Comparison between the Performance of Algorithmic Optical Codes and Orthogonal Optical Codes in OCDMA Systems

A novel method to be used in OCDMA systems is exhaustively described in this paper. It uses Algorithmic Optical Codes (AOCs). They are based on the signature sequence idea. However patterns are constantly changing. A common seed for pseudo-random sequence is the signature element. In this paper a derivation of the probability of error due to the multiple-access interference is provided. An other contribution of this work is also the comparison between the AOCs and the Orthogonal Optical Codes (OOCs) with (auto- and cross-) correlation equal to one. Attending to the cardinality limitation problem observed in OOCs, the comparison is focused on the number of users allowed by the two different systems aforementioned. As result we state that a system using AOCs allows more users than one using OOCs when the codes are long enough

LED Jitter-Induced Limitation Effects in the Baud Rate of VLC

In this paper we show that the effect of jitter due to driver and LED is the limiting factor in the baud rate in L-PPM formats for VLC systems

Wireless Sensor Network based on OCDMA for closed environments

An infrared optical wireless system is presented, consisting on autonomous remote nodes communicating with a central node. The network is designed for telecommand/telemetry purposes, comprising a large number of nodes at a low data rate. Simultaneous access is granted by using CDMA techniques, and an appropriate selection of the code family can also keep power consumption to a minimu

Incidencia de lesiones cervicales asociadas a fracturas mandibulares aisladas causadas por agresión física

ResumenLos traumatismos suprclaviculares que se asocian a las fracturas de la mandíbula pueden ser generadores de lesiones cervicales, si estas no son diagnosticadas en la evaluación integral del paciente policontundido pueden pasar desapercibidas causando complicaciones neurológicas, musculares o la muerte.ObjetivoDeterminar la presentación e incidencia de las lesiones cervicales asociadas a las fracturas mandibulares.Material y métodosEstudio tipo cohorte, observacional, prospectivo-longitudinal, donde se incluyeron 25 pacientes con diagnóstico de fractura mandibular aislada durante el periodo de mayo de 2010 a febrero de 2011, que acudieron al servicio de cirugía maxilofacial del Hospital Central «Dr. Ignacio Morones Prieto» en San Luís Potosí.ResultadosDe los 25 pacientes, fueron 24 hombres y una mujer, con una edad media de 26,4 años. Los estudiantes fueron los más involucrados. El tipo de agresión física que destacó fue la violencia interpersonal por riña. El 44% de los pacientes identificó los efectos del uso de alcohol en sus agresores. Ninguno de los pacientes presentó alteraciones de sensibilidad y tuvieron una fuerza muscular normal. El tipo de lesión cervical predominante fue la anterolistesis. Radiográficamente, la dimensión de los tejidos blandos prevertebrales correspondió a las cifras promedio de los tejidos sanos, la inestabilidad cervical máxima fue de 3mm. El diámetro de la columna de aire, fue en promedio de C1:13,28mm, C3:11,52mm y C6:22,04mmConclusionesLas lesiones cervicales en pacientes con fractura mandibular causada por agresión física son comunes pero suelen cursar de manera subclínica por lo que es muy importante la inspección clínica y radiográfica.AbstractSupraclavicular trauma associated with fractures of the mandible may lead to cervical spine injuries if they are not diagnosed in the comprehensive evaluation of the multiple trauma patient, and may cause subclinical or unnoticed neurological and muscular complications, and even death.ObjectiveTo determine the presentation and incidence of cervical spine injuries associated with mandibular fractures.Material and methodsA prospective, longitudinal and observational study was performed on a 25 patient cohort diagnosed with isolated mandibular fracture during the period from May 2010 to February 2011, and who were seen in the “Dr. Ignacio Morones Prieto” hospital in San Luis Potosi (Mexico)ResultsThe majority of the 25 patients were students with a mean age of 26.4 years of whom 24 were male and 1 was female. The most frequent type of physical aggression was a violent interpersonal violence. The effects of alcohol on their assailants were identified by 44% of the patients. None of the patients showed any changes in sensitivity and had normal muscle strength. The type of cervical spine lesion was predominantly anterolisthesis. The prevertebral soft tissue was radiographically within normal limits and the, the dimension of the corresponded to the average figures for normal tissue, maximum cervical instability was 3mm. The mean diameters of the air column were, C1: 13.28mm, C3: 11.52mm, and C6: 22.04mm.ConclusionsCervical spine lesions in patients with mandibular fractures caused by physical assault are common and often have subclinical course, so a clinical and radiographic evaluation is very important

Enabling SCI-FI: service-oriented context-aware and intelligent future Internet

Internet is becoming a huge heterogeneous and dynamic network that is growing beyond its architectural limits. The scaling up of the number of communicating nodes and services is leading the Internet to an architectural crisis which in turn makes it difficult to provide services efficiently considering the requirements and context conditions of users. The Information-Centric Networking (ICN) approach proposes a network where the main paradigm is not an end-to-end communication between hosts, as in the current Internet. Instead, an increasing demand for efficient distribution of content has motivated the development of architectures that focus on information objects. ICN supports the proliferation of services and contents allowing seamless access to them. This work proposes a context-aware service negotiation protocol which will enable to find and compose services whilst meeting requesters’ requirements and, consequently, maximizing the QoE of users. We also provide the main details of a first implementation of the proposed service-oriented solution (SCI-FI) and discuss the gathered results.Postprint (published version

Opportunistic screening for atrial fibrillation versus detecting symptomatic patients aged 65 years and older: a cluster-controlled clinical trial.

Objective: The goal of this study was to assess the effectiveness of opportunistic screening through pulse palpation in the early detection of atrial fibrillation in subjects aged ≥ 65 years versus detection through an active search for patients with symptoms and/or complications and sequelae associated. -Material and methods: This was a cluster randomized controlled trial performed in 48 primary care centers of the Spanish National Healthcare System. A total of 368 physicians and nurses were randomized. The researchers in the Experimental Group (EG) performed opportunistic screening for auricular fibrillation, whereas the researchers in the Control Group (CG) actively searched for symptomatic patients. An ECG was performed on patients found to have an irregular heartbeat to confirm the diagnosis of auricular fibrillation. -Results: A total of 5,465 patients with a mean age of 75.61 were recruited for the EG, and 1,525 patients with a mean age of 74.07 were recruited for the CG. Of these, 58.6% were female, without significant differences between groups. Pulse was irregular in 4.3% and 15.0% of the patients in the EG and the CG, respectively (p<0.001). A total of 165 new cases of atrial fibrillation were detected (2.3%), 1.1% in the EG and 6.7% in the CG (adjusted OR: 0.29; 95%CI: 0.18-0.45). -Conclusions: Case finding for atrial fibrilation in patients aged ≥ 65 years with symptoms or signs suggestive of atrial fibrilation is a more effective strategy than opportunistic screening through pulse palpation in asymptomatic patients.pre-print325 K

Wireless Optical Communications for Intra-Spacecraft Networks Based on OCDMA with Random Optical Codes

In recent years, spacial agencies have shown a growing interest in optical wireless as an alternative to wired and radio-frequency communications. The use of these techniques for intra-spacecraft communications reduces the effect of take-off acceleration and vibrations on the systems by avoiding the need for rugged connectors and provides a significant mass reduction. Diffuse transmission also eases the design process as terminals can be placed almost anywhere without a tight planification to ensure the proper system behaviour. Previous studies have compared the performance of radio-frequency and infrared optical communications. In an intra-satellite environment optical techniques help reduce EMI related problems, and their main disadvantages - multipath dispersion and the need for line-of-sight - can be neglected due to the reduced cavity size. Channel studies demonstrate that the effect of the channel can be neglected in small environments if data bandwidth is lower than some hundreds of MHz

Teaching and Learning Physics with Smartphones

Innovación EducativaThe use of mobile technologies is reshaping how to teach and learn. In this paper the authors describe their research on the use of these technologies to teach physics. On the one hand they develop mobile applications to complement the traditional learning and to help students learn anytime and anywhere. The use of these applications has proved to have very positive influence on the students’ engagement. On the other hand, they use smartphones as measurement devices in physics experiments. This opens the possibility of designing and developing low cost laboratories where expensive material can be substituted by smartphones. The smartphones’ sensors are reliable and accurate enough to permit good measurements. However, as it is shown with some examples, special care must be taken here if one does not know how these apps used to access the sensors’ data are programmed

La PRL y la digitalización de la industria

La llegada de la Cuarta Revolución Industrial o Digitalización es una realidad. Las empresas persiguen una optimización de sus recursos añadiendo a las metodologías tradicionales como Lean Manufacturing los beneficios de la interconexión de los componentes de los sistemas productivos. Es precisamente esta interconexión y el trabajo relativamente autónomo de la maquinaria lo que, a la vez, elimina o reduce los riesgos clásicos de las industrias y hace que emerjan otros nuevos que afectarán al operario 4.0. No obstante, de igual forma que surgen nuevos riesgos, surgen también nuevas formas de abordarlos.The advent of Fourth Revolution or Digitization is already a reality. Companies follow the optimization of their resources adding to traditional tools, like Lean Manufacturing, the benefits from the interconnexion of all the parts that conform productive systems. This interconnexion and the autonomous work of machines eradicate classic labour accidents risks or, at least, reduce them, but also create new ones that worry Operator 4.0. However, in the same way this new paradigm contributes to create some new risks, it can offer new ways for dealing with them

Guidelines for Conservation and Restoration of Historic PolychromePlasterwork: the Church of St María la Blanca in Seville, Spain

Carrying out an intervention for the conservation and restoration of architectural heritage, focused on the preservation of decorative elements such as polychromed plasterwork, implies following a methodology to study the materials and techniques used in each case to establish an intervention proposal according to the circumstances. This work offers some methodological guidelines necessary to approach the conservation of plasterwork and its polychromies, applied in a recent case study according to the criteria established by the 14th General Assembly of ICOMOS in 2003, the Law 14/2007 of Andalusian Historical Heritage, the Law 16/1985 of the Spanish Historical Heritage, and indications contained in the ECCO Guidelines. The novelty of the paper is that it presents the conservation decisions on a real case from the beginning until the end — showing the entire process and validating the proposed methodology — by using current restoration techniques and digital tools for the reconstruction of plasterwork