Trade-off between optimal design and operation in district cooling networks

Especially in densely populated areas, district cooling represents an opportunity to reduce energy consumption and emissions. Nevertheless, this technology is characterised by large capital costs which impede its diffusion. As a consequence, optimization tools can significantly help to unleash their potential. In this paper, a methodology is proposed to combinedly optimize the design and operation of a district cooling system based on a Mixed Integer Quadratic Programming. The model is compared to the design only optimization, based on a properly tailored heuristic approach. The models, when applied to a case study characterized by seasonal demand, provide similar solutions, which differ by 0.5 % in terms of objective value for a standard scenario. The simultaneous design and operation optimization does not provide sensible savings with respect to optimizing solely the design. A sensitivity analysis is performed to prove the robustness of the results. The results showed that the simulta- neous operation and design optimization would be limited to 1 % of total costs in the case of seasonal cooling demand. On the other hand, if the cooling demand persists throughout the year, as in tropical climates, the combined optimization provides significant benefits, since these savings reach 4.7 % of total costs

Two-stage stochastic programming for the design optimization of district cooling networks under demand and cost uncertainty

The major limitations of district cooling systems are the high capital costs, which make design optimization tools necessary to maximize the potential benefits. Decision makers when designing district cooling have to handle cost and demand uncertainties that further increase the investment risks. On the other hand, the possible evolution of cooling demand during the years, shall be taken into account in the first design stages, in order to allow network expansion in the future. In this paper, a novel two-stage stochastic programming model is therefore proposed for the optimal design of district cooling networks under demand and cost uncertainty. The model was also applied to a case study and the results showed that it is more convenient to build smaller district cooling networks (and eventually enhance them in the future if the cooling demand and electricity costs will increase) rather than building larger systems from the beginning. In addition, it was found that the uncertainties in electricity cost and cooling demand are the ones that most influence the optimal solution. The impact of the stochastic model was evaluated with respect to deterministic approaches, resulting up to 5% less expensive in terms of expected cost and with a three years lower payback time. A second model formulation was also implemented, with more rigid constraints, which limit the amount of pipes that can be installed in a single branch. With this formulation, the model tends to connect more buildings and to install larger pipes from the beginning, but the solution in terms of expected cost is only 0.4% more expensive than the more flexible one. Lastly, it was analysed the impact of asset residual value at the end of project life, revealing that neglecting it would lead to connecting more buildings initially, but in most scenarios the network would not be expanded in the future

Turbinate Surgery in Chronic Rhinosinusitis: Techniques and Ultrastructural Outcomes

Chronic nasal obstruction due to hypertrophic rhinitis is commonly associated with perennial allergic and nonallergic rhinitis. It is not a simple enlargement of mucosal and submucosal tissues, but it is characterized by deep histological modifications. This pathology, a very frequent condition encountered in rhinological practice, has a significant impact on quality of life. Patients usually complain about sneezing, rhinorrhea, frontal headache, postnasal drip, snoring, blocked nasal ducts, and sleep disorders. When medical therapy fails, surgical reduction of inferior turbinates is mandatory. A large variety of surgical techniques in literature exist, but there is a lack of consensus about which is the proper technique to perform. In this chapter, we describe the most important techniques of inferior turbinate reduction with advantages and disadvantages of each one

Bioluminescence Sensing in 3D Spherical Microtissues for Multiple Bioactivity Analysis of Environmental Samples

The development of predictive in vitro sensing tools able to provide rapid information on the different bioactivities of a sample is of pivotal importance, not only to monitor environmental toxicants, but also to understand their mechanisms of action on diverse molecular pathways. This mechanistic understanding is highly important for the characterization of toxicological hazards, and for the risk assessment of chemicals and environmental samples such as surface waters and effluents. Prompted by this need, we developed and optimized a straightforward bioluminescent multiplexed assay which enables the measurement of four bioactivities, selected for their relevance from a toxicological perspective, in bioluminescent microtissues. The assay was developed to monitor inflammatory, antioxidant, and toxic activity, and the presence of heavy metals, and was successfully applied to the analysis of river water samples, showing potential applicability for environmental analyses. The assay, which does not require advanced equipment, can be easily implemented in general laboratories equipped with basic cell culture facilities and a luminometer

Habitat selection and movement by spotted bass and shorthead redhorse downstream of a hydropeaking dam in Missouri

Flow alteration caused by hydropeaking dams may disrupt the natural flow regime and impact physical habitat and biological community, thus threatening the health of freshwater ecosystems. Life history strategies of fish evolved with their environments, including mobility to access habitats for feeding, spawning, refuge, and rearing. However, behavioral responses among species to artificially extreme flow and the influence of spatial and temporal scale, are not clearly understood. We used radio telemetry (from April 2016 to June 2017) to determine the habitat selection and daily and seasonal movement of two native fishes downstream of a hydropeaking dam on the Osage River, Missouri, where river stage may fluctuate up to 5 m daily. We selected two fishes from different habitat and spawning guilds, Spotted Bass (Micropterus punctulatus) and Shorthead Redhorse (Moxostoma macrolepidotum), that are common throughout the Midwestern United States and Canada and represent diverse life history strategies of riverine fishes. We used a Bayesian discrete choice analysis to determine seasonal and flow-related habitat selection and linear regression to evaluate predictors of movement rate of fishes. We determined flow to be "steady" or "fluctuating" based on the range of discharge measured during the 24-hour period prior to a fish location, where the threshold corresponded to minimum or maximum daily discharge being within (steady) or exceeding (fluctuating) 30% of the mean daily flow. Fluctuating flow corresponded to increased movement rate of Spotted Bass and Shorthead Redhorse and selection of slower velocity (1 m/s) during steady flow. Both Spotted Bass and Shorthead Redhorse selected moderate depth (1.5 - 4.0 m) with submerged cover during both steady and fluctuating flow. Spotted Bass movement rate peaked when 3-day average discharge was 500 m3/s, which occurred during consecutive days of hydropeaking or flood management at the dam. This discharge occurred or was exceeded during 25% of the study period, primarily during spring and summer, but did not occur during winter. Smaller adult Spotted Bass had greater movement rates than larger bass, whereas increased movement rate of Shorthead Redhorse was related to increased barometric pressure and Julian day. Both Spotted Bass and Shorthead Redhorse movement rates were greatest during spring (10 - 23[degrees]C) and differed among seasons. The mean longitudinal dispersal by Spotted Bass and Shorthead Redhorse was approximately 20 and 30 rkm, respectively, although 50% and 60% of Spotted Bass and Shorthead Redhorse, respectively, made movements between 5 and 91 rkm from the tagging location. Spotted Bass and Shorthead Redhorse selected similar habitats among steady and fluctuating flow regimes, however, both species responded to flow disturbance by moving more during fluctuating flow than during steady flow, presumably to relocate to suitable habitat. These effects occurred on a short timescale (10 hours to 3 days) and should be could be considered when informing ecologically-sustainable river management in highly flow-altered systems.Includes bibliographical reference

Glucocorticoid receptor signalling activates YAP in breast cancer

The Hippo pathway is an oncosuppressor signalling cascade that plays a major role in the control of cell growth, tissue homoeostasis and organ size. Dysregulation of the Hippo pathway leads to aberrant activation of the transcription co-activator YAP (Yes-associated protein) that contributes to tumorigenesis in several tissues. Here we identify glucocorticoids (GCs) as hormonal activators of YAP. Stimulation of glucocorticoid receptor (GR) leads to increase of YAP protein levels, nuclear accumulation and transcriptional activity in vitro and in vivo. Mechanistically, we find that GCs increase expression and deposition of fibronectin leading to the focal adhesion-Src pathway stimulation, cytoskeleton-dependent YAP activation and expansion of chemoresistant cancer stem cells. GR activation correlates with YAP activity in human breast cancer and predicts bad prognosis in the basal-like subtype. Our results unveil a novel mechanism of YAP activation in cancer and open the possibility to target GR to prevent cancer stem cells self-renewal and chemoresistance

Location-Dependent Human Osteoarthritis Cartilage Response to Realistic Cyclic Loading: Ex-Vivo Analysis on Different Knee Compartments

Objective: Osteoarthritis (OA) is a multifactorial musculoskeletal disorder affecting mostly weight-bearing joints. Chondrocyte response to load is modulated by inflammatory mediators and factors involved in extracellular cartilage matrix (ECM) maintenance, but regulatory mechanisms are not fully clarified yet. By using a recently proposed experimental model combining biomechanical data with cartilage molecular information, basally and following ex-vivo load application, we aimed at improving the understanding of human cartilage response to cyclic mechanical compressive stimuli by including cartilage original anatomical position and OA degree as independent factors. Methods: 19 mono-compartmental Knee OA patients undergoing total knee replacement were recruited. Cartilage explants from four different femoral condyles zones and with different degeneration levels were collected. The response of cartilage samples, pooled according to OA score and anatomical position was tested ex-vivo in a bioreactor. Mechanical stimulation was obtained via a 3-MPa 1-Hz sinusoidal compressive load for 45-min to replicate average knee loading during normal walking. Samples were analysed for chondrocyte gene expression and ECM factor release. Results: Non parametric univariate and multivariate (generalized linear mixed model) analysis was performed to evaluate the effect of compression and IL-1β stimulation in relationship to the anatomical position, local disease severity and clinical parameters with a level of significance set at 0.05. We observed an anti-inflammatory effect of compression inducing a significant downmodulation of IL-6 and IL-8 levels correlated to the anatomical regions, but not to OA score. Moreover, ADAMTS5, PIICP, COMP and CS were upregulated by compression, whereas COL-2CAV was downmodulated, all in relationship to the anatomical position and to the OA degree. Conclusion: While unconfined compression testing may not be fully representative of the in-vivo biomechanical situation, this study demonstrates the importance to consider the original cartilage anatomical position for a reliable biomolecular analysis of knee OA metabolism following mechanical stimulation

Condiciones de vida en las cuencas mineras centrales de Asturias durante la fase expansiva de la revolución industrial asturiana (1885-1907) a través de las Topografías Médicas

En este artículo exponemos las duras condiciones de vida de los obreros minero-metalúrgicos de las cuencas mineras del Nalón y del Caudal-Aller analizando las Topografías Médicas en el momento de expansión de la revolución industrial asturiana. El sistema básico de supervivencia estaba plagado de anomalías que se justifican por el escaso rendimiento fabril debido a los «obreros mixtos». Aspecto que no se pudo resolver con las ayudas empresariales que ofrecía el «pensamiento paternalista»

MiR-23-TrxR1 as a novel molecular axis in skeletal muscle differentiation

Thioredoxin reductase 1 (TrxR1) is a selenocysteine-containing protein involved in cellular redox homeostasis which is downregulated in skeletal muscle differentiation. Here we show that TrxR1 decrease occurring during myogenesis is functionally involved in the coordination of this cellular process. Indeed, TrxR1 depletion reduces myoblasts growth by inducing an early myogenesis -related gene expression pattern which includes myogenin and Myf5 up-regulation and Cyclin D1 decrease. On the contrary, the overexpression of TrxR1 during differentiation delays myogenic process, by negatively affecting the expression of Myogenin and MyHC. Moreover, we found that miR-23a and miR-23b - whose expression was increased in the early stage of C2C12 differentiation - are involved in the regulation of TrxR1 expression through their direct binding to the 3′ UTR of TrxR1 mRNA. Interestingly, the forced inhibition of miR-23a and miR-23b during C2C12 differentiation partially rescues TrxR1 levels and delays the expression of myogenic markers, suggesting the involvement of miR-23 in myogenesis via TrxR1 repression. Taken together, our results depict for the first time a novel molecular axis, which functionally acts in skeletal muscle differentiation through the modulation of TrxR1 by miR-23

Polyamide waste thermal and acoustic properties: experimental and numerical investigation on possible reuse for indoor comfort improvement

Referring to the circular economy model, end-of-life household materials (EoLHM) such as packaging, and clothes, could be converted into building elements – for example panels - with thermal and acoustic properties. Given the high availability almost anywhere, EoLHM represents an alternative to commercial insulating materials that, even though relatively cheap, cannot be afforded by disadvantaged people. The panels are intended for the refurbishment of existing buildings and, therefore, to be installed indoor. This paper presents a multidisciplinary analysis aimed at the characterization of polyamide 6.6 waste from the production of non surgical face masks. The analysis focuses on thermal and acoustic aspects that have determined experimentally by means of the hot plate with guard ring test, and the impedance tube technique respectively. Then, the influence of the panel position on the indoor operative temperature and the reverberation time has been analysed numerically. Results show that, from the thermal and acoustic point of view, this waste is suitable for the realization of building panels and the performance depends on the density and the thickness of the material. However, aspects such as the fire-resistance and the containment of the material need further investigation.Peer ReviewedPostprint (published version