Simulated annealing techniques for joint transmitter-receiver design in a multiple user access MIMO-OFDM channel

In this paper we consider the problem of the joint design of multiple transmitters and receivers in a MIMe- eFDM scenario. We consider that both the transmitters and receivers have multiple antennas, configuring a Multi-Input-Multi-Output (MIMe) channel. Based on this structure, space diversity techniques can be used to separate the signals transmitted by different users. Concretely, the proposed approach consists in beamforming at both sides of the system, combined with the Orthogonal-Frequency-Division-Multiplexing (eFDM) modulation. The goal is the minimization of the total transmitted power subject to constraints related to the Quality of Service (QoS) for each user in terms of the Bit Error Rate (BER) and the maximum transmitted power for some terminals. By making use of this approach, the Multiple Access Interference (MAI) is minimized and the physical resources are exploited in an optimum way. The design is based on Simulated Annealing (SA), an heuristic technique able to find the optimum design in this non-convex problem and that can take into account all kind of constraints.Postprint (published version

Autotransfusión predepósito en artroplastia total de cadera como programa de ahorro de sangre alogénica

Las necesidades transfusionales en Cirugía Ortopédica y Traumatología son elevadas, condicionando un alto coste. Existen diferentes técnicas de ahorro de sangre alogénica siendo la autotransfusión predepósito sin duda el patrón oro en la actualidad. Realizamos un estudio retrospectivo con el objeto de valorar si las técnicas de ahorro de sangre y especialmente la autotransfusión predepósito disminuyen las necesidades de transfusión alogénica en cirugía ortopédica programada de cadera. El mayor inconveniente de la autotransfusión fue el alto coste-efectividad. El principal factor que ancarece la técnica es la gran cantidad de unidades donadas y no transfundidas, que genera un rendimiento bajo de la misma. La anemización preoperatoria y la sobretransfusión pueden ser evitadas de forma sencilla con claros criterios de transfusión poco liberales. La optimización del ahorro de sangre alogénica se puede establecer mediante un programa interdisciplinar e individualizado según el tipo de cirugía y las características del paciente como la hemoglobina basal y el sexo. La autotransfusión predepósito es adecuada en cirugía ortopédica programada de cadera por su efectividad en el ahorro de sangre alogénica, su buena tolerancia y por la inocuidad del proceso.Transfusion requirements in orthopaedic surgery are raised and therefore costs are high. There are different allogenic blood saving techniques but predeposit auto- transfusion is the gold-standard at present. We performed a retrospective study with the objective of valuing the requie- rement decreasement of allogenic transfusion in hip pro- gram orthopaedic surgery through blood saving methods, specially predeposit autologous transfusion. Autologous transfusion's great problem was the raised cost-effective- ness. The main reason for the price increase of techniques used is the high number of donned units and not transfused after surgery which you end up with a low productive met- hod. Anaemia pre-surgery and overtransfusion can easily be avoided with clear inclusion lines in blood saving programs and no liberal transfusion protocols. The best way to save allogenic blood in total hip arthroplasty can be established by means of an interdisciplinar program but individualized for specific tipe of surgery and for patient's characteristics like initial haemoglobin and sex. Predeposit autologous transfusion is adequate in hip program orthopaedic surgery because its effectiveness in allogenic blood saving, its good tolerance and it is a safe method

A robust maximin approach for MIMO communications with imperfect channel state information based on convex optimization

This paper considers a wireless communication system with multiple transmit and receive antennas, i.e., a multiple-input-multiple-output (MIMO) channel. The objective is to design the transmitter according to an imperfect channel estimate, where the errors are explicitly taken into account to obtain a robust design under the maximin or worst case philosophy. The robust transmission scheme is composed of an orthogonal space–time block code (OSTBC), whose outputs are transmitted through the eigenmodes of the channel estimate with an appropriate power allocation among them. At the receiver, the signal is detected assuming a perfect channel knowledge. The optimization problem corresponding to the design of the power allocation among the estimated eigenmodes, whose goal is the maximization of the signal-to-noise ratio (SNR), is transformed to a simple convex problem that can be easily solved. Different sources of errors are considered in the channel estimate, such as the Gaussian noise from the estimation process and the errors from the quantization of the channel estimate, among others. For the case of Gaussian noise, the robust power allocation admits a closed-form expression. Finally, the benefits of the proposed design are evaluated and compared with the pure OSTBC and nonrobust approaches.Postprint (published version

Flexible MIMO architectures: guidelines in the design of MIMO parameters

One of the multiple advantages of communicating through MIMO systems is their inherent ability to provide flexible configurations. Following this line of thought, in this paper we present a generic framework to study the degrees of freedom in the design of MIMQ communication systems (e.g.: code length, number of multiplexed streams, or receiver structure). Precisely, we focus our efforts to bridge the gap between the design of MIMO systems with full and no channel state information at the transmitter side and also with different complexiry degrees at ihe receiver side. For instance, we can establish a trade-off, not only between the achievable rates and the diversity or beamforming gains, but also between the rate and the robustness to uncertainties in the channel state information.Postprint (published version

Mesozoic palaeogeographic evolution of the External Zones of the Betic Cordillera

14 páginas, 8 figuras.The main events characterizing the Mesozoic palaeogeographic evolution of the External Zones of the Betic Cordillera are outlined. The Triassic sediments show a 'germanic' type lacies over the entire region, ending with Late Triassic evaporites and variegated clays of Keuper facies. At the beginning of the Jurassic a transgression takes place, and a broad shallow-marine carbonate-platform environment appears. During the Carixian (180 Ma) the carbonate platform breaks down leading to the differentiation of two large palaeogeographic units: the Prebetic Zone where shallow-water environments prevailed throughout the Mesozoic, and the Subbetic Zone where the sediments are clearly pelagic. Within the Prebetic Zone, two palaeogeographic realms are differentiated: the External Prebetic ,showing important stratigraphic gaps in the Jurassic and Early Cretaceous sequence, and the Internal Prebetic with a thicker and more continuous stratigraphic sequence. Between the Prebetic and Subbetic Zones, a palaeogeographic realm is distinguished (Intermediate units) where turbiditic and pelagic materials were deposited. This zone corresponds approximately to a slope environment during most of Mesozoic times. In the Subbetic Zone a marked differential subsidence occurs during the Jurassic, leading to trough (Median Subbetic) and swells (External and Internal Subbetic). In the Median Subbetic, the deposits consist mainly of marls, pelagic limestones, radiolarites and calcareous turbidites, with mafic volcanic hand subvolcanic rocks. During the Cretaceous pelagic marls and marty limestones were laid down. Mesozoic sedimentation took place along the southern margin of the European plate, in an Atlantic-type continental margin underlain by continental crust. Three-dimensional schemes, explaining the main palaeogcographic events are included.Peer reviewe

Evaluating Functional Connectivity Alterations in Autism Spectrum Disorder Using Network-Based Statistics

[EN] The study of resting-state functional brain networks is a powerful tool to understand the neurological bases of a variety of disorders such as Autism Spectrum Disorder (ASD). In this work, we have studied the differences in functional brain connectivity between a group of 74 ASD subjects and a group of 82 typical-development (TD) subjects using functional magnetic resonance imaging (fMRI). We have used a network approach whereby the brain is divided into discrete regions or nodes that interact with each other through connections or edges. Functional brain networks were estimated using the Pearson's correlation coefficient and compared by means of the Network-Based Statistic (NBS) method. The obtained results reveal a combination of both overconnectivity and underconnectivity, with the presence of networks in which the connectivity levels differ significantly between ASD and TD groups. The alterations mainly affect the temporal and frontal lobe, as well as the limbic system, especially those regions related with social interaction and emotion management functions. These results are concordant with the clinical profile of the disorder and can contribute to the elucidation of its neurological basis, encouraging the development of new clinical approaches.A.D.-P. was supported by grant FPU13/01475 from the Spanish Ministerio de Educacion, Cultura y Deporte (MECD). This work was supported in part by the Spanish Ministerio de Economia y Competitividad (MINECO) and FEDER funds under grant BFU2015-64380-C2-2-R.Pascual-Belda, A.; Díaz-Parra, A.; Moratal, D. (2018). Evaluating Functional Connectivity Alterations in Autism Spectrum Disorder Using Network-Based Statistics. Diagnostics. 8(3). https://doi.org/10.3390/diagnostics8030051S8

On providing mobility management in WOBANs: Integration with PMIPv6 and MIH

The Wireless-Optical Broadband Access Network (WOBAN) is a promising access architecture that combines the high performance of optical networks with the ubiquity and convenience of wireless technologies. This article proposes a network-based mobility framework that is specially tailored for WOBANs. The proposed architecture is based on Proxy Mobile IPv6 and IEEE 802.21 mobility management protocols, but it also defines a number of optimizations that enable the seamless handover of mobile nodes. In particular, the hierarchical architecture together with the broadcast-and-select nature of the optical part of the WOBAN are leveraged to: optimize the mobility of users with respect to the overall network resources, both at the wireless access and optical distribution parts, remove the overhead of IP-in-IP tunneling between the PMIPv6 entities, and perform an efficient bicasting during the handover process to minimize packet loss.The authors would like to acknowledge the support of the EU-funded MEDIEVAL (grant FP7-ICT-2009-5/258053), the CAM-funded Medianet project (under code S-2009/TIC-1468) and the MICINN research grant TIN2010-20136-C03.European Community's Seventh Framework ProgramPublicad

ACUTE RESPONSES TO 4 VS. 4 SMALL-SIDED GAMES IN FOOTBALL PLAYERS

The aim of this study was to examine acute physiological responses, physical fitness parameters and timemotion characteristics associated with a 4-a-side small-sided game in amateur level players. Sixteen male football players (age 23.9±4.2 years) completed one 4-a-side small sided game with the aim of maintaining ball possession as long as possible. The participants were monitored for external load and physiological parameters, and tested before and after for physical fitness assessment. A Student’s paired t-test was conducted to determine the differences in physical fitness assessment. A repeated measures analysis of variance (ANOVA), with Bonferroni post-hoc test, was used to determine the dynamics of physiological parameters in players, their RPE and time-motion characteristics of SSG. A significant difference was found in 20 m sprint time between before and after the SSG (Δ=+1.3%). No significant differences were found between bouts or recovery periods for THb and SmO2, nor between HR-related variables (ES=.005-.383). Compared to RPE in bout 1, greater values were observed in bouts 2, 3, and 4 (Δ=+5.3%, p=.008, ES=.40; Δ=+9.6%, p=.002, ES=.98; Δ=+15.1%, p=.000, ES=1.29; respectively). No significant differences were found between bouts for time-motion characteristics. The results demonstrated that RPE responses increased throughout bout periods, whereas the rest of physiological parameters were maintained over the entire protocol. Due to possible fatigue accumulation, physical fitness performance was impaired (sprint) and the external load was reduced over the course of the protocol

Análisis por técnicas morfológicas y secuenciación de ADN del polen atmosférico de la Comunidad de Madrid: estudios preliminares. Morphological analysis and DNA sequencing of atmospheric pollen in Madrid region: preliminary study

Hasta el momento, el estudio de las partículas biológicas en el aire que respiramos, se ha dirigido, principalmente, al conocimiento y control del polen y esporas, aeroalérgenos cuyo impacto en salud es bien conocido. Recientemente la comunidad científica ha sugerido que el aire es un ecosistema en sí mismo, que tendría su propia “aerobiota”, compuesta principalmente por virus, bacterias, esporas de hongos y polen. Para estudiar en conjunto toda esta biodiversidad en el aire urbano en la Comunidad de Madrid, surge el consorcio pluridisciplinar AIRBIOTA-CM, que integra a cinco grupos de investigación de áreas muy diferentes, que pretenden obtener una visión conjunta sobre la composición y dinámica de las partículas biológicas del aire, optimizando los sistemas de muestreo y análisis. Las propuestas más novedosas de las investigaciones iniciadas por este consorcio, son la utilización de técnicas innovadoras de génetica molecular como la secuenciación masiva aplicada en metagenómica (“Next Generation Sequencing”, NGS) y el uso de nuevas estrategias de captación, como el empleo de aeronaves no tripuladas, para muestrear a diferentes alturas y en localizaciones geográficas urbanas que a priori puedan tener una composición diferente de la biota y tengan una actividad humana relevante. El proyecto se inicia en otoño de 2014, y los resultados preliminares que presentamos son los obtenidos mediante el análisis morfológico tradicional y el análisis del ADN del polen de una misma muestra procedente de un captador Burkard. Estos resultados evidencian que los captadores tipo Hirst utilizados por las redes aerobiológicas pueden emplearse también en los estudios de metagenómica, y que los datos obtenidos mediante la aplicación de ambos métodos de análisis coinciden a grandes rasgos, lo que revela que esta nueva metodología constituye una buena aproximación y posible alternativa al análisis morfológico, aunque se necesitan más estudios comparativos para adaptar bien esta tecnología. So far, the study of the biological particles in the air we breathe has been mainly directed at knowing and controlling pollen and spores, aeroallergens with a well-known health impact., It has been recently suggested that the air is an ecosystem in itself, and that it probably has its own biota, which would be composed mainly of viruses, bacteria, fungal spores, and pollen. The main objective of the AIRBIOTA-CM project is to study this diverse set of biological particles present in the urban air in the Community of Madrid using a multidisciplinary, innovative and integrative approach. The project is collaboration between five research groups in very different fields, which aim is to get an overview on the composition and dynamics of biological particles in the air to optimize the methods of sampling and analysis. As a methodological innovation, there is an attempt to apply the breakthroughs in metagenomics to the study of bioaerosols. In addition, new collection strategies have been used, such as the use of unmanned aerial vehicles by designing or adapting new samplers for these vehicles, to sample at different altitudes and in urban geographic locations that might presumably have a different composition of the biota and relevant human activity. The project started in autumn 2014. The preliminary results presented here refer to the comparison of results obtained by means of traditional (light microscopy) and metagenomics methods on atmospheric pollen in the Community of Madrid. The data obtained by both analyses coincide broadly, revealing that the molecular methodology is a good and possible alternative approach to morphological analysis, although more comparative studies to adapt well this technology are needed