200 research outputs found

    The application of a phycocyanin extract obtained from Arthrospira platensis as a blue natural colorant in beverages

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    AbstractCurrently, the food additive industry has interest in replacing artificial dyes with natural pigments, trying to maintain consumer interest and increase their awareness towards healthy diets. Phycobiliproteins are light-harvesting and water-soluble proteins extracted from cyanobacteria and red algae that can be employed as natural additives. In the present work, a C-phycocyanin extract from the cyanobacterium Arthrospira platensis was tested as blue colorant in beverages to demonstrate that samples containing the protein extract have a color similar to marketed beverages containing synthetic dyes. Using spectroscopy and colorimetry, the extract was characterized and gave evidence of having good properties and good stability in the pH range between 3.0 and 9.0. The staining factors, representing the amount of blue protein needed to reproduce the color of bluish commercial samples, ranged between 15.6 and 111.7 mg·L−1, being sufficiently low in all samples. Additionally, color stability during a short period of cold storage was studied: it demonstrated that isotonic and tonic beverages remained stable throughout the 11-days analysis period with no significant changes. These results prove that the C-phycocyanin extract has potential applications in food as natural colorant, being an alternative option to synthetic coloring molecules

    Threat modulates perception of looming visual stimuli

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    SummaryAmong the most critical of visual functions is the detection of potentially hazardous or threatening aspects of the environment. For example, objects on a collision course with an observer must be quickly identified to allow sufficient time to prepare appropriate defensive or avoidant responses. Directly approaching objects produce a specific accelerating pattern of optical expansion, known as ‘looming, which in theory exactly specifies time-to-collision independent of object size or distance. Such looming stimuli have been shown to trigger stereotyped defensive responses in both monkeys [1] and human infants [2]. Psychophysical results in adult participants have similarly suggested sensitivity to looming at early stages of visual processing [3]. Such findings indicate specialization of the visual system to detect and react to such ‘looming’ stimuli, and have contributed to the traditional view of looming as a purely optical cue to imminent collision [1]. Here, we investigated whether the semantic content of a looming visual stimulus affects perceived time-to-collision by manipulating its threat value. We show that time-to-collision is underestimated for threatening (snakes and spiders) compared to non-threatening (butterflies and rabbits) stimuli. Further, the magnitude of this effect is correlated with self-reported fear. Our results demonstrate affective modulation of the perception of looming stimuli, and suggest that emotion shapes basic aspects of visual perception

    Investigating energy saving potential in a big shopping center through ventilation control

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    This paper investigates energy saving measures for the ventilation system of large shopping centers. This kind of buildings is characterized by high yearly energy consumptions, because of the high level of operating hours and the frequent use of obsolete technologies. In the analyzed case studies, three big Do It Yourself (DIY) shops, located in Italy, are considered. Two different approaches are considered, they are aimed at reducing the annual energy consumption for the indoor air exchange of the sales area. The first considered retrofit solution consists in the installation of heat recovery exchangers, reducing the energy demand for the air thermal treatment without changing the airflow value. In the second scenario, smart air quality sensors are inputs for the modulation of the air exchange rate according to the actual requirement for indoor air quality. In a third scenario, the application of both retrofit solutions is considered. For each scenario, the paper reports the yearly energy savings, the avoided CO2 emissions and cost saving indicators. Furthermore, as the three shops are equipped with different heating systems and are located in different parts of Italy, a technological and climatic comparison is provided

    A Conceptual Review on Using Consequential Life Cycle Assessment Methodology for the Energy Sector

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    Energy is engaged in the supply chain of many economic sectors; therefore, the environmental impacts of the energy sector are indirectly linked to those of other sectors. Consequential life cycle assessment (CLCA) is an appropriate methodology to examine the direct and indirect environmental impacts of a product due to technological, economic or social changes. To date, different methodological approaches are proposed, combining economic and environmental models. This paper reviews the basic concept of CLCA and the coupling of economic and environmental models for performing CLCA in the energy sector during the period 2006\u20132020, with the aim to provide a description of the different tools, highlighting their strengths and limitations. From the review, it emerges that economic modelling tools are frequently used in combination with environmental data for CLCA in the energy sector, including equilibrium, input-output, and dynamic models. Out of these, the equilibrium model is the most widely used, showing some strengths in availability of data and energy system modelling tools. The input-output model allows for describing both direct and indirect effects due to changes in the energy sector, by using publicly available data. The dynamic model is less frequently applied due to its limitation in availability of data and modelling tools, but has recently attracted more attention due to the ability in modelling quantitative and qualitative indicators of sustainability

    Multi-objective optimization of building life cycle performance. A housing renovation case study in Northern Europe

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    While the operational energy use of buildings is often regulated in current energy saving policies, their embodied greenhouse gas emissions still have a considerable mitigation potential. The study aims at developing a multi-objective optimization method for design and renovation of buildings incorporating the operational and embodied energy demands, global warming potential, and costs as objective functions. The optimization method was tested on the renovation of an apartment building in Denmark, mainly focusing envelope improvements as roof and exterior wall insulation and windows. Cellulose insulation has been the predominant result, together with fiber cement or aluminum-based cladding and 2-layered glazing. The annual energy demand has been reduced from 166.4 to a range between 76.5 and 83.7 kWh/(m2 y) in the optimal solutions. The fact that the legal requirements of 70 kWh/(m2 y) are nearly met without building service improvements indicates that energy requirements can be fulfilled without compromising greenhouse gas emissions and cost. Since the method relies on standard national performance reporting tools, the authors believe that this study is a preliminary step towards more cost-efficient and low-carbon building renovations by utilizing multi-optimization techniques

    Regulatory T cells with multiple suppressive and potentially pro-tumor activities accumulate in human colorectal cancer

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    Tregs can contribute to tumor progression by suppressing antitumor immunity. Exceptionally, in human colorectal cancer (CRC), Tregs are thought to exert beneficial roles in controlling pro-tumor chronic inflammation. The goal of our study was to characterize CRC-infiltrating Tregs at multiple levels, by phenotypical, molecular and functional evaluation of Tregs from the tumor site, compared to non-tumoral mucosa and peripheral blood of CRC patients. The frequency of Tregs was higher in mucosa than in blood, and further significantly increased in tumor. Ex vivo, those Tregs suppressed the proliferation of tumor-infiltrating CD8+ and CD4+ T cells. A differential compartmentalization was detected between Helioshigh and Helioslow Treg subsets (thymus-derived versus peripherally induced): while Helioslow Tregs were enriched in both sites, only Helioshigh Tregs accumulated significantly and specifically in tumors, displayed a highly demethylated TSDR region and contained high proportions of cells expressing CD39 and OX40, markers of activation and suppression. Besides the suppression of T cells, Tregs may contribute to CRC progression also through releasing IL-17, or differentiating into Tfr cells that potentially antagonize a protective Tfh response, events that were both detected in tumor-associated Tregs. Overall, our data indicate that Treg accumulation may contribute through multiple mechanisms to CRC establishment and progression

    Flexibility Services to Minimize the Electricity Production from Fossil Fuels. A Case Study in a Mediterranean Small Island

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    The design of multi-carrier energy systems (MES) has become increasingly important in the last decades, due to the need to move towards more efficient, flexible and reliable power systems. In a MES, electricity, heating, cooling, water and other resources interact at various levels, in order to get optimized operation. The aim of this study is to identify the optimal combination of components, their optimal sizes and operating schedule allowing minimizing the annual cost for meeting the energy demand of Pantelleria, a Mediterranean island. Starting from the existing energy system (comprising diesel generators, desalination plant, freshwater storage, heat pumps and domestic hot water storages) the installation of solar resources (photovoltaic and solar thermal) and electrical storage were considered. In this way, the optimal scheduling of storage units injections, water desalination operation and domestic hot water production was deduced. An energy hub model was implemented using MATLAB to represent the problem. All equations in the model are linear functions, and variables are real or integer. Thus, a mixed integer linear programming algorithm was used for the solution of the optimization problem. Results prove that the method allows a strong reduction of operating costs of diesel generators also in the existing configuration

    Wearable and interactive mixed reality solutions for fault diagnosis and assistance in manufacturing systems: Implementation and testing in an aseptic bottling line

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    Abstract Thanks to the spread of technologies stemming from the fourth industrial revolution, also the topic of fault diagnosis and assistance in industrial contexts has benefited. Indeed, several smart tools were developed for assisting with maintenance and troubleshooting, without interfering with operations and facilitating tasks. In line with that, the present manuscript aims at presenting a web smart solution with two possible applications installed on an Android smartphone and Microsoft HoloLens. The solution aims at alerting the operators when an alarm occurs on a machine through notifications, and then at providing the instructions needed for solving the alarm detected. The two devices were tested by the operators of an industrial aseptic bottling line consisting of five machines in real working conditions. The usability of both devices was positively rated by these users based on the System Usability Scale (SUS) and additional appropriate statements. Moreover, the in situ application brought out the main difficulties and interesting issues for the practical implementation of the solutions tested

    Hopkins’ syndrome

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    Hopkins’ syndrome is a rare disease that affects the anterior horn of the spinal cord after an acute episode of asthma in children with atopic disease. A viral infection or immunological suppression in atopic subjects might be the cause of occurrence of this syndrome, although the mechanism due to the etiopathogenesis of the disease still remains unknown.In general, this disease is manifested by a few days to a few weeks after an acute asthma attack, with flaccid paralysis of one or more limbs and in some cases residual muscle atrophy. The response to corticosteroid therapy is good and rare the possibility of recurrence
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