1,721,010 research outputs found
Leucodistrofia metacromatica: un caso di pubertà precoce
No full textLeucodistrofia metacromatica: un caso di pubertà precoce
Nardecchia F 1
, Poratti E 1
, Dimiccoli P 1
, Di Maggio C 1
, Commone A 1
, Pucci C 1
, Leuzzi V 1
1DAI Neurosc e Sal Ment, Univ Sapienza, Roma
INTRODUZIONE/BACKGROUND: La leucodistrofia metacromatica è una malattia lisosomiale,
autosomica recessiva, caratterizzata
dall'accumulo di solfatidi a livello della mielina del sistema nervoso e, in minor quantità, nei tessuti
a funzione escretoria, tra cui reni, fegato e cistifellea. E’ stato descritto, inoltre, coinvolgimento di
tipo deficitario dell’ipofisi anteriore, surreni, testicoli, ovaie ed endometrio.
METODI / PAZIENTI:Il caso presentato è una bambina di 7,6 anni con esordio tipico intorno ai 2,6
anni, caratterizzato
da rapida regressione psicomotoria e ipotono. La RMN dell’encefalo mostarva diffusa e marcata
iperintensità di segnale della
sostanza bianca biemisferica sovratentoriale, con coinvolgimento del corpo calloso. Il dosaggio dell
dell’attività dell’arilsulfatasi A rivelava una riduzione del 91% e l’indagine genetica una eterozigosi
composta per [p.Tyr201Cys] e [p.Leu428Pro] nel gene ARSA. A 6 mesi dalla diagnosi comparsa di
episodi critici polimorfi. Intorno ai 4 anni osservato telarca
bilaterale isolato e incremento della lanuggine corporea, con successiva comparsa di pubarca.
RISULTATI:Il GnRH test evidenziava un’attivazione dell’asse ipotalamo-ipofisi- gonadi,
definendo un quadro di
pubertà precoce centrale. L’ecografia pelvica mostrava alcuni follicoli bilaterali con diametro di 3
mm. L’Rx polso evidenziava un’età ossea avanzata rispetto a quella cronologica, con uno scarto
superiore ad un anno. La progressione del quadro neurologico ha determinato un quadro di
tetraparesi spastico-distonica, assenza di linguaggio e residuo ed incostante contatto di sguardo.
Assume terapia antiepilettica con crisi plurisettimanali e trattamento ormonale con analoghi del
GnRH.
DISCUSSIONE:A differenza del riscontro di ipofunzionamento dell’asse ipotalamo-ipofisi- gonadi
descritto nelle
leucodistrofie e consensuale al processo degenerativo, si segnala in questo caso l’iperattivazione
dell’asse, finora non descritta in letteratura
Environmental parameters assessment of a new diffuser for air cooling/heating system: Measurements and numerical validation
No full textAir distribution of HVAC systems is the most popular type used in the building sector, having a relevant impact on indoor air quality and occupant wellness. Many types of research developed optimal solutions for the HVAC system’s design, focusing on specific components of the distribution system, on the airflow and geometry of ducts, on the size of ducts, on the shape and position of air diffusers. However, few works in literature proposed a globally experimental and simulation analysis of an air distribution system with a variable mass flaw rate. Along this line, the presented research investigates the potentialities of a new ceiling diffuser, installed in an exhibition room. This system provides a variable mass flow rate thanks to its configuration, providing adequate thermal comfort. A warm wall is chosen as the heating system. Several tests are carried out, six for cooling and two for heating with different volumetric air rates and supply air temperature of the diffusers. The combination of two methods, the measurement campaigns and the computational fluid dynamics (CFD) technique represent a suitable approach to examine the thermal indoor environment. In general, results show a strong capability of this diffuser to provide a uniform temperature and velocity field inside the room. Moreover, experimental and numerical data are significantly comparable with an average deviation of 1% for the velocity and lower 1% for the temperature, guaranteeing an optimal distribution of the understudy environmental parameters on the vertical and horizontal planes
Renewable sources urban cells microgrid. A case study
Full text linkNowadays, microgrid technologies play a relevant role in the research field as well as in the commercial market. The opportunity to provide electricity in wide areas without using centralized electrical infrastructure networks is a reliable key for achieving the European Union sustainability goals. In this regard, the proposed research aims at describing an electric microgrid configuration powered by a photovoltaic system, supplying three school buildings located in the center of Italy. Additionally, the resilience theme is deeply investigated, analyzing the use of an emergency generator system (EGS) in case of electric grid blackouts. MATLAB/Simulink was chosen to simulate the users’ energy demand as well as to calculate the microgrid performance. Results show that almost the total consumption of the microgrid is covered by the photovoltaic system, and the use of an EGS allows energy resilience and moderate economic savings for the communit
Towards the development of a smart district: the application of an holistic planning approach
No full textThe most important challenge for planners and administrations is to identify optimal strategies for improving city life from a global point of view. Urban Planning models should therefore provide solutions in a coordinated and holistic way and should be flexible and adapted to different contexts and territorial levels. Currently, a global approach to the development of Smart Cities is still missing. In this paper the authors developed a planning methodology based on the qualitative and quantitative evaluation of the reciprocal impacts among Smart strategies applied at the district level. The aim is to assess if and to what extent these actions would influence the performance of the district from a global perspective (Economy, Energy, Mobility, Community, Environment)compared to the base case scenario. The methodology has been applied to a sustainable district ideally located in the suburb of Rome and seven Smart scenarios have been modeled and simulated (with Matlab ® - Simulink). Absolute results show the differences among the seven scenarios; the application of the normalized and a-dimensional Smart Performance indicators allowed also to identify the best scenario from a holistic perspective
A New Concept of Direct Oil Cooling System for AFPM Machines, Numerical Analysis and Optimization
Full text linkGiven the strong growth of the electric drive industry, the automotive sector needs to increase the power density of its motors, leading to a size decrease and, consequently, to economic savings. The increase in power density brings with itself the consequence of increasing the Joule effect losses in the active conductors of the machine. For this reason, the problem of cooling turns out to be of utmost importance precisely because of its direct coupling with mechanical and electromagnetic design. This paper has the aim to perform a CFD analysis concerning the cooling system of a permanent magnet axial flux electric machine. The innovative cooling system studied is a direct one which takes advantage of oil to cool down the DC powered coils. The innovation brought by the present research lays in both the direct axial ejection and the use of oil as coolant. At the current state of art, the coolant flows tangentially and, moreover, water is usually employed instead of oil. The main aim of this analysis will be, after a validation of the numerical code by comparison of the literature data, to minimize the maximum temperature of the coil by means of the proper positioning of the nozzle. © 2024 Institute of Physics Publishing. All rights reserved
A review of Italian district heating
No full textDistrict heating is a way to provide heat to residential users, commercial buildings and industrial services, for space heating, hot water and process heat, through a heat distribution network. The distribution system is powered by the heat of one or more sources, such as dedicated heat production systems based on renewable energy and fossil fuels or waste from industrial systems. Large District Heating systems can meet the heat demand of large urban areas and include a range of heat production facilities, transmission pipelines and distribution networks, connecting thousands of consumers. In this review we want to highlight the situation of district heating first at a European level and then at an Italian level, through data on the diffusion, on the heated volume and on the relative costs of this technology
Treatable Inherited Movement Disorders in Children: Spotlight on Clinical and Biochemical Features
Full text linkBackground: About 80% of monogenic metabolic diseases causing movement disorders (MDs) emerges during the first 2 decades of life, and a number of these conditions offers the opportunity of a disease-modifying treatment. The implementation of enlarged neonatal screening programs and the impressive rapid increase of the identification of new conditions are enhancing our potential to recognize and treat several diseases causing MDs, changing their outcome and phenotypic spectrum. Methods and Findings: A literature review of monogenic disorders causing MDs amenable to treatment was conducted focusing on early clinical signs and diagnostic biomarkers. A classification in 3 broad categories based on the therapeutic approach has been proposed. Some disorders result in irreversible neurotoxic lesions that can only be prevented if treated in a presymptomatic stage, and others present with a progressive neurological impairment that a timely diagnosis and treatment may reverse or improve. Some MDs are the result of the failure of intracellular energy supply or altered glucose transport. The treatment in these conditions includes vitamins or a metabolic shift from a carbohydrate to a fatty acid catabolism, respectively. Finally, a group of highly treatable MDs are the result of defects of neurotransmitter metabolism. In these disorders, the supplementation of precursors or mimetics of neurotransmitters can deeply change the disease natural history. Conclusions: To prevent serious and irreversible neurological impairment, the diagnostic work-up of MDs in children should consider a number of clinical red flags and biomarkers denoting specifically treatable diseases
Exergy evaluation of a trigeneration plant applied to industry sector: An Italian case study
No full textNowadays, technology development in the direction of more sustainable energy is imperative. Energy cogeneration and the use of renewable energy sources provide key solutions for reaching these objectives. In situations when seasonal changes in heat demand limit the operation of a full cogeneration system, combined cold-heat-and-power can be employed. To evaluate such energy systems, exergy analysis can be helpful because it can assess the variation in the quality of energy carriers. Among the sectors where exergy assessment is widely applied is the building sector, wherein renewable sources are also used. Some works adopted this kind of exergetic approach also to industries equipped with cogeneration plant. However, few works investigated the opportunity to carry on exergy analysis of a trigeneration system of an industry. Therefore, this paper can give a relevant contribution to this field. The case studies are two Italian industries that, given their physical proximity, want to be an energy community by sharing an internal combustion engine in a trigeneration arrangement. To evaluate the trigeneration systems proposed, exergy analysis was carried out using the Matlab tool. Results underlined that the trigeneration system developed is convenient from the exergy point of view
A review on thermal energy storage
No full textNowadays, there is a huge variety of technologies for storing thermal energy as sensible heat, latent heat, or thermochemical energy at different temperature ranges. In commercial and residential applications, TES systems can significantly increase energy efficiency in industrial processes and avoid the need for further energy supply. TES can store heat in thermal (latent or sensible heat) or chemical ways. This review has the aim to provide a clear explanation of the main TES typologies and their functioning, highlighting each potentiality and weakness. Then, an overview of their implementations in EU countries will be examined. Finally, the forecast in terms of costs and applications of TES will be investigated, giving a complete perspective of this technology
Indoor environmental quality analysis for optimizing energy consumptions varying air ventilation rates
No full textThe energy refurbishment of the existing building heritage is one of the pillars of Italian energy policy. Aiming for energy efficiency and energy saving in end uses, there are wide and diversified improvement strategies, which include interventions on the building envelope and Heating, Ventilation, and Air Conditioning (HVAC) systems, with the introduction of renewable energy sources. The research aims at evaluating the building energy consumptions and Indoor Environmental Quality (IEQ), varying the airflow rates handled by the HVAC system. A Case Study (the Aula Magna of a university building) is analysed; an in-situ monitoring campaign was carried out to evaluate the trend of some environmental parameters that are considered to be significant when varying the external airflow rates handled by the HVAC system. Additionally, dynamic simulations were carried out, with the aim of evaluating the energy savings coming from the airflow rates reduction. The results of this case study highlight the opportunity to achieve significant energy savings, with only slight variations in IEQ; a 50% reduction in airflow rate would decrease energy consumption by up to 45.2%, while increasing the carbon dioxide concentration from 545 ppm to 655 ppm, while the Particulate Matter and Total Volatile Organic Compounds increase is insignificant
- …
