The role of pit lake thermal dynamics on the thermal performance of ground heat exchangers.

The addition of ground heat exchangers (GHEs) to a pit lake's basin has the potential for abundant, clean and renewable geothermal energy extraction using shallow geothermal systems. Basin-embedded GHEs avoid direct interaction with mine water, which has been shown to impact efficiency and longevity in mine open-loop geothermal systems negatively. The now accelerated closure of open-pit coal mines presents itself as an opportunity to use this technology. However, no guidelines currently exist for designing or operating GHEs embedded in the sediment of water bodies. Furthermore, the two-way coupling between the complex annual thermal fluid dynamics that lakes are naturally subjected to and heat fluxes on the sediments and the GHE system has not been explored. In this study, we develop and validate finite element models to assess the relevance of lake thermal stratification in the performance of a geothermal system embedded in water bodies basins, e.g., on open-pit mine closures, under temperate residential thermal loads. The results show that the pit lake's role as a thermal sink improves significantly when the lake's thermal dynamics are accounted for, with an increase of up to 292% in the lake's available energy budget. A minor variation in energy budget (~8%) was found whether the lake is modelled explicitly or simplified as a transient Dirichlet temperature boundary condition. This small difference vanishes if horizontal circulation along the lake is considered, highlighting the lake's thermal energy potential. Finally, the impact on the GHE Coefficient of Performance (COP) is evaluated, with a maximum of ~15% difference among all cases.

O2A: One-Shot Observational Learning with Action Vectors.

We present O2A, a novel method for learning to perform robotic manipulation tasks from a single (one-shot) third-person demonstration video. To our knowledge, it is the first time this has been done for a single demonstration. The key novelty lies in pre-training a feature extractor for creating a perceptual representation for actions that we call "action vectors". The action vectors are extracted using a 3D-CNN model pre-trained as an action classifier on a generic action dataset. The distance between the action vectors from the observed third-person demonstration and trial robot executions is used as a reward for reinforcement learning of the demonstrated task. We report on experiments in simulation and on a real robot, with changes in viewpoint of observation, properties of the objects involved, scene background and morphology of the manipulator between the demonstration and the learning domains. O2A outperforms baseline approaches under different domain shifts and has comparable performance with an Oracle (that uses an ideal reward function). Videos of the results, including demonstrations, can be found in our: project-website.

Inhibition of Wild Enterobacter cloacae Biofilm Formation by Nanostructured Graphene- and Hexagonal Boron Nitride-Coated Surfaces.

Although biofilm formation is a very effective mechanism to sustain bacterial life, it is detrimental in medical and industrial sectors. Current strategies to control biofilm proliferation are typically based on biocides, which exhibit a negative environmental impact. In the search for environmentally friendly solutions, nanotechnology opens the possibility to control the interaction between biological systems and colonized surfaces by introducing nanostructured coatings that have the potential to affect bacterial adhesion by modifying surface properties at the same scale. In this work, we present a study on the performance of graphene and hexagonal boron nitride coatings (h-BN) to reduce biofilm formation. In contraposition to planktonic state, we focused on evaluating the efficiency of graphene and h-BN at the irreversible stage of biofilm formation, where most of the biocide solutions have a poor performance. A wild Enterobacter cloacae strain was isolated, from fouling found in a natural environment, and used in these experiments. According to our results, graphene and h-BN coatings modify surface energy and electrostatic interactions with biological systems. This nanoscale modification determines a significant reduction in biofilm formation at its irreversible stage. No bactericidal effects were found, suggesting both coatings offer a biocompatible solution for biofilm and fouling control in a wide range of applications.

The Many Faces of Graphene as Protection Barrier. Performance under Microbial Corrosion and Ni Allergy Conditions.

In this work we present a study on the performance of CVD (chemical vapor deposition) graphene coatings grown and transferred on Ni as protection barriers under two scenarios that lead to unwanted metal ion release, microbial corrosion and allergy test conditions. These phenomena have a strong impact in different fields considering nickel (or its alloys) is one of the most widely used metals in industrial and consumer products. Microbial corrosion costs represent fractions of national gross product in different developed countries, whereas Ni allergy is one of the most prevalent allergic conditions in the western world, affecting around 10% of the population. We found that grown graphene coatings act as a protective membrane in biological environments that decreases microbial corrosion of Ni and reduces release of Ni2+ ions (source of Ni allergic contact hypersensitivity) when in contact with sweat. This performance seems not to be connected to the strong orbital hybridization that Ni and graphene interface present, indicating electron transfer might not be playing a main role in the robust response of this nanostructured system. The observed protection from biological environment can be understood in terms of graphene impermeability to transfer Ni2+ ions, which is enhanced for few layers of graphene grown on Ni. We expect our work will provide a new route for application of graphene as a protection coating for metals in biological environments, where current strategies have shown short-term efficiency and have raised health concerns.

Consumer perceptions, descriptive profile, and mechanical properties of a novel product with chickpea flour: Effect of ingredients.

Increasingly popular in the West is hummus, a spread that is made with pureed chickpeas and other healthful ingredients. The changes in texture measurements and sensory properties in a novel chickpea flour-based product occurring when water is partially replaced by common ingredients of hummus were investigated. Eleven chickpea gels containing different amounts of minced garlic, lemon juice, curry powder, and inulin were prepared and compared with two control gels. These ingredients were chosen to make the product tastier, appealing, and similar to hummus. Instrumental texture tests were carried out: uniaxial compression, stress relaxation, and texture profile analysis. Quantitative descriptive analysis was used to describe differences in sensory properties perceived by a trained panel, whereas repertory grid method combined with free choice profile was used to determine differences perceived by untrained consumers. Gels with higher curry powder content presented lower force to breakdown, whereas increasing inulin content led to gels with higher hardness. Principal component analysis was applied to instrumental parameters and quantitative descriptive analysis data, whereas generalized Procrustes analysis was applied to free choice profile data. This newly developed chickpea gel may make a nutrition claim with respect to protein ("high in protein," or at least a "source of protein").

Effects of Pressure, Temperature, Treatment Time, and Storage on Rheological, Textural, and Structural Properties of Heat-Induced Chickpea Gels.

Pressure-induced gelatinization of chickpea flour (CF) was studied in combination with subsequent temperature-induced gelatinization. CF slurries (with 1:5 flour-to-water ratio) and CF in powder form were treated with high hydrostatic pressure (HHP), temperature (T), and treatment time (t) at three levels (200, 400, 600 MPa; 10, 25, 50 °C; 5, 15, 25 min). In order to investigate the effect of storage (S), half of the HHP-treated CF slurries were immediately analyzed for changes in oscillatory rheological properties under isothermal heating at 75 °C for 15 min followed by cooling to 25 °C. The other half of the HHP-treated CF slurries were refrigerated (at 4 °C) for one week and subsequently analyzed for changes in oscillatory properties under the same heating conditions as the unrefrigerated samples. HHP-treated CF in powder form was analyzed for changes in textural properties of heat-induced CF gels under isothermal heating at 90 °C for 5 min and subsequent cooling to 25 °C. Structural changes during gelatinization were investigated using microscopy. Pressure had a more significant effect on rheological and textural properties, followed by T and treatment t (in that order). Gel aging in HHP-treated CF slurries during storage was supported by rheological measurements.

Accessory bronchus in a patient with chronic cough.

The accessory bronchus involving the trachea or main bronchi is very rare. In this report, we present images of an accessory bronchus, detected by computed tomography scan and flexible bronchoscopy. Our patient was suffering from persistent productive cough and had normal chest x-ray. We review the literature to establish relationship between our patient's symptoms and this congenital anomaly.

Consensus of the Spanish Society of Radiation Oncology (SEOR) Brachytherapy Group on Brachytherapy in breast cancer.

Breast cancer is the most frequent neoplasia in women. Randomized studies which compare mastectomy with conservative treatment show no differences in global survival. In cases in which conservative surgery is performed, breast radiation therapy and boost reduces the rate of local recurrence. On March 2010, the 8th Consensus Meeting of the Spanish Society for Radiation Oncology (SEOR) Brachytherapy Group was held in Madrid about «Treatment of Breast Cancer with Brachytherapy¼. In this article we presented the conclusions about brachytherapy boost, Partial breast irradiation and clinical dosimetry.

Granuloma inflamatorio secundario a la ingestion de espina de pescado: presentación de un caso y revisión de la literatura / Inflammatory granuloma following a fish bone swallowing

La ingestión de objetos extraños ocurre ocasionalmente en los adultos, especialmente en aquéllos que utilizan prótesis dentales. La mayoría de esos objetos transitan por el tracto gastrointestinal sin causar síntomas, aunque algunas veces se pueden presentar complicaciones como perforación, absceso, obstrucción, tumoración, peritonitis localizada o generalizada. Se informa el caso de una paciente que desarrolló una tumoración abdominal dependiente de intestino secundaria a la perforación de éste, como consecuencia de la ingestión de una espina de pescado. Se comunican los síntomas presentados y la dificultad diagnóstica, pues fue valorada por diferentes especialista sin logara llega a un diagnóstico de certeza. Cabe hacer notar la importancia del aspecto macroscópico de la tumoración, que sugería un proceso tumoral de características malignas, y que histopatológicamanete fue señalado como un granuloma inflamatorio libre de células malignas secundario a cuerpo extraño (espina de pescado), caso raro de acuerdo a la bibliografía revisada.