• Title/Summary/Keyword: selective availability

Search Result 55, Processing Time 0.027 seconds

A comparative review of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia: exploring the factors behind epinephrine's prevalence in the US

  • Navkiran Deol;Gerardo Alvarez;Omar Elrabi;Gavin Chen;Nalton Ferraro
    • Journal of Dental Anesthesia and Pain Medicine
    • /
    • v.23 no.6
    • /
    • pp.293-302
    • /
    • 2023
  • This review paper delves into the comparative study of epinephrine and phenylephrine as vasoconstrictors in dental anesthesia, exploring their histories, pharmacological properties, and clinical applications. The study involved a comprehensive literature search, focusing on articles that directly compared the two agents in terms of efficacy, safety, and prevalence in dental anesthesia. Epinephrine, with its broad receptor profile, has been a predominant choice, slightly outperforming in the context of prolonging dental anesthesia and providing superior hemostasis, which is crucial for various dental procedures. However, the stimulation of beta-adrenergic receptors caused by epinephrine poses risks, especially to patients with cardiovascular conditions. Phenylephrine, a selective alpha-1 adrenergic agonist, emerges as a safer alternative for such patients, avoiding the cardiovascular risks associated with epinephrine. Moreover, its vasoconstrictive effect may not be as deleterious as that of epinephrine, due to its selective action. This review reveals that despite the potential benefits of phenylephrine, epinephrine continues to dominate in clinical settings, due to its historical familiarity, availability, and cost-effectiveness. The lack of commercially available pre-made phenylephrine dental carpules in most countries, except Brazil, and a knowledge gap within dental academia regarding phenylephrine, contribute to its limited use. This review concludes that while both agents are effective, the choice between them should be based on individual patient conditions, availability, and the practitioner's knowledge and familiarity with the agents. The underuse of other vasoconstrictors like levonordefrin and the unavailability of phenylephrine in pre-mixed dental cartridges in many countries highlights the need for further exploration and research in this field. Furthermore, we also delve into the role of levonordefrin and examine the rationale behind the exclusion of phenylephrine from commercially available pre-mixed local anesthetic carpules, suggesting a need for a responsive approach from pharmaceutical manufacturers to the distinct needs of the dental community.

Development of the hybrid algorithm for the car navigation system (자동차 항법용 혼합항법 알고리즘 개발)

  • 김상겸;양승규;김정하
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1997.10a
    • /
    • pp.1403-1406
    • /
    • 1997
  • Generally, G.P.S(Global Positioning System) is using for the car navigation system but it has some restrictions such as the discontinuity of earth satellites and SA (Selective Availability). Recently, the hybrid navigation system combining with G.P.S and Dead-reckoning are much attractuve for improving the accuracy of a vehicle positioning. G.P.S called satellite navigation system, can measure its position by using satellites. Dead-Reckoning is the self-contained navigatioin system using a wheel sensor for the vehicle velocity and a gyro sensor for the vehicle angular velocity. Some algorithm could be generated for finding the vehicle position and orientation. In this paper, we developed a hybrid algotithm wiht G.P.S DR and Map-Matching.

  • PDF

Correlator Design for L1/L2C GPS Signal

  • Chang, Jae-Won;Kim, Keun-Taek;Lee, Sang-Jeong
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.2623-2626
    • /
    • 2003
  • GPS provides two services which include SPS(Standard Positioning Service) and PPS(Precise Positioning Service). While SPS users can navigate in more precise due to cancellation of SA(Selective Availability), SPS users has still less precision navigation than PPS users. L1/L2CS integrated receiver can provide more precise navigation to SPS users because the delay of Ionosphere will be cancelled by using two frequencies (L1 and L2). This paper designs an integrated L1/L2CS digital correlator to prepare the L2C signal that will be provided in 2003. Also L2CS transmitter is designed to confirm L2CS correlator.

  • PDF

Performance Enhancement of GNSS Positioning using European Galileo System (유럽의 Galileo 시스템을 이용한 GNSS 측위 성능 향상)

  • Bae Kyoung-Ho;Heo Min;Lee Yong-Wook;Lee Jae-One
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2006.04a
    • /
    • pp.33-37
    • /
    • 2006
  • After USA removed the Selective Availability(SA), Global Positioning System(GPS) has monopolized tile world market and other countries have been depended on GPS, absolutely So the other countries, Russia, European Community(EC) and Japan, which apprehend to monopolize in technical and strategic parts, are developing the next generation GNSS including GLONASS Galileo and JRANS. And the countries are planning to provide the another GNSS. This research has focused on the next generation GNSS system based on GPS and Galileo system with developing a GNSS simulation software, named as GIMS2005, which generates and analyzes satellite constellation and measurements. Based on the software, a variety of simulation tests have been carried out to recognize limits of GPS-only system and potential benefits of integrated GPS/Galileo positioning In terms of satellite geometry strength and solution accuracy.

  • PDF

GPS/INS AT(Aerial Triangulation) Evaluation According to GPS Processing Time (GPS 위성신호의 처리시간에 따른 GPS/INS 사진기준점측량의 정확도)

  • Lee Seung-Huhn;Wie Gwang-Jae;Kim Seung-Young;Lee Jae-Won
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
    • /
    • 2006.04a
    • /
    • pp.151-158
    • /
    • 2006
  • As GPS 'selective availability' was turned off in 2000, GPS related fields and markets are explosively extended. In mapping area, GPS/INS aided photogrammetry proved it is much cost and time effective method keeping enough accuracy as compared with traditional photogrammetry works. The advantage of GPS/INS integration is interdependence. Even if GPS signal was blocked in some time, the position accuracy is not affected. In this study, various GPS signal time gap was used in GPS/INS AT process. Field surveyed ground points were used in accuracy check with GPS/INS AT check points. And the result showed enough accuracy of photogrammetry work rule of NGII. y.

  • PDF

Development of an Immunosensor to Detect Rat IgG Using Impedance Analyser

  • No D. H.;Kang S.;Kim G. Y.;Chung S. H.;Park Y. H.;Om A. S.;Cho S. I.
    • Agricultural and Biosystems Engineering
    • /
    • v.5 no.1
    • /
    • pp.21-24
    • /
    • 2004
  • Antibody based biosensors are very selective and ultra-sensitive. Antigen-antibody reactions have been used in immunoassays. In this research, a biosensor which uses antigen-antibody reaction was developed to measure and detect rat IgG. Because the antigen-antibody reaction is a physical bounding between antigen and antibody, there are several ways to measure an antigen-antibody reaction. Among the methods, impedance analysis has short measuring time and possibilities of analyzing various properties of the reaction using frequency analysis. Rat IgG could be detected with developed biosensor and impedance analyzer. The biosensor showed good repeatability and availability of detecting concentration changes of rat IgG.

  • PDF

Performance Analysis on GPS RAIM in the Post SA Era

  • Choi, Jae-Won;Lee, Jang-Gyu;Park, Chan-Gook;Jee, Gyu-In
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.56.4-56
    • /
    • 2001
  • Using GPS in the navigation systems such as aviation, maritime and land applications, integrity is considered importantly with accuracy for safety. Integrity monitoring performed in the GPS receiver itself is Receiver Autonomous Integrity Monitoring (RAIM) and need not an independent ground monitoring station. RAIM algorithm uses redundant information when more than four satellites are visible and makes consistency checks between measurement information to alarm users whether the system is operating out of its specified performance limits. Selective Availability (SA) that was used to protect the security interests of the U.S. and its allies by globally denying the full accuracy of the civil system was turned off on May 1, 2000 ...

  • PDF

Enterovirus infection in Korean children and antienteroviral potential candidate agents

  • Park, Kwi Sung;Choi, Young Jin;Park, Joon Soo
    • Clinical and Experimental Pediatrics
    • /
    • v.55 no.10
    • /
    • pp.359-366
    • /
    • 2012
  • Although most enterovirus infections are not serious enough to be life threatening, several enteroviruses such as enterovirus 71 are responsible for severe, potentially life-threatening disease. The epidemic patterns of enteroviruses occur regularly during the year, but they may change due to environmental shifts induced by climate change due to global warming. Therefore, enterovirus epidemiological studies should be performed continuously as a basis for anti-viral studies. A great number of synthesized antiviral compounds that work against enteroviruses have been developed but only a few have demonstrated effectiveness in vivo. No proven effective antiviral agents are available for enterovirus disease therapy. The development of a new antiviral drug is a difficult task due to poor selective toxicity and cost. To overcome these limitations, one approach is to accelerate the availability of other existing antiviral drugs approved for antiviral effect against enteroviruses, and the other way is to screen traditional medicinal plants.

Development of real-time car tracking system with RGPS and its error analysis (RGPS를 이용한 실시간 차량관제시스템 구현과 오차분석)

  • Go, Sun-Jun;Lee, Ja-Sung
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.6 no.1
    • /
    • pp.15-24
    • /
    • 2000
  • Stand-alone global position system receiver based on C/A code tracking generates position error of 100m mainly due to the selective availability and ionospheric and tropospheric delay errors. The differential GPS is the most commonly used method for removing those bias range error components. The relative GPS, although somewhat restrictive in its use, is ideally suited to the car monitoring system for improved Automatic Vehicle location, especially where the DGPS infrastructure is not available. The RGPS does not require any additional hardware, facility or external infrastructure and can be operated within the system with existing host computer and communication link. This paper presents detailed description of the RGPS concept and its implementation for real-time data processing. Performance of RGPS is evaluated with real data and is compared with DGPS.

  • PDF

Ionospheric Modeling at North-East Asia using IGS sites

  • Choi, Byung-Kyu;Park, Jong-Uk;Lee, Sang-Jeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • v.2
    • /
    • pp.195-198
    • /
    • 2006
  • One of the major sources of error in precise GPS positioning since the turn-off the Selective Availability(SA) is the ionospheric propagation delay. For the last decades, a lot of the ionospheric researches based on a GPS network have been implemented throughout the world. Especially researches of the ionospheric modeling for Wide Area Argumentation System(WAAS) have been undertaken and published. In mid-latitude regions, typical spatial and temporal variations in ionospheric models delay tend to minimal. The developed ionospheric model calls for a 1.25 degree grid at latitudes and a 2.5 degree grid at longitudes. The precise grid TEC estimated by the inversion technique is also compared with global ionosphere maps(GIMs) which have been provided by several analysis centers(ACs). The results of initial investigations into the suitability of the proposed ionospheric modeling scheme in north-east Asia are presented.

  • PDF