Effects of Using Immersive Media on the Effectiveness of Training to Prevent Ergonomics Risks.

In this work, the effects of using immersive media such as virtual reality on the performance of training programs to avoid ergonomics risks are analyzed. The advance of technology has made it possible to use low-cost portable devices able to generate highly immersive experiences in training programs. The effects of using this kind of device in training programs have been studied in several fields such as industrial security, medicine and surgery, rehabilitation, or construction. However, there is very little research on the effects of using immersive media in training workers to avoid ergonomics risk factors. In this study, we compare the effects of using traditional and immersive media in a training program to avoid three common ergonomics risk factors in industrial environments. Our results showed that using immersive media increases the participant's engagement during the training. In the same way, the learning contents are perceived as more interesting and useful and are better remembered over time, leading to an increased perception of the ergonomics risks among workers. However, we found that little training was finally transferred to the workplace three months after the training session.

Designing Cyclic Job Rotations to Reduce the Exposure to Ergonomics Risk Factors.

Job rotation is an administrative solution to prevent work-related musculoskeletal disorders that has become widespread. However, job rotation schedules development is a complex problem. This is due to the multi-factorial character of the disorders and to the productive and organizational constraints of the real working environments. To avoid these problems, this work presents an evolutionary algorithm to generate rotation schedules in which a set of workers rotate cyclically over a small number of jobs while reducing the potential for injury. The algorithm is able to generate rotation schedules that optimize multiple ergonomics criteria by clustering the tasks into rotation groups, selecting the workers for each group, and determining the sequence of rotation of the workers to minimize the effects of fatigue. The algorithm reduces prolonged exposure to risks related to musculoskeletal injuries and simplifies the assignment of workers to different tasks in each rotation. The presented procedure can be an effective tool for the design of job-rotation schedules that prevent work-related musculoskeletal disorders while simplifying scheduled changeovers at each rotation and facilitating job monitoring.

User-interfaces layout optimization using eye-tracking, mouse movements and genetic algorithms.

Establishing the best layout configuration for software-generated interfaces and control panels is a complex problem when they include many controls and indicators. Several methods have been developed for arranging the interface elements; however, the results are usually conceptual designs that must be manually adjusted to obtain layouts valid for real situations. Based on these considerations, in this work we propose a new automatized procedure to obtain optimal layouts for software-based interfaces. Eye-tracking and mouse-tracking data collected during the use of the interface is used to obtain the best configuration for its elements. The solutions are generated using a slicing-trees based genetic algorithm. This algorithm is able to obtain really applicable configurations that respect the geometrical restrictions of elements in the interface. Results show that this procedure increases effectiveness, efficiency and satisfaction of the users when they interact with the obtained interfaces.

Errors Using Observational Methods for Ergonomics Assessment in Real Practice.

OBJECTIVE: The degree in which practitioners use the observational methods for musculoskeletal disorder risks assessment correctly was evaluated. BACKGROUND: Ergonomics assessment is a key issue for the prevention and reduction of work-related musculoskeletal disorders in workplaces. Observational assessment methods appear to be better matched to the needs of practitioners than direct measurement methods, and for this reason, they are the most widely used techniques in real work situations. Despite the simplicity of observational methods, those responsible for assessing risks using these techniques should have some experience and know-how in order to be able to use them correctly. METHOD: We analyzed 442 risk assessments of actual jobs carried out by 290 professionals from 20 countries to determine their reliability. RESULTS: The results show that approximately 30% of the assessments performed by practitioners had errors. In 13% of the assessments, the errors were severe and completely invalidated the results of the evaluation. CONCLUSION: Despite the simplicity of observational method, approximately 1 out of 3 assessments conducted by practitioners in actual work situations do not adequately evaluate the level of potential musculoskeletal disorder risks. APPLICATION: This study reveals a problem that suggests greater effort is needed to ensure that practitioners possess better knowledge of the techniques used to assess work-related musculoskeletal disorder risks and that laws and regulations should be stricter as regards qualifications and skills required by professionals.

Using RGB-D sensors and evolutionary algorithms for the optimization of workstation layouts.

RGB-D sensors can collect postural data in an automatized way. However, the application of these devices in real work environments requires overcoming problems such as lack of accuracy or body parts' occlusion. This work presents the use of RGB-D sensors and genetic algorithms for the optimization of workstation layouts. RGB-D sensors are used to capture workers' movements when they reach objects on workbenches. Collected data are then used to optimize workstation layout by means of genetic algorithms considering multiple ergonomic criteria. Results show that typical drawbacks of using RGB-D sensors for body tracking are not a problem for this application, and that the combination with intelligent algorithms can automatize the layout design process. The procedure described can be used to automatically suggest new layouts when workers or processes of production change, to adapt layouts to specific workers based on their ways to do the tasks, or to obtain layouts simultaneously optimized for several production processes.

«El médico perfecto» de Morgagni y la calidad / Morgagni's «The perfect physician» and quality

No disponible

Influences on the use of observational methods by practitioners when identifying risk factors in physical work.

Most observational methods for musculoskeletal disorder risk assessment have been developed by researchers to be applied in specific situations, and practitioners could find difficulties in their use in real-work conditions. The main objective of this study was to identify the factors which have an influence on how useful the observational techniques are perceived to be by practitioners and to what extent these factors influence their perception. A survey was conducted on practitioners regarding the problems normally encountered when implementing these methods, as well as the perceived overall utility of these techniques. The results show that practitioners place particular importance on the support the methods provide in making decisions regarding changes in work systems and how applicable they are to different types of jobs. The results of this study can serve as guide to researchers for the development of new assessment techniques that are more useful and applicable in real-work situations.

Using Kinect™ sensor in observational methods for assessing postures at work.

This paper examines the potential use of Kinect™ range sensor in observational methods for assessing postural loads. Range sensors can detect the position of the joints at high sampling rates without attaching sensors or markers directly to the subject under study. First, a computerized OWAS ergonomic assessment system was implemented to permit the data acquisition from Kinect™ and data processing in order to identify the risk level of each recorded postures. Output data were compared with the results provided by human observers, and were used to determine the influence of the sensor view angle relative to the worker. The tests show high inter-method agreement in the classification of risk categories (Proportion agreement index = 0.89 κ = 0.83) when the tracked subject is facing the sensor. The camera's point of view relative to the position of the tracked subject significantly affects the correct classification of the postures. Although the results are promising, some aspects involved in the use of low-cost range sensors should be further studied for their use in real environments.

CF2 activity and enhancer integration are required for proper muscle gene expression in Drosophila.

The creation of the contractile apparatus in muscle involves the co-activation of a group of genes encoding muscle-specific proteins and the production of high levels of protein in a short period of time. We have studied the transcriptional control of six Drosophila muscle genes that have similar expression profiles and we have compared these mechanisms with those employed to control the distinct expression profiles of other Drosophila genes. The regulatory elements controlling the transcription of co-expressed muscle genes share an Upstream Regulatory Element and an Intronic Regulatory Element. Moreover, similar clusters of MEF2 and CF2 binding sites are present in these elements. Here, we demonstrate that CF2 depletion alters the relative expression of thin and thick filament components. We propose that the appropriate rapid gene expression responses during muscle formation and the maintenance of each muscle type is guaranteed in Drosophila by equivalent duplicate enhancer-like elements. This mechanism may be exceptional and restricted to muscle genes, reflecting the specific requirement to mediate rapid muscle responses. However, it may also be a more general mechanism to control the correct levels of gene expression during development in each cell type.

Jaagsiekte sheep retrovirus is not detected in human lung adenocarcinomas expressing antigens related to the Gag polyprotein of betaretroviruses.

A proportion of human lung adenocarcinomas (hLACs) express an antigen related to the major capsid protein (CA) of Jaagsiekte sheep retrovirus (JSRV), a Betaretrovirus that causes a transmissible lung cancer in sheep. In this study, we have investigated whether JSRV or related betaretroviruses are expressed in hLACs. Results obtained indicate that JSRV is not associated with human lung adenocarcinomas. However, a proportion of hLACs reacted positively in immunohistochemistry with antibodies specific towards different domains of the JSRV Gag suggesting that a bona fide retrovirus antigen could be expressed in these tumours. Further studies will be necessary to ascertain whether the detection of antigens cross-reacting with betaretrovirus Gag antisera in some hLACs is due to expression of a human endogenous retrovirus or, more unlikely, of an uncharacterized exogenous retrovirus.

Ceramide mediates TNF-alpha-induced insulin resistance on GLUT4 gene expression in brown adipocytes.

Tumour necrosis factor (TNF)-alpha impaired insulin induction on GLUT4 mRNA in foetal brown adipocytes, as demonstrated by quantitative RT-PCR and Northern blot. We have explored the hypothesis that some effects of TNF-alpha could be mediated by the generation of ceramide, since TNF-alpha treatment induced the production of ceramide in these primary cells. A short-chain ceramide analogue, C2-ceramide, precluded insulin-induced GLUT4 mRNA accumulation and GLUT4-chloramphenicol acetyltransferase (CAT) full promoter activation. Moreover, inhibition of the ceramide biosynthesis with fumonisin B, which inhibits ceramide synthase, completely restored insulin-induced GLUT4 mRNA and protein accumulation as well as GLUT4-CAT transactivation in the presence of TNF-alpha. In consequence, TNF-alpha-induced insulin resistance on glucose uptake was completely alleviated. In addition, TNF-alpha down-regulated insulin-induced CCAAT/enhancer binding protein (C/EBP)-alpha gene expression and DNA binding activity, but fumonisin B precludes these effects. Furthermore, co-transfection with a wild-type C/EBP-alpha construct transactivates GLUT4-CAT construct. Our results indicate that de novo ceramide produced by TNF-alpha-induced insulin resistance on GLUT4 gene expression in brown adipocytes by interfering C/EBP-alpha expression, a transcription factor essential for the expression of GLUT4.

Comparative analysis of the pathogenic mechanisms associated with the G8363A and A8296G mutations in the mitochondrial tRNA(Lys) gene.

Two mutations (G8363A and A8296G) in the mtDNA (mitochondrial DNA) tRNA(Lys) gene have been associated with severe mitochondrial diseases in a number of reports. Their functional significance, however, remains unknown. We have already shown that homoplasmic cybrids harbouring the A8296G mutation display normal oxidative phosphorylation, although the possibility of a subtle change in mitochondrial respiratory capacity remains an open issue. We have now investigated the pathogenic mechanism of another mutation in the tRNA(Lys) gene (G8363A) by repopulating an mtDNA-less human osteosarcoma cell line with mitochondria harbouring either this genetic variant alone or an unusual combination of the two mutations (A8296G+G8363A). Cybrids homoplasmic for the single G8363A or the A8296G+G8363A mutations have defective respiratory-chain enzyme activities and low oxygen consumption, indicating a severe impairment of the oxidative phosphorylation system. Generation of G8363A cybrids within a wild-type or the A8296G mtDNA genetic backgrounds resulted in an important alteration in the conformation of the tRNA(Lys), not affecting tRNA steady-state levels. Moreover, mutant cybrids have an important decrease in the proportion of amino-acylated tRNA(Lys) and, consequently, mitochondrial protein synthesis is greatly decreased. Our results demonstrate that the pathogenicity of the G8363A mutation is due to a change in the conformation of the tRNA that severely impairs aminoacylation in the absence of changes in tRNA stability. The only effect detected in the A8296G mutation is a moderate decrease in the aminoacylation capacity, which does not affect mitochondrial protein biosynthesis.

Two functionally identical modular enhancers in Drosophila troponin T gene establish the correct protein levels in different muscle types.

The control of muscle-specific expression is one of the principal mechanisms by which diversity is generated among muscle types. In an attempt to elucidate the regulatory mechanisms that control fiber diversity in any given muscle, we have focused our attention on the transcriptional regulation of the Drosophila Troponin T gene. Two, nonredundant, functionally identical, enhancer-like elements activate Troponin T transcription independently in all major muscles of the embryo and larvae as well as in adult somatic and visceral muscles. Here, we propose that the differential but concerted interaction of these two elements underlies the mechanism by which a particular muscle-type establish the correct levels of Troponin T expression, adapting these levels to their specific needs. This mechanism is not exclusive to the Troponin T gene, but is also relevant to the muscle-specific Troponin I gene. In conjunction with in vivo transgenic studies, an in silico analysis of the Troponin T enhancer-like sequences revealed that both these elements are organized in a modular manner. Extending this analysis to the Troponin I and Tropomyosin regulatory elements, the two other components of the muscle-regulatory complex, we have discovered a similar modular organization of phylogenetically conserved domains.

El microscopio del Padre Feijóo. En el preludio de la Patología de Morgagni / The Microscope of Father Feijóo. In the prelude of Morgagni's Pathology

Supe, leyendo a Marañón, del hecho anecdótico de que el Padre Feijóo, sabio español del XVIII, compró un microscopio y desencantado, tal vez porque esperaba más de él, decidió deshacerse del mismo enviándoselo a otra persona. Este hecho, aunque totalmente anecdótico, resulta paradójico en una persona de tan amplia cultura que además previamente había leído y escrito cosas interesantes sobre dicho invento. También paradójicamente, la Medicina de esa época, que había progresado mucho desde los tiempos del Renacimiento, ignoraba a la naciente Anatomía Patológica a pesar de sus crecientes avances, especialmente desde el siglo XVII. Este curioso paralelismo así como mi interés por todo lo relacionado con la microscopía me indujo a revisar la Historia de la Medicina de un momento en el que, confundida entre un caos de teorías, la Anatomía Patológica moderna preparaba su nacimiento oficial, lo que lograría con la publicación de la magna obra de Morgagni. Reviso también, aunque de forma panorámica la vida y la obra de Feijóo y el momento histórico que vivió, argumento sobre sus motivaciones por la microscopía así como sobre la posibilidad de que el modelo que compró fuera el del inglés Cuff. Finalmente transcribo íntegramente la carta, inédita hasta que Marañón la publicó, donde Feijóo describe y se deshace del microscopio (AU)

En el Sesquicentenario de Cajal: Averroes y el Sistema Nervioso / No disponible

El sesquicenteneario de Cajal nos invita a buscar en nuestra historia paralelismos que, guardando las diferencias y las distancias en el tiempo, bien merecen nuestra atención. Miramos en esta ocasión hacia Averroes (Ibn Rusd), siglo XII, cumbre de la filosofía medieval que desde su natal Córdoba musulmana habría de revisar los conocimientos médicos de la época analizándolos a través la filosofía de Aristóteles, quien estudiaba al hombre como una parte más de la naturaleza. Todo su sistema se sustentaba en un principio de bipolaridad que iniciándose en las cualidades elementales (caliente, húmedo, frío y seco) y combinándose entre sí constituirían los cuatro elementos (fuego, aire, agua y tierra) constitutivos a su vez de cuantas sustancias hay en la naturaleza y, por tanto, de tejidos y órganos. El sistema nervioso, en el concepto que de él tenemos hoy, ocuparía gran parte de su interés, y a pesar del carácter holístico de la medicina medieval, es posible deslindarlo del resto del organismo ya que el conjunto de sus funciones integrarían lo que Averroes denominaba facultad animal (funciones motoras, sensitivas y cognoscitivas) en oposición a la facultad nutritiva (funciones digestivas, respiratorias, reproductoras). Es ocasión también para reflexionar sobre como en otros momentos de la historia, en ausencia de microscopios y otros métodos de observación y análisis comunes hoy en día, el hombre se las ingenió para obtener provecho de los conocimientos de que disponía (AU)

The Cajal 150th anniversary invites us to look for parallelism in our history. Ibn Rusd, born in Moslem Córdoba (XIIth century) was a zenith in Medieval Philosophy and revised all medical knowledge of his time analyzing it through Aristotelian philosophy who considers man as a part of nature. This system was based on a principle of polarity that starts in the four elemental qualities (heat, wet, cold and dry) and by combining themselves constitutes the four elements (fire, air, water and earth) that compose all substances in nature, consequently tissues and organs. Despite holistic character of Medieval Medicine, nervous system, such as we see it today, can be easily considered apart since it constituted the so-called animal faculty (motor, sensitive and cognoscitive functions) in opposition to nutritive faculty (digestive, respiratory and reproductive functions) and Averroes devoted much attention to its understandig. This is also an occasion to think over how, other moments of the history, without counting on microscopes and other modern methods of observation and analysis, human being was able to obtain the best advantages of his knowledge (AU)

Evaluación de dispositivos automatizados para diagnóstico citológico en la prevención del cáncer de cérvix / Assessment of cytological automated devices in cervical cancer prevention

Antecedentes. La eficacia de las campañas de cribado para prevenir el cáncer de cérvix han demostrado su eficacia, especialmente en los paises desarrollados, donde su incidencia ha bajado notablemente. Planificar dichas campañas exige una infraestructura organizada en varios niveles, donde los servicios de Anatomía Patológica soportan la responsabilidad del diagnóstico. La comple-jidad del proceso mental que lleva a un diagnóstico citológico ha impedido hasta ahora el desarrollo de dispositivos automáticos que alivien la presión laboral que ejerce la enorme casuística generada y la rutinización. La moderna tecnología informática y de análisis de imágenes permiten hoy ya abor-dar este problema, tanto desde el punto de vista diagnóstico como para una estrategia de control de calidad en evitación de falsos negativos. Sobre estas bases nos proponemos evaluarla contribución que los dispositivos automáticos disponibles aportarían a la detección y control de calidad de las campañas de prevención del cáncer de cervix. Métodos. Revisión de la literatura. Resultados. En el momento de finalizar esta evaluación hemos detectado tres dispositivos cuya tecnología y grado de desarrollo difiere: AutoPap Primary Screening System (TriPath Imaging), ThinPrep Imaging System (Cytyc) e InPath (Molecular Diagnostics). Conclusiones. Los dispositivos automáticos de que se dispone actualmente se encuentran insuficientemente desarrollados (sólo AutoPap Imaging System cuenta con la aprobación de la FDA). Los recursos económicos y humanos deberían, al menos en el momento presente, dirigirse a fomentar institucionalmente el seguimiento de los programas de cri-bado y a apoyar organizativamente dichas campañas, más que a financiar equipos automáticos de diagnóstico. No obstante no debería dejarse de apoyar el desarrollo de estos dispositivos ya que, a medio plazo, con el previsible incremento de la población controlada y alcanzando un razonable equi-librio coste-eficacia, es muy probable que sea necesario apoyarse en esta tecnología. (AU)

The A8296G mtDNA mutation associated with several mitochondrial diseases does not cause mitochondrial dysfunction in cybrid cell lines.

Transmitochondrial cybrid cell lines homoplasmic for the A8296G mtDNA transition, a mutation associated with several mitochondrial diseases, have a normal oxidative phosphorylation function, as shown by oxygen consumption, lactate production, respiratory enzyme activities, and growth using galactose as the only source of energy. The synthesis of mitochondrial proteins is also similar in mutant and wild-type cybrids. Our results suggest that the A8296G mutation is a polymorphism and reinforce the necessity of performing functional studies to assess the pathogenicity of mtDNA mutations.