Den samfundsøkonomiske værdi af kollektiv transport

DI Transport har bedt COWI gennemføre en analyse af hvilken betydning det ville få for trængslen på vejene og derved for erhvervslivets mobilitet, hvis en del af brugerne i den kollektive trafik i stedet var bilister. I forlængelse heraf skal de samfundsøkonomiske konsekvenser belyses. Analysen adskiller sig fra den normale måde vi ser kollektiv trafik på, hvor vi ikke blot ser på et enkelt projekt, men i stedet ser på om de ændrede omkostninger, der generelt er til driften af den kollektive transport samfundsøkonomisk kan retfærdiggøres gennem øget brug af kollektiv trafik. Omdrejningspunktet for analysen er to scenarier, hvor henholdsvis 10 pct. og 33 pct. af passagererne i den kollektive trafik antages at benytte bilen i stedet. Der er regnet på konsekvenserne for trængslen på vejene og den øgede transporttid som de eksisterende bilister vil blive pålagt, af dette skifte fra bil til kollektiv transport. Scenarierne illustrerer, hvad trængselsomkostningerne ville have været, hvis færre trafikanter benyttede sig af kollektiv transport og i stedet vælger at køre i bil. Dertil er der regnet en samlet samfundsøkonomisk værdi under antagelse af, at reduktionen i antallet af passagerer leder til en reduktion i drift- og vedligeholdelsesomkostningerne til den kollektive transport i samme størrelsesorden

Autumn migration and wintering site of a wood warbler Phylloscopus sibilatrix breeding in Denmark identified using geolocation

Abstract Background Basic knowledge of detailed spatiotemporal migration patterns is lacking for most migratory bird species. Using the smallest available geolocator, we aim to map autumn migration and wintering areas of north European wood warblers Phylloscopus sibilatrix and compare the spatiotemporal pattern with recoveries of individuals ringed across Europe. Results A tracked wood warbler migrated south-south-east to sub-Saharan Africa in Sudan and then west-south-west to winter in Côte d’Ivoire. The timing and route fits well within the distribution of ring recoveries although the westward movement after the Sahara crossing is not revealed by the ring recoveries, but only few recoveries south of Sahara exist. Conclusions The surprising westward movement south of the Sahara supplements the overall pattern revealed by ring recoveries and aids our understanding of the connectivity and site dependence in this generally declining species

Prey diversity is affected by climate and differs between age classes in the Red-backed Shrike (Lanius collurio)

When breeding, food availability is essential for optimal reproductive output and is po-tentially one of the main factors limiting breeding success, especially in single brooded long-distance migratory birds. In this study, we examined the diet (as a measure of prey availability) of two Red-backed Shrike (Lanius collurio) populations in Denmark, based on more than 11,000 prey items covering seven years. We found a negative correlation be-tween prey diversity and temperature, indicating that Red-backed Shrikes feed on pre-ferred prey items in warmer summers (low diversity) while forced to feed on a larger vari-ety of species in colder summers. Adults had a more diverse diet and generally fed on smaller prey items than did young birds. Thus, age-and environment-related differences must be taken into account when describing the diet of the Red-backed Shrike. Direct nest observations produced different results for diet composition than did nest and pellet samples, underlining the importance of using different methods in diet assessments. De-tailed knowledge on limiting factors on the breeding grounds, such as food availability, is crucial for mitigating population declines of vulnerable species, such as the Red-backed Shrike

EN ONSDAG I SEPTEMBER - HISTORIESKRIVER FOR EN DAG

Onsdag den 2. september 1992 blev en af verdenshistoriens bedst dokumenterede dage. Over 51.000 personer indsendte deres dagbog til Nationalmuseet i samarbejde med Danmarks Radio, og de 51.000 prismer at opleve hverdagen i Danmark igennem er bevaret til gavn for eftertiden. Formålet med indsamlingen var foruden at dokumentere den subjektive erfaring at give rum for refleksioner om tid og livets gang. Materialet er i dag en væsentlig kilde til at få indblik i hverdagslivets komplekse livsvilkår, glæder og sorger. Indsamling af dagbøger er blevet en vigtig del af museets arbejde, hvor vægten lægges på personlige erfaringer, samtidsdokumentation og brugerinddragelse. I 2017 blev indsamlingen af dagbøger for en enkelt dag gentaget, hvorved materialet fra 1992 kan aktiveres på nye måder i kommende forskningsprojekter, bl.a. om de forandringer i hverdagslivet, der er sket og sker her og nu.Onsdag den 2. september 1992 blev en af verdenshistoriens bedst dokumenterede dage. Over 51.000 personer indsendte deres dagbog til Nationalmuseet i samarbejde med Danmarks Radio, og de 51.000 prismer at opleve hverdagen i Danmark igennem er bevaret til gavn for eftertiden. Formålet med indsamlingen var foruden at dokumentere den subjektive erfaring at give rum for refleksioner om tid og livets gang. Materialet er i dag en væsentlig kilde til at få indblik i hverdagslivets komplekse livsvilkår, glæder og sorger. Indsamling af dagbøger er blevet en vigtig del af museets arbejde, hvor vægten lægges på personlige erfaringer, samtidsdokumentation og brugerinddragelse. I 2017 blev indsamlingen af dagbøger for en enkelt dag gentaget, hvorved materialet fra 1992 kan aktiveres på nye måder i kommende forskningsprojekter, bl.a. om de forandringer i hverdagslivet, der er sket og sker her og nu

Characteristic Formulae for Timed Automata

This paper offers characteristic formula constructions in the real-time logic L for several behavioural relations between (states of)timed automata. The behavioural relations studied in this work aretimed (bi)similarity, timed ready simulation, faster-than bisimilarityand timed trace inclusion. The characteristic formulae delivered byour constructions have size which is linear in that of the timed automaton they logically describe. This also applies to the characteristicformula for timed bisimulation equivalence, for which an exponentialspace construction was previously offered by Laroussinie, Larsen andWeise

A kinetic model explains why shorter and less affine enzyme-recruiting oligonucleotides can be more potent

Antisense oligonucleotides complementary to RNA targets promise generality and ease of drug design. The first systemically administered antisense drug was recently approved for treatment and others are in clinical development. Chemical modifications that increase the hybridization affinity of oligonucleotides are reasoned to confer higher potency, i.e., modified oligonucleotides can be dosed at lower concentrations to achieve the same effect. Surprisingly, shorter and less affine oligonucleotides sometimes display increased potency. To explain this apparent contradiction, increased uptake or decreased propensity to form structures have been suggested as possible mechanisms. Here, we provide an alternative explanation that invokes only the kinetics behind oligonucleotide-mediated cleavage of RNA targets. A model based on the law of mass action predicts, and experiments support, the existence of an optimal binding affinity. Exaggerated affinity, and not length per se, is detrimental to potency. This finding clarifies how to optimally apply high-affinity modifications in the discovery of potent antisense oligonucleotide drugs

Easily denaturing nucleic acids derived from intercalating nucleic acids: thermal stability studies, dual duplex invasion and inhibition of transcription start

The bulged insertions of (R)-1-O-(pyren-1-ylmethyl)glycerol (monomer P) in two complementary 8mer DNA strands (intercalating nucleic acids) opposite to each other resulted in the formation of an easily denaturing duplex, which had lower thermal stability (21.0°C) than the wild-type double-stranded DNA (dsDNA, 26.0°C), but both modified oligodeoxynucleotides had increased binding affinity toward complementary single-stranded DNA (ssDNA) (41.5 and 39.0°C). Zipping of pyrene moieties in an easily denaturing duplex gave formation of a strong excimer band at 480 nm upon excitation at 343 nm in the steady-state fluorescence spectra. The excimer band disappeared upon addition of a similar short dsDNA, but remained when adding a 128mer dsDNA containing the same sequence. When P was inserted into 2′-OMe-RNA strands, the duplex with zipping P was found to be more stable (42.0°C) than duplexes with the complementary ssDNAs (31.5 and 19.5°C). The excimer band observed in the ds2′-OMe-RNA with zipping P had marginal changes upon addition of both 8 and 128mer dsDNA. Synthesized oligonucleotides were tested in a transcriptional inhibition assay for targeting of the open complex formed by Escherichia coli RNA polymerase with the lac UV-5 promoter using the above mentioned 128mer dsDNA. Inhibition of transcription was observed for 8mer DNAs possessing pyrene intercalators and designed to target both template and non-template DNA strands within the open complex. The observed inhibition was partly a result of unspecific binding of the modified DNAs to the RNA polymerase. Furthermore, the addition of 8mer DNA with three bulged insertions of P designed to be complementary to the template strand at the +36 to +43 position downstream of the transcription start resulted in a specific halt of transcription producing a truncated RNA transcript. This is to our knowledge the first report of an RNA elongation stop mediated by a small DNA sequence possessing intercalators. The insertions of P opposite to each other in ds2′-OMe-RNA showed inhibition efficiency of 96% compared with 25% for unmodified ds2′-OMe-RNA