A(e⃗,e′p⃗)(\vec{e},e'\vec{p})B responses: from bare nucleons to complex nuclei

We study the occurrence of factorization in polarized and unpolarized observables in coincidence quasi-elastic electron scattering. Starting with the relativistic distorted wave impulse approximation, we reformulate the effective momentum approximation and show that the latter leads to observables which factorize under some specific conditions. Within this framework, the role played by final state interactions and, in particular, by the spin-orbit term is explored. Connection with the nonrelativistic formalism is studied in depth. Numerical results are presented to illustrate the analytical derivations and to quantify the differences between factorized and unfactorized approaches.Comment: 26 pages, 5 figures. Improved and extended version. To be published in Phys. Rev.

Reaching the boundary between stellar kinematic groups and very wide binaries. IV. The widest Washington double star systems with rho > 1000 arcsec in Gaia DR3

Aims: With the latest Gaia DR3 data, we analyse the widest pairs in the Washington Double Star (WDS) catalogue with angular separations, $\rho$, greater than 1000 arcsec. Methods: We confirmed the pair's membership to stellar systems based on common proper motions, parallaxes, and (when available) radial velocities, together with the locii of the individual components in colour-magnitude diagrams. We also looked for additional closer companions to the ultrawide pairs, either reported by WDS or found by us with a new Gaia astrometric search. In addition, we determined masses for each star (and white dwarf) and, with the projected physical separation, computed the gravitational potential energy, |Ug*|, of the systems. Results: Of the 155159 pairs currently catalogued by WDS, there are 504 with $\rho$ > 1000 arcsec. Of these, only 2 ultrawide pairs have not been identified, 10 do not have any available astrometry, 339 have not passed a conservative filtering in proper motion or parallax, 59 are members of young stellar kinematic groups, associations or open clusters, and only 94 remain as bona fide ultrawide pairs in the galactic field. Accounting for the additional members at shorter separations identified in a complementary astrometric and bibliographic search, we found 79 new stars (39 reported, plus 40 not reported by WDS) in 94 ultrawide stellar systems. This sample is expanded when including new close binary candidates with large Gaia DR3 RUWE, $\sigma_{Vr}$, or a proper motion anomaly. Furthermore, the large fraction of subsystems and the non-hierarchical configurations of many wide systems with three or more stars is remarkable.Comment: Accepted to A&A. 38 Pages, 8 figures and 9 tables (4 tables online

Las bentonitas de la zona sur de Cabo de Gata (Almería). Geoquímica y Mineralogía

[ES] Se han estudiado las caracteristicas quimicas y mineralógicas de las bentonitas y esmectitas de esta region, asi como sus principales parametros cristalogdficos y fórmulas estructurales de las esmectitas.[EN] The chemical and mineralogical characteristics of bentonites and smectites of this region, as well as their main crystallographic parameters and structural formulae were studied. The bentonites are constituted by smectite (unique mineral present in the fine fraction), jarosite, zeolite and trydimite, as neoformed minerals, and by plagioclase, K feldspar, amphibole and mica as minerals inherited from parent materials. The values for crystallographic parameters of smectites and the variation range for structural cations are in accordance with those found by other authors for dioctahedral smectites.Peer reviewe

Bryozoans from Chella Bank (Seco de los Olivos), with the description 7 of a new species and some new records for the Mediterranean Sea

Chella Bank (also known as Seco de los Olivos seamount) is a volcanic submarine elevation (76–700 m deep) located ca. 16 km off the southern coast of Spain, within the Alboran Sea, in the Atlantic-Mediterranean transition zone. It represents a biodiversity hotspot for Europe, with more than 600 species listed to date, and contains several habitats included in the EU Habitats Directive. During three ship-based expeditions, several areas of Chella Bank were surveyed and sampled in a depth range of 95–729 m, resulting in new records that improve our knowledge on poorly studied phyla, such as bryozoans. In 14 of the 21 samples examined during this study, 43 bryozoan taxa could be identified. Among these, one species is described as new to science (Buskea medwaves sp. nov.) and three other ones are reported for the first time from the Mediterranean Sea, namely Terminoflustra barleei (Busk, 1860), Marguetta pulchra Jullien in Jullien & Calvet, 1903, and Schizomavella (Schizomavella) linearis profunda Harmelin & d’Hondt, 1992a. Some species were abundant in the samples, such as Adeonellopsis distoma (Busk, 1859), B. medwaves sp. nov., Entalophoroecia cf. deflexa, and Reteporella pelecanus López de la Cuadra & García-Gómez, 2001. The highest species richness was detected in rhodolith beds and on coral rubble bottoms (especially exposed above the sediments) compared with other bottom types and habitats such as sandy bottoms and muddy bottoms. The finding highlights the importance of these environments for bryozoans.En prens

INDICADORES DE SOSTENIBILIDAD EN AGROECOSISTEMAS HORTÍCOLAS EN CERRO PUNTA, CHIRIQUÍ, PANAMÁ

Cerro Punta is one of the main producing areas of fresh vegetables in Panama; responsible for the supply of more than 80% of these items in the country. Recently, a characterization of these productive systems was carried out, which reflected that agricultural activity is the main source of income for the community, but they are very dependent on the use of synthetic pesticides. The aim of this study was to evaluate the sustainability of horticultural agroecosystems in Cerro Punta, Chiriquí, Panama. For this, a K means cluster analysis was carried out in a preliminary manner, in which the cultivated area (ha) and the productive cost (USD per ha) were taken into consideration. Next, one farm per conglomerate was randomly selected and ten sustainability indicators were defined on a scale of 1-5, corresponding to the social (2), economic (4) and technical-environmental (4) dimensions; being required for a farm to be considered sustainable to achieve at least an average of 3 per dimension and the general sustainability index (ISG), must be 3 or superior. According to the results, only cluster 4 turned was sustainable, with an ISG of 3.9. However, the five types of farm turned out to be sustainable in the social dimension, due to the satisfaction of basic services. Yield improvements, crop diversification and other economic activities are required; in addition to promoting Integrated Pest Management. In conclusion, horticultural agroecosystems in Cerro Punta could be sustainable.Cerro Punta es una de las principales zonas productoras de hortalizas frescas en Panamá; responsable del abastecimiento de más del 80% de estos rubros en el país. Recientemente, se realizó una caracterización de dichos sistemas productivos, la cual reflejó que la actividad agrícola es la principal fuente de ingresos de la comunidad, pero dependen en gran medida del uso de plaguicidas de síntesis. El objetivo del presente estudio fue evaluar la sostenibilidad de los agroecosistemas hortícolas en Cerro Punta, Chiriquí, Panamá. Para ello, se realizó de manera preliminar, un análisis de conglomerado de K medias, en el cual se tomó en consideración el área cultivada (ha) y el costo productivo (USD por ha). Seguidamente, se seleccionó al azar una finca por conglomerado y se definieron, en una escala de 1 – 5, diez indicadores de sostenibilidad, correspondientes a las dimensiones social (2), económica (4) y técnico-ambiental (4); siendo requerido para que una finca se considere sostenible lograr como mínimo un promedio de 3 por dimensión y que el índice de sostenibilidad general (ISG), sea igual o mayor que 3. De acuerdo con los resultados, solamente el conglomerado 4 resultó ser sostenible, con ISG de 3.9. Sin embargo, los cinco tipos de finca resultaron ser sostenibles en la dimensión social, gracias a la satisfacción de servicios básicos. Se requieren mejoras en cuanto al rendimiento, la diversificación de cultivos y otras actividades económicas; además de fomentar el manejo integrado de plagas. En conclusión, los agroecosistemas hortícolas en Cerro Punta podrían ser sostenibles

Preparation of the catalyst support from the oil-shale processing by-product

5-methylresorcinol and the technical mixture of oil-shale phenolic compounds were applied for carbon aerogel preparation. Gels, which were prepared via base catalyzed polymerization were dried under supercritical conditions and subsequent pyrolysis of obtained dry aerogels led to carbon aerogels. Activation of carbon aerogel with CO2 and H2O was performed and porosity and the specific surface area of activated carbon aerogels were studied. Langmuir specific surface areas of well over 2000 m2/g were achieved and microporosity of carbon aerogel samples was tuneable ranging from below 50% until over 85%. Impregnation with the complex [Pd(C4HF6O)2] was carried out in supercritical CO2 using H2 for a quick reduction of Pd(II) to Pd(0). Eventually, highly porous material decorated with nanoparticles of black palladium was obtained having a homogeneous metal distribution