6,516 research outputs found
Exchange Rate Volatility and Economic Performance in Peru: A Firm Level Analysis
This paper analyzes the impact of the exchange rate volatility on the performance of the Peruvian economy using financial information from 163 non-financial listed firms. We find evidence that, for firms holding dollar-denominated debt, investment decisions are negatively affected by real exchange rate depreciation. The reasons behind this result are: (i) the high degree of liability dollarization and currency mismatch that create the conditions for a balance sheet effect and a financial stress in the aftermath of a currency depreciation, (ii) the strong bank-lending channel that follows and reinforces the balance sheet effect, (iii) the domestic demand shrinkage that affects severely the firms sales, and (iv) the relatively small and poorly diversified export sector.
Reduced kinetic mechanisms for modelling LPP combustiĂłn in gas turbines
Reduced kinetic mechanisms for modelling LPP combustiĂłn in gas turbine
Multi-agent simulations for emergency situations in an airport scenario
This paper presents a multi-agent framework using Net- Logo to simulate humanand collective behaviors during emergency evacuations. Emergency situationappears when an unexpected event occurs. In indoor emergency situation, evacuation plans defined by facility manager explain procedure and safety ways tofollow in an emergency situation. A critical and public scenario is an airportwhere there is an everyday transit of thousands of people. In this scenario theimportance is related with incidents statistics regarding overcrowding andcrushing in public buildings. Simulation has the objective of evaluating buildinglayouts considering several possible configurations. Agents could be based onreactive behavior like avoid danger or follow other agent, or in deliberative behaviorbased on BDI model. This tool provides decision support in a real emergencyscenario like an airport, analyzing alternative solutions to the evacuationprocess.Publicad
Hydrophobic Ligand Binding by Zn-α_2-glycoprotein, a Soluble Fat-depleting Factor Related to Major Histocompatibility Complex Proteins
Zn-alpha2-glycoprotein (ZAG) is a member of the major histocompatibility complex (MHC) class I family of proteins and is identical in amino acid sequence to a tumor-derived lipid-mobilizing factor associated with cachexia in cancer patients. ZAG is present in plasma and other body fluids, and its natural function, like leptin's, probably lies in lipid store homeostasis. X-ray crystallography has revealed an open groove between the helices of ZAG's alpha1 and alpha2 domains, containing an unidentified small ligand in a position similar to that of peptides in MHC proteins (Sanchez, L. M., Chirino, A. J., and Bjorkman, P. J. (1999) Science 283, 1914-1919). Here we show, using serum-derived and bacterial recombinant protein, that ZAG binds the fluorophore-tagged fatty acid 11-(dansylamino)undecanoic acid (DAUDA) and, by competition, natural fatty acids such as arachidonic, linolenic, eicosapentaenoic, and docosahexaenoic acids. Other MHC class I-related proteins (FcRn, HFE, HLA-Cw*0702) showed no such evidence of binding. Fluorescence and isothermal calorimetry analysis showed that ZAG binds DAUDA with Kd in the micromolar range, and differential scanning calorimetry showed that ligand binding increases the thermal stability of the protein. Addition of fatty acids to ZAG alters its intrinsic (tryptophan) fluorescence emission spectrum, providing a strong indication that ligand binds in the expected position close to a cluster of exposed tryptophan side chains in the groove. This study therefore shows that ZAG binds small hydrophobic ligands, that the natural ligand may be a polyunsaturated fatty acid, and provides a fluorescence-based method for investigating ZAG-ligand interactions
Decomposing generalized transport costs using index numbers: A geographical analysis of economic and infrastructure fundamentals
We use the economic theory approach to index numbers in order to improve the existing definitions and decompositions of generalized transport costs (GTCs), and thus to obtain a better understanding of their economic and infrastructure determinants. Using this approach we accurately measure the contribution made to reducing GTCs by the variation in operating costs and accessibility variables, and discuss to what extent transportation policy has been successful in reducing GTCs in terms of market competition and infrastructure investments. To implement the optimizing behaviour of transportation firms when choosing minimum cost itineraries, we compile a new economic database on road freight transportation at a highly detailed provincial level, which is then embedded into a GIS to show the digitalized road networks corresponding to five-year intervals between 1980 and 2007. Average GTCs weighted by trade flows have decreased by -16.3% in Spain, with infrastructure policy leading the way in providing notable accessibility improvements in terms of lower times and distances. The contribution of infrastructure is double that of economic cost, whose trends are mainly driven by technological and market determinants rather than by specific competition and regulatory policies promoted by the administrations. We find large territorial disparities in GTC levels and variations, but also significant clusters where the market and network effects on GTC reduction show relevant and diverse degrees of spatial association. We finally conclude that after three decades of active transportation policy aimed mainly at intensifying investment in road infrastructure, there has been a significant increase in territorial cohesion in terms of GTCs and their components.Generalized transport costs; Index number theory; Infrastructure; GIS; Territorial cohesion.
Effects of quark family nonuniversality in SU(3)_c X SU(4)_L X U(1)_x models
Flavour changing neutral currents arise in the extension of the standard model because anomaly cancellation among the
fermion families requires one generation of quarks to transform differently
from the other two under the gauge group. In the weak basis the distinction
between quark families is meaningless. However, in the mass eigenstates basis,
the Cabibbo-Kobayashi-Maskawa mixing matrix motivates us to classify
left-handed quarks in families. In this sense there are, in principle, three
different assignments of quark weak eigenstates into mass eigenstates. In this
work, by using measurements at the Z-pole, atomic parity violation data and
experimental input from neutral meson mixing, we examine two different models
without exotic electric charges based on the 3-4-1 symmetry, and address the
effects of quark family nonuniversality on the bounds on the mixing angle
between two of the neutral currents present in the models and on the mass
scales and of the new neutral gauge bosons predicted by the
theory. The heaviest family of quarks must transform differently in order to
keep lower bounds on and as low as possible without
violating experimental constraints.Comment: 27 pages, 10 tables, 2 figures. Equation (19) and typos corrected.
Matches version to appear in Phys. Rev.
Un nuevo Ăndice para caracterizar el estado de conservaciĂłn de las praderas de Posidonia oceanica (L.) Delile
Se presenta el Ăndice de alteraciĂłn, un Ăndice que sirve para caracterizar el estado de conservaciĂłn de las praderas de Posidonia
Nonlinear waves in a chain of magnetically coupled pendula
A motivation for the study of reduced models like one-dimensional systems in Solid State Physics is the complexity of the full problem. In recent years our group has studied theoretically, numerically and experimentally wave propagation in lattices of nonlinearly coupled oscillators. Here, we present the dynamics of magnetically coupled pendula lattices. These macroscopic systems can model the dynamical processes of matter or layered systems. We report the results obtained for harmonic wave propagation in these media, and the different regimes of mode conversion into higher harmonics strongly influenced by dispersion and discreteness, including the phenomenon of acoustic dilatation of the chain, as well as some results on the propagation of localized waves i.e., solitons and kinks.Generalitat Valenciana APOSTD/2017/042Umiversitat Politècnica de València PAID-01-14Ministerio de EconomĂa y Competitividad (MINECO), Spain FIS2015-65998-C2-2-PJunta de AndalucĂa 2017/FQM-28
Violencia doméstica y conducta suicida: relatos de mujeres sobre la violencia y sus efectos
La violencia domĂ©stica se ha asociado a las conductas suicidas en mujeres vĂctimas de esta situaciĂłn. Sin embargo, son limitados los estudios que dan cuenta de la dimensiĂłn subjetiva de ambos hechos. El objetivo del trabajo fue identificar situaciones de violencia domĂ©stica en mujeres adultas que han intentado suicidarse y el estado afectivo asociado a dicha violencia. Participaron veinte mujeres con intento de suicidio reciente. Se aplicĂł una entrevista semiestructurada a cada una. Los hallazgos se organizaron en los siguientes cĂłdigos: descripciones de los hechos de violencia domĂ©stica; relaciĂłn entre violencia sufrida y la tentativa suicida; deber de ayudar a otros a pesar de su estado emocional; violencia internalizada; aislamiento y vacĂo como emociones asociadas al suicidio y la violencia; el suicidio como soluciĂłn a la violencia domĂ©stica. Estas vivencias ante la violencia domĂ©stica se sustentan en valores familiares y de gĂ©nero compartidos de forma cultural que vulneran emocionalmente a las mujeres.
The domestic violence has been associated to suicide behavior in female victims. However, the
subjective dimension of this association has been slightly studied. The aim of this work was to
identify situations of domestic violence in adult female suicide attempters and the emotional
state associated to the violence. 20 female suicide attempters participated. A semi-structured
interview was applied to each participant. Findings were organized as follows: descriptions
of domestic violence; relation between violence and suicide attempt; duty of helping others
in family nevertheless her emotional state; internalized violence; isolation and emptiness
as the emotions associated with suicide and violence; suicide as solutions to domestic
violence. The association between suicide and domestic violence are sustained in family and
gender values and beliefs. Females may be emotionally damaged by these cultural values.ITESO, A.C
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