oped a high-sensitivity and high-accuracy polarimeter (HHP) based on nematic liquid crystal variable retarders (LCVRs), which has a compact setup and no mechanical moving parts. The system design and calibration methods are discussed in detail. The azimuth error of the transmission axis of the polarizer as well as the fast axes of the two LCVRs and the quarter-wave plate were determined using dedicated procedures. Linearly and circularly polarized light were employed to evaluate the performance of the HHP. The experimental results indicate that a polarimetric sensitivity of better than 5.7 × 10-3 can be achieved by using a single short-exposure image, while an accuracy on the order of 10-5 can be reached by using a large number of short-exposure images. This makes the HHP a high-performance system that can be used with a ground-based solar telescope for high-precision solar magnetic field investigations. 展开更多
关键词 instrumentation polarimeters - methods laboratory - Sun magnetic fields - tech-niques polarimetric
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Clinical Criteria for Airway Assessment: Correlations with Laryngoscopy and Endotracheal Intubation Conditions
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作者 Gustavo Henrique S. Wanderley Luciana Cavalcanti Lima +4 位作者 Tania Cursino de Menezes Couceiro Waston Vieira Silva Raquel Queiroz G. A. Coelho Andrea Cavalcanti C. Lucena Anne Danielle Santos Soares 《Open Journal of Anesthesiology》 2013年第7期320-325,共6页
Difficult intubation, inadequate ventilation and esophageal intubation are the principal causes of death or brain damage related to airway manipulation. The objective of this cross-sectional study was to correlate a p... Difficult intubation, inadequate ventilation and esophageal intubation are the principal causes of death or brain damage related to airway manipulation. The objective of this cross-sectional study was to correlate a preanesthetic evaluation that may be capable of predicting a difficult intubation with the conditions encountered at laryngoscopy and endotracheal intubation. Eighty-one patients submitted to general anesthesia were evaluated at a preanesthetic consultation according to the modified Mallampati classification, the Wilson score and the American Society of Anesthesiologists (ASA) difficult airway algorithm. Findings were then correlated with the Cormack-Lehane classification and with the number of attempts at endotracheal intubation. No statistically significant correlations were found between the patients’ Mallampati classification and their Cormack-Lehane grade or between the Mallampati classification and the number of attempts required to achieve endotracheal intubation. Laryngoscopy proved difficult in four patients and in all of these cases the Wilson score had been indicative of a possibly difficult airway, highlighting its good predicting sensitivity. However, the specificity of this test was low, since another 24 patients had the same Wilson score but were classified as Cormack-Lehane I/II. Moreover, two patients who had a Wilson score ≥ 4 were also classified as Cormack-Lehane grade I/II. The study concluded that the Wilson score, although seldom used in clinical practice, is a highly sensitive predictor of a difficult airway;its specificity, however, is low. 展开更多
关键词 Preanesthetic Evaluation Respiratory System AIRWAY ENDOTRACHEAL INTUBATION Measurement tech-niques Mallampati WILSON Cormack-Lehane
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Near-infrared observations of the Be/X-ray binary pulsar A0535+262
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作者 Sachindra Naik Blesson Mathew +2 位作者 D.P.K.Banerjee N.M.Ashok Rajeev R.Jaiswal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第2期177-186,共10页
We present the results obtained from extensive near-infrared (IR) spectro- scopic and photometric observations of the Be/X-ray binary A0535+262/HDE 245770 at different phases of its - 111 d orbital period. This obs... We present the results obtained from extensive near-infrared (IR) spectro- scopic and photometric observations of the Be/X-ray binary A0535+262/HDE 245770 at different phases of its - 111 d orbital period. This observation campaign is part of the monitoring program of selective Be/X-ray binary systems aimed at understanding X-ray and near-IR properties at different orbital phases, especially during the perias- tron passage of the neutron star. The near-IR observations presented here were carried out using the 1.2 m telescope at the Mt. Abu IR Observatory. Though the source was relatively faint for spectroscopic observations with the 1.2 m telescope, we monitored the source closely during the 2011 February-March giant X-ray outburst to primarily investigate whether any drastic changes in the near-IR JHK spectra took place at the periastron passage. Changes of such a striking nature were expected to be detectable in our spectra. Photometric observations of the Be star show a gradual and systematic fading in the JHK light curves since the onset of the X-ray outburst, which could suggest a mild evacuation/truncation of the circumstellar disk of the Be companion. Near-IR spectroscopy of the object shows that the JHK spectra are dominated by the emission lines of hydrogen Brackett and Paschen series and HeI lines at 1.0830, 1.7002 and 2.0585 μm. The presence of all the hydrogen emission lines in the JHK spectra, along with the absence of any significant change in the continuum of the Be companion during X-ray quiescent and X-ray outburst phases, suggests that the near- IR line emitting regions of the disk are not significantly affected during the X-ray outburst. 展开更多
关键词 infrared: stars - Be binaries - stars: individual (A0535+262) - tech-niques spectroscopic
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Regulatory effects of anandamide on intracellular Ca^(2+) concentration increase in trigeminal ganglion neurons
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作者 Yi Zhang Hong Xie +6 位作者 Gang Lei Fen Li Jianping Pan Changjin Liu Zhiguo Liu Lieju Liu Xuehong Cao 《Neural Regeneration Research》 SCIE CAS CSCD 2014年第8期878-887,共10页
Activation of cannabinoid receptor type 1 on presynaptic neurons is postulated to suppress neu- ~ ~ ~ 2+ ~ ~ 2+ rotransmlsslon by decreasing Ca reflux through high voltage-gated Ca channels. However, recent studies... Activation of cannabinoid receptor type 1 on presynaptic neurons is postulated to suppress neu- ~ ~ ~ 2+ ~ ~ 2+ rotransmlsslon by decreasing Ca reflux through high voltage-gated Ca channels. However, recent studies suggest that cannabinoids which activate cannabinoid receptor type 1 can increase neurotransmitter release by enhancing Ca2+ influx in vitro. The aim of the present study was to investigate the modulation of intracellular Ca2+ concentration by the cannabinoid receptor type 1 agonist anandamide, and its underlying mechanisms. Using whole cell voltage-damp and calcium imaging in cultured trigeminal ganglion neurons, we found that anandamide directly caused Ca2+ influx in a dose-dependent manner, which then triggered an increase of intracellular Ca2+ concentration. The cyclic adenosine and guanosine monophosphate-dependent protein kinase systems, but not the protein kinase C system, were involved in the increased intracellular Ca2+concentration by anandamide. This result showed that anandamide increased intracellu- lar Ca2+ concentration and inhibited high voltage-gated Ca2+ channels through different signal transduction pathways. 展开更多
关键词 nerve regeneration trigeminal ganglion NEURONS ENDOCANNABINOIDS ANANDAMIDE can-nabinoid receptor type 1 voltage-dependent calcium channels vanilloid receptor patch-damp tech-nique calcium cyclic adenosine monophosphate protein kinase protein kinase C NIH grant neuralregeneration
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Solving shock wave with discontinuity by enhanced differential transform method(EDTM)
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作者 邹丽 王振 +2 位作者 宗智 邹东阳 张朔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2012年第12期1569-1582,共14页
An enhanced differential transform method (EDTM), which introduces the Pad@ technique into the standard differential transform method (DTM), is proposed. The enhanced method is applied to the analytic treatment of... An enhanced differential transform method (EDTM), which introduces the Pad@ technique into the standard differential transform method (DTM), is proposed. The enhanced method is applied to the analytic treatment of the shock wave. It accelerates the convergence of the series solution and provides an exact Dower series solution. 展开更多
关键词 enhanced differential transform method (EDTM) shock wave Pad@ tech-nique Burgers equation
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Environmental Assessment and Dielectric Performances of the Secondary Electrical Insulation in Low Voltage Motors Impregnated by Different Techniques
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作者 Manh Quan Nguyen Simon Dario +4 位作者 David Malec Dominique Mary Jean-Pascal Cambronne Damien Prunel Julie Orgelet 《Engineering(科研)》 2017年第10期860-873,共14页
A recent technique, using to potentially replace the conventional impregnating one in low voltage electric motors, has been studied in this communication. The conventional technique that uses?both primary and secondar... A recent technique, using to potentially replace the conventional impregnating one in low voltage electric motors, has been studied in this communication. The conventional technique that uses?both primary and secondary insulations;?i.e.: enamel and varnish, has been compared to this recent technique which only uses one component,?i.e.: self-bonding wires. Self-bonding wires polymerization is very quick compared to that of the conventional technique. Environmental impact and both dielectric and mechanical properties of these two techniques have been estimated and compared. The goal is to estimate if this recent technique has not only a better environmental footprint but also good technical properties. The dielectric properties that have been measured are the dielectric strength and?the lifetime under pulse?voltage while mechanical consists in measuring the bonding strength that is crucial for impregnation.?For that purpose, a Life Cycle Assessment (LCA) that can simultaneously evaluatenumerous impacts on ground, water and air,?has been performed. The results show clearly that the recent technique significantly reduces the environmental footprint. Both mechanical and dielectric properties are then compared and analyzed. 展开更多
关键词 Electrical MOTOR Enameled WIRE Self-Bonding WIRE IMPREGNATION tech-nique Dielectric Performance Environmental Impact
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Vertical Handover Decision for Mobile IoT Edge Gateway Using Multi-Criteria and Fuzzy Logic Techniques
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作者 Amit Singh Gaur Jyoti Budakoti Chung-Horng Lung 《Advances in Internet of Things》 2020年第4期57-93,共37页
Internet of Things (IoT) is ubiquitous, including objects or devices communicating through heterogenous wireless networks. One of the major challenges in mobile IoT is an efficient vertical handover decision (VHD) tec... Internet of Things (IoT) is ubiquitous, including objects or devices communicating through heterogenous wireless networks. One of the major challenges in mobile IoT is an efficient vertical handover decision (VHD) technique between heterogenous networks for seamless connectivity with constrained resources. The conventional VHD approach is mainly based on received signal strength (RSS). The approach is inefficient for vertical handover, since it always selects the target network with the strongest signal without taking into consideration of factors such as quality of service (QoS), cost, delay, etc. In this paper, we present a hybrid approach by integrating the multi-cri- teria based VHD (MCVHD) technique and an algorithm based on fuzzy logic for efficient VHD among Wi-Fi, Radio and Satellite networks. The MCVHD provides a lightweight solution that aims to achieving seamless connectivity for mobile IoT Edge Gateway over a set of heterogeneous networks. The proposed solution is evaluated in real time using a testbed containing real IoT devices. Further, the testbed is integrated with lightweight and efficient software techniques, e.g., microservices, containers, broker, and Edge/Cloud techniques. The experimental results show that the proposed approach is suitable for an IoT environment and it outperforms the conventional RSS Quality based VHD by minimizing handover failures, unnecessary handovers, handover time and cost of service. 展开更多
关键词 Internet of Things (IoT) Handover Vertical Handover Decision (VHD) tech-nique for Order Preference by Similarity to Ideal Solution (TOPSIS) Mul-ti-Criteria Based VHD (MCVHD) Containers Microservice Edge Computing
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Contributions to data transmission at critical moments on unmanned aerial vehicles
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作者 Jose Enrique RODRIGUEZ David SEGURADO +2 位作者 Manuel SANCHEZ Jose Javier MARTINEZ Rafael GONZALEZ 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第8期247-257,共11页
As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be s... As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be sufficiently precise to obtain a good characterization of aircraft.This article proposes new methods of sending information to ground, which make it possible to know the aircraft behavior accurately, and for this purpose, four contributions have been made for ALO(Avión Ligero de Observación, Spanish acronym for Light Observation Aircraft). Currently, the characterization is based on data obtained at ten samples per second, insufficient to acquire detailed knowledge of what happened during the whole flight of an aircraft. As a result of these contributions, many more samples per second of accelerations and angular velocities are obtained at the most critical moments of the flight, such as takeoff or landing. Among the improvements included are data compression techniques, providing references to locate the measured data in time and identifying labels of each parameter. 展开更多
关键词 Critical moments Data transmission Datacompression tech-niques Radio-modem Recommended Standard 232(RS-232) Unmannedaerial vehicle
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Targeted Mitochondrial Delivery to Hepatocytes:A Review
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作者 Brent D.Heineman Xiaocong Liu George Y.Wu 《Journal of Clinical and Translational Hepatology》 SCIE 2022年第2期321-328,共8页
Defects in mitochondria are responsible for various genetic and acquired diseases.Mitochondrial transplantation,a method that involves introduction of healthy donor mitochondria into cells with dysfunctional mitochond... Defects in mitochondria are responsible for various genetic and acquired diseases.Mitochondrial transplantation,a method that involves introduction of healthy donor mitochondria into cells with dysfunctional mitochondria,could offer a novel approach to treat such diseases.Some studies have demonstrated the therapeutic benefit of mitochondrial transplantation and targeted delivery in vivo and in vitro within hepatocytes and the liver.This review discusses the issues regarding isolation and delivery of mitochondria to hepatocytes and the liver,and examines the existing literature in order to elucidate the utility and practicality of mito-chondrial transplantation in the treatment of liver disease.Studies reviewed demonstrate that mitochondrial uptake could specifically target hepatocytes,address the challenge of non-specific localization of donor mitochondria,and provide evidence of changes in liver function following injection of mitochondria into mouse and rat disease models.While potential benefits and advantages of mitochondrial trans-plantation are evident,more research is needed to determine the practicality of mitochondrial transplantation for the treatment of genetic and acquired liver diseases. 展开更多
关键词 MITOCHONDRIA HEPATOCYTES TRANSPLANTATION Liver In vitro tech-niques
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Design and application of 60mer oligonucleotide microarray in SARS coronavirus detection 被引量:4
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作者 SHI Rong MA Wenli +6 位作者 WU Qinghua ZHANG Bao SONG Yanbin GUO Qiuye XIAO Weiwei WANG Yan ZHENG Wenling 《Chinese Science Bulletin》 SCIE EI CAS 2003年第12期1165-1169,共4页
The 60mer oligonucleotide microarray was designed and applied to detecting of SARS (severe acute res-piratory syndrome) coronavirus. Thirty 60mer specific oligos were designed to cover the whole genome of the first su... The 60mer oligonucleotide microarray was designed and applied to detecting of SARS (severe acute res-piratory syndrome) coronavirus. Thirty 60mer specific oligos were designed to cover the whole genome of the first submit-ted coronavirus strain, according to the sequence of TOR2 (GENEBANK Accession: AY274119). These primers were synthesized and printed into a microarray with 12×12 spots. RNAs were extracted from the throat swab and gargling fluid of SARS patients and reverse-transcripted into the double strand cDNAs. The cDNAs were prepared as re-stricted cDNA fragments by the restriction display (RD) technique and labeled by PCR with the Cy5-universal primer. The labeled samples were then applied to the oligo microar-ray for hybridization. The diagnostic capability of the mi-croarray was evaluated after the washing and scanning steps. The scanning result showed that samples of SARS patients were hybridized with multiple SARS probes on the microar-ray, and there is no signal on the negative and blank controls. These results indicate that the genome of SARS coronavirus can be detected in parallel by the 60mer oligonucleotide mi-croarray, which can improve the positive ratio of the diagno-sis. The oligo microarray can also be used for monitoring the behavior of the virus genes in different stages of the disease status. 展开更多
关键词 SARS CORONAVIRUS OLIGONUCLEOTIDE MICROARRAY RD tech-nique fluorescent LABELING molecular hybridization.
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Using RAPD in Neisseria gonorrhoeae genotyping and transmission detection
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作者 Tiejun ZHANG Xiaoming ZHOU +3 位作者 Tao ZHANG Yue CHEN Shunzhang YU Qingwu JIANG 《Frontiers of Medicine》 SCIE CSCD 2008年第3期269-275,共7页
The aim of this paper is to develop an applic-able Random Amplified Polymorphic DNAs(RAPD)method for genotyping Neisseria gonorrhoeae strain,and discuss the possibility of using the RAPD method to trace N.gonorrhoeae ... The aim of this paper is to develop an applic-able Random Amplified Polymorphic DNAs(RAPD)method for genotyping Neisseria gonorrhoeae strain,and discuss the possibility of using the RAPD method to trace N.gonorrhoeae strain transmission route.Four different pretreatment methods were used on the N.gonorrhoeae genomic DNA component,and the best adaptive extract method was selected for RAPD.Different RAPD primers sequence was used for amplification and their differenti-ating capabilities for N.gonorrhoeae strains were com-pared.Applicable RAPD primer was selected for N.gonorrhoeae genotyping and then applied into transmis-sion detection.The results show that the so called cetyl-trimethylammonium bromide(CTAB)method for extracting genomic DNA could give integrated genomic DNA and give out relatively better RAPD fingerprint maps,subsequently,using selected RAPD primer could give out a group of amplification polymerase chain reac-tion bands.The fingerprint maps from different N.gonor-rhoeae strains were distinctive.Some main segments were common to all the N.gonorrhoeae strains tested.Some segments were different among the N.gonorrhoeae strains.According to the fingerprint maps and similarity index of different N.gonorrhoeae isolates,isolates from a pair of sex-partners were very similar.Based on these findings,the best extracting method and suitable RAPD primer were chosen.The RAPD fingerprint maps could type N.gonorrhoeae effectively and could be used as an additional approach in molecular epidemiology for tracing infection sources. 展开更多
关键词 random amplified polymorphic DNA tech-nique Neisseria gonorrhoeae GENOTYPE epidemiology molecular
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