278 research outputs found
Financial Crises and Economic Activity
We study the output costs of 40 systemic banking crises since 1980. Most, but not all, crises in our sample coincide with a sharp contraction in output from which it took several years to recover. Our main findings are as follows. First, the current financial crisis is unlike any others in terms of a wide range of economic factors. Second, the output losses of past banking crises were higher when they were accompanied by a currency crisis or when growth was low at the onset of the crisis. When accompanied by a sovereign debt default, a systemic banking crisis was less costly. And, third, there is a tendency for systemic banking crises to have lasting negative output effects.
Policy insights and modelling challenges: The case of passenger car powertrain technology transition in the European Union
Purpose: We are interested in what policy insights can be transferred from EU countries that have been most successful in introducing EVs to those that are debating policy options. As we use a model to explore this, we are also interested in the application of modelling, seeking to understand if real world policies and results can be replicated in a model and, more generally, the challenges to the use of modelling in policy appraisal. Methods: We use the EC-JRC Powertrain Technology Transition Market Agent Model (PTTMAM), a system dynamics model based around the interactions of conceptual market agent groups in the EU. We perform iterative scenario tests to replicate the policies carried out in the Netherlands and the UK in recent years in an attempt to achieve similar results in EV sales. We then transfer the policy scenarios to other EU member states and assess the transferability of the policies. Results: Reasonable approximations of the Netherlands and UK EV policies and sales were achieved and implemented in other EU member states. Conclusion: We find that the PTTMAM is fit-for-purpose and can replicate successful policies to a certain degree. Policy success is sensitive to country specific conditions, and a system dynamics model like the PTTMAM can help identify which conditions react to which policy stimulus. There are challenges to modelling in policy appraisal, such as the subjectivity of the modeller and flexibility to specific conditions, which must be kept transparent for the model to be a relevant tool for policy making
Adaptive evolution of drug targets in producer and non-producer organisms
Mycophenolic acid (MPA) is an immunosuppressive drug produced by several fungi in Penicillium subgenus Penicillium. This toxic metabolite is an inhibitor of IMP dehydrogenase (IMPDH). The MPA biosynthetic cluster of P. brevicompactum contains a gene encoding a B-type IMPDH, IMPDH-B, which confers MPA-resistance. Surprisingly, all members of subgenus Penicillium contain genes encoding IMPDHs of both the A and B type, regardless of their ability to produce MPA. Duplication of the IMPDH gene occurred prior to and independent of the acquisition of the MPA biosynthetic cluster. Both P. brevicompactum IMPDHs are MPA-resistant while the IMPDHs from a nonproducer are MPA-sensitive. Resistance comes with a catalytic cost: while P. brevicompactum IMPDH-B is >1000-fold more resistant to MPA than a typical eukaryotic IMPDH, its value of k(cat)/K(m) is 0.5% of “normal”. Curiously, IMPDH-B of Penicillium chrysogenum, which does not produce MPA, is also a very poor enzyme. The MPA binding site is completely conserved among sensitive and resistant IMPDHs. Mutational analysis shows that the C-terminal segment is a major structural determinant of resistance. These observations suggest that the duplication of the IMPDH gene in Pencillium subgenus Penicillium was permissive for MPA production and that MPA production created a selective pressure on IMPDH evolution. Perhaps MPA production rescued IMPDH-B from deleterious genetic drift
The governance of justice and internal security in Scotland: Between the Scottish independence referendum and British decisions on the EU
This article examines how the governance of justice and internal security in Scotland could be affected by the outcome of the Scottish independence referendum in September 2014. The article argues that it is currently impossible to equate a specific result in the referendum with a given outcome for the governance of justice and internal security in Scotland. This is because of the complexities of the current arrangements in that policy area and the existence of several changes that presently affect them and are outside the control of the government and of the people of Scotland. This article also identifies an important paradox. In the policy domain of justice and internal security, a ‘no’ vote could, in a specific set of circumstances, actually lead to more changes than a victory of the ‘yes’ camp
Methyl-binding domain protein-based DNA isolation from human blood serum combines DNA analyses and serum-autoantibody testing
<p>Abstract</p> <p>Background</p> <p>Circulating cell free DNA in serum as well as serum-autoantibodies and the serum proteome have great potential to contribute to early cancer diagnostics via non invasive blood tests. However, most DNA preparation protocols destroy the protein fraction and therefore do not allow subsequent protein analyses. In this study a novel approach based on methyl binding domain protein (MBD) is described to overcome the technical difficulties of combining DNA and protein analysis out of one single serum sample.</p> <p>Methods</p> <p>Serum or plasma samples from 98 control individuals and 54 breast cancer patients were evaluated upon silica membrane- or MBD affinity-based DNA isolation via qPCR targeting potential DNA methylation markers as well as by protein-microarrays for tumor-autoantibody testing.</p> <p>Results</p> <p>In control individuals, an average DNA level of 22.8 ± 25.7 ng/ml was detected applying the silica membrane based protocol and 8.5 ± 7.5 ng/ml using the MBD-approach, both values strongly dependent on the serum sample preparation methods used. In contrast to malignant and benign tumor serum samples, cell free DNA concentrations were significantly elevated in sera of metastasizing breast cancer patients. Technical evaluation revealed that serum upon MBD-based DNA isolation is suitable for protein-array analyses when data are consistent to untreated serum samples.</p> <p>Conclusion</p> <p>MBD affinity purification allows DNA isolations under native conditions retaining the protein function, thus for example enabling combined analyses of DNA methylation and autoantigene-profiles from the same serum sample and thereby improving minimal invasive diagnostics.</p
Testing Simulation Theory with Cross-Modal Multivariate Classification of fMRI Data
The discovery of mirror neurons has suggested a potential neural basis for simulation and common coding theories of action perception, theories which propose that we understand other people's actions because perceiving their actions activates some of our neurons in much the same way as when we perform the actions. We propose testing this model directly in humans with functional magnetic resonance imaging (fMRI) by means of cross-modal classification. Cross-modal classification evaluates whether a classifier that has learned to separate stimuli in the sensory domain can also separate the stimuli in the motor domain. Successful classification provides support for simulation theories because it means that the fMRI signal, and presumably brain activity, is similar when perceiving and performing actions. In this paper we demonstrate the feasibility of the technique by showing that classifiers which have learned to discriminate whether a participant heard a hand or a mouth action, based on the activity patterns in the premotor cortex, can also determine, without additional training, whether the participant executed a hand or mouth action. This provides direct evidence that, while perceiving others' actions, (1) the pattern of activity in premotor voxels with sensory properties is a significant source of information regarding the nature of these actions, and (2) that this information shares a common code with motor execution
Ancient genomes reveal a high diversity of Mycobacterium leprae in medieval Europe.
Studying ancient DNA allows us to retrace the evolutionary history of human pathogens, such as Mycobacterium leprae, the main causative agent of leprosy. Leprosy is one of the oldest recorded and most stigmatizing diseases in human history. The disease was prevalent in Europe until the 16th century and is still endemic in many countries with over 200,000 new cases reported annually. Previous worldwide studies on modern and European medieval M. leprae genomes revealed that they cluster into several distinct branches of which two were present in medieval Northwestern Europe. In this study, we analyzed 10 new medieval M. leprae genomes including the so far oldest M. leprae genome from one of the earliest known cases of leprosy in the United Kingdom-a skeleton from the Great Chesterford cemetery with a calibrated age of 415-545 C.E. This dataset provides a genetic time transect of M. leprae diversity in Europe over the past 1500 years. We find M. leprae strains from four distinct branches to be present in the Early Medieval Period, and strains from three different branches were detected within a single cemetery from the High Medieval Period. Altogether these findings suggest a higher genetic diversity of M. leprae strains in medieval Europe at various time points than previously assumed. The resulting more complex picture of the past phylogeography of leprosy in Europe impacts current phylogeographical models of M. leprae dissemination. It suggests alternative models for the past spread of leprosy such as a wide spread prevalence of strains from different branches in Eurasia already in Antiquity or maybe even an origin in Western Eurasia. Furthermore, these results highlight how studying ancient M. leprae strains improves understanding the history of leprosy worldwide
Jets and energy flow in photon-proton collisions at HERA
Properties of the hadronic final state in photoproduction events with large transverse energy are studied at the electron-proton collider HERA. Distributions of the transverse energy, jets and underlying event energy are compared to \overline{p}p data and QCD calculations. The comparisons show that the \gamma p events can be consistently described by QCD models including -- in addition to the primary hard scattering process -- interactions between the two beam remnants. The differential jet cross sections d\sigma/dE_T^{jet} and d\sigma/d\eta^{jet} are measured
Разработка интерактивной моделирующей системы технологии низкотемпературной сепарации газа
We present a study of J ψ meson production in collisions of 26.7 GeV electrons with 820 GeV protons, performed with the H1-detector at the HERA collider at DESY. The J ψ mesons are detected via their leptonic decays both to electrons and muons. Requiring exactly two particles in the detector, a cross section of σ(ep → J ψ X) = (8.8±2.0±2.2) nb is determined for 30 GeV ≤ W γp ≤ 180 GeV and Q 2 ≲ 4 GeV 2 . Using the flux of quasi-real photons with Q 2 ≲ 4 GeV 2 , a total production cross section of σ ( γp → J / ψX ) = (56±13±14) nb is derived at an average W γp =90 GeV. The distribution of the squared momentum transfer t from the proton to the J ψ can be fitted using an exponential exp(− b ∥ t ∥) below a ∥ t ∥ of 0.75 GeV 2 yielding a slope parameter of b = (4.7±1.9) GeV −2
Gender-Specific Effects of Unemployment on Family Formation: A Cross-National Perspective
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