Ventilative Cooling in Shopping Centers' Retrofit: The Mercado Del Val Case Study ☆

Abstract Nearly all retail locations use ventilation and cooling systems to ensure adequate air exchange for health reasons and indoor comfort temperatures. These systems can run for over 2,000 hours per year and we expect that average operating hours will continue to rise across Europe because of the continued trend towards longer opening hours and increased number of opening days. Shopping malls often enclose large open spaces and atria with high solar and internal gains that can drive ventilative cooling. This paper presents the ventilative cooling strategy proposed, analysed and implemented in one of the three demo cases of the project: Mercado del Val, the historic market of the city of Valladolid. Once we determined the climate suitability, we defined a ventilative cooling strategy that exploits openings in the facade and in the skylight to promote stack effect ventilation. Considering that indoor spaces of a shopping centre highly interacts among each other, a multizone based analysis of airflows is needed to evaluate the ventilative cooling strategy effectiveness and to assess potential energy savings. We sized openings area and location on the facade, taking into account design constraints, and we assessed their performances in terms of energy, thermal comfort and indoor air quality. Results show the potential cooling load reduction, with the achievement of acceptable thermal comfort due to the ventilative cooling in the shopping mall. The analysis performed supported the design decision process towards cost effective low energy shopping centre

Occurrence and Effects on Weaning From Mechanical Ventilation of Intensive Care Unit Acquired and Diaphragm Weakness: A Pilot Study

PurposeLimb intensive care unit (ICU)-acquired weakness (ICUAW) and ICU acquired diaphragm weakness (DW) occur frequently in mechanically ventilated (MV) patients; their coexistence in cooperative and uncooperative patients is unknown. This study was designed to (1) describe the co-occurrence of the two conditions (2) evaluate the impact of ICUAW and DW on the ventilator-free days (VFDs) at 28 days and weaning success, and (3) assess the correlation between maximal inspiratory pressure (MIP) and thickening fraction (TFdi) in patients with DW.MethodsThis prospective pilot study was conducted in a single-center on 73 critically ill MV patients. Muscle weakness was defined as a Medical Research Council score < 48 in cooperative patients or a bilateral mean simplified peroneal nerve test < 5.26 mV in uncooperative patients. Diaphragm dysfunction was defined as MIP < 30 cm H2O or as a TFdi < 29%. Weaning success was defined according to weaning according to a new definition (WIND).ResultsFifty-seven patients (78%) had ICUAW and 59 (81%) had DW. The coexistence of the two conditions occurred in 48 patients (65%), without association (χ2 = 1.06, p = 0.304). In the adjusted analysis, ICUAW was independently related to VFDs at 28-days (estimate difference 6 days, p = 0.016), and WIND (OR of 3.62 for having WIND different than short weaning), whereas DW was not. The linear mixed model showed a significant but weak correlation between MIP and TFdi (p < 0.001).ConclusionThis pilot study is the first to explore the coexistence of ICUAW and DW in both cooperative and uncooperative patients; a lack of association was found between DW and ICUAW when considering both cooperative and uncooperative patients. We found a strong correlation between ICUAW but not DW with the VFDs at 28 days and weaning success. A future larger study is warranted in order to confirm our results, and should also investigate the use of transdiaphragmatic twitch pressure measurement during bilateral anterior magnetic phrenic nerve stimulation for the diagnosis of DW

Traces of trauma – a multivariate pattern analysis of childhood trauma, brain structure and clinical phenotypes

Background: Childhood trauma (CT) is a major yet elusive psychiatric risk factor, whose multidimensional conceptualization and heterogeneous effects on brain morphology might demand advanced mathematical modeling. Therefore, we present an unsupervised machine learning approach to characterize the clinical and neuroanatomical complexity of CT in a larger, transdiagnostic context. Methods: We used a multicenter European cohort of 1076 female and male individuals (discovery: n = 649; replication: n = 427) comprising young, minimally medicated patients with clinical high-risk states for psychosis; patients with recent-onset depression or psychosis; and healthy volunteers. We employed multivariate sparse partial least squares analysis to detect parsimonious associations between combinations of items from the Childhood Trauma Questionnaire and gray matter volume and tested their generalizability via nested cross-validation as well as via external validation. We investigated the associations of these CT signatures with state (functioning, depressivity, quality of life), trait (personality), and sociodemographic levels. Results: We discovered signatures of age-dependent sexual abuse and sex-dependent physical and sexual abuse, as well as emotional trauma, which projected onto gray matter volume patterns in prefronto-cerebellar, limbic, and sensory networks. These signatures were associated with predominantly impaired clinical state- and trait-level phenotypes, while pointing toward an interaction between sexual abuse, age, urbanicity, and education. We validated the clinical profiles for all three CT signatures in the replication sample. Conclusions: Our results suggest distinct multilayered associations between partially age- and sex-dependent patterns of CT, distributed neuroanatomical networks, and clinical profiles. Hence, our study highlights how machine learning approaches can shape future, more fine-grained CT research

Systemic solution-sets

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Bulk airflow measurements in a large naturally ventilated atrium in a mild climate

In recent years, concerns about global warming and greenhouse gas emissions have motivated designers to reduce building energy consumption through the implementation of passive solutions without compromising users’ thermal comfort. This evidence has stimulated a renewed interest in designers for the exploitation of natural ventilation as means of passive cooling solutions. The adoption of ventilative cooling is particularly suitable for large spaces (non-residential buildings) as a measure to reduce the HVAC system high cooling loads. Due the inability to control and ensure a constant airflow rate through natural ventilation most of the times designers choice goes towards mixed-mode buildings. Mixed-mode buildings are designed in such a way that the HVAC system acts as backup to prevent uncomfortable conditions when natural ventilation is not sufficient to guarantee a comfortable environment. Unfortunately, information about the actual performance of mixed-mode buildings is difficult to obtain due the difficulties to set up measurements in naturally ventilated buildings that highly depend on building geometry and outdoor conditions (weather, pollution and noise). This limitation leads designers to follow a traditional design approach based on mechanical air conditioned systems. With the aim of reducing the lack of information about the actual performance of mixed-mode non-residential buildings, this paper presents a full-scale bulk air flow measurements for a large naturally ventilated atrium in a mild climate. The methodology and the results presented in this paper refers at the first step of a more complete and complex work which aims at assessing the performance of the large mixed-mode atrium. The general performance of the atrium are tested through a long term measurement campaign which is indeed ongoing. The final aim is to quantify the effect of ventilative night cooling in term of cooling energy reduction and indoor thermal environment

Guidelines on retrofitting of shopping malls

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Guidelines on how to approach the energy-efficient retrofitting of shopping centres

Special architectural conditions and needs are common in almost all shopping centres. The main retrofit drivers are: (i) improve the indoor environmental quality and functionality, to enhance the customers experience; (ii) reduce the energy consumption; (iii) optimize the building operation and relative maintenance costs and (iv) improve the overall sustainability level reducing the environmental, social, and economic impact. Shopping centres vary in their functions, typologies, forms and size, as well as the (shopping) trip purpose. To consider the shopping centre building stock as one segment with its own boundaries and trends, the EU FP7 CommONEnergy project set a shopping centre definition1: “A shopping centre is a formation of one or more retail buildings comprising units and ‘communal’ areas, which are planned and managed as a single entity related in its location, size and type of shops to the trade area that it serves.” The European wholesale and retail sector is the big marketplace of Europe, contributing with around 11% of the EU’s GDP2. Therefore, sustainability of the retail sector may significantly contribute to reaching the EU long-term environmental and energy goals. Within the retail sector, shopping centres are of particular interest due to: their structural complexity and multi-stakeholders’ decisional process, their high energy savings and carbon emissions reduction potential, as well as their importance and influence in shopping tendencies and lifestyle. A shopping centre is a building, or a complex of buildings, designed and built to contain many interconnected activities in different areas. Next to public spaces, there are areas related to work spaces, with different use and location and according to the shopping centre type. They have different opening hours and entrances than the shopping centre. Today, in addition to the mere commercial function, a shopping centre responds to several customer needs: it exhibits recreational attractions …publishedVersio