48 research outputs found
Control strategy and performance of a small-size thermally integrated Carnot battery based on a Rankine cycle and combined with district heating
To encourage decarbonization and promote a widespread penetration of renewable energy sources in all energy sectors, the development of efficient energy storage systems is essential. Interesting grid-scale electricity storage technologies are the Carnot batteries, whose working principle is based on storing electricity in the form of thermal energy. The charging phase is performed through a heat pump cycle, and the discharging phase is conducted through a heat engine. Since both thermal and electric energy flows are involved, Carnot batteries can be adopted to provide more flexibility in heat and power energy systems. To this aim, efficient scheduling strategies are necessary to manage different energy flows. In this context, this work presents a detailed rule-based control strategy to schedule the synergetic work of a 10-kWe reversible heat pump/organic Rankine cycle Carnot battery integrated to a district heating substation and a photovoltaic power plant, to satisfy a local user's thermal and electric demand. The coupling of a Carnot battery with a district heating substation allows for shaving the thermal demand peaks through the thermal energy stored in the Carnot battery storage, allowing for a downsizing of the district heating substation, with a considerable reduction of the investment costs. Due to the multiplicity of the involved energy flows and the numerous modes of operation, a scheduling logic for the Carnot battery has been developed, to minimize the system operating costs, depending on the boundary conditions. To investigate the influence of the main system design parameters, a detailed and accurate model of the Carnot battery is adopted. Two variants of the reference system, with different heat pump cold source arrangements, are investigated. In the first case, the heat pump absorbs thermal energy from free waste heat. In the second case, the heat pump cold source is the return branch of the district heating substation. The simulation results show that, in the first case, the Carnot battery allows the downsizing of the district heating substation by 47 %, resulting in an annual gain of more than 5000 €. About 70 % of the economic benefit is due to the possibility of reducing the power size of the district heating substation, which can be from 300 to more than 500 kW. The payback period is estimated to be lower than 9 years, while in the second case, the Carnot battery is not able to provide a gain. Eventually, the influence of some parameters, such as the photovoltaic power plant surface, the storage volume, the electricity price profile and the reversible heat pump/organic Rankine cycle specific investment cost, on the techno-economic performance of the system, is investigated through a wide sensitivity analysis. According to the results, the photovoltaic panels surface does not significantly affect the economic gain, while the storage capacity strongly affects the system scheduling and the operating costs. Indeed, it is possible to identify that 13 m3 is the size of the storage volume that minimizes the payback period to 8.22 years, for the considered application. An increase in the electricity price without an increase in the thermal energy price leads to a decrease in economic gain because the benefit brought by the downsizing of district heating is less significant on the economic balance. The specific investment cost of the reversible heat pump/organic Rankine cycle does not influence the operating cost; thus, it does not change the Carnot battery management, nor the economic gain. The specific investment cost affects the payback period, which increases from 8.6 years for a specific cost of 2000 €/kWe to 15.7 years for a specific cost of 5000 €/kWe
Phase I trial combining temozolomide plus lapatinib for the treatment of brain metastases in patients with HER2-positive metastatic breast cancer: the LAPTEM trial
Background Brain metastases (BMs) pose a clinical challenge in breast cancer (BC). Lapatinib or temozolomide showed activity in BM. Our study assessed the combination of both drugs as treatment for patients with HER2-positive BC and BM. Methods Eighteen patients were enrolled, with sixteen of them having recurrent or progressive BM. Any type of previous therapy was allowed, and disease was assessed by gadolinium (Gd)-enhanced magnetic resonance imaging (MRI). The primary end points were the evaluation of the dose-limiting toxicities (DLTs) and the determination of the maximum-tolerated dose (MTD). The secondary end points included objective response rate, clinical benefit and duration of response. Results The lapatinib-temozolomide regimen showed a favorable toxicity profile because the MTD could not be reached. The most common adverse events (AEs) were fatigue, diarrhea and constipation. Disease stabilization was achieved in 10 out of 15 assessable patients. The estimated median survival time for the 16 patients with BM reached 10.94 months (95% CI: 1.09-20.79), whereas the median progression-free survival time was 2.60 months [95% confidence interval (CI): 1.82-3.37]. Conclusions The lapatinib-temozolomide combination is well tolerated. Preliminary evidence of clinical activity was observed in a heavily pretreated population, as indicated by the volumetric reductions occurring in brain lesion
Resilient cooling strategies – A critical review and qualitative assessment
The global effects of climate change will increase the frequency and intensity of extreme events such as heatwaves and power outages, which have consequences for buildings and their cooling systems. Buildings and their cooling systems should be designed and operated to be resilient under such events to protect occupants from potentially dangerous indoor thermal conditions. This study performed a critical review on the state-of-the-art of cooling strategies, with special attention to their performance under heatwaves and power outages. We proposed a definition of resilient cooling and described four criteria for resilience—absorptive capacity, adaptive capacity, restorative capacity, and recovery speed —and used them to qualitatively evaluate the resilience of each strategy. The literature review and qualitative analyses show that to attain resilient cooling, the four resilience criteria should be considered in the design phase of a building or during the planning of retrofits. The building and relevant cooling system characteristics should be considered simultaneously to withstand extreme events. A combination of strategies with different resilience capacities, such as a passive envelope strategy coupled with a low-energy space-cooling solution, may be needed to obtain resilient cooling. Finally, a further direction for a quantitative assessment approach has been pointed out
Inhibition effect of dietary inulin and oligofructose on the growth of transplantable mouse tumor.
BACKGROUND: The influence of 15% inulin or oligofructose incorporated in to the basal diet on the growth of transplantable mouse tumor (TLT) was investigated. MATERIAL AND METHODS: This dietary treatment was performed starting at day 7 before tumor transplantation and continued until the end of observation. The results were evaluated by the mortality rates in the ascitic form of tumor, or by twice weekly solid tumor measurements, with vernier caliper. Mortality rates in ascitic tumors and mean solid tumor surface in these experimental groups was compared with those of animals from control groups fed basal diet without supplementary beta (2-1) fructans. RESULTS: The growth of both forms of transplantable mouse tumors was significantly inhibited by the supplementation of the diet with inulin or oligofructose. CONCLUSION: Such a nontoxic dietary treatment appears to be easily used ad without any risk for patients, and is applicable as an adjuvant factor to classical protocols of human cancer therapy
Advances in imaging head and neck tumours.
The intention of this article is to review the recently published studies summarizing new developments in medical imaging for head and neck tumours.Journal ArticleReviewSCOPUS: re.jinfo:eu-repo/semantics/publishe
Imagerie des tumeurs de la cavité buccale et de l’oropharynx
info:eu-repo/semantics/publishe
Nuclear magnetic resonance: a diagnostic aid in oncology
SCOPUS: ar.jinfo:eu-repo/semantics/publishe
Estimation du profil de la demande énergétique des centres de sante en zones rurales – cas du Bénin
Cet article présente la première partie d'une étude dont l'objectif est de concevoir un système hybride pour des centres de santé ruraux. Il présente l'estimation d'un profil de charge annuel détaillé, estimé à partir d’investigation de plusieurs centres ruraux de santé. Dans la plupart des pays en développement, il y a un manque de données statistiques et d’informations réelles sur la consommation énergétique de la population et des différents types de bâtiments. Ainsi, la méthodologie présentée dans ce travail combine l’enregistrement sur site de la consommation d'électricité, l'estimation statistique des besoins en eau chaude sanitaire (ECS) et la simulation thermique du bâtiment sur TRNSYS 17.Les résultats obtenus permettent de définir un profil détaillé de la charge d'un centre de santé rural avec un pas de temps de 15min à 1 h dont les variations proposent diverses possibilités de scénarios pour l'analyse technicoéconomique. Des informations d'analyses quantitatives et qualitatives sur l'électricité fournie par le réseau sont également présentées.Mots-clés: profil de charge, centre de santé rural, qualité de l’électricité, Trnsys 17, modélisation des bâtiments, coupures d’électricitéEnglish Title: Estimating the energetic load profile of a rural health care centre in rural area of BeninEnglish AbstractThis paper presents the first part of a study which aim is to design a hybrid optimized renewable energy system for rural health care centres supply. It presents the estimation of a detailed yearly load profile estimated from rural centres monitoring. Estimating the demand of energy is an important preliminary step to technico-economic study of hybrid systems. In most developing countries there is a lack of statistical data and retro information on building and population energy consumption. Thus the method presented in this work combined electricity consumption monitoring on site, domestic hot water needs estimation, and thermal building simulations on TRNSYS 17.The obtained results are a detailed profile of the load of a standard rural health care centre with time steps down to 15 min. It shows lots of different variations that while offer various scenarios possibility in technique economic analysis. Quantitative and qualitative analysis information on the grid delivered electricity are also presented.Keywords: Load profile, health centres, grid quality, TRNSYS17, building modelling, load estimation, grid blackout
Progress in magnetic resonance imaging of brain tumours.
Advances in magnetic resonance based techniques have yielded improvements in both high-resolution anatomical imaging and methods to evaluate physiology and function. This review focuses on recent developments in these techniques as applied to pretreatment staging and post-treatment evaluation of brain tumours.Journal ArticleReviewSCOPUS: re.jinfo:eu-repo/semantics/publishe