Freedom of choice: the leximax criterion in the infinite case

Preprint submitted to Elsevier ScienceEste DT se publicó en su forma final en Mathematical Social Sciences 49 (2005) 1 – 15, http://dx.doi.org/10.1016/j.mathsocsci.2004.04.003Many recent works have investigated the problem of extending a preference over a set of alternatives to its power set, in an attempt to provide a formal representation of the notion of freedom of choice. In general, results are limited to the finite case, which excludes, for instance, the case of economic environments. This paper deals with the possibility of extending those results to the context where the basic set of alternatives is the n-dimensional Euclidean space. We present an extension of the leximax criterion described by Bossert, Pattanaik and Xu (1994) to this more general framework.This research has been supported by Spanish Ministry of Education grants SEC2000-0838 (a) and SEC2003-08105 (a) from DGICYT, PGIDIT03PXC30003PN (b) from Xunta de Galicia and BEC2002-3780 (b), from DGICYT

Evaluation of WRF model configurations for dynamic downscaling of tropical cyclones activity over the North Atlantic basin for Lagrangian moisture tracking analysis in future climate

This study assessed five well-established physics suites of the Weather Research and Forecasting (WRF) model in operational forecasting systems in the North Atlantic (NATL) basin or from previous sensitive experiments for dynamic downscaling tropical cyclone (TC) activity. We performed long-term simulations for the 2020 TC season in the NATL and compared the WRF tracks against the HURDAT2 dataset from the US National Hurricane Center. Among the tested configurations, the analysis revealed that the Kain-Fritsch, Purdue Lin, BouLac and revised MM5 schemes for cumulus, microphysics, planetary boundary layer and surface layer, respectively (hereafter WT), outperformed all four others in terms of TC frequency, track density and intensity and showed good performance in the cyclone accumulated energy and TC landfalling locations. In addition, WT well-captured the spatial distribution of accumulated TC precipitation and moisture uptake patterns, although it overestimated the precipitation maxima. Likewise, it agreed on the relative moisture contribution from fixed moisture sources (i.e., Gulf of Mexico, Caribbean Sea, tropical NATL, and western NATL) in the NATL basin. Overall, this study highlighted the high potential of using the WT physics suite in WRF for downscaling TC activity over the NATL basin, which will be useful for TC Lagrangian moisture sources analysis in future climate.Agencia Estatal de Investigación | Ref. PID2021-122314OB-I00Xunta de Galicia | Ref. ED431C 2021/44Xunta de Galicia | Ref. ED481B-2023/016Xunta de Galicia | Ref. ED481D 2022/020Universidade de Vigo/CISU

The role of moisture transport for precipitation in the inter-annual and inter-daily fluctuations of the Arctic sea ice extension

By considering the moisture transport for precipitation (MTP) for a target region to be the moisture that arrives in this region from its major moisture sources and which then results in precipitation in that region, we explore (i) whether the MTP from the main moisture sources for the Arctic region is linked with inter-annual fluctuations in the extent of Arctic sea ice superimposed on its decline and (ii) the role of extreme MTP events in the inter-daily change in the Arctic sea ice extent (SIE) when extreme MTP simultaneously arrives from the four main moisture regions that supply it. The results suggest (1) that ice melting at the scale of inter-annual fluctuations against the trend is favoured by an increase in moisture transport in summer, autumn, and winter and a decrease in spring and, (2) on a daily basis, extreme humidity transport increases the formation of ice in winter and decreases it in spring, summer, and autumn; in these three seasons extreme humidity transport therefore contributes to Arctic sea ice melting. These patterns differ sharply from that linked to the decline on a long-range scale, especially in summer when the opposite trend applies, as ice melt is favoured by a decrease in moisture transport for this season at this scale.</p

A One-Step, Versatile Synthesis of Dibenzo [n.2.2] Macrobicyclic Compounds via a Conformation-Directed Macrocyclization Reaction

A series of dibenzo [n.2.2] bicyclic compounds (n = 2–20) were prepared in one step and good yields starting from dimethyl anthracene-9,10-dicarboxylate. Reduction of the aromatic diester using lithium/naphthalene led to a bis-enolate that was cyclized with a variety of bis-electrophiles. The ease of the cyclization is probably due to the puckered conformation of the intermediate formed after the first alkylation step, in which the newly introduced chain that will become the bridge portion occupies a pseudoaxial position, positioning the leaving group close to the enolate nucleophile in the macrocyclization stepThis work was supported by the Ministerio de Economía y Competitividad of Spain (CTQ2011-22436) and Xunta de Galicia (PGIDIT10-PXIB209113PR, 10PXIB209155PR, and 2007/085)S

Dy4, Dy5, and Ho2 Complexes of an N3O2 Aminophenol Donor: A Dy5-µ3-Peroxide Single Molecule Magnet

The reactivity of the new flexible potentially pentadentate N3O2 aminophenol ligand H4Lr (2,2 -((pyridine-2,6-diylbis(methylene))bis(azanediyl))diphenol) towards different dysprosium salts and holmium(III) nitrate was investigated. Accordingly, this reactivity seems to greatly depend on the metal ion and salt employed. In this way, the reaction of H4Lr with dysprosium(III) chloride in air leads to the oxo-bridged tetranuclear complex [Dy4(H2Lr)3(Cl)4(μ3-O)(EtOH)2(H2O)2]·2EtOH·H2O (1·2EtOH·H2O), while the same reaction just changing the chloride salt by the nitrate one renders the peroxo-bridged pentanuclear compound [Dy5(H2Lr)2(H2.5Lr)2(NO3)4(μ3-O2)2]·2H2O (2·2H2O), where both peroxo ligands seem to come from the fixation and reduction of atmospheric oxygen. However, if holmium(III) nitrate is used instead of dysprosium(III) nitrate, no evidence of a peroxide ligand is observed, and the dinuclear complex {[Ho2(H2Lr)(H3Lr)(NO3)2(H2O)2](NO3)} 2.5H2O (3·2.5H2O) is isolated. The three complexes were unequivocally characterized by X-ray diffraction techniques, and their magnetic properties were analyzed. Thus, while the Dy4 and Ho2 complexes do not show magnet-like behavior even in the presence of an external magnetic field, 2·2H2O is a single molecule magnet, with an Ueff barrier of 61.2 K (43.2 cm−1). This is the first homonuclear lanthanoid peroxide SMM, which also shows the highest barrier among the reported 4f/3d peroxide zero field SMMs to date.This research received no external funding. J.C.-V. Thanks Xunta de Galicia for his postdoctoral fellowship (ED481B-2022-068), and P.O.-M. thanks the Fundación Segundo Gil Dávila for her PhD grant.S

Assessing the increasing frequency of heat waves in cuba and contributing mechanisms

This study presents the first climatological analysis of heat waves in Cuba from 1951 to 2023. Here we define a heat wave as a period of at least three consecutive days in which the daily maximum and minimum temperatures exceed their respective calendar-day 99th percentile. Our analysis detected a total number of 393 heat waves (∼ 5.4 events per year over the three regions (western, central and eastern) during the study period, distributed ∼ 3.1 per year during the dry season (from November to April) and ∼ 2.3 per year during the rainy season (from May to October). The highest frequency was recorded in the western region of Cuba, albeit the eastern region is the hottest one. The analysis of the life cycle of the heat waves revealed that they are relatively short-lived, with a mean duration of ∼ 4.9 and ∼ 5.3 days in the dry and rainy seasons, respectively. Furthermore, we found a statistically significant ( p  < 0.05) upward trend in the frequency, intensity, spatial extent and annual number of days under such hot extremes. The Lagrangian heat analysis revealed a predominantly local origin of the sensible heating, followed by heat advected from upwind sources throughout the easterly winds. An assessment of the main physical mechanisms associated with these heat waves revealed that, in general, these hot extremes were exacerbated by the soil moisture deficit, high-pressure conditions and associated clear skies and increased solar radiation. Based on the Heat Wave Magnitude Index, we also presented the top 10 Cuban heat waves, which mainly occurred in the last decade, confirming the upward trend in the intensity of these extreme events. Overall, this study provides insights into the heat waves in Cuba and contributes to the development of physically plausible storylines to help decision-makers in implementing mitigation and adaptation strategies in the context of global warming.Xunta de Galicia | Ref. ED431F-2024/03Xunta de Galicia | Ref. ED431C2021/44Universidade de Vigo/CISUGXunta de Galicia | Ref. ED481B−2023/016Xunta de Galicia | Ref. ED481D 2022/020Xunta de Galicia | Ref. ED481D−2024/017Agencia Estatal de Investigación | Ref. RYC2021-034044-IFundação para a Ciência e a Tecnología | Ref. DRI/India/0098/202

New occurrence records of Eleutherodactylus syristes in Guerrero and Oaxaca, Mexico

AbstractThe Sierra Madre del Sur (SMS) of southern Mexico is known for its exceptionally high levels of amphibian endemism, but knowledge of species’ ranges in the region is incomplete. Here, we report new locality records for Eleutherodactylus syristes (Hoyt, 1965) from the states of Oaxaca and Guerrero. Previously, this species was known only from the Pacific slopes of the Sierra de Miahuatlán and Mixteca Alta in Oaxaca. These new occurrence records extend the known range of this species by approximately 335km from the type locality and increase the elevational range, indicating it is more widespread in the SMS. Eleutherodactylus syristes is currently listed as endangered by the IUCN based on its limited distribution and ongoing threats to its persistence

On the asymptotic behaviour of solutions to the fractional porous medium equation with variable density

We are concerned with the long time behaviour of solutions to the fractional porous medium equation with a variable spatial density. We prove that if the density decays slowly at infinity, then the solution approaches the Barenblatt-type solution of a proper singular fractional problem. If, on the contrary, the density decays rapidly at infinity, we show that the minimal solution multiplied by a suitable power of the time variable converges to the minimal solution of a certain fractional sublinear elliptic equation.Comment: To appear in DCDS-