Greenhouse gases and climatic states of minimum entropy production

The hypothesis of minimum entropy production is applied to a simple one-dimensional energy balance model and is analysed for different values of the radiative forcing due to greenhouse gases. The extremum principle is used to determine the planetary “conductivity” and to avoid the “diffusive” approximation, which is commonly assumed in this type of model. For present conditions the result at minimum radiative entropy production is similar to that obtained by applying the classical model. Other climatic scenarios show visible differences, with better behaviour for the extremal case

Distributed all-atom simulations of intrinsically unstructured proteins

The Computational Biophysics Group at the Universitat Pompeu Fabra (GRIB-UPF) hosts two unique computational resources dedicated to the execution of large scale molecular dynamics (MD) simulations: (a) the ACMD molecular-dynamics software, used on standard personal computers with graphical processing units (GPUs); and (b) the GPUGRID. net computing network, supported by users distributed worldwide that volunteer GPUs for biomedical research. We leveraged these resources and developed studies, protocols and open-source software to elucidate energetics and pathways of a number of biomolecular systems, with a special focus on flexible proteins with many degrees of freedom. First, we characterized ion permeation through the bactericidal model protein Gramicidin A conducting one of the largest studies to date with the steered MD biasing methodology. Next, we addressed an open problem in structural biology, the determination of drug-protein association kinetics; we reconstructed the binding free energy, association, and dissaciociation rates of a drug like model system through a spatial decomposition and a Makov-chain analysis. The work was published in the Proceedings of the National Academy of Sciences and become one of the few landmark papers elucidating a ligand-binding pathway. Furthermore, we investigated the unstructured Kinase Inducible Domain (KID), a 28-peptide central to signalling and transcriptional response; the kinetics of this challenging system was modelled with a Markovian approach in collaboration with Frank Noe’s group at the Freie University of Berlin. The impact of the funding includes three peer-reviewed publication on high-impact journals; three more papers under review; four MD analysis components, released as open-source software; MD protocols; didactic material, and code for the hosting group.

Methodology for studying the numerical speed of sound in finite differences schemes

The space and time discretization inherent to all FDTD schemesintroduce non-physical dispersion errors, i.e. deviations ofthe speed of sound from the theoretical value predicted bythe governing Euler differential equations. A generalmethodologyfor computing this dispersion error via straightforwardnumerical simulations of the FDTD schemes is presented.The method is shown to provide remarkable accuraciesof the order of 1/1000 in a wide variety of twodimensionalfinite difference schemes.

Effects of long-term averaging of quantitative blood pressure traits on the detection of genetic associations.

Blood pressure (BP) is a heritable, quantitative trait with intraindividual variability and susceptibility to measurement error. Genetic studies of BP generally use single-visit measurements and thus cannot remove variability occurring over months or years. We leveraged the idea that averaging BP measured across time would improve phenotypic accuracy and thereby increase statistical power to detect genetic associations. We studied systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP) averaged over multiple years in 46,629 individuals of European ancestry. We identified 39 trait-variant associations across 19 independent loci (p < 5 × 10(-8)); five associations (in four loci) uniquely identified by our LTA analyses included those of SBP and MAP at 2p23 (rs1275988, near KCNK3), DBP at 2q11.2 (rs7599598, in FER1L5), and PP at 6p21 (rs10948071, near CRIP3) and 7p13 (rs2949837, near IGFBP3). Replication analyses conducted in cohorts with single-visit BP data showed positive replication of associations and a nominal association (p < 0.05). We estimated a 20% gain in statistical power with long-term average (LTA) as compared to single-visit BP association studies. Using LTA analysis, we identified genetic loci influencing BP. LTA might be one way of increasing the power of genetic associations for continuous traits in extant samples for other phenotypes that are measured serially over time.

A longitudinal study of environmental tobacco smoke exposure in children: parental self reports versus age dependent biomarkers

Background: Awareness of the negative effects of smoking on children's health prompted a decrease in the self-reporting of parental tobacco use in periodic surveys from most industrialized countries. Our aim is to assess changes between ETS exposure at the end of pregnancy and at 4 years of age determined by the parents' self-report and measurement of cotinine in age related biological matrices.Methods: The prospective birth cohort included 487 infants from Barcelona city (Spain). Mothers were asked about maternal and household smoking habit. Cord serum and children's urinary cotinine were analyzed in duplicate using a double antibody radioimmunoassay. Results: At 4 years of age, the median urinary cotinine level in children increased 1.4 or 3.5 times when father or mother smoked, respectively. Cotinine levels in children's urine statistically differentiated children from smoking mothers (Geometric Mean (GM) 19.7 ng/ml; 95% CI 16.83–23.01) and exposed homes (GM 7.1 ng/ml; 95% CI 5.61–8.99) compared with non-exposed homes (GM 4.5 ng/ml; 95% CI 3.71–5.48). Maternal self-reported ETS exposure in homes declined in the four year span between the two time periods from 42.2% to 31.0% (p < 0.01). Nevertheless, most of the children considered non-exposed by their mothers had detectable levels of cotinine above 1 ng/mL in their urine.Conclusion: We concluded that cotinine levels determined in cord blood and urine, respectively, were useful for categorizing the children exposed to smoking and showed that a certain increase in ETS exposure during the 4-year follow-up period occurred.

Doxycycline increases neurogenesis and reduces microglia in the adult hippocampus.

Adult hippocampal neurogenesis results in the continuous formation of new neurons and is a process of brain plasticity involved in learning and memory. Although inducible-reversible transgenic mouse models are increasingly being used to investigate adult neurogenesis, transgene control requires the administration of an activator, doxycycline (Dox), with unknown effects on adult neurogenesis. Here, we tested the effect of Dox administration on adult neurogenesis in vivo. We found that 4 weeks of Dox treatment at doses commonly used for gene expression control, resulted in increased neurogenesis. Furthermore, the dendrites of new neurons displayed increased spine density. Concomitantly, Iba1-expressing microglia was reduced by Dox treatment. These results indicate that Dox treatment may interfere with parameters of relevance for the use of inducible transgenic mice in studies of adult neurogenesis or brain inflammation.

Reconciling context and contact with immigrants effects: an examination of the Catalan case

Contact theory and threat group theory offer contradictory hypotheses regarding the effect of contact with immigrants. Despite recent efforts to test the validity of both approaches, we still lack a definitive conclusion. This article integrates both approaches and tests the effect of contact towards immigrants and how this changes when different contexts are considered. Mainly, we investigate the effect of the economic environment and the immigrant group size on modifying attitudes toward immigration. The hypotheses, which are tested in Catalonia, show that contact with immigrants reduce negative attitudes towards immigration, especially friendship and family contact. However, mixed results are reported regarding the effect of economic environment and immigrant group size. Whereas the former modifies positively the effect of workplace contact, the latter has no effect. Findings have implications for the impact of context when dealing with the impact of contact on attitudes towards immigration.

Terminaali, oma vai ulkoistettu

Insinöörityö tehtiin Panalpina Finland Oy:lle. Työn tarkoituksena oli selvittää, kumpi on yritykselle kustannustehokkaampi vaihtoehto, nykyinen, ulkoistettu terminaali vai investointi omaan terminaaliin. Ulkoistettu terminaalitila on käynyt yrityksen nykyiselle tavaramäärälle riittämättömäksi. Yrityksen ja palveluntuottajan välisessä tiedonkulussa sekä tavaran kierron hitaudessa esiintyy myös ongelmia. Näiden syiden vuoksi nykyinen toiminta ei vastaa kohdeyrityksen yleistä imagotasoa, ja siksi yritys harkitsee investointia omaan terminaaliin. Teoriaosan alussa kerrotaan yleistä ulkoistamisesta sekä terminaali- ja varastotiloista. Sen jälkeen käsitellään varastoinnin kustannuksia ja keskeisiä tunnuslukuja, toimintolaskentaa sekä tasapainotettua mittaristoa. Investointilaskelmista selostetaan nykyarvomenetelmä, jota käytetään tämän työn tutkimuksissa laskentamenetelmänä. Teoriaosan loppuosassa kerrotaan ulkoistetun terminaalin ja oman terminaalin hyödyistä ja haitoista. Työn empiirisessä osassa esitellään kohdeyritys ja palveluntuottaja sekä kerrotaan osapuolten yhteistyöstä ja ongelmista. Tässä osassa esitetään myös nykyarvomenetelmällä lasketut terminaalivaihtoehtojen kannattavuustulokset. Työn lopussa on pohdinta ja yhteenveto. Tämän työn tutkimustulokset ovat luottamukselliset, minkä takia niitä ei ole esitetty työn julkisessa osassa.

Kuljetus- ja maarakennusyrityksen ympäristöohjelma

Ympäristöohjelma on osa ympäristöjärjestelmää. Ympäristöohjelma sisältää käytännön toimenpiteet, joilla varmistetaan ympäristötavoitteiden saavuttaminen. Tavoitteiden saavuttamiseksi ympäristöohjelmaan määritetään myös tarvittavat vastuuhenkilöt, keinot, aikataulut, resurssit ja mittarit, joilla tavoitteita mitataan. Insinöörityön tarkoituksena oli laatia Esko Gustafsson Oy:lle ympäristöohjelma vuosille 2007 - 2009. Tavoitteena oli myös laatia käytännön ohjeistukset merkittävien ympäristönäkökohtien hallintaan. Työ aloitettiin tunnistamalla yrityksen toiminnat ja määrittelemällä toimintojen ympäristönäkökohdat. Tämän jälkeen arvioitiin yrityksen merkittävät ympäristönäkökohdat, joiden pohjalta ympäristöohjelma laadittiin. Työn tuloksena saatiin laadittua tehokas ympäristöohjelma. Ympäristöohjelma pystytään viemään läpi erittäin pienillä resursseilla. Jos ympäristöohjelman tavoitteet saadaan täytettyä, säästetään merkittävästi kustannuksissa.

Paga o cobra : estudi de la morositat en el món empresarial

El tema del nostre treball és la morositat, centrant‐nos en el estudi d’un cas real en la relació entre dues empreses, un client i un proveïdor, en el què el client va presentar signes de morositat, encara que en cap moment va deixar de pagar cap factura al client. En primer lloc, volem analitzar dades sobre la morositat, per saber com és desenvolupa un cas real d’una empresa amb problemes de morositat i quines son les conseqüències de la morositat, centrant‐nos en dues possibles vies: la via judicial, amb una denúncia a l’Administració Concursal, i la que passa per acudir a certes empreses que, en el límit de la llei, fan servir mètodes persuasius, cal dir que Aquest és un dels objectius fonamentals del treball, és a dir, intentar trobar algunes de les possibles solucions a la morositat, així com intentar detectar aquesta i veure si es pot identificar un morós tipus, cosa que trobaríem d’extrema importància.D’altra banda, com es lògic, volem aplicar els coneixements adquirits en aquests últims anys pel que fa al àmbit de la economia, tant en l’anàlisi de les dades com en els altres apartats del treball.

Government Spending and Re-election

Does additional government spending improve the electoral chances of incumbent political parties? This paper provides the first quasi-experimental evidence on this question. Our research design exploits discontinuities in federal funding to local governments in Brazil around several population cutoffs over the period 1982-1985. We find that extra fiscal transfers resulted in a 20% increase in local government spending per capita, and an increase of about 10 percentage points in the re-election probability of local incumbent parties. We also find positive effects of the government spending on education outcomes and earnings, which we interpret as indirect evidence of public service improvements. Together, our results provide evidence that electoral rewards encourage incumbents to spend part of additional revenues on public services valued by voters, a finding in line with agency models of electoral accountability.

Interbank Competition with Costly Screening

We analyse credit market equilibrium when banks screen loan applicants. When banks have a convex cost function of screening, a pure strategy equilibrium exists where banks optimally set interest rates at the same level as their competitors. This result complements Broecker s (1990) analysis, where he demonstrates that no pure strategy equilibrium exists when banks have zero screening costs. In our set up we show that interest rate on loans are largely independent of marginal costs, a feature consistent with the extant empirical evidence. In equilibrium, banks make positive profits in our model in spite of the threat of entry by inactive banks. Moreover, an increase in the number of active banks increases credit risk and so does not improve credit market effciency: this point has important regulatory implications. Finally, we extend our analysis to the case where banks have differing screening abilities.

Auditory motion affects visual biological motion processing.

The processing of biological motion is a critical, everyday task performed with remarkable efficiency by human sensory systems. Interest in this ability has focused to a large extent on biological motion processing in the visual modality (see, for example, Cutting, J. E., Moore, C., & Morrison, R. (1988). Masking the motions of human gait. Perception and Psychophysics, 44(4), 339-347). In naturalistic settings, however, it is often the case that biological motion is defined by input to more than one sensory modality. For this reason, here in a series of experiments we investigate behavioural correlates of multisensory, in particular audiovisual, integration in the processing of biological motion cues. More specifically, using a new psychophysical paradigm we investigate the effect of suprathreshold auditory motion on perceptions of visually defined biological motion. Unlike data from previous studies investigating audiovisual integration in linear motion processing [Meyer, G. F. & Wuerger, S. M. (2001). Cross-modal integration of auditory and visual motion signals. Neuroreport, 12(11), 2557-2560; Wuerger, S. M., Hofbauer, M., & Meyer, G. F. (2003). The integration of auditory and motion signals at threshold. Perception and Psychophysics, 65(8), 1188-1196; Alais, D. & Burr, D. (2004). No direction-specific bimodal facilitation for audiovisual motion detection. Cognitive Brain Research, 19, 185-194], we report the existence of direction-selective effects: relative to control (stationary) auditory conditions, auditory motion in the same direction as the visually defined biological motion target increased its detectability, whereas auditory motion in the opposite direction had the inverse effect. Our data suggest these effects do not arise through general shifts in visuo-spatial attention, but instead are a consequence of motion-sensitive, direction-tuned integration mechanisms that are, if not unique to biological visual motion, at least not common to all types of visual motion. Based on these data and evidence from neurophysiological and neuroimaging studies we discuss the neural mechanisms likely to underlie this effect.

FBXW7α attenuates inflammatory signalling by downregulating C/EBPδ and its target gene Tlr4.

Toll-like receptor 4 (Tlr4) has a pivotal role in innate immune responses, and the transcription factor CCAAT/enhancer binding protein delta (C/EBPδ, Cebpd) is a Tlr4-induced gene. Here we identify a positive feedback loop in which C/EBPδ activates Tlr4 gene expression in macrophages and tumour cells. In addition, we discovered a negative feedback loop whereby the tumour suppressor FBXW7α (FBW7, Cdc4), whose gene expression is inhibited by C/EBPδ, targets C/EBPδ for degradation when C/EBPδ is phosphorylated by GSK-3β. Consequently, FBXW7α suppresses Tlr4 expression and responses to the ligand lipopolysaccharide. FBXW7α depletion alone is sufficient to augment pro-inflammatory signalling in vivo. Moreover, as inflammatory pathways are known to modulate tumour biology, Cebpd null mammary tumours, which have reduced metastatic potential, show altered expression of inflammation-associated genes. Together, these findings reveal a role for C/EBPδ upstream of Tlr4 signalling and uncover a function for FBXW7α as an attenuator of inflammatory signalling.

Regulating financial conglomerates

We investigate the optimal regulation of financial conglomerates which combinea bank and a non-bank financial institution. The conglomerate s risk-taking incentivesdepend upon the level of market discipline it faces, which in turn isdetermined by the conglomerate s liability strucure. We examine optimal capitalrequirements for standalone institutions, for integrated financial conglomerates,and for financial conglomerates that are structured as holding companies.For a given risk profile, integrated conglomerates have a lower probability offailure than either their standalone or decentralised equivalent. However, whenrisk profiles are endogenously selected conglomeration may extend the reachof the deposit insurance safety net and hence provide incentives for increasedrisk-taking. As a result, integrated conglomerates may optimally attract highercapital requirements. In contrast, decentralised conglomerates are able to holdassets in the socially most efficient place. Their optimal capital requirementsencourage this. Hence, the practice of regulatory arbitrage , or of transferingassets from one balance sheet to another, is welfare-increasing. We discuss thepolicy implications of our finding in the context not only of the present debateon the regulation of financial conglomerates but also in the light of existingUS bank holding company regulation.