An evaluation of clone detection techniques for identifying crosscutting concerns

Code implementing a crosscutting concern is often spread over many different parts of an application. Identifying such code automatically greatly improves both the maintainability and the evolvability of the application. First of all, it allows a developer to more easily find the places in the code that must be changed when the concern changes, and thus makes such changes less time consuming and less prone to errors. Second, it allows a developer to refactor the code, so that it uses modern and more advanced abstraction mechanisms, thereby restoring its modularity. In this paper, we evaluate the suitability of clone detection as a technique for the identification of crosscutting concerns. To that end, we manually identify four specific concerns in an industrial C application, and analyze to what extent clone detection is capable of finding these concerns. We consider our results as a stepping stone toward an automated 'concern miner' based on clone detection

Effects of TENS and methylphenidate in tuberculous meningo-encephalistis

Primary objective: Beneficial effects of transcutaneous electrical nerve stimulation (TENS) on cognition and behaviour were observed in a child with probable Herpes Simplex Encephalitis. Based on these positive findings, it was examined in the present case study whether a child who had been diagnosed to suffer from tuberculous meningitis would benefit from TENS. Furthermore, as aggression and overactive behaviour were also prominent clinical symptoms, the effects of methylphenidate were investigated. Methods and Procedures: Neuropsychological tests were used to assess attention/concentration and visuospatial and visuoconstructive memory. Behaviour, including the level of activity during 24 hours, was assessed by one observation scale and actigraphy. Experimental interventions: TENS and methylphenidate. Main outcomes and results: TENS particularly improved overall affective behaviour. Methylphenidate appeared to have the opposite effect on cognition and hardly any effect on patient's behaviour. Conclusions: TENS might improve the patient's behavioural functioning. Pros and cons for treatment effects are discussed

Mutation Testing as a Safety Net for Test Code Refactoring

Refactoring is an activity that improves the internal structure of the code without altering its external behavior. When performed on the production code, the tests can be used to verify that the external behavior of the production code is preserved. However, when the refactoring is performed on test code, there is no safety net that assures that the external behavior of the test code is preserved. In this paper, we propose to adopt mutation testing as a means to verify if the behavior of the test code is preserved after refactoring. Moreover, we also show how this approach can be used to identify the part of the test code which is improperly refactored

AML1, the Target of Multiple Chromosomal Translocations in Human Leukemia, Is Essential for Normal Fetal Liver Hematopoiesis

AbstractThe AML1–CBFβ transcription factor is the most frequent target of chromosomal rearrangements in human leukemia. To investigate its normal function, we generated mice lacking AML1. Embryos with homozygous mutations in AML1 showed normal morphogenesis and yolk sac–derived erythropoiesis, but lacked fetal liver hematopoiesis and died around E12.5. Sequentially targeted AML1−/− ES cells retained their capacity to differentiate into primitive erythroid cells in vitro; however, no myeloid or erythroid progenitors of definitive hematopoietic origin were detected in either the yolk sac or fetal livers of mutant embryos. Moreover, this hematopoietic defect was intrinsic to the stem cells in that AML1−/− ES cells failed to contribute to hematopoiesis in chimeric animals. These results suggest that AML1-regulated target genes are essential for definitive hematopoiesis of all lineages

ras Oncogene Activation Does Not Induce Sensitivity to Natural Killer Cell—Mediated Lysis in Human Melanoma

An important phenomenon in tumor immunology that has come under recent attention is the impact of oncogene activation in tumor cells on the sensitivity to lysis by immune effector cells. Several studies suggested that transfer of an activated ras oncogene into cultured rodent fibroblasts induces susceptibility to natural killer cell (NK)-mediated lysis. Experiments using human tumor cells, however, have produced conflicting data on the effect of ras activation in this respect. In studying the activation of the oncogene c-myc, which is often overexpressed in human melanoma, we have found that in cell lines expressing high levels of Myc protein, the sensitivity to lysis by NK cells was dramatically increased due to reduced expression of Human Leukocyte Antigen B locus products. Since the N-ras oncogene was found to be activated in 15% of human melanomas, we examined the possibility that in melanoma, in analogy to the murine systems, the mutated ras oncogene may influence NK susceptibility of human melanoma cells. Two N-ras genes harboring frequently found mutations were cloned into an expression vector. Transfection of the IGR39D melanoma cell line with wildtype and mutant N-ras constructs yielded several ras-expressing clones that were tested for NK sensitivity. Neither high expression of the wildtype N-ras protein, nor expression of two mutant proteins (N61-arg, N61-lys) was shown to result in enhanced NK-mediated lysis. We conclude that activation of ras oncogenes does not lead to the induction of an NK-sensitive phenotype in human melanoma cells. J Invest Dermatol 103:117S–121S, 199

Choir singing and health status in people affected by cancer

Cancer survival rates have improved dramatically over recent years, however, health-related quality of life (HRQoL) for many patients, survivors and their families remains low even after successful treatment. This mixed-methods observational study explored the effects of participation in community choirs on HRQoL in individuals who have had cancer (patients) or have been affected by cancer (non-patients). This included a longitudinal analysis of choristers commencing the Tenovus Cancer Care “Sing with Us” choirs across Wales and a series of semi-structured interviews and focus groups. Participants completed the Short-form 36 and the Hospital Anxiety and Depression Scale on commencement of the choir and 3 and 6 months later. On joining the choir, several domains of the SF36 were lower, indicating worse HRQoL and greater depression in patients than non-patients (p < .05). In patients, choir participation improved vitality, overall mental health and anxiety. In non-patients, choir participation improved anxiety (p < .05). Participants experienced the choirs as both an uplifting musical activity and a supportive community group. The results support the provision of a spectrum of support options to meet the different needs and preferences of people affected by cancer

Optimizing the reliability and resource efficiency of MapReduce-based systems

Debido al gran incremento de datos digitales que ha tenido lugar en los últimos años, ha surgido un nuevo paradigma de computación paralela para el procesamiento eficiente de grandes volúmenes de datos. Muchos de los sistemas basados en este paradigma, también llamados sistemas de computación intensiva de datos, siguen el modelo de programación de Google MapReduce. La principal ventaja de los sistemas MapReduce es que se basan en la idea de enviar la computación donde residen los datos, tratando de proporcionar escalabilidad y eficiencia. En escenarios libres de fallo, estos sistemas generalmente logran buenos resultados. Sin embargo, la mayoría de escenarios donde se utilizan, se caracterizan por la existencia de fallos. Por tanto, estas plataformas suelen incorporar características de tolerancia a fallos y fiabilidad. Por otro lado, es reconocido que las mejoras en confiabilidad vienen asociadas a costes adicionales en recursos. Esto es razonable y los proveedores que ofrecen este tipo de infraestructuras son conscientes de ello. No obstante, no todos los enfoques proporcionan la misma solución de compromiso entre las capacidades de tolerancia a fallo (o de manera general, las capacidades de fiabilidad) y su coste. Esta tesis ha tratado la problemática de la coexistencia entre fiabilidad y eficiencia de los recursos en los sistemas basados en el paradigma MapReduce, a través de metodologías que introducen el mínimo coste, garantizando un nivel adecuado de fiabilidad. Para lograr esto, se ha propuesto: (i) la formalización de una abstracción de detección de fallos; (ii) una solución alternativa a los puntos únicos de fallo de estas plataformas, y, finalmente, (iii) un nuevo sistema de asignación de recursos basado en retroalimentación a nivel de contenedores. Estas contribuciones genéricas han sido evaluadas tomando como referencia la arquitectura Hadoop YARN, que, hoy en día, es la plataforma de referencia en la comunidad de los sistemas de computación intensiva de datos. En la tesis se demuestra cómo todas las contribuciones de la misma superan a Hadoop YARN tanto en fiabilidad como en eficiencia de los recursos utilizados. ABSTRACT Due to the increase of huge data volumes, a new parallel computing paradigm to process big data in an efficient way has arisen. Many of these systems, called dataintensive computing systems, follow the Google MapReduce programming model. The main advantage of these systems is based on the idea of sending the computation where the data resides, trying to provide scalability and efficiency. In failure-free scenarios, these frameworks usually achieve good results. However, these ones are not realistic scenarios. Consequently, these frameworks exhibit some fault tolerance and dependability techniques as built-in features. On the other hand, dependability improvements are known to imply additional resource costs. This is reasonable and providers offering these infrastructures are aware of this. Nevertheless, not all the approaches provide the same tradeoff between fault tolerant capabilities (or more generally, reliability capabilities) and cost. In this thesis, we have addressed the coexistence between reliability and resource efficiency in MapReduce-based systems, looking for methodologies that introduce the minimal cost and guarantee an appropriate level of reliability. In order to achieve this, we have proposed: (i) a formalization of a failure detector abstraction; (ii) an alternative solution to single points of failure of these frameworks, and finally (iii) a novel feedback-based resource allocation system at the container level. Finally, our generic contributions have been instantiated for the Hadoop YARN architecture, which is the state-of-the-art framework in the data-intensive computing systems community nowadays. The thesis demonstrates how all our approaches outperform Hadoop YARN in terms of reliability and resource efficiency

Fermi Surface Properties of Low Concentration Cex_{x}La1−x_{1-x}B6_{6}: dHvA

The de Haas-van Alphen effect is used to study angular dependent extremal areas of the Fermi Surfaces (FS) and effective masses of Ce$_{x}$La$_{1-x}$B$_{6}$ alloys for $x$ between 0 and 0.05. The FS of these alloys was previously observed to be spin polarized at low Ce concentration ($x$ = 0.05). This work gives the details of the initial development of the topology and spin polarization of the FS from that of unpolarized metallic LaB$_{6}$ to that of spin polarized heavy Fermion CeB$_{6}$ .Comment: 7 pages, 9 figures, submitted to PR