1,356,790 research outputs found
Radiative penguin decays at BABAR
No full textWe report preliminary results based on a data sample of 20.7 fb^(-1) recorded at the Υ(4S) resonance by the BABAR detector at the PEP-II energy asymmetric collider at the Stanford Linear Accelerator Center. We have measured the branching fraction B(B^0→K^(*0)γ)=(4.39±0.41±0.27)×10^(–5) and measured a charge asymmetry in the B→K^*γ decays consistent with zero: A_(CP)=–0.035±0.076±0.012. We also searched for the decay B^0 →γγ and placed the 90% C.L. limit B(B^0 →γγ)<1.7×10^(-6). The search for the electroweak penguin decays B→K^(*)l^(+)l^(-) yielded the limits B(B→Kl^(+)l^(-))<0.6×10^(-6) and B(B→K*l^(+)l^(-))<2.5×10^(-6) at the 90% C.L
A Cost-benefit Analysis of Cykellänken Ryd
No full textDuring the winter of 2018, the bicycle path named Cykellänken Ryd was completed. The path extends from central Ryd to the city center of Linköping. According to the municipality of Linköping, Cykellänken Ryd is one out of two pilot projects which is meant to be evaluated and used to support the decision-making process of whether seven other planned bicycle paths is to be constructed. The municipality politicians have however, already decided for at least one additional bike path to be built, despite the lack of an evaluation of whether the pilot projects have been cost-effective. The purpose of this composition is to create a cost-benefit analysis of Cykellänken Ryd and estimate whether the project has been economically profitable. Based on the result, we have discussed whether another planned bicycle path is likely to be profitable. The bicycle path we will discuss is planned to be built between Hjulsbro and Linköping city center and is currently up for decision. In order to produce a result, an estimation regarding the positive and negative effects of the bicycle path has been made. By using ASEK and GC-kalk we have been able to estimate the monetary effects in order to compare the costs with the benefits. According to our calculations, Cykellänken Ryd is estimated to have a net-benefit of 61 501 142 SEK, and has therefore been profitable. We have also taken monetarily immeasurable effects into consideration. In order for the project to be unprofitable, these effects would have to exceed 61 501 142 SEK. The existing bicycle path between Hjulsbro and Linköping city center is currently used by 639 871 bicycle rides per year. The costs for the new bicycle path to Hjulsbro is expected to be higher than the cost of Cykellänken Ryd. However, due to the increased volume of cyclists it is also expected to produce higher benefits in the cost-benefit analysis. During the composition, we have had to make certain assumptions due to the lack of figures from the municipalities automatic bicycle counters and an absence of other information. Among others we lack the specific number of bicycle rides before the project were initiated, which is important to keep in mind.Vintern 2018 stod Cykellänken Ryd färdig. Vägen sträcker sig från Ryds centrum till Linköpings innerstad. Enligt Linköpings kommun är Cykellänken Ryd ett av två stycken pilotprojekt som ska utvärderas för att sedan användas som beslutsunderlag för de andra sju planerade cykellänkarna i kommunen. Politikerna i Linköpings kommun har beslutat att minst en av de andra cykellänkarna ska byggas trots att det inte finns någon utvärdering över huruvida pilotprojekten är kostnadseffektiva eller ej. Syftet med uppsatsen var således att genomföra en samhällsekonomisk kalkyl på Cykellänken Ryd för att se om projektet är lönsamt. Utifrån detta resultat resonerades det sedan kring huruvida en annan cykellänk kommer vara lönsam eller inte. Cykellänken som jämfördes med Cykellänken Ryd ska gå mellan Hjulsbro och innerstaden och är beslutsaktuell. För att få fram ett resultat identifierade och kvantifierade vide positiva och negativa effekter som cykellänken har medfört. Med hjälp av ASEK och GC-kalk värderade vi sedan effekterna monetärt för att kunna väga kostnader mot nyttor. Enligt vår kalkyl har projektet Cykellänken Ryd medfört en nettonytta motsvarande 61 501 142 kr och alltså varit lönsam. Det finns även effekter som har varit svåra att värdera monetärt. För att projektet ska vara olönsamt krävs det alltså att dessa effekter utgör en kostnad på minst 61 501 142 kr. Den planerade cykellänken mellan Hjulsbro och innerstaden har ett cykelflöde som uppgår till 639 871 cykelresor per år vilket är mer än dubbelt så många jämfört med Cykellänken Ryd. De planerade kostnaderna är högre för cykellänken Hjulsbro än för Cykellänken Ryd men vi gjorde ändå bedömningen att projektet borde visa ett positivt resultat just för att det höga cykelflödet kommer medföra höga nyttoposter i kalkylen. Under uppsatsen gjordes vissa antagningar i brist på uppgifter från cykelräknare samt övrig information. Det innebar bland annat att vi inte har fått ett exakt antal cykelresor att utgå från vilket är viktigt att ha i åtanke.
RyD investment and financial frictions
No full textRyD intensity for small firms is high and persistent over time. At the same time, small firms are often financially constrained. This paper proposes a theoretical model that explains the coexistence of these two stylized facts. It is shown that self-fina
A combined RSA and FE study of the implanted proximal tibia: correlation of the post-operative mechanical environment with implant migration
No full textInter-patient evaluation of stresses in proximal implanted tibiae
No full textIn biomechanics finite element analysis (FEA) is still only a comparative tool. To the authors' knowledge, no study has examined multiple tibiae or included patient specific data. Only by constructing finite element models taking into account these parameters in combination with prospective clinical studies can the predictive power of FEA be assessed. The purpose of this study was to evaluate the differences in the predicted stresses and risk ratios observed on the resected surface of models of proximal implanted tibiae created from patient specific data.
Finite element models of four proximal implanted tibiae were analysed. The models were created from quantitative computed tomography (QCT) data. The immediate post-operative situation was modelled by assuming frictionless contact between the tibia and the tibial plateau. Post-operative alignment of the implants were considered in the study. The loads used in the models were equivalent to three times the weight of each patient. A bi-condylar load case was used, in which 60% of the total force was applied on the medial side and 40% on the lateral side. The forces were applied directly on the tibial plateau.
A program called Bonemat, was used to assign the material properties on an element-by-element basis, based on the correlation between QCT data and the material properties of the bone (i.e. apparent density and stiffness). Meshes of linear tetrahedral elements were created in I-DEAS for both bone and implant. Risk ratio values (defined as the Von Mises stress divided by the ultimate compressive strength) on the resected surface of each tibia were examined and compared between all four models. All the analyses were carried out using MARC K7.3.2.
In all four models, a similar overall risk ratio distribution on the surface of interest was observed, with peak values of 319%, 315%, 322% and 327% for patients 1,2,3 and 4, respectively. In all the models, the peak values were found in the portion of cancellous bone supporting the posterior side of the tibial plateau.
For all four tibiae there were areas of bone, particularly around the posterior cruciate cut-out, where the localised risk of failure was high. However, in general, the risk of failure was below 100% over the majority of the resected surface. RSA studies of tibial plateaus have shown that during the first six months after surgery, there is a period of rapid migration. This is widely thought to be due to the implant "bedding in". The findings of this study support this view, as some regions presented considerably high risk ratios. In these regions, the cancellous bone will be crushed and the load redistributed on the resected surface until an equilibrium position is reached. This study has shown that patient specific FE model do demonstrate subtle differences in the predicted stress and risk ratio distributions. This emphasises the importance of moving away from the traditional generic modelling approach to patient specific modelling
A combined RSA and FE study of the implanted proximal tibia: correlation of the post-operative mechanical environment with implant migration
No full textThere is strong evidence to suggest that inducible displacements, migration and implant loosening are closely related to the initial mechanical environment of the implanted tibia. If this is true, then it should be possible to predict the likelihood of implant migration using patient-specific finite element models. Finite element models of the proximal implanted tibiae were analysed based on pre-operative quantitative computed tomography data of four patients entered into a radiographic migration study. These four patients were also part of an radiostereometric analysis (RSA) study. A variety of load cases were analysed and the risk of bone failure determined for a 2 mm layer of bone immediately beneath the tibial tray. The results were compared with the RSA data measured 1 year post-operatively for each patient. For each patient, an appropriate load case was selected based on patient weight and on the varus–valgus migrations observed in the migration study. The two patients with press-fit implants were predicted to have the highest risk of failure and were found to migrate the most. The two patients with bonded implants (one HA coated and one cemented) were found to have a low risk of failure and these implants migrated the least.This study suggests that the degree of implant migration is dependent on the initial mechanical environment and can be determined using patient-specific finite element analysis
Evidence for a Hard Ionizing Spectrum from a
No full textWe present the Magellan/FIRE detection of highly ionized C iv λ1550 and O iii]λ1666 in a deep infrared spectrum of the z = 6.11 gravitationally lensed low-mass galaxy RXC J2248.7-4431-ID3, which has previously known Lyα. No corresponding emission is detected at the expected location of He ii λ1640. The upper limit on He ii, paired with detection of O iii] and C iv, constrains possible ionization scenarios. Production of C iv and O iii] requires ionizing photons of 2.5–3.5 Ryd, but once in that state their multiplet emission is powered by collisional excitation at lower energies (~0.5 Ryd). As a pure recombination line, He ii emission is powered by 4 Ryd ionizing photons. The data therefore require a spectrum with significant power at 3.5 Ryd but a rapid drop toward 4.0 Ryd. This hard spectrum with a steep drop is characteristic of low-metallicity stellar populations, and less consistent with soft AGN excitation, which features more 4 Ryd photons and hence higher He ii flux. The conclusions based on ratios of metal line detections to helium non-detection are strengthened if the gas metallicity is low. RXJ2248-ID3 adds to the growing handful of reionization-era galaxies with UV emission line ratios distinct from the general z=2-3 population in a way that suggests hard ionizing spectra that do not necessarily originate in AGNs.National Science Foundation (U.S.) (AST-1410155
Catalogus annorum et principum sive monarcharum mundi geminus plerisque in locis obcurioribus illustratus & in caelebrioribus locuoletatus atque a mendis, recognitione diligenti repurgatus, cum accessione multorum aliorum que in priori aeditione non continebantur, quemadmodum suis locis toto libro uidere licebit, ab homine conditio, usque in praesentem, a nato Christo, millesimum quingentesimum & quinquagesimum annum deductus & continuatus
No full textper D. Valerium Anselmum RydDruckermarken von Apiarius auf Titelseite und letzter Seit
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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