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Nowadays, cruciate ligament injuries have increased in incidence, since practicing a sport or physical activity has become a trend in current societies. Although this lifestyle generates multiple benefits, as a consequence, injury has also increased. Due to its nature and complexity, the ligaments of the knee are those that are most frequently affected, mainly the ACL (anterior cruciate ligament). This tissue reacts to overexertion or movements out of range, either caused by the exercise itself or caused by trauma caused by the practice of physical activity, causing various degrees of sprain. Whatever the etiology of these injuries, they will require a therapy indicated for each degree of injury. This therapy initially entails immobilization of the affected area and later; physical therapy will be required to a lesser or greater degree. Commonly, in the physiotherapy of these injuries, rehabilitation exercises are prescribed, where the physiotherapist asks a patient to use equipment with an estimated weight. However, the effectiveness of a generalized therapy in this way does not always give the expected results. This is related to the fact that these therapies are standardized and do not consider some factors such as the remaining muscle fibres that are not directly affected by the sprain, which does not mean that they should not be considered. Therefore, in the present work, a biomodel of a human knee has been developed and used to evaluate numerically how the ACL acts under an external load, when there are different degrees of injuries, caused by trauma. Four case studies were considered: Case 1 (control case) where the ACL is healthy, Case 2 where the ACL presents a 1st-degree sprain, Case 3 where the ACL presents a 2nd-degree sprain, and finally Case 4 where the ACL presents a 3rd-sprain grade. After performing the analyses, in the control case, it was found that it presents a balance between tensile and compressive stresses. While in the 4th case, the most critical tensile stress decreases while compression stresses increase. This shows that the ligament, having considerable damage, no longer works as it should and can eventually damage the collateral structures. It was found that, when there was a sprain, where the continuity of the ligament is compromised, a second torsional moment occurs in the ACL which causes the tissue fibres not to act according to their normal physiology or in a healthy state. The results obtained from the present study provide the possibility of predicting where the following injuries will occur by considering the von Mises failure criterion. Likewise, they will allow to improve the therapeutic procedures considering not only the injured structure but also the system as a whole.

Tumors, trauma and infections are the main reasons for subjecting a patient to a bone reconstruction made with the use of bone grafts or prosthetic elements, using for example components such as osteosynthesis plates, meshes and screws for their stabilization.This study focuses on the photoelastic analysis of a customized prosthesis of the jaw for a patient diagnosed with osteonecrosis. A resin model was manufactured as follows: DICOM files were processed in ScanIP software to obtain an STL file that was used to generate an antagonist model of the healthy section of the jaw using CATIA software, then, models were printed in Acrylonitrile Butadiene Styrene (ABS). Following the resin casting technique, the printed model of the jaw was used to construct a resin model, which is tested to determine its mechanical behavior.After carrying out the photoelastic analysis, it was found that the assembly process generates stress concentration zones. Here, the stress reaches a maximum value after the application of a bite force of 130.9 N in the premolars. In this study near the premolars, 3 stress concentration zones were identified and overlap of stress fields is reveled.The results show the importance of planning in the design and assembly process to obtain the best results in the reconstruction, reducing in this way the risk of a surgical reoperation due to problems of rupture or loosening of the prosthesis.

The modelling of biological structures has allowed great advances in Engineering, Biology, and Medicine. In turn, these advances are seen from the design of footwear and sports accessories, to the design of prostheses, accessories and rehabilitation treatments. The reproduction of the various tissues has gone through an important evolution thanks to the development of computer systems and programs. However, knowledge of the medical-biological and engineering areas continues to be required, and it involves a considerable investment of time and resources. The resulting biomodels still require great precision. The present work shows a methodology that allows to optimize computational resources and reduce elaboration time of biomodels. Through this methodology, it is possible to generate a biomodel of high biofidelity of a human knee. This biomodel is constituted by hard tissues (cortical and trabecular bones) and soft tissues (ligaments and meniscus) resulting in the modelling of the lower third of the femur, the tibial plateaus, the anterior cruciate ligament, posterior cruciate ligament, external lateral ligament, interior lateral ligaments, and the meniscus. With this model and methodology, it is possible to perform numerical analyses that will provide results very similar to those of real life. As, the methodology allows to assign the mechanical properties to each tissue and the anatomical structure.

The recirculation system of a BWR-5 has 20 jet pumps. They are submerged in water in the cylindrical annular zone of the reactor. Their main function is the development of a forcing flow through the nuclear core. It increases the power of the reactor compared with the one obtained by natural circulation. These components have an important safety function in the operation of the reactor. In accordance with document BWRVIP-41 R4, it was concluded that the vibration induced by cross flow over the jet pump assemblies is one of the degradation mechanisms of such pumps. In this paper, the vibration induced by the cross flow at a jet pump assembly BWR-5 was analyzed. A numerical approach was developed. The natural frequencies were obtained, considering the Fluid-Structure Interaction (FSI). The first natural frequency was 25.7 Hz. A Computational Fluid Dynamics (CFD) analysis was carried, in conjunction with the Power Spectral Density (PSD). A frequency of vortex generation of 0.48 Hz was obtained. A vortex generation analysis was carried out with the Q-criteria. The results showed that resonance conditions are unlikely. Therefore, the structural integrity of the jet pump assemblies is maintained.

This paper presents a three-dimensional design of a compliant mechanism as a transmission system for its application in a novel human sternum prosthesis. The proposed compliant mechanism design is able to generate a coordinated movement between ribs during the respiratory process in human beings. Finite Element Method (FEM) analysis was performed in order to describe maximum stress values from the deformed elements of the mechanism by applying input forces. FEM results show that the compliant mechanism movements are proper for sternum prosthesis application, also it was possible to prove that maximum stress values generated in the mechanism, did not exceed the yield point of the material. Finally, by performing a fatigue analysis of the mechanism, it was possible to determine the maximum number of cycles that it can resist. Obtained results will be used to develop a complete design of the compliant mechanism and the sternum prosthesis in a prototype solution.

El surgimiento de la investigación en odontología, como disciplina independiente de la medicina y otras áreas del campo de las Ciencias de la Salud, es relativamente reciente. Desafortunadamente en México la investigación no es la base de la formación profesional y únicamente instituciones públicas como la UNAM, el IPN o la UAM son las que fomentan la formación científica en la mayoría de las escuelas y facultades de odontología del país.

Low back pain is a serious health problem that affects a lot of people in productive age (Lopez-Hernandez in Analisis del Puesto de Trabajo de Policia para Investigar la Posible Etiologia Laboral del Sindrome Doloroso Lumbar, Propuesta de Control. Universidad Instituto Politecnico Nacional, p. 13, 2010 [1]). In this research is presented an antigravity rehabilitation device, which is designed to allow the intervertebral decompression and the antigravity muscles rehabilitation of the lumbar area. In addition, the main components of the equipment such as the base, the frame and the iron where the patient lays down, is studied through a computational program (finite element method) that is used for developing a static-structural analysis. Finally, the automation of the equipment is shown since the execution times and movements used to decompression of the intervertebral discs and/or the rehabilitation of the spine (Asghar-Norasteh in Low Back Pain. InTech, pp. 33–34, 2012 [2]).

In this paper, a methodology has been proposed to obtain the response spectrum of a nuclear building caused by underground detonations. For the problem at hand, a reinforced concrete building containing a boiling water reactor was postulated. It was constructed on a hard soil with a zero-period acceleration of 0.26 g. Its structural damping was 7%. The building is subjected to horizontal vibrations originated from a detonation of 15 tons of TNT, located at a distance of 2000 m from the nuclear power plant site. Initially, an analytical evaluation was carried out to obtain the horizontal vibrations. In a second step, a foundation soil model was developed with the finite element method in conjunction with an explicit approach. ANSYS® Autodyn® code was used. The response spectrum due to the underground detonation was developed with the data obtained. It was compared with the safe shutdown earthquake (SSE) response spectrum and the operating basis earthquake (OBE) response spectrum. The results show that the seismic response spectrums envelop the explosion response spectrum. A resonance did not develop. The horizontal velocity is below the limits established by the regulations considered in this paper. Under this condition, the postulated building is safe.

Nowadays, nuclear power plants can use a dry storage cask (DSC) for the spent nuclear fuel (NSF) on site. It is a reinforced concrete vessel, which has an internal stainless steel cylinder. Its main function is to provide a barrier against radiation, to cool down the spent fuel and to avoid nuclear fission through the internal metallic surface that contains the radioactive material. This vessel has been designed to withstand different conditions such as free fall, penetration, crushing and extreme temperatures. However, there is limited knowledge about the assessment of an aircraft impact on such vessels in the open literature. In this paper, the case of an oblique impact (45° impact angle with respect to the horizontal) of a light aircraft against a dry storage cask was considered. Its structural integrity was evaluated. The containers were considered to be located in an outdoor area. The evaluation was carried out with the commercial ANSYS® code.

The analysis of the distribution of stress in dental organs is a poorly studied area. That is why computational mechanobiological analysis at the tissue level using the finite element method is very useful to achieve a better understanding of the biomechanics and the behaviour of dental tissues in various pathologies. This knowledge will allow better diagnoses, customize treatment plans, and establish the basis for the development of better restoration materials. In the present work, through the use of high-fidelity biomodels, computational mechanobiological analyses were performed on four molar models affected with four different degrees of caries, which are subjected to masticatory forces. With the analyses performed, it is possible to observe that the masticatory forces that act on the enamel are not transmitted to the dentin and to the bone and periodontal ligament to protect the nerve, as it happens in a healthy dental organ. With the presence of decay, these forces are transmitted partly to the pulp. The reactions to the external loads on the dental organs depend on the advances of the carious lesion that they present, since the distribution of stresses is different in a healthy tooth.

The aim of the present work is to identify the reactions of the dental organs to the different forces that occur during chewing and the transcendence of the union and contact maintained by the dental tissues. The study used a lower first molar biomodel with a real morphology and morphometry and consisting of the three dental tissues (enamel, dentin, and pulp) each with its mechanical properties. In it, two simulations were carried out, as would the process of chewing a food. One of the simulations considers the contact between the enamel and the dentin, and the other does not take it into account. The results obtained differ significantly between the simulations that consider contact and those that do not, establishing the importance of taking this contact into account. In this way, the theories that establish horizontal and lateral occlusion forces are present during the functional chewing process which are viable to be correct. The case studies carried out present not only the reasons for the failure of enamel but also the failure of the restoration materials used. This reflection will allow the development of more adequate materials, mechanical design of prostheses, implants, and treatment.

In this paper, the Cumulative Usage Factor (CUF) of a High Pressure Core Cooling System (HPCS) reactor nozzle of a Boiling Water Reactor was calculated. This fatigue damage has been caused by the sudden injection of cold water into the reactor vessel through such nozzle. For this purpose, a three-dimensional analysis was carried out. Accordingly, a transient heat transfer analysis was developed. The temperature distribution was determined. With this information, the stress analysis was carried out. The safe end was restricted to move along its axial direction and the forging end was free to expand axially and radially. The resultant stress field established the magnitude of the alternative stresses. In the last step, a fatigue analysis was developed. The most critical point is the junction of the nozzle with the thermal sleeve. The fatigue performance was evaluated during a period of sixty years. It was assumed that 1.5 cycles per year will take place. The fatigue curves of ASME code section III were used. The results showed that the Cumulative Usage Factor (CUF) vary with the temperature injection, being 0.4090 when the water injected was 4.44°C and 0.3797 when the water temperature was 37.77°C. Both of them were estimated for a period of 60 years of operation. Therefore, damage is reduced as the temperature of the injected water increases. Besides, it is advisable to at least follow the recommendations of the NUREG ́s 1800 and 1801 [1, 2]. In this way, the aging of the nozzle is adequately managed.

There are few machines developed to produce wear on a prosthesis so they are basically to evaluate the behavior of the knee and hip. Most of this equipment are either prototypes or incomplete devices, this is because this machines do not reproduce the movements of the body. The investigation presented in this article, focuses the fundaments of biomechanics to design and manufacture a machine that allows wear at the ankle joint. So that, the use of tomography or magnetic resonances with combination with computational programs allows the generation of an ankle joint model. This was realized in order to obtain all geometries of a personalized model for an endoprosthesis design. Used as a base to develop a personalized machine able to simulate movements of this joint, which consist of 3° of freedom; flection-extension, inversion-eversion and abduction-adduction. Likewise, it permit the simulation of the body load during the motion process.

In the present work, the creation of a tridimensional electronic prosthesis which intends to replace the left hand’s phalanges of a patient who suffered severe burns and needed to undergo a partial amputation surgery was performed. Parting of a CT tomography composed of 539 images, the contour delimitation, and separation of each phalanx was carried out through the usage of computerized platforms, such as 3D Slicer and Scan IP. Both software allow the user to analyze every single image in three different planes (axial, sagittal and coronal) and segment the areas of interest, in this case, the index, middle, ring and little fingers’ phalanges. Subsequently, with the support of the platform SolidWorks©, each phalanx was detailed for its connection and posterior 3D printing, implementing an electronic mechanism capable of reproducing flexion-extension movements. The computerized final model was also submitted to mechanical force tests and force simulations based on the analysis of finite elements to ascertain the selected material’s and model’s resistance.

This paper presents the experimental tests that have been carried out using a new implant design for osteosynthesis as a solution for the treatment of human rib fractures. First, it is provided a description of the proposed novel design of the osteosynthesis implant. Subsequently, it is described the proposal to develop an experimental test in order to determine if due to the use of this osteosynthesis implant the repaired rib becomes more rigid as compared to a healthy one. To carry out the experimental test, TEMARI test bed was used at the Robotics and Mechatronics Laboratory LARM at the University of Cassino in Italy. The obtained results showed from biomechanical aspects, that the design of the implant is an appropriate one for its application in the medical sector without being necessary to make any modification on its design. In addition, obtained results also showed the structural behavior of both the osteosynthesis plate and the rib when they are subjected to loading conditions simulating the respiratory cycle in humans.

When it is about restorative dental materials, aesthetics is traditionally preferred. This has led to the selection of materials very visually similar to the enamel, but unfortunately, their mechanical properties are not similar. This often translates into disadvantages than advantages. In the present work, a comparison is made of the stresses that occur during dental occlusion (dental bit) in a healthy dental organ and those that are generated in a dental organ with a dental zirconium restoration. Numerical simulation was carried out by means of the Finite Element Method, in computational biomodels, from Cone-Beam Tomography, to obtain the stresses generated during dental occlusion. It was found that the normal and von Mises stresses generated are substantially greater in the molar with restoration compared to those produced in the healthy molar. In addition, the normal function of the enamel and dentin to disperse these stresses to prevent them from reaching the pulp is altered. Therefore, it is necessary to analyze the indiscriminate use of this restoration material and consider other aspects, in addition to aesthetics and biocompatibility for the choice of restorative materials such as biomechanical compatibility.

Biofuels represent an energy option to mitigate polluting gases. However, technical problems must be solved, one of them is to improve the combustion process. In this study, the geometry of a piston head for a diesel engine was redesigned. The objective was to improve the combustion process and reduce polluting emissions using biodiesel blends as the fuel. The methodology used was the mechanical engineering design process. A commercial piston (base piston) was selected as a reference model to assess the piston head’s redesign. Changes were applied to the profile of the piston head based on previous research and a new model was obtained. Both models were evaluated and analyzed using the finite element method, where the most relevant physical conditions were temperature and pressure. Numerical simulations in the base piston and the new piston redesign proposal presented similar behaviors and results. However, with the proposed piston, it was possible to reduce the effort and the material. The proposed piston profile presents adequate results and behaviors. In future, we suggest continuing conducting simulations and experimental tests to assess its performance.

Parkinson’s disease (PD) is the second most common chronic degenerative brain disorder in the world preceded by Alzheimer’s disease, affecting one in every hundred people over sixty worldwide. This research shows the evaluation of hydrolyzed collagen specimens that emulate the viscoelastic properties of brain tissue. Also, an electromechanical clamp-type device is proposed for data acquisition as well as a graphic interface that displays samples values.

Active and passive safety have played an essential role in solidifying ground transportation. However, safety-focused on children with some rare diseases is little attacked. This article shows the design of a diseased leg prototype into a crash test dummy Q3, the novelty of this work is based on the morphology and biocompatibility of the lower limbs, which principal characteristics of this prototype replicate the shape of a child with bone-degenerative diseases. In this work, it shows the essential features that a child dummy of this type must contain in order to generate a homologation and approval under the strictest passive safety standards used in the automotive industry. Results show the important kinematics parameters and CAD bones development necessary to conform a new numerical crash test dummy prototype.

This paper presents dynamic tests that are performed on swine ribs. TEMARI (TEsting MAchine for Artificial RIbs) machine has been modified in order to set up and adapt an osteosynthesis implant in a fractured swine rib under load conditions emulating the respiratory cycle in a human being. The method for analyzing innovative implants is work ed out as based on strain gauge arrangements on the swine rib under testing with data acquisition system MM01-350 USB of Micro-Measurements. The test results are discussed in terms of motion characteristics of the specimen as well as the forces of compression and reaction on it during each compression cycle.

In this paper, the stress analysis of the support structure (skirt) of a Boiling Water Reactor (BWR-5) vessel is presented. Three transient loading conditions, which take place during the life of the plant, were evaluated, in order to determine the structural integrity under fatigue loading. The concept of Cumulative Usage Fatigue (CUF) was used. The guidelines of the subsection NB and subsection NF of Section III of the ASME Code were taken into account in the evaluation in conjunction with the Finite Element Analyses (FEA). In addition, the environmental fatigue penalty factors (Fen) were also considered during the evaluation. The environmental conditions affected the integrity of the skirt. Besides, a perturbation in the stresses was observed due to the dynamic forces generated by the jet pumps, which increased the CUF in the skirt.

The knee is a diarthrodial joint or a wide mobility joint (or a wide mobility joint), which involves an extremely complex mechanical analysis. The knee possesses a great stability in complete extension to support the corporal weight, and has the necessary mobility to perform diverse daily activities (jump, gait, trot, run, among others) and efficiently orients the foot in relation to the irregularities of the ground. At present, a general understanding is possessed of the forces acting onto the bone structural components of the knee joint during daily activities. On the other hand, by applying Finite Element algorithms it is possible to numerically simulate the anatomic systems that constitute the human body. This algorithm has turned out to be an important tool to determine research behavior of the bone is not an organism, to determinate the behavior of bones from a mechanical point of view. Additionally, they are applied as a foundation for prosthesis design and numerical model generation to solve problems related to clinical conditions. For example, the degenerative osteoarthritis of the knee is a chronic degenerative disease that is active in persons between the ages of 50 to 60 years old and involves severe wear of the joint. This condition can be accelerated by multiple circumstances, the main one big effect of articulated overload (obesity, knee deformation, meniscus injuries, among others). In this paper we propose that a static structural analysis of the knee joint, which involves three phases of the human gait: normal support, contact (foot-ground) and balancing of the leg. The angular position parameters and the forces acting on the joint were obtained, and applied into the corresponding numerical analyses for each gait phase. The numerical analyses are based on the kinetic and kinematic studies of the knee, to determine the orientation and range of mobility of the joint. The numerical model of the knee joint was developed from a Computed Axial Tomography scan which would assure bio-fidelity in the numerical evaluation. Obtaining as results: the von Misses equivalent stress, the maximum and minimum principal stresses and the total displacement. It was determined by this research, that the knee capacity to support the loads in each step of the gait process and it helped to establish a data base for the design and development of joint knee prosthesis.

This work presents a new procedure to determine the density of bone tissue from collected data by means of computed axial tomography (CAT) and bone density correlations of cancellous and cortical tissue with their elastic properties which were obtained from structure reconstruction software to determine the apparent density of bone. The main objective is to determine the anisotropic elastic properties in swine femoral bones on two orthogonal directions to produce a most real behavior of bone FE-model. A TC Brilliance axial scanner (tomograph) was used to obtain the desired images, which were then processed in the Digital Imaging and Communication in Medicine format using different software packages, including Scan IPTM, Scan FE v3.1TM, and ANSYS vl2 TM. Five Duroc-Jersey type swine femur specimens were used for the analysis. These specimens are considered to be equivalent to human specimens of 50 to 55 years of age, since they have been used for eighteen months in experimental processes. The experimental procedure included the processing of 60 tomographic cuts, which allowed the determination of the zone where the density maximum and minimum values of the bone tissue seem to be located. The results obtained displayed the anisotropic elastic behavior for each bone specimen within a voxel unit of precision. The findings of this study could allow a significant advance in the development of customized endo-prostheses by determining the elastic properties of the bone and developing more accurate FE-models. This will contribute to the improvement of the performance of artificial implants as well as to increasing the service life of these prostheses.

At the present, the development of prostheses has been extremely wide and focused on restoring the patient to their daily activities. Nevertheless, not much has been done to restore the capability of playing musical instruments, perhaps due to the complexity and sensibility needed to perform certain movements. For example, the fingering movements on a guitar or a piano, are random and require of different amounts of force to be applied to the instrument. Furthermore, the playing of an instrument is accomplished by muscular memory. Nowadays, in order to emulate such movements, the application of robotically programmed prostheses has improved. Nevertheless, this is not a good option for musicians, as this solution do not offer the sensation of actually playing the instrument. One of the options to achieve the mentioned aim, would be the development of mechanical prostheses that apply myoelectric technology, however these devises do not possess sufficient sensibility to perform the movements needed to play an instrument. In this research, a mechanical design to be manufactured using 3D impression of a forearm prosthesis for a transradial amputated patient that is able to be used to play the guitar, is presented. The prosthesis is capable to provide the service for basic rehabilitation or train a recently amputated patient recently amputated. The proposed prosthesis was manufactured by the use of a plastic 3D impression machine using ABS-P400 strings. The prosthesis consists of two parts; the first one is the main socket that is attached to the forearm while the second part, that supports the nib guitar. The mechanical design of the prosthesis was based on data obtained by videometry of a musician developing the basic strum on a guitar. With these data was possible to define the basic strum technique, the movements that are involved (displacements, speed, acceleration, forces, etc.) and the joints involved in the strum of a guitar. The obtained results are very encouraging, since the prosthesis can be applied to restore the musician ability to perform the basic tasks to execute on his instrument, as well as, rehabilitation activities. This first proposal could be optimized to produce a final product with higher quality and with a wider area of applicability.

This paper presents a synthesis of a spherical parallel manipulator for a shoulder of a seven-degrees-of-freedom prosthetic human arm using a multi-objective optimization. Three design objectives are considered, namely the workspace, the dexterity, and the actuators torques. The parallel manipulator is modelled considering 13 design parameters in an optimization procedure. Due to the non-linearity of the design problem, genetic algorithms are implemented. The outcomes show that a suitable performance of the manipulator is achieved using the proposed optimization.

Acceleration and velocity of Au nanoparticles suspended in ethanol were evaluated by considering optical transmittance experiments as a function of time. The evolution of the third order nonlinear optical characteristics of the sample was examined by a two-wave mixing technique at 532 nm wavelength with nanosecond pulses. The dynamical position and the nonlinear optical properties of the studied nanogold showed a strong dependence on nanoparticle size; besides an exponential behavior due to intermolecular interactions was estimated. A time-resolved mechano-optical effect was experimentally observed by a nanosecond optical Kerr gate configuration. Atomic Force Microscopy studies in a dielectric thin film sample prepared with the nanoparticles by a sol–gel processing route were conducted to determine the nanoparticles size distribution. Micrographic analysis pointed out that the explored nanoparticles size is between 65 and 155 nm with an average size of 98 nm. Potential applications for developing mechano-optical operations capable to modulate optical signals dependent on time were contemplated.

Interferometric optical experiments for measuring changes in fringe irradiance patterns dependent on optical and mechanical responses associated to carbon nanotubes are reported. Thin solid films conformed by multiwall carbon nanotubes were prepared by an aerosol pyrolysis method. A Michelson optical interferometer with a highly stable 488 nm wavelength was employed for evaluating the studied sample. According to the interferometric results, the strain of the carbon nanotubes presented a nonlinear behavior resulting from applied multiaxial forces. On the other hand, for further investigating the effect of the variation of the mechanical properties and the optical characteristics of the tubes, nonlinear optical experiments were performed when the sample was exposed to a mechanical action. The third order nonlinear optical response was explored with the assistance of the second harmonic provided by a Nd:YAG laser system in a two-wave mixing configuration. Potential applications for mechano-optical modulation by nanosystems based on carbon nanotubes are contemplated.

Purpose To evaluate the strain fields and to calculate the modulus of elasticity and Poisson's ratio of trabecular bone of the 6 lumbar vertebrae of the porcine spine by a 2-dimensional digital image correlation (2D DIC). Methods This study was performed through a 2D DIC technique and the specimens were tested under compression. The resulting images were analyzed numerically by 2D DIC. Then, representative regions of interest were examined. The strain fields were determined and stress-strain curves were obtained. Results The full field measurement of the strain in the lumbar bone spine was evaluated and with this data, the Young's modulus and Poisson's ratio were determined. Conclusions This research highlights the potential applications of noninvasive acquisition techniques in biomechanical analysis. This is useful in the mechanical characterization of bony structures and in the design of prostheses.

Título en ingles: Proceed to the innovation in the pharmaceutical industry. The case of Spain.Resumen: El presente artículo explora sectores que identifican la innovación en empresas farmacéuticas de España. Para ello se consideran firmas nacionales y filiales extranjeras establecidas en territorio nacional. El análisis realizado comprende el periodo de 2009 al 2011 para una población N=200 empresas afiliadas en ese momento a Farmaindustria y al Plan Profarma. El trabajo consistió en una búsqueda de información útil en las páginas web de las empresas farmacéuticas establecidas en España que pudieran describir de forma estática el perfil innovador del sector farmacéutico español a través del análisis estadístico descriptivo. De esta forma, se crea un cimiento para la documentación de los resultados en una base de datos con el propósito de obtener un panorama con determinación sobre el comportamiento del sector farmacéutico español, así como posibles tendencias.El alto contenido de aportación literaria sobre el sector farmacéutico, se expresa de forma globalizada a nivel nacional e internacional, desestimando datos e información que pudieran ofrecer señales de amenaza u oportunidad respecto al corto periodo de tiempo, ya que a su vez son equiparables a otros años puesto que la industria farmacéutica española se constituye por empresas de origen extranjero (50.5%) y de capital nacional (49.5%). De éstas últimas las pymes son las protagonistas de las pequeñas innovaciones de las firmas establecidas en Madrid y Barcelona principalmente.Abstract: This article explores sectors identified innovation in Spanish pharmaceutical companies. It also considers domestic firms and foreign subsidiaries in the country. The analysis covers the period 2009 to 2011 for a population N=200 affiliates at that time Farmaindustria and Plan Profarma. The work involved a search of useful information on the websites of pharmaceutical companies based in Spain statically describes the innovative profile of the Spanish pharmaceutical through descriptive statistical analysis. Thus a foundation for documenting the results in a database in order to get a picture with determination on the behavior of Spanish pharmaceutical sector and possible trends is created.The high content of literary contribution on the pharmaceutical sector is expressed in a globalized national and international level, rejecting data and information that could provide signals threat or opportunity regarding short period time, and which in turn are comparable to other years since the Spanish pharmaceutical industry is constituted by companies of foreign origin (50.5%) and domestic capital (49.5%). Of the latter SMEs are the protagonists of small innovations established in Madrid and Barcelona mainly.

Título en ingles: Mechanical design of an exoskeleton for upper limb rehabilitationTítulo corto: Diseño mecánico de un exoesqueletoResumen: El ritmo de vida actual, tanto sociocultural como tecnológico, ha desembocado en un aumento de enfermedades y padecimientos que afectan las capacidades físico-motrices de los individuos. Esto ha originado el desarrollo de prototipos para auxiliar al paciente a recuperar la movilidad y la fortaleza de las extremidades superiores afectadas. El presente trabajo aborda el diseño de una estructura mecánica de un exoesqueleto con 4 grados de libertad para miembro superior. La cual tiene como principales atributos la capacidad de ajustarse a la antropometría del paciente mexicano (longitud del brazo, extensión del antebrazo, condiciones geométricas de la espalda y altura del paciente). Se aplicó el método BLITZ QFD para obtener el diseño conceptual óptimo y establecer adecuadamente las condiciones de carga de servicio. Por lo que, se definieron 5 casos de estudio cuasi-estáticos e implantaron condiciones para rehabilitación de los pacientes. Asimismo, mediante el Método de Elemento Finito (MEF) se analizaron los esfuerzos y deformaciones a los que la estructura está sometida durante la aplicación de los agentes externos de servicio. Los resultados presentados en éste trabajo exhiben una nueva propuesta para la rehabilitación de pacientes con problemas de movilidad en miembro superior. Donde el equipo propuesto permite la rehabilitación del miembro superior apoyado en 4 grados de libertad (tres grados de libertad en el hombro y uno en el codo), el cual es adecuado para realizar terapias activas y pasivas. Asimismo, es un dispositivo que está al alcance de un mayor porcentaje de la población por su bajo costo y fácil desarrollo en la fabricación.Palabras clave: MEF, Blitz QFD, exoesqueletos, diseño mecánico.Abstract: The pace of modern life, both socio-cultural and technologically, has led to an increase of diseases and conditions that affect the physical-motor capabilities of persons. This increase has originated the development of prototypes to help patients to regain mobility and strength of the affected upper limb. This work, deals with the mechanical structure design of an exoskeleton with 4 degrees freedom for upper limb. Which has the capacity to adjust to the Mexican patient anthropometry (arm length, forearm extension, geometry conditions of the back and the patient’s height) BLITZ QFD method was applied to establish the conceptual design and loading service conditions on the structure. So, 5 quasi-static cases of study were defined and conditions for patient rehabilitation were subjected. Also by applying the finite element method the structure was analyzed due to service loading. The results presented in this work, show a new method for patient rehabilitation with mobility deficiencies in the upper limb. The proposed new design allows the rehabilitation of the upper limb under 4 degrees of freedom (tree degrees of freedom at shoulder and one at the elbow), which is perfect to perform active and passive therapy. Additionally, it is an equipment of low cost, which can be affordable to almost all the country population.Key words: FEM, Blitz QFD, exoskeletons, mechanical design.Recibido: agosto 20 de 2014 Aprobado: marzo 26 de 2015

The structural integrity of a BWR nuclear power plant can be compromised due to severe dynamic loads. Acoustic loads coming from a Safety Relief Valve branch can be adversely amplified if the steam flow is increased at the Main Steam Piping. This phenomenon has been reported previously in one BWR nuclear power plant. Its steam dryer was fractured and loose parts were generated due to high-cycle fatigue. This event has driven the United States Nuclear Regulatory Commission to issue specific regulations to evaluate acoustic loads which would be detrimental to the BWR steam dryer. In this paper, the acoustic loads were simulated when the steam flow is incremented from normal operation conditions to an Extended Power Uprate condition. It was analyzed, when the output power was incremented 14% and 28%. The initial conditions were determined with Computational Fluid Dynamics under steady state condition. This data was used in subsequent transient analysis. The model of Large Eddy Simulation was used and the acoustic simulation was performed with the Fowcs Williams and Hawkings Method. The Power Spectral Density was obtained with Fast Fourier Transform. The frequency peaks were found between 148 Hz and 155 Hz. These results are consistent with those obtained with the Helmholtz model and other results reported in the open literature. The results show that the peak pressure can be increased up to six times in resonance conditions, corresponding to a power uprate of 28%.