Critical analysis and extension of the Hirshfeld atoms in molecules

The computational approach to the Hirshfeld [Theor. Chim. Acta 44, 129 (1977)] atom in a molecule is critically investigated, and several difficulties are highlighted. It is shown that these difficulties are mitigated by an alternative, iterative version, of the Hirshfeld partitioning procedure. The iterative scheme ensures that the Hirshfeld definition represents a mathematically proper information entropy, allows the Hirshfeld approach to be used for charged molecules, eliminates arbitrariness in the choice of the promolecule, and increases the magnitudes of the charges. The resulting "Hirshfeld-I charges" correlate well with electrostatic potential derived atomic charges

Inversion Analytics: Análisis sobre rentabilidad de inversiones mediante VAN y TIR

Inversion Analytics es una herramienta para facilitar el análisis en inversiones que se planteen en pequeñas, medianas y grandes empresas, en el que se plasmará toda la información necesaria para determinar los valores que entran en juego en la inversión. La aplicación realiza esta función mediante el cálculo de VAN (Valor Actual Neto) y TIR (Tasa Interna de Rentabilidad) de una inversión determinada, a partir de la información introducida por el usuario y teniendo en cuenta los distintos métodos de amortización de la inversión inicial, así como los distintos enfoques o supuestos en el que clasificaremos el horizonte temporal de la misma.

La Inspiració de Van Gogh

La Inspiració de Van Gogh ofereix una reflexió entre les similituds i coincidències de dues societats (la societat de finals del sXIX, i la societat actual) separades pel temps, però unides per la necessitat de trobar una sortida a tanta incomprensió artística i social.

Critical thoughts on computing atom condensed Fukui functions

Different procedures to obtain atom condensed Fukui functions are described. It is shown how the resulting values may differ depending on the exact approach to atom condensed Fukui functions. The condensed Fukui function can be computed using either the fragment of molecular response approach or the response of molecular fragment approach. The two approaches are nonequivalent; only the latter approach corresponds in general with a population difference expression. The Mulliken approach does not depend on the approach taken but has some computational drawbacks. The different resulting expressions are tested for a wide set of molecules. In practice one must make seemingly arbitrary choices about how to compute condensed Fukui functions, which suggests questioning the role of these indicators in conceptual density-functional theory

Response to the letter to the editor by Dr van den Berg

Letters to the editor

A cartography of the Van der Waals territory

The distribution of distances from atoms of a particular element E to a probe atom X (oxygen in most cases), both bonded and intermolecular non-bonded contacts, has been analyzed. In general, the distribution is characterized by a maximum at short EX distances corresponding to chemical bonds, followed by a range of unpopulated distances the van der Waals gap and a second maximum at longer distances the van der Waals peak superimposed on a random distribution function that roughly follows a d3 dependence. The analysis of more than five million interatomic"non-bonded" distances has led to the proposal of a consistent set of van der Waals radii for most naturally occurring elements, and its applicability to other element pairs has been tested for a set of more than three million data, all of them compared to over one million bond distances.

Els virus van fer evolucionar el cervell

Un retrovirus va contribuir a incrementar les capacitats cognitives dels éssers humans. Va incidir sobre un gen que també està involucrat en algunes malalties mentals

Cap a on van els programes de garantia social

En el present estudi es descriu l'experiència de la implantació dels PGS en la comunitat de Castella-La Manxa, partint d'un marc conceptual en el que es descriuen les modalitats i característiques de programes. Es detallen les dades obtingudes mitjançant d'un estudi empíric que ofereix informació sobre els diferents agents (professorat, alumnes, famílies) que concurreixen en tals Programes de Garantía Social.

Ellis-Van Creveld Syndrome. Case report and literature review

Ellis-van Creveld syndrome is a genetic disorder that was first described by Richard Ellis and Simon van Creveld in 1940. The four principal characteristics are chondrodysplasia, polydactyly, ectodermal dysplasia and congenital heart defects. The orofacial manifestations include multiple gingivolabial musculofibrous fraenula, dental anomalies, hypodontia and malocclusion. The disease can be diagnosed at any age, even during pregnancy. The differentiation should be made between Jeune syndrome and other orofaciodigital syndromes

Ellis-Van Creveld Syndrome. Case report and literature review

Ellis-van Creveld syndrome is a genetic disorder that was first described by Richard Ellis and Simon van Creveld in 1940. The four principal characteristics are chondrodysplasia, polydactyly, ectodermal dysplasia and congenital heart defects. The orofacial manifestations include multiple gingivolabial musculofibrous fraenula, dental anomalies, hypodontia and malocclusion. The disease can be diagnosed at any age, even during pregnancy. The differentiation should be made between Jeune syndrome and other orofaciodigital syndromes

New biogeographical and morphological information on Physaloptera ngoci Le-Van-Hoa, 1961 (Nematoda: Physalopteridae) in South-east Asian rodents

During a study of the helminth fauna of 1,643 rodents trapped along the Mekong River (Thailand, LaoPeople"s Democratic Republic and Cambodia) in 2008-2011, the spirurid nematode Physaloptera ngoci Le-Van-Hoa,1961 was recovered with an overall prevalence of 2.8%. Based on the original description, it was identified in nine of 23 different Murinae host species and is here reported for the first time from these three countries. A scanning electron microscopy study provides additional morphological data.

DOMINIQUE VALÉRIAN (ed.) (Cyrille Aillet, Sophie Gilotte, AnnelieseNef, Christophe Picard, Jean-Pierre Van Staëvel, Élise Voguet):Islamisation et arabisation de l’Occident musulman médiéval (VIIe–XIIesiècle)

This book is the result of a one-year seminar series"Islam médiéval d"Occident (VIIe-XVe)", held at the Colegio de España in Paris in 2006-07 by the Association des doctorants en histoire des mondes musulmans médievaux (Diwan http://diwan.hypotheses.org), and a second volume focusing on Arabization is expected (p. 33). The contributors" experience, alongside their university and research backgrounds, have led to the publication of articles of an outstandingly high level throughout this book. This scholarly achievement is combined with a thought-provoking theoretical framework, where Arabization and Islamization give a common theme to the proceedings, which are developed in four parts.

Prehospital ticagrelor in ST-segment elevation myocardial infarction

Background:The direct-acting platelet P2Y receptor antagonist ticagrelor can reduce the incidence of major adverse cardiovascular events when administered at hospital admission to patients with ST-segment elevation myocardial infarction (STEMI). Whether prehospital administration of ticagrelor can improve coronary reperfusion and the clinical outcome is unknown. Methods: We conducted an international, multicenter, randomized, double-blind study involving 1862 patients with ongoing STEMI of less than 6 hours' duration, comparing prehospital (in the ambulance) versus in-hospital (in the catheterization laboratory) treatment with ticagrelor. The coprimary end points were the proportion of patients who did not have a 70% or greater resolution of ST-segment elevation before percutaneous coronary intervention (PCI) and the proportion of patients who did not have Thrombolysis in Myocardial Infarction flow grade 3 in the infarct-related artery at initial angiography. Secondary end points included the rates of major adverse cardiovascular events and definite stent thrombosis at 30 days. Results: The median time from randomization to angiography was 48 minutes, and the median time difference between the two treatment strategies was 31 minutes. The two coprimary end points did not differ significantly between the prehospital and in-hospital groups. The absence of ST-segment elevation resolution of 70% or greater after PCI (a secondary end point) was reported for 42.5% and 47.5% of the patients, respectively. The rates of major adverse cardiovascular events did not differ significantly between the two study groups. The rates of definite stent thrombosis were lower in the prehospital group than in the in-hospital group (0% vs. 0.8% in the first 24 hours; 0.2% vs. 1.2% at 30 days). Rates of major bleeding events were low and virtually identical in the two groups, regardless of the bleeding definition used

Els mamuts es van extingir per falta de diversitat genètica

Els mamuts han sigut els mamífers més grans que hi ha hagut a terra ferma, i han esdevingut una icona de la prehistòria. També són un paradigma de les extincions. Últimament, la possibilitat d'analitzar el genoma d'espècies extingides ha obert una nova porta per estudiar els mecanismes que porten a l'extinció. Un equip de recerca, internacional i multidisciplinari, ha analitzat i comparat el genoma de diversos mamut llanuts ( Mammuthus primigenius ). Segons l'estudi, publicat a Current Biology, la pèrdua de diversitat genètica va ser clau per a la seva extinció.