Demand response from thermostatically controlled loads: modelling, control and system-level value

The research area of this thesis concerns the efficient and secure operation of the future low-carbon power system, where alternative sources of control and flexibility will progressively replace the traditional providers of ancillary services i.e. conventional generators. Various options are engaged in this challenge and suit the innovative concept of Smart Grid. Specifically, this thesis investigates the potential of demand side response support by means of thermostatically controlled loads (TCLs). This thesis aims to quantify the impact that a population of thermostatically controlled loads has on the commitment and dispatch of a future power system characterized by a large penetration of renewable energy sources (e.g. wind) that are variable and intermittent. Thanks to their relative insensitivity to temperature fluctuations, thermostatic loads would be able to provide frequency response services and other forms of system services, such as energy arbitrage and congestion relief. These actions in turn enhance the power system operation and support the strict compliance with system security standards. However, the achievement of this transition requires addressing two challenges. The first deals with the design of accurate device models. Significant differences affect the devices’ design included in the same class, leading to different system-level performances. In addition, the flexibility associated to TCLs would be handled more easily by means of models that describes the TCLs dynamics directly as a cluster rather than considering the appliances individually. Second, it is not straightforward achieving satisfactory controllability of a cluster of TCLs for the considered applications. The complexity lies in the typical operation of these devices that has only two power states (on and off) whereas the desired response is continuous. Moreover the control strategy has always to comply with strict device-level temperature constraints as the provision of ancillary services cannot affect the quality of the service of the primary function of TCLs. This thesis addresses the challenges exhibited. Detailed thermal dynamic models are derived for eight classes of domestic and commercial refrigeration units. In addition, a heterogeneous population of TCLs is modelled as a leaky storage unit; this unit describes the aggregate flexibility of a large population of TCLs as a single storage unit incorporating the devices’ physical thermal models and their operational temperature limits. The control problem is solved by means of an initial hybrid controller for frequency response purposes that is afterwards replaced by an advanced controller for various applications. Provided these two elements, a novel demand side response model is designed considering the simultaneous provision of a number of system services and taking into account the effect of the load energy recovery. The model, included in a stochastic scheduling routine, quantifies the system-level operational cost and wind curtailment savings enabled by the TCLs support.Open Acces

Flexible operation of low-inertia power systems connected via high voltage direct current interconnectors

The replacement of conventional synchronous generators with converter-interfaced generation units calls for increased amounts of flexibility. This paper proposes a novel formulation of the security-constrained unit commitment (SCUC) model applied to a multi-area power system connected via High Voltage Direct Current (HVDC) links. From a system perspective, this paper provides a critical analysis of the synergies and differences between the exploitation of thermostatic loads and HVDC links when providing different layers of flexibility to the system. The former units operate within a local dimension, while the latter enable cross-border exchange of flexibility. Eight different ancillary services are modelled to tackle generation/load outages and uncertainty/variability in renewable energy output. The model is applied to the Great Britain network, which is connected to the Irish network and to the one in Continental Europe. Results suggest a critical review of the operation of future low-carbon HVDC-interconnected systems. Feasibility studies on the benefit for interconnection should no longer neglect considerations on local post-fault frequency dynamics in each area of the system. Then, fundamental changes to the mechanisms that price ancillary services become necessary in order to align these mechanisms with the technical needs of the system

The Endless Saga of Monocyte Diversity

Cancer immunotherapy relies on either restoring or activating the function of adaptive immune cells, mainly CD8(+) T lymphocytes. Despite impressive clinical success, cancer immunotherapy remains ineffective in many patients due to the establishment of tumor resistance, largely dependent on the nature of tumor microenvironment. There are several cellular and molecular mechanisms at play, and the goal is to identify those that are clinically significant. Among the hematopoietic-derived cells, monocytes are endowed with high plasticity, responsible for their pro- and anti-tumoral function. Indeed, monocytes are involved in several cancer-associated processes such as immune-tolerance, metastatic spread, neoangiogenesis, and chemotherapy resistance; on the other hand, by presenting cancer-associated antigens, they can also promote and sustain anti-tumoral T cell response. Recently, by high throughput technologies, new findings have revealed previously underappreciated, profound transcriptional, epigenetic, and metabolic differences among monocyte subsets, which complement and expand our knowledge on the monocyte ontogeny, recruitment during steady state, and emergency hematopoiesis, as seen in cancer. The subdivision into discrete monocytes subsets, both in mice and humans, appears an oversimplification, whereas continuum subsets development is best for depicting the real condition. In this review, we examine the evidences sustaining the existence of a monocyte heterogeneity along with functional activities, at the primary tumor and at the metastatic niche. In particular, we describe how tumor-derived soluble factors and cell-cell contact reprogram monocyte function. Finally, we point out the role of monocytes in preparing and shaping the metastatic niche and describe relevant targetable molecules altering monocyte activities. We think that exploiting monocyte complexity can help identifying key pathways important for the treatment of cancer and several conditions where these cells are involved

Clean Colon Software Program (CCSP), Proposal of a standardized Method to quantify Colon Cleansing During Colonoscopy: Preliminary Results

Background and study aims: Neoplastic lesions can be missed during colonoscopy, especially when cleansing is inadequate. Bowel preparation scales have significant limitations and no objective and standardized method currently exists to establish colon cleanliness during colonoscopy. The aims of our study are to create a software algorithm that is able to analyze bowel cleansing during colonoscopies and to compare it to a validate bowel preparation scale. Patients and methods: A software application (the Clean Colon Software Program, CCSP) was developed. Fifty colonoscopies were carried out and video-recorded. Each video was divided into 3 segments: cecum-hepatic flexure (1st Segment), hepatic flexure-descending colon (2nd Segment) and rectosigmoid segment (3rd Segment). Each segment was recorded twice, both before and after careful cleansing of the intestinal wall. A score from 0 (dirty) to 3 (clean) was then assigned by CCSP. All the videos were also viewed by four endoscopists and colon cleansing was established using the Boston Bowel Preparation Scale. Interclass correlation coefficient was then calculated between the endoscopists and the software. Results: The cleansing score of the prelavage colonoscopies was 1.56\ub10.52 and the postlavage one was 2,08\ub10,59 (P<0.001) showing an approximate 33.3% improvement in cleansing after lavage. Right colon segment prelavage (0.99\ub10.69) was dirtier than left colon segment prelavage (2.07\ub10.71). The overall interobserver agreement between the average cleansing score for the 4 endoscopists and the software pre-cleansing was 0.87 (95% CI, 0.84\u20130.90) and post-cleansing was 0.86 (95% CI, 0.83\u20130.89). Conclusions: The software is able to discriminate clean from non-clean colon tracts with high significance and is comparable to endoscopist evaluation

Value of thermostatic loads in energyffirequency response markets:A mean field game approach

This paper studies the distributed coordination of large populations of thermostatically controlled loads (TCLs). It is assumed that each TCL operates in an integrated energy/frequency response market and reacts to broadcast prices in order to minimize its energy cost and, at the same time, maximize its revenues from frequency response. A mean field game is used to model the competing interactions between the TCLs, quantify their impact on the system unit commitment and characterize the desired market equilibrium solution. This approach is then compared with a no-flexibility case in a 2030 scenario of the GB system, assessing the potential benefits of different types of flexible price-responsive TCLs in terms of cost reduction for the individual customers and for the overall system

Redox modulation by plant polyphenols targeting vitagenes for chemoprevention and therapy: Relevance to novel anti-cancer interventions and mini-brain organoid technology

The scientific community, recently, has focused notable attention on the chemopreventive and therapeutic effects of dietary polyphenols for human health. Emerging evidence demonstrates that polyphenols, flavonoids and vitamins counteract and neutralize genetic and environmental stressors, particularly oxidative stress and inflammatory process closely connected to cancer initiation, promotion and progression. Interestingly, polyphenols can exert antioxidant or pro-oxidant cytotoxic effects depending on their endogenous concentration. Notably, polyphenols at high dose act as pro-oxidants in a wide type of cancer cells by inhibiting Nrf2 pathway and the expression of antioxidant vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), GPx, heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system which play an essential role in the metabolism of reactive oxygen species (ROS), detoxification of xenobiotics and inhibition of cancer progression, by inducing apoptosis and cell cycle arrest according to the hormesis approach. Importantly, mutagenesis of Nrf2 pathway can exacerbate its "dark side" role, representing a crucial event in the initiation stage of carcinogenesis. Herein, we review the hormetic effects of polyphenols and nanoincapsulated-polyphenols in chemoprevention and treatment of brain tumors via activation or inhibition of Nrf2/vitagenes to suppress carcinogenesis in the early stages, and thus inhibit its progression. Lastly, we discuss innovative preclinical approaches through mini-brain tumor organoids to study human carcinogenesis, from basic cancer research to clinical practice, as promising tools to recapitulate the arrangement of structural neuronal tissues and biological functions of the human brain, as well as test drug toxicity and drive personalized and precision medicine in brain cancer

A Mean Field Game Approach for Distributed Control of Thermostatic Loads Acting in Simultaneous Energy-Frequency Response Markets

This paper proposes a novel distributed solution for the operation of large populations of thermostatically controlled loads (TCLs) providing frequency support. A game-theory framework is adopted, modeling the TCLs as price-responsive rational agents that schedule their energy consumption and allocate frequency response provision in order to minimize their operational costs. The novelty of this work lies in the use of mean field games to abstract the complex interactions of large numbers of TCLs with the grid and in the introduction of an innovative market structure, envisioning distinct price signals for electricity and response. Differently from previous approaches, such prices are not designed ad hoc but are derived instead from an underlying system scheduling model

La pasión por la lengua: Vincenzo Consolo (homenaje por sus 75 años)

In occasione del 75º compleanno di Vincenzo Consolo, questo libro offre una raccolta monografica degli studi e dei saggi dei più grandi specialisti su Consolo (Renzo Cremante, Giulio Ferroni, Cesare Segre, Salvatore C. Trovato fra gli altri) riunitisi a Valencia nel mese di aprile del 2008, per le Giornate Internazionali di Studio dedicate a Vincenzo Consolo: La pasión por la lengua: Vincenzo Consolo (Homenaje por sus 75 años). Arricchisce il volume il servizio fotografico degli atti accademici

Myoimaging in the NGS era: the discovery of a novel mutation in MYH7 in a family with distal myopathy and core-like features--a case report

Myosin heavy chain 7 related myopathies are rare disorders characterized by a wide phenotypic spectrum and heterogeneous pathological features. In the present study, we performed clinical, morphological, genetic and imaging investigations in three relatives affected by autosomal dominant distal myopathy. Whilst earlier traditional Sanger investigations had pointed to the wrong gene as disease causative, next-generation sequencing allowed us to obtain the definitive molecular genetic diagnosis in the family