212 research outputs found
Self-repair ability of evolved self-assembling systems in cellular automata
Self-repairing systems are those that are able to reconfigure themselves following disruptions to bring them back into a defined normal state. In this paper we explore the self-repair ability of some cellular automata-like systems, which differ from classical cellular automata by the introduction of a local diffusion process inspired by chemical signalling processes in biological development. The update rules in these systems are evolved using genetic programming to self-assemble towards a target pattern. In particular, we demonstrate that once the update rules have been evolved for self-assembly, many of those update rules also provide a self-repair ability without any additional evolutionary process aimed specifically at self-repair
Implications for paleomobility studies of the effects of quaternary volcanism on bioavailable strontium: A case test in North Patagonia (Argentina).
Isótopos de estroncio87Sr /86Sr) se utilizan como trazadores geoquímicos para estudios de paleomovilidad porque muestran patrones predecibles y estables en ecosistemas controlados principalmente por los regímenes geológicos subyacentes. Si bien la geología del lecho de roca es estable durante miles de años, los procesos geomorfológicos pueden influir en la87Sr /86Sr en ecosistemas sobre escalas de tiempo arqueológicamente relevantes. Entre estos procesos geomorfológicos, la deposición y reelaboración de sedimentos volcánicos en escalas de tiempo cuaternarias son poco estudiados, pero podrían ser un control importante de87Sr /86Variaciones de Sr en muchas regiones arqueológicas. La Patagonia Norte es una región arqueológica clave para abordar los movimientos animales y humanos, y un lugar ideal para probar la influencia del vulcanismo cuaternario en87Sr /86Variación Sr, ya que se encuentra a favor del viento de los principales centros volcánicos. En este estudio, nuestro objetivo es evaluar los principales controles ambientales y geológicos de biodisponibles87Sr /86Sr y para construir un isoscape de alta resolución utilizando un marco de regresión de aprendizaje automático para futuros estudios de paleomovilidad. Tomamos muestras de varias ubicaciones y analizamos diferentes tipos de muestras (N = 94). Las proporciones muestran un rango limitado de variación, que no está relacionado con la geología del lecho de roca. Más bien, biodisponible87Sr /86Las variaciones de Sr muestran un aumento progresivo hacia el este (lejos de los Andes), luego de las deposiciones de polvo y las variaciones de elevación (R2 = 0,71, RMSE = 0,00041). Sostenemos que esta tendencia se relaciona con la deposición y reelaboración de sedimentos volcánicos no radiogénicos por erosión eólica, fluvial y glacial durante el Cuaternario. Como la mayor parte de esta reelaboración de sedimentos se produjo durante los períodos glaciales, la biodisponibilidad actual87Sr /86Las variaciones de Sr en el área de estudio probablemente representan un promedio a largo plazo que varió poco durante el Holoceno. En consecuencia, nuestro isoscape proporciona una base sólida para los estudios de paleomovilidad del Holoceno en la Patagonia Norte y subraya la importancia de los procesos de volcanismo cuaternario para la interpretación.87Sr /86Datos de Sr en estudios de paleomovilidad en regiones volcánicas
Small-scale mobility fostering the interaction networks of Patagonia (Argentina) hunter-gatherers during the Late Holocene: Perspectives from strontium isotopes and exotic items
During the Late Holocene, hunter-gatherer interaction networks significantly grew in intensity and extension across Patagonia. Although this growth is evidenced by the increased flow of exotic items across the region, the mechanisms behind these strengthening social networks remain unclear. Since evidence suggests that some individuals might have performed long-distance trips, this article aims to address the potential relationship between these individuals and the flows of exotic items in North Patagonia. We analyzed 54 enamel teeth for strontium isotopes and reconstructed their probable mobility using mixed-effect models and isotope-based geographic assignments. We inferred population and individual mobility trends and compared them against the flow of exotic items built from a standardized compilation. Our results indicate that most individuals have isotopic composition compatible with residence within their burial and surrounding areas. However, a few individuals show isotopic composition incompatible with their burial areas, which suggests axes -from the burial location to the most likely isotope integration area- of extraordinary mobility. At the same time, the flows of exotic items overlap with these axes around the eastern sector of the study area suggesting that this location could have been a central point of convergence for people and items. We argue that small-scale socially driven mobility could have played a relevant role as a general mechanism of interaction that fostered and materialized Patagonian interaction networks during the Late Holocene
Pathological Features of Breast Cancer seen in Northwestern Tanzania: A Nine Years Retrospective Study.
Breast cancer is more common in Western Countries compared to African populations. However in African population, it appears that the disease tends to be more aggressive and occurring at a relatively young age at the time of presentation. The aim of this study was to describe the trend of Breast Cancer in Northwestern Tanzania. This was a retrospective study which involved all cases of breast cancer diagnosed histologically at Bugando Medical Center from 2002 to 2010. Histological results and slides were retrieved from the records in the Pathology department, clinical information and demographic data for patients were retrieved from surgical wards and department of medical records. Histology slides were re-evaluated for the histological type, grade (By modified Bloom-Richardson score), and presence of necrosis and skin involvement. Data was entered and analyzed by SPSS computer software version 15. There were 328 patients histologically confirmed to have breast cancer, the mean age at diagnosis was 48.7 years (+/- 13.1). About half of the patients (52.4%) were below 46 years of age, and this group of patients had significantly higher tendency for lymph node metastasis (p = 0.012). The tumor size ranged from 1 cm to 18 cm in diameter with average (mean) of 5.5 cm (+/- 2.5), and median size of 6 cm. Size of the tumor (above 6 cm in diameter) and presence of necrosis within the tumor was significantly associated with high rate of lymph node metastasis (p = 0.000). Of all patients, 64% were at clinical stage III (specifically IIIB) and 70.4% had lymph node metastasis at the time of diagnosis. Only 4.3% of the patients were in clinical stage I at the time of diagnosis. Majority of the patients had invasive ductal carcinoma (91.5%) followed by mucinous carcinoma (5.2%), Invasive lobular carcinoma (3%) and in situ ductal carcinoma (0.3%). In all patients, 185 (56.4%) had tumor with histological grade 3. Breast cancer in this region show a trend towards relative young age at diagnosis with advanced stage at diagnosis and high rate of lymph node metastasis. Poor Referral system, lack of screening programs and natural aggressive biological behavior of tumor may contribute to advanced disease at the time of diagnosis
Implications for paleomobility studies of the effects of quaternary volcanism on bioavailable strontium: a test case in North Patagonia (Argentina)
Strontium isotopes (⁸⁷Sr/⁸⁶Sr) are used as geochemical tracers for paleomobility studies because they display predictable and stable patterns in ecosystems primarily controlled by the underlying geological regimes. While bedrock geology is stable over thousands of years, geomorphological processes can influence the ⁸⁷Sr/⁸⁶Sr in ecosystems over archeologically relevant timescales. Among these geomorphological processes, the deposition and reworking of volcanic sediments over Quaternary timescales are little studied but could be an important control of ⁸⁷Sr/⁸⁶Sr variations in many archeological regions. North Patagonia is a key archeological region to address animal and human movements, and an ideal location to test the influence of Quaternary volcanism on ⁸⁷Sr/⁸⁶Sr variation as it is located downwind of major volcanic centers. In this study, we aim to assess the main environmental and geological controls of bioavailable ⁸⁷Sr/⁸⁶Sr and to build a high-resolution isoscape using a machine learning regression framework for forthcoming paleomobility studies. We sampled several locations and analyzed different types of samples (N = 94). The ratios show a limited range of variation, which is not related to the bedrock geology. Rather, bioavailable ⁸⁷Sr/⁸⁶Sr variations display a progressive increase going eastward (away from the Andes), following dust aerosol deposition and elevation variations (R² = 0.71, RMSE = 0.00041). We argue that this trend relates to the deposition and reworking of unradiogenic volcanic sediments by aeolian, fluvial and glacial erosion during the Quaternary. As most of this sediment reworking occurred during glacial periods, the current bioavailable ⁸⁷Sr/⁸⁶Sr variations across the study area likely represent a long-term average that varied little during the Holocene. Consequently, our isoscape provides a solid base for Holocene paleomobility studies in North Patagonia and underlines the importance of Quaternary volcanism processes for interpreting ⁸⁷Sr/⁸⁶Sr data in paleomobility studies in volcanic regions.Facultad de Ciencias Naturales y Muse
POEtic Tissue: An Integrated Architecture for Bio-inspired Hardware
It is clear to all, after a moments thought, that nature has much wemight be inspired by when designing our systems, for example: robustness, adaptability and complexity, to name a few. The implementation of bio-inspired systems in hardware has however been limited, and more often than not been more a matter of artistry than engineering. The reasons for this are many, but one of the main problems has always been the lack of a universal platform, and of a proper methodology for the implementation of such systems. The ideas presented in this paper are early results of a new research project, "Reconfigurable POEtic Tissue". The goal of the project is the development of a hardware platform capable of implementing systems inspired by all three major axes (phylogenesis, ontogenesis, and epigenesis) of bio-inspiration, in digital hardware
Using the social entrepreneurship approach to generate innovative and sustainable malaria diagnosis interventions in Tanzania: a case study
<p>Abstract</p> <p>Background</p> <p>There have been a number of interventions to date aimed at improving malaria diagnostic accuracy in sub-Saharan Africa. Yet, limited success is often reported for a number of reasons, especially in rural settings. This paper seeks to provide a framework for applied research aimed to improve malaria diagnosis using a combination of the established methods, participatory action research and social entrepreneurship.</p> <p>Methods</p> <p>This case study introduces the idea of using the social entrepreneurship approach (SEA) to create innovative and sustainable applied health research outcomes. The following key elements define the SEA: (1) identifying a locally relevant research topic and plan, (2) recognizing the importance of international multi-disciplinary teams and the incorporation of local knowledge, (3) engaging in a process of continuous innovation, adaptation and learning, (4) remaining motivated and determined to achieve sustainable long-term research outcomes and, (5) sharing and transferring ownership of the project with the international and local partner.</p> <p>Evaluation</p> <p>The SEA approach has a strong emphasis on innovation lead by local stakeholders. In this case, innovation resulted in a unique holistic research program aimed at understanding patient, laboratory and physician influences on accurate diagnosis of malaria. An evaluation of milestones for each SEA element revealed that the success of one element is intricately related to the success of other elements.</p> <p>Conclusions</p> <p>The SEA will provide an additional framework for researchers and local stakeholders that promotes innovation and adaptability. This approach will facilitate the development of new ideas, strategies and approaches to understand how health issues, such as malaria, affect vulnerable communities.</p
D6.6 Final report on the METIS 5G system concept and technology roadmap
This deliverable presents the METIS 5G system concept which was developed to fulfil the
requirements of the beyond-2020 connected information society and to extend today’s
wireless communication systems to include new usage scenarios.
The METIS 5G system concept consists of three generic 5G services and four main enablers.
The three generic 5G services are Extreme Mobile BroadBand (xMBB), Massive Machine-
Type Communications (mMTC), and Ultra-reliable Machine-Type Communication (uMTC).
The four main enablers are Lean System Control Plane (LSCP), Dynamic RAN, Localized
Contents and Traffic Flows, and Spectrum Toolbox.
An overview of the METIS 5G architecture is given, as well as spectrum requirements and
considerations.
System-level evaluation of the METIS 5G system concept has been conducted, and we conclude that the METIS technical objectives are met.
A technology roadmap outlining further 5G development, including a timeline and recommended future work is given.Popovski, P.; Mange, G.; Gozalvez -Serrano, D.; Rosowski, T.; Zimmermann, G.; Agyapong, P.; Fallgren, M.... (2014). D6.6 Final report on the METIS 5G system concept and technology roadmap. http://hdl.handle.net/10251/7676
A New Method for the Characterization of Strain-Specific Conformational Stability of Protease-Sensitive and Protease-Resistant PrPSc
Although proteinacious in nature, prions exist as strains with specific self-perpetuating biological properties. Prion strains are thought to be associated with different conformers of PrPSc, a disease-associated isoform of the host-encoded cellular protein (PrPC). Molecular strain typing approaches have been developed which rely on the characterization of protease-resistant PrPSc. However, PrPSc is composed not only of protease-resistant but also of protease-sensitive isoforms. The aim of this work was to develop a protocol for the molecular characterization of both, protease-resistant and protease-sensitive PrPSc aggregates. We first set up experimental conditions which allowed the most advantageous separation of PrPC and PrPSc by means of differential centrifugation. The conformational solubility and stability assay (CSSA) was then developed by measuring PrPSc solubility as a function of increased exposure to GdnHCl. Brain homogenates from voles infected with human and sheep prion isolates were analysed by CSSA and showed strain-specific conformational stabilities, with mean [GdnHCl]1/2 values ranging from 1.6 M for MM2 sCJD to 2.1 for scrapie and to 2.8 M for MM1/MV1 sCJD and E200K gCJD. Interestingly, the rank order of [GdnHCl]1/2 values observed in the human and sheep isolates used as inocula closely matched those found following transmission in voles, being MM1 sCJD the most resistant (3.3 M), followed by sheep scrapie (2.2 M) and by MM2 sCJD (1.6 M). In order to test the ability of CSSA to characterise protease-sensitive PrPSc, we analysed sheep isolates of Nor98 and compared them to classical scrapie isolates. In Nor98, insoluble PrPSc aggregates were mainly protease-sensitive and showed a conformational stability much lower than in classical scrapie. Our results show that CSSA is able to reveal strain-specified PrPSc conformational stabilities of protease-resistant and protease-sensitive PrPSc and that it is a valuable tool for strain typing in natural hosts, such as humans and sheep
Appraising the intention of other people: Ecological validity and procedures for investigating effects of lighting for pedestrians
One of the aims of outdoor lighting public spaces such as pathways and subsidiary roads is to help pedestrians to evaluate the intentions of other people. This paper discusses how a pedestrians’ appraisal of another persons’ intentions in artificially lit outdoor environments can be studied. We review the visual cues that might be used, and the experimental design with which effects of changes in lighting could be investigated to best resemble the pedestrian experience in artificially lit urban environments. Proposals are made to establish appropriate operationalisation of the identified visual cues, choice of methods and measurements representing critical situations. It is concluded that the intentions of other people should be evaluated using facial emotion recognition; eye tracking data suggest a tendency to make these observations at an interpersonal distance of 15 m and for a duration of 500 ms. Photographs are considered suitable for evaluating the effect of changes in light level and spectral power distribution. To support investigation of changes in spatial distribution further investigation is needed with 3D targets. Further data are also required to examine the influence of glare
- …