8 research outputs found

    API 616 Gas Turbine

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    Retinal Vascular Occlusion after COVID-19 Vaccination : More Coincidence than Causal Relationship? Data from a Retrospective Multicentre Study

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    Background: To investigate whether vaccination against SARS-CoV-2 is associated with the onset of retinal vascular occlusive disease (RVOD). Methods: In this multicentre study, data from patients with central and branch retinal vein occlusion (CRVO and BRVO), central and branch retinal artery occlusion (CRAO and BRAO), and anterior ischaemic optic neuropathy (AION) were retrospectively collected during a 2-month index period (1 June–31 July 2021) according to a defined protocol. The relation to any previous vaccination was documented for the consecutive case series. Numbers of RVOD and COVID-19 vaccination were investigated in a case-by-case analysis. A case– control study using age- and sex-matched controls from the general population (study participants from the Gutenberg Health Study) and an adjusted conditional logistic regression analysis was conducted. Results: Four hundred and twenty-one subjects presenting during the index period (61 days) were enrolled: one hundred and twenty-one patients with CRVO, seventy-five with BRVO, fifty-six with CRAO, sixty-five with BRAO, and one hundred and four with AION. Three hundred and thirty-two (78.9%) patients had been vaccinated before the onset of RVOD. The vaccines given were BNT162b2/BioNTech/Pfizer (n = 221), followed by ChadOx1/AstraZeneca (n = 57), mRNA1273/Moderna (n = 21), and Ad26.COV2.S/Johnson & Johnson (n = 11; unknown n = 22). Our case–control analysis integrating population-based data from the GHS yielded no evidence of an increased risk after COVID-19 vaccination (OR = 0.93; 95% CI: 0.60–1.45, p = 0.75) in connection with a vaccination within a 4-week window. Conclusions: To date, there has been no evidence of any association between SARS-CoV-2 vaccination and a higher RVOD risk

    GT 2008-50840 AERODERIVATIVE GAS TURBINES FOR LNG LIQUEFACTION PLANTS - PART 2: WORLD'S FIRST APPLICATION AND OPERATING EXPERIENCE

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    ABSTRACT LNG market pressures for thermally efficient and environmentally friendly LNG plants coupled with the need for high plant availability have resulted in the world's first application of high performance aeroderivative gas turbines for a 3.7 MTPA LNG plant in Darwin. The six engines utilized are GE PGT25+ engines rated at 32 MW ISO driving propane, ethylene and methane compressors. The paper describes the design, manufacture, testing, and implementation of these units focusing on both the gas turbine and the centrifugal compressors. Power augmentation utilized on these units is also discussed. An overview of operating experience and lessons learned are provided. Part 1 of this paper provides a detailed analysis of why high thermal efficiency is important for LNG plants from an economic and greenhouse gas perspective

    Combined Torsional And Electromechanical Analysis Of An Lng Compression Train With Variable Speed Drive System.

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    Lecturepg. 93-102Nowadays variable speed drive systems (VSDS) are preferred to constant speed drives in the oil and gas industry because they can improve the efficiency of the process while avoiding the use of complex mechanical mechanisms (e.g., guide vanes) or plant recycling and throttling. However, the reputation of VSDS has not always been favorable since they can be a cause of torsional vibration problems. This is mainly due to the intrinsic nature of switching-based electrical systems to produce pulsating torque ripple on the shaft. In addition, closed-loop electromechanical interactions could lead to system instability. The aim of this paper is to introduce a new combined approach to deal with torsional phenomena, especially in high shaft-power applications such as liquefied natural gas (LNG) trains. Besides the conventional shaft-line modal analysis, a precise understanding of the electromechanical interactions in achieved through combined simulations between the shaft-line designer (compressor manufacturer) and the VSDS supplier together with a full-load-full-speed (FLFS) train string test. Simulations and string test results confirmed satisfactory torsional behavior and electromechanical stability of the overall system

    Retinal Vascular Occlusion after COVID-19 Vaccination: More Coincidence than Causal Relationship? Data from a Retrospective Multicentre Study

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    Background: To investigate whether vaccination against SARS-CoV-2 is associated with the onset of retinal vascular occlusive disease (RVOD). Methods: In this multicentre study, data from patients with central and branch retinal vein occlusion (CRVO and BRVO), central and branch retinal artery occlusion (CRAO and BRAO), and anterior ischaemic optic neuropathy (AION) were retrospectively collected during a 2-month index period (1 June–31 July 2021) according to a defined protocol. The relation to any previous vaccination was documented for the consecutive case series. Numbers of RVOD and COVID-19 vaccination were investigated in a case-by-case analysis. A case– control study using age- and sex-matched controls from the general population (study participants from the Gutenberg Health Study) and an adjusted conditional logistic regression analysis was conducted. Results: Four hundred and twenty-one subjects presenting during the index period (61 days) were enrolled: one hundred and twenty-one patients with CRVO, seventy-five with BRVO, fifty-six with CRAO, sixty-five with BRAO, and one hundred and four with AION. Three hundred and thirty-two (78.9%) patients had been vaccinated before the onset of RVOD. The vaccines given were BNT162b2/BioNTech/Pfizer (n = 221), followed by ChadOx1/AstraZeneca (n = 57), mRNA- 1273/Moderna (n = 21), and Ad26.COV2.S/Johnson & Johnson (n = 11; unknown n = 22). Our case–control analysis integrating population-based data from the GHS yielded no evidence of an increased risk after COVID-19 vaccination (OR = 0.93; 95% CI: 0.60–1.45, p = 0.75) in connection with a vaccination within a 4-week window. Conclusions: To date, there has been no evidence of any association between SARS-CoV-2 vaccination and a higher RVOD risk

    Retinal Vascular Occlusion after COVID-19 Vaccination: More Coincidence than Causal Relationship? Data from a Retrospective Multicentre Study

    No full text
    Background: To investigate whether vaccination against SARS-CoV-2 is associated with the onset of retinal vascular occlusive disease (RVOD). Methods: In this multicentre study, data from patients with central and branch retinal vein occlusion (CRVO and BRVO), central and branch retinal artery occlusion (CRAO and BRAO), and anterior ischaemic optic neuropathy (AION) were retrospectively collected during a 2-month index period (1 June–31 July 2021) according to a defined protocol. The relation to any previous vaccination was documented for the consecutive case series. Numbers of RVOD and COVID-19 vaccination were investigated in a case-by-case analysis. A case–control study using age- and sex-matched controls from the general population (study participants from the Gutenberg Health Study) and an adjusted conditional logistic regression analysis was conducted. Results: Four hundred and twenty-one subjects presenting during the index period (61 days) were enrolled: one hundred and twenty-one patients with CRVO, seventy-five with BRVO, fifty-six with CRAO, sixty-five with BRAO, and one hundred and four with AION. Three hundred and thirty-two (78.9%) patients had been vaccinated before the onset of RVOD. The vaccines given were BNT162b2/BioNTech/Pfizer (n = 221), followed by ChadOx1/AstraZeneca (n = 57), mRNA-1273/Moderna (n = 21), and Ad26.COV2.S/Johnson & Johnson (n = 11; unknown n = 22). Our case–control analysis integrating population-based data from the GHS yielded no evidence of an increased risk after COVID-19 vaccination (OR = 0.93; 95% CI: 0.60–1.45, p = 0.75) in connection with a vaccination within a 4-week window. Conclusions: To date, there has been no evidence of any association between SARS-CoV-2 vaccination and a higher RVOD risk

    Retinal Vascular Occlusion after COVID-19 Vaccination: More Coincidence than Causal Relationship? Data from a Retrospective Multicentre Study

    No full text
    Background: To investigate whether vaccination against SARS-CoV-2 is associated with the onset of retinal vascular occlusive disease (RVOD). Methods: In this multicentre study, data from patients with central and branch retinal vein occlusion (CRVO and BRVO), central and branch retinal artery occlusion (CRAO and BRAO), and anterior ischaemic optic neuropathy (AION) were retrospectively collected during a 2-month index period (1 June–31 July 2021) according to a defined protocol. The relation to any previous vaccination was documented for the consecutive case series. Numbers of RVOD and COVID-19 vaccination were investigated in a case-by-case analysis. A case– control study using age- and sex-matched controls from the general population (study participants from the Gutenberg Health Study) and an adjusted conditional logistic regression analysis was conducted. Results: Four hundred and twenty-one subjects presenting during the index period (61 days) were enrolled: one hundred and twenty-one patients with CRVO, seventy-five with BRVO, fifty-six with CRAO, sixty-five with BRAO, and one hundred and four with AION. Three hundred and thirty-two (78.9%) patients had been vaccinated before the onset of RVOD. The vaccines given were BNT162b2/BioNTech/Pfizer (n = 221), followed by ChadOx1/AstraZeneca (n = 57), mRNA- 1273/Moderna (n = 21), and Ad26.COV2.S/Johnson & Johnson (n = 11; unknown n = 22). Our case–control analysis integrating population-based data from the GHS yielded no evidence of an increased risk after COVID-19 vaccination (OR = 0.93; 95% CI: 0.60–1.45, p = 0.75) in connection with a vaccination within a 4-week window. Conclusions: To date, there has been no evidence of any association between SARS-CoV-2 vaccination and a higher RVOD risk
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