Studie vedrørende implementering af det fælleseuropæiske togkontrolsystem ETCS på de danske baner

På Aalborg Trafikdage 2002 blev der gjort rede for Banestyrelsens arbejde med implementering af Europæiske radio og togkontrolsystemer (STRATO-projektet, se konferencerapport 2 side 375). Siden da har Banestyrelsen og efter 1. juli 2003 Trafikstyrelsen for Jernbane og Færger arbejdet videre med dette arbejde. Som en væsentlig del af dette arbejde har der været gennemført en samfundsøkonomisk analyse af konsekvenserne ved indføring af de Europæiske radio (GSM-R) og togkontrolsystemer (ETCS) i Danmark. Alle større offentlige investeringer underkastes en samfundsøkonomisk evaluering, og indføringen af et nyt radio- og togkontrolsystem er ingen undtagelse. Det kan dog ofte være vanskeligt at se en større økonomisk fordel ved at udskifte et eksisterende og til dels velfungerende system med et nyt. Alene det faktum at der i en overgangsperiode vil være 2 tekniske systemer i drift, som begge skal drives og vedligeholdes, betyder et væsentligt minus for økonomien ved at udskifte et sy- stem. I den konkrete sag om et europæisk radio- og togkontrolsystem, kunne man godt sige, at en sådan undersøgelse var unødvendig, da Danmark i kraft af sin tiltræden til EU’s direktiver for højhastig- heds- og konventionelle baner, er forpligtiget til at anvende de europæiske systemer ved nyanlæg på og opgraderinger af TEN-strækninger (Trans European Network). Da der imidlertid er mange forskellige måder at implementere de europæiske systemer på, både med hensyn til tekniske niveauer, mulige overgangsløsninger og geografisk udbredelse, har det alligevel været en stor fordel at få gennemført undersøgelsen, således at man har kunnet prioritere en eller flere løsninger i det fremtidige arbejde. Det rådgivende ingeniørfirma NIRAS har i samarbejde med den franske transportrådgiver SYSTRA bistået Banestyrelsen med løsning af opgaven i forbindelse med togkontrol. En tilsva- rende opgave vedr. togradio blev gennemført bistået af ingeniørfirmaet Rambøll

Prevalence and progression of visual impairment in patients newly diagnosed with clinical type 2 diabetes: a 6-year follow up study

<p>Abstract</p> <p>Background</p> <p>Many diabetic patients fear visual loss as the worst consequence of diabetes. In most studies the main eye pathology is assigned as the cause of visual impairment. This study analysed a broad range of possible ocular and non-ocular predictors of visual impairment prospectively in patients newly diagnosed with clinical type 2 diabetes.</p> <p>Methods</p> <p>Data were from a population-based cohort of 1,241 persons newly diagnosed with clinical, often symptomatic type 2 diabetes aged ≥ 40 years. After 6 years, 807 patients were followed up. Standard eye examinations were done by practising ophthalmologists.</p> <p>Results</p> <p>At diabetes diagnosis median age was 65.5 years. Over 6 years, the prevalence of blindness (visual acuity of best seeing eye ≤ 0.1) rose from 0.9% (11/1,241) to 2.4% (19/807) and the prevalence of moderate visual impairment (> 0.1; < 0.5) rose from 5.4% (67/1,241) to 6.7% (54/807). The incidence (95% confidence interval) of blindness was 40.2 (25.3-63.8) per 10,000 patient-years. Baseline predictors of level of visual acuity (age, age-related macular degeneration (AMD), cataract, living alone, low self-rated health, and sedentary life-style) and speed of continued visual loss (age, AMD, diabetic retinopathy (DR), cataract, living alone, and high fasting triglycerides) were identified.</p> <p>Conclusions</p> <p>In a comprehensive assessment of predictors of visual impairment, even in a health care system allowing self-referral to free eye examinations, treatable eye pathologies such as DR and cataract emerge together with age as the most notable predictors of continued visual loss after diabetes diagnosis. Our results underline the importance of eliminating barriers to efficient eye care by increasing patients' and primary care practitioners' awareness of the necessity of regular eye examinations and timely surgical treatment.</p

Fractional Flow Reserve/ Instantaneous Wave-Free Ratio Discordance in Angiographically Intermediate Coronary Stenoses: An Analysis Using Doppler-Derived Coronary Flow Measurements

OBJECTIVES The study sought to determine the coronary flow characteristics of angiographically intermediate stenoses classified as discordant by fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR). BACKGROUND Discordance between FFR and iFR occurs in up to 20% of cases. No comparisons have been reported between the coronary flow characteristics of FFR/iFR discordant and angiographically unobstructed vessels. METHODS Baseline and hyperemic coronary flow velocity and coronary flow reserve (CFR) were compared across 5 vessel groups: FFRþ/iFRþ (108 vessels, n 1�4 91), FFR–/iFRþ (28 vessels, n 1�4 24), FFRþ/iFR– (22 vessels, n 1�4 22), FFR–/iFR– (208 vessels, n 1�4 154), and an unobstructed vessel group (201 vessels, n 1�4 153), in a post hoc analysis of the largest combined pressure and Doppler flow velocity registry (IDEAL [Iberian-Dutch-English] collaborators study). RESULTS FFRdisagreedwithiFRin14%(50of366).Baselineflowvelocitywassimilaracrossall5vesselgroups,includingthe unobstructed vessel group (p 1�4 0.34 for variance). In FFRþ/iFR– discordants, hyperemic flow velocity and CFR were similar to both FFR–/iFR– and unobstructed groups; 37.6 (interquartile range [IQR]: 26.1 to 50.4) cm/s vs. 40.0 [IQR: 29.7 to 52.3] cm/s and 42.2 [IQR: 33.8 to 53.2] cm/s and CFR 2.36 [IQR: 1.93 to 2.81] vs. 2.41 [IQR: 1.84 to 2.94] and 2.50 [IQR: 2.11 to 3.17], respectively (p > 0.05 for all). In FFR–/iFRþ discordants, hyperemic flow velocity, and CFR were similar to the FFRþ/iFRþ group; 28.2 (IQR: 20.5 to 39.7) cm/s versus 23.5 (IQR: 16.4 to 34.9) cm/s and CFR 1.44 (IQR: 1.29 to 1.85) versus 1.39 (IQR: 1.06 to 1.88), respectively (p > 0.05 for all). CONCLUSIONS FFR/iFR disagreement was explained by differences in hyperemic coronary flow velocity. Furthermore, coronary stenoses classified as FFRþ/iFR– demonstrated similar coronary flow characteristics to angiographically unobstructed vessels