Civic Engagement and Service Learning Partnerships

Service learning is designed to promote volunteerism and civic awareness. Community engagement in higher education specifically involves university members partnering with local community organizations to address a need. Students engage with community partners through service learning and other activities (Moore & Mendez, 2014). Service learning is a practice that connects new knowledge and social responsibility through active learning (Benson & Younkin, 1996).https://digitalscholarship.unlv.edu/btp_expo/1083/thumbnail.jp

Efficiently Clustering Very Large Attributed Graphs

Attributed graphs model real networks by enriching their nodes with attributes accounting for properties. Several techniques have been proposed for partitioning these graphs into clusters that are homogeneous with respect to both semantic attributes and to the structure of the graph. However, time and space complexities of state of the art algorithms limit their scalability to medium-sized graphs. We propose SToC (for Semantic-Topological Clustering), a fast and scalable algorithm for partitioning large attributed graphs. The approach is robust, being compatible both with categorical and with quantitative attributes, and it is tailorable, allowing the user to weight the semantic and topological components. Further, the approach does not require the user to guess in advance the number of clusters. SToC relies on well known approximation techniques such as bottom-k sketches, traditional graph-theoretic concepts, and a new perspective on the composition of heterogeneous distance measures. Experimental results demonstrate its ability to efficiently compute high-quality partitions of large scale attributed graphs.Comment: This work has been published in ASONAM 2017. This version includes an appendix with validation of our attribute model and distance function, omitted in the converence version for lack of space. Please refer to the published versio

The effect of spatial resolution on optical and near-IR studies of stellar clusters: Implications for the origin of the red excess

Recent ground based near-IR studies of stellar clusters in nearby galaxies have suggested that young clusters remain embedded for 7-10Myr in their progenitor molecular cloud, in conflict with optical based studies which find that clusters are exposed after 1-3Myr. Here, we investigate the role that spatial resolution plays in this apparent conflict. We use a recent catalogue of young ($5000$~\msun) clusters in the nearby spiral galaxy, M83, along with Hubble Space Telescope (HST) imaging in the optical and near-IR, and ground based near-IR imaging, to see how the colours (and hence estimated properties such as age and extinction) are affected by the aperture size employed, in order to simulate studies of differing resolution. We find that the near-IR is heavily affected by the resolution, and when aperture sizes $>40$~pc are used, all young/blue clusters move red-ward in colour space, which results in their appearance as heavily extincted clusters. However, this is due to contamination from nearby sources and nebular emission, and is not an extinction effect. Optical colours are much less affected by resolution. Due to the larger affect of contamination in the near-IR, we find that, in some cases, clusters will appear to show near-IR excess when large ($>20$~pc) apertures are used. Our results explain why few young ($<6$~Myr), low extinction (\av < 1~mag) clusters have been found in recent ground based near-IR studies of cluster populations, while many such clusters have been found in higher resolution HST based studies. Additionally, resolution effects appear to (at least partially) explain the origin of the near-IR excess that has been found in a number of extragalactic YMCs.Comment: 8 pages, 5 figures, accepted for publication in MNRA

The impacts of replacing air bubbles with microspheres for the clarification of algae from low cell-density culture

Dissolved Air Flotation (DAF) is a well-known coagulation–flotation system applied at large scale for microalgae harvesting. Compared to conventional harvesting technologies DAF allows high cell recovery at lower energy demand. By replacing microbubbles with microspheres, the innovative Ballasted Dissolved Air Flotation (BDAF) technique has been reported to achieve the same algae cell removal efficiency, while saving up to 80% of the energy required for the conventional DAF unit. Using three different algae cultures (Scenedesmus obliquus, Chlorella vulgaris and Arthrospira maxima), the present work investigated the practical, economic and environmental advantages of the BDAF system compared to the DAF system. 99% cells separation was achieved with both systems, nevertheless, the BDAF technology allowed up to 95% coagulant reduction depending on the algae species and the pH conditions adopted. In terms of floc structure and strength, the inclusion of microspheres in the algae floc generated a looser aggregate, showing a more compact structure within single cell alga, than large and filamentous cells. Overall, BDAF appeared to be a more reliable and sustainable harvesting system than DAF, as it allowed equal cells recovery reducing energy inputs, coagulant demand and carbon emissions

Sustainable Approaches for the Additive Manufacturing of Ceramic Materials

Additive manufacturing technologies collectively refer to a set of layer-wise deposition methods that typically rely on CAD-CAM approaches for obtaining products with a complex shape/geometry and high precision and reliability. If the additive manufacturing of polymers is relatively easy and scalable due to the low temperatures needed to obtain processable inks, using similar technologies to fabricate ceramic products is indeed more challenging and expensive but, on the other hand, allows for obtaining high-quality results that would not be achievable through conventional methods. Furthermore, the implementation of additive manufacturing allows for the addressing of some important concerns related to the environment and sustainability, including the minimization of resource depletion and waste production/disposal. Specifically, additive manufacturing technologies can provide improvements in energy consumption and production costs, besides obtaining less waste material and less CO2 emissions, which are all key points in the context of the circular economy. After providing an overview of the additive manufacturing methods which are specifically applied to ceramics, this review presents the sustainability elements of these processing strategies, with a focus on both current and future benefits. The paucity of specific available studies in the literature—which are included and discussed in this review—suggests that the research on additive manufacturing sustainability in the field of ceramic materials is in the preliminary stage and that more relevant work still deserves to be carried out in the future to explore this fascinating field at the boundary among ceramics science/technology, production engineering and waste management

Papillomavirus from the bench to the clinics

[Excerpt] Human papillomavirus (HPV) represents an exciting subject of study because it is currently established as an essential etiological factor of uterine cervical cancer and strongly implicated in the development of other genital cancers as well, in addition to benign genital warts. Additionally, substantial amount of new data have been elaborated linking HPV with head and neck cancer and, more tentatively, also with esophageal, breast, prostate, and lung cancers. Despite the existing controversies, the possible link of HPV infection with these nongenital carcinomas opens a new fascinating era of HPV research. [...

Facilities components’ reliability & maintenance services self-rating through big data processing

The availability of big data in the information modelling of buildings can be useful to improve maintenance strategies and activities that are integrated in a digital twin. In some countries, such as Italy, tender specifications for public works must avoid any reference to specific brands and models, both in building design and maintenance services: quality levels and service-life objectives must be defined solely through performance specifications with reference to national or international standards. This could be a critical issue when considering reliability and serviceability of facility components, because there are no official methods about the ratings or measurements on the aforementioned performances. To help solving this concern, a method is proposed to broaden the scope of the big data collected from IoT applied to facility components, so as to feed a general and public database capable of normalizing data on faults and the effects of maintenance interventions, e.g. by correlating them with actual running times and operating conditions. In this way, each component on the market can theoretically feed a public and accessible database that collects reports on the occurrence of faults and the maintenance results, thus statistically processing its propensity for durability, the effectiveness of maintenance, the maintainability propensity of components as well as their reliability (e.g. by assessing the interval between maintenance interventions). In this way, a standardization of reliability, maintainability and durability performances ratings for components and serviceability performance rating for facility maintenance services could boost the facility quality design and improve the maintenance management

Statistical analysis of nutrient data quality (nitrate and phosphate), applied to useful predictor models in the northwestern Mediterranean Sea

Se ha analizado estadísticamente un conjunto de datos de 12 campañas oceanográficas (realizadas de 1979 a 1983), abarcando dos regiones en el mar Mediterráneo noroccidental (golfo de León y mar Catalán), relacionando el nitrato y el fosfato con el silicato, la salinidad y la profundidad. El análisis ha proporcionado una visión de la calidad de los datos y un modelo de predicción para estos nutrientes por debajo de la capa superficial. Los resultados del análisis estadístico han mostrado que las ecuaciones de regresión (nitrato- profundidad y fosfato-salinidad) de algunas campañas del golfo de León no presentaron diferencias significativas (P = 0,05), indicando que estas relaciones no cambian en esta área, principalmente en verano y otoño. Se puede observar una relación significativa entre nitrato y fosfato con salinidad y profundidad (regresión múltiple), sugiriendo que las distribuciones del nitrato y del fosfato en la capa intermedia están relacionadas con la mezcla de las masas de agua y la degradación de la materia orgánica. Los datos de fosfato mostraron una variancia elevada y errores, probablemente debido a cuestiones de metodología y análisis químico. Por debajo de la masa de Agua Levantina Intermedia, los resultados del ANOVA han mostrado que no hay una variación significativa de las concentraciones de nitrato y fosfato en la columna de agua. Por otro lado, se puede observar una variación espacial y temporal en esta capa.A dataset comprising 12 oceanographic cruises (from 1979 to 1983), covering two regions in the Northwestern Mediterranean Sea (Gulf of Lyon and Catalan Sea), was statistically analysed for nitrate and phosphate relationships with silicate, salinity and depth. This analysis provided a preliminary assessment of the data's quality, as well as a predictor model of these nutrients below the surface layer. Results from the statistical analysis showed no significant difference (P = 0.05), between the regression equations (nitrate-depth and phosphate-salinity) of most cruises in the Gulf of Lyon, indicating that these relationships do not change in this area, particularly in summer and autumn. A significant relationship between nitrate and phosphate with salinity and depth (multiple regression) was observed, suggesting that nitrate and phosphate distribution in the intermediate level are significantly related to the mixture of the water masses and the degradation of organic matter. The phosphate data showed a wide variance and a bias, probably due to procedural problems in the chemical analysis. Below the Intermediate Levantine Water, results from the ANOVA showed no significant variation of the phosphate and nitrate concentrations in the water column. However, a spatial and temporal variation was observed in this level.Instituto Español de Oceanografí