Forming first-ranked early-type galaxies through hierarchical dissipationless merging

We have developed a computationally competitive N-body model of a previrialized aggregation of galaxies in a flat LambdaCDM universe to assess the role of the multiple mergers that take place during the formation stage of such systems in the configuration of the remnants assembled at their centres. An analysis of a suite of 48 simulations of low-mass forming groups (of about 1E13 solar masses) demonstrates that the gravitational dynamics involved in their hierarchical collapse is capable of creating realistic first-ranked galaxies without the aid of dissipative processes. Our simulations indicate that the brightest group galaxies (BGGs) constitute a distinct population from other group members, sketching a scenario in which the assembly path of these objects is dictated largely by the formation of their host system. We detect significant differences in the distribution of Sersic indices and total magnitudes, as well as a luminosity gap between BGGs and the next brightest galaxy that is positively correlated with the total luminosity of the parent group. Such gaps arise from both the grow of BGGs at the expense of lesser companions and the decrease in the relevance of second-ranked objects in equal measure. This results in a dearth of intermediate-mass galaxies which explains the characteristic central dip detected in their luminosity functions in dynamically young galaxy aggregations. The fact that the basic global properties of our BGGs define a thin mass fundamental plane strikingly similar to that followed giant early-type galaxies in the local universe reinforces confidence in the results obtained.Comment: 25 pages, 14 figures, 3 tables. Accepted to MNRA

Counteracting effects of soil biota on emergence and growth of herbaceous plants

https://doi.org/10.5281/zenodo.7972878Background Plants condition the biotic composition of their rhizosphere. In turn, this plant legacy on the soil biota may affect the performance of plants recruiting in their vicinity. Unravelling how plant-soil legacies drive plant recruitment is key to understand vegetation dynamics and plant community assembly. Studies on the topic usually focus on the effects of soil microbiota as a whole, while the relative role of different guilds of soil organisms in the plant recruitment processes is not usually dissected. Aims Here, we used soils of Mediterranean woody plant species to test whether arbuscular mycorrhizal fungi (AMF) and small-size microbiota (< 50 µm) (MB) affect the germination success and growth of eight herbaceous plants. Results We documented a significant increase in seedling emergence probability when small-sized MB was present and no effect of AMF. In contrast, the aboveground plant biomass decreased with the presence of MB and increased with that of AMF. Interestingly, those plants growing in the absence of MB and in soils from woody plants associated with higher AMF richness developed higher aboveground biomass. Conclusion This study brings new evidence on how soil microbial communities can determine the performance of their associated herb community, and also, how the effects of different microbial guilds may change across the plant ontogeny. Given these results, the differential effect of soil microbial functional guilds should be considered to better understand plant soil legacies and feedbacks, potentially driving plant recruitment and community assembly.Universidad de Jaén/CBUAThe Spanish Ministerio de Economía y Competitividad (MEC) throughout COEXMED II project (CGL2015-69118-C2-1-P)University of Jaén through Acción 9 programme.Project LifeWatch-SUMHAL-WP5 (LWE2103014) (5.1.7

Estudio inmunohistoquímico del carcinoma epidermoide de labio

Objetivos: Determinar la sobreexpresión de las proteínas cerb- B2, p53, bcl-2, Ki67 y CD44varV6 y establecer su valor pronóstico en el carcinoma epidermoide de labio. Diseño del estudio: Estudio inmunohistoquímico de las proteínas p53, c-erb-B2, bcl-2, ki67 y CD44varV6 en 79 carcinomas epidermoides de labio diagnosticados y tratados a lo largo de un periodo de 20 años. Los datos obtenidos fueron sometidos a análisis estadístico uni y multivariante. Resultados: La inmunotinción fue positiva en el 75% de los casos para la proteína c-erb-B2, en el 70,6% para la proteína p 53, en el 3,8% para la proteína bcl-2 y en el 89,9% para la molécula de adhesión cd44varV6. La expresión proteica de ki67 osciló entre un mínimo de 0% y un máximo de 6,29%. Los factores inmunohistoquímicos analizados no presentaron valor pronóstico en el carcinoma epidermoide de labio, y solamente los pacientes afectados por este tipo de tumores que expresaban la molécula de adhesión CD44varV6 se asociaron de forma significativa con una mayor supervivencia mediante el análisis de Kaplan-Meier. Conclusiones: Las técnicas inmunohistoquímicas analizadas para el estudio anatomopatológico del carcinoma epidermoide de labio no deberían realizarse rutinariamente, dado su mayor coste y su menor utilidad en la práctica clínica diaria.Objectives: To determine the expression of the c-erb-B2, p53, bcl-2, Ki67 and CD44varV6 proteins, and to establish their prognostic value in epidermoid carcinoma of the lip. Study design: Immunohistochemical study of the c-erb-B2, p53, bcl-2, Ki67 and CD44varV6 proteins in 79 epidermoid carcinomas of the lip, diagnosed and treated over a period of 20 years. The data obtained were subjected to uni- and multi-variate statistical analyses. Results: Immunostaining was positive in 75% of cases for c-erb- B2 protein, in 70.6% for p53 protein, in 3.8% for bcl-2 protein and in 89.9% for adhesion molecule CD44varV6. Ki67 protein expression varied between a minimum of 0% and a maximum of 6.29%. Most immunohistochemical factors analyzed presented no prognostic value for epidermoid carcinoma of the lip. Only those patients affected by this type of tumor that expressed the adhesion molecule CD44varV6 were significantly associated with a greater survival calculated by means of Kaplan-Meier analysis. Conclusions: The immunohistochemical techniques analyzed for the anatomicopathological study of epidermoid carcinoma of the lip should not routinely be used due to their high cost and low utility in daily clinical practice

The structure and ecological function of the interactions between plants and arbuscular mycorrhizal fungi through multilayer networks

Arbuscular mycorrhizas are one of the most frequent mutualisms in terrestrial ecosystems. Although studies on plant mutualistic interaction networks suggest that they may leave their imprint on plant community structure and dynamics, this has not been explicitly assessed. Thus, in the context of plant-fungi interactions, studies explicitly linking plant-mycorrhizal fungi interaction networks with key ecological functions of plant communities, such as recruitment, are lacking. 2. In this study, we analyse, in two Mediterranean forest communities of southern Iberian Peninsula, how plant-arbuscular mycorrhizal fungi (AMF) networks modulate plant-plant recruitment interaction networks. We use a new approach integrating plant-AMF and plant recruitment networks into a single multilayer structure. We also develop a new metric (Interlayer Node Neighbourhood Integration, INNI) to explore the impact of a given node on the structure across layers. 3. The similarity of plant species in their AMF communities is positively related to the observed frequency of recruitment interactions in the field. Results reveal that properties of plant-AMF networks, such as plant degree and centrality, can explain about the properties of plant recruitment network, such as in-and out-degree (i.e. sapling bank and canopy service) and its modular structure. However, these relationships differed between the two forest communities. Finally, we identify particular AMF that contribute to integrate the neighbourhood of recruitment interactions between plants. 4. This multilayer network approach is useful to explore the role of plant-AMF interactions on recruitment, a key ecosystem function enhanced by fungi. Results provide evidence that the complex structure of plant-AMF interactions impacts functional and structurally plant-plant interactions, which in turn may potentiallyMinisterio de Ciencia e Innovación, Grant/ Award Number: CGL2015-69118- C2- 2- P and PGC2018-100966- B- I0

Unilateral submandibular gland aplasia with ipsilateral sublingual gland hypertrophy presenting as a neck mass

The congenital absence off the major salivary glands is a very infrequent disorder, in which several glands are usually involved at the same time. Sometimes this disorder can be associated with other developmental anomalies. The unilateral aplasia of the submandibular gland is an extremely rare finding with only 14 cases reported in the literature. Clinically, this kind of patients may complain of dryness of the mouth, difficulties in chewing and swallowing, severe periodontal disease or multiple caries, but usually they follow an asymptomatic course. Salivary gland aplasia can be diagnosed with a large variety off imaging techniques, which include computer tomography (CT), magnetic resonance imaging (MRR), ultrasonography (UUS), sialography, or scintigraphy. In this paper we report a case off a patient referred to our department with a long term and progressive growing neck mass, who has an unilateral submandibular gland aplasia associated to an ipsilateral hypertrophy off the sublingual gland. © Medicina Oral S. L

GRASP algorithms for the robust railway network design problem

This paper analyzes the solvability of a railway network design problem and its robust version. These problems are modeled as integer linear programming problems with binary variables, and their solutions provide topological railway networks maximizing the trip coverage in the presence of a competing mode, both assuming that the network works fine and that links can fail, respectively. Since these problems are computationally intractable for realistic sizes, GRASP heuristics are proposed for finding good feasible solutions. The results obtained in a computational experience indicate that our GRASP algorithms are suitable for railway network design problems. © 2011 Springer Science+Business Media, LLC.We would like to thank the Spanish Ministerio de Fomento under grant PT-2007-003, Ministerio de Ciencia y Educacion under grant MTM2009-14243, the Junta de Andalucia under grant P09-TEP-5022 for supporting this research, the FEDER funds of the European Union and TUSSAM (Seville, Spain). Special thanks are due to two anonymous referees for their valuable comments.García-Archilla, B.; Lozano, AJ.; Mesa, JA.; Perea Rojas Marcos, F. (2011). GRASP algorithms for the robust railway network design problem. Journal of Heuristics. 19(2):399-422. https://doi.org/10.1007/s10732-011-9185-zS399422192Baaj, M., Mahmassani, H.: An AI-based approach for transit route system planning and design. J. Adv. Transp. 25(2), 187–210 (1991)Cancela, H., Robledo, F., Rubino, G.: A grasp algorithm with tree based local search for designing a survivable wide area network backbone. J. Comput. Sci. Technol. 4(1), 52–58 (2004)Díaz, J.A., Luna, D., Luna, R.: A grasp heuristic for the manufacturing cell formation problem. TOP (2011). doi: 10.1007/s11750-010-0159-3Feo, T., Resende, M.: A probabilistic heuristic for a computationally difficult set covering problem. Oper. Res. Lett. 8, 67–71 (1989)Goossens, J., van Hoesel, C., Kroon, L.: A branch-and-cut approach for solving railway line-planning problems. Transp. Sci. 38, 379–393 (2004)Institute of Electrical and Electronics Engineers: IEEE Standard Computer Dictionary: A Compilation of IEEE Standard Computer Glossaries (1990)Laporte, G., Mesa, J., Perea, F.: A game theoretic framework for the robust railway transit network design problem. Transp. Res., Part B, Methodol. 44, 447–459 (2010)Laporte, G., Marín, A., Mesa, J., Perea, F.: Designing robust rapid transit networks with alternative routes. J. Adv. Transp. 45, 54–65 (2011)Marín, A., García-Ródenas, R.: Location of infrastructure in urban railway networks. Comput. Oper. Res. 36, 1461–1477 (2009)Marín, A., Jaramillo, P.: Urban rapid transit network design: accelerated Benders decomposition. Ann. Oper. Res. 169(1), 35–53 (2009)Marín, A., Mesa, J.A., Perea, F.: Integrating robust railway network design and line planning under failures. Lect. Notes Comput. Sci. 5868, 273–292 (2009)Mauttone, A., Urquhart, M.E.: A route set construction algorithm for the transit network design problem. Comput. Oper. Res. 36, 2440–2449 (2009)Murphey, R., Pardalos, P., Pitsoulis, L.: A GRASP for the multitarget multisensor tracking problem. In: Networks. Discrete Mathematics and Theoretical Computer Science Series, vol. 40, pp. 277–302. American Mathematical Society, Providence (1998)Nesmachnow, S., Cancela, H., Alba, E.: Evolutionary algorithms applied to reliable communication network design. Eng. Optim. 39(7), 831–855 (2007)Schöbel, A., Scholl, S.: Line planning with minimal transfers. In: 5th Workshop on Algorithmic Methods and Models for Optimization of Railways, Number 06901 in Dagstuhl Seminar Proceedings (2006

Plant Traits and Phylogeny Predict Soil Carbon and Nutrient Cycling in Mediterranean Mixed Forests

Soil functioning is closely linked to the interactions between biological communities with the physical environment. Yet, the impact of plant community attributes on metabolic processes promoting soil nutrient cycling remains largely unknown. We hypothesized that the plant community acts as a regulating agent of nutrient mobilization in soils according to the phylogenetic and morpho-functional traits of plant species of which it is composed. Rhizosphere soils were collected in autumn and spring under 32 tree and shrub species in two Mediterranean mixed forests (four plots in each) located in southern Spain, and nine soil enzymatic activities related to C, N and P mobilization were assessed. Phylogeny and morpho-functional traits of plant species were recorded and their imprint in soil enzymatic activities across forests was determined. The results showed a plant phylogenetic signal for N mobilization in both forests, while it varied across forests for non-labile C and P mobilization. The plant phylogenetic signals were primarily driven by lineages that diversified through the Miocene, about 25 Myr ago. In addition, leaf traits and plant’s mycorrhizal type explained soil enzymatic activities independently from phylogeny. C and P mobilization increased under ectomycorrhizal plants, whilst enhanced N mobilization did occur under arbuscular mycorrhizal ones. The plant community composition led to a different carbon and nutrient mobilization degree, which in turn was mediated by distinct microbial communities mirroring differentiated resource-acquisition strategies of plants. Our results highlight the role of plant traits and mycorrhizal interactions in modulating carbon and nutrient cycling in Mediterranean mixed forest soils.CRUE-CSIC Springer Natur