1,437 research outputs found
Pietro Barucci Architetto Autore: Ruggero Lenci Recensione di Luigi Prestinenza Puglisi In: Edilizia e Territorio, 18-23 gennaio 2010, p. 8
No full textPiero Barucci, sulla cui opera e' appena uscita una monografia della Electa curata da Ruggero Lenci, e' stato il protagonista di una lunga stagione dell’architettura italiana, iniziata con il conseguimento della laurea nel luglio del 1946 e completata con la chiusura dello studio nel 2003, dopo oltre cinquanta anni di attività e una quantità impressionante di progetti, soprattutto nel campo dell’edilizia residenziale pubblica. Tra le sue realizzazioni vi sono interventi per il primo (1949-1956) e secondo settennio (1956-1963) del piano Ina Casa. Le numerose opere romane con un quartiere per 412 alloggi a Spinaceto (1966), edifici di edilizia sperimentale al Tiburtino sud (1971), il quartiere Torrevecchia (1978), comparti abitativi a Tor Bella Monaca (1980) e il quartiere Quartaccio (1984). E poi numerosi piani di edilizia residenziale e servizi a Napoli, a seguito del terremoto del 1980.
Il lavoro per il quale Barucci e' più famoso, e' il più controverso. Si tratta del quartiere romano Laurentino 38. E’, infatti, additato da molti come uno dei mostri edilizi realizzati nella capitale a partire dagli anni settanta insieme con il Corviale di Mario Fiorentino e Vigne Nuove di Lucio Passarelli. E fa parte di un girone più ampio di dannati che include il quartiere Zen di Vittorio Gregotti a Palermo.
A rendere celebre il Laurentino ha contribuito la vicenda dei ponti, cioè le attrezzature destinate a servizi che avrebbero dovuto caratterizzare il nuovo quartiere. L’idea che portò alla loro invenzione era costruire un lungo anello stradale punteggiato da una decina di corposi nuclei residenziali ciascuno dei quali, a sua volta, si poneva a cavallo di questo anello stradale grazie a un ponte destinato ai servizi. Ogni ponte serviva quindi il nucleo residenziale di sua competenza, ma tutti insieme, posti in sequenza lungo la strada, vertebravano lo spazio pubblico del quartiere.
I ponti non funzionarono mai. Furono subito occupati e trasformati in abitazioni precarie, diventando oltretutto, a causa delle provenienze sociali degli occupanti, luoghi degradati e pericolosi. E il fulcro funzionale e simbolico del quartiere che avrebbe dovuto attrarre gli abitanti inducendoli alla socialità, divenne proprio il luogo che li repelleva. La storia, come succede per tutte le vicende in cui sono coinvolti soggetti pubblici, si trascinò penosamente per anni, finchè non si decise di intervenire nel più semplice e quindi nel peggiore dei modi. Abbattendo alcuni ponti e snaturando il quartiere, che adesso ha perso le caratteristiche originarie ma non ha acquistato quelle di un insediamento alternativo credibile.
La vicenda del Laurentino rappresenta una ferita ancora aperta all’interno della cultura architettonica nazionale. Lo testimoniano anche i testi a corredo del libro, firmati da Ruggero Lenci, Leonardo Benevolo, Alessandra Muntuoni, Giorgio Muratore e Franco Purini. Mette in luce, infatti, la distanza che esiste tra la teoria e la pratica, tra ciò che agli occhi degli architetti appare come progressista e ciò che effettivamente si dimostra come tale.
A volte occorrono anni perché un edificio o un quartiere innovativo possa essere capito dai propri abitanti e si sviluppino le forme di gestione degli spazi previste dai loro ideatori. Così e' successo, per esempio, all’Unità di abitazione di Le Corbusier di Marsiglia che ha cominciato a funzionare solo dal momento in cui si e' trasformata in un condominio rigidamente organizzato oppure al quartiere Olimpico a Roma che dopo anni di penoso degrado, e' tra i più appetibili della capitale, grazie anche alla realizzazione del vicino auditorium disegnato da Renzo Piano.
Ma molte volte, il tempo non basta. Mi sembra difficile che il Corviale, lo Zen o Vigne Nuove possano essere mai redenti da un uso virtuoso.
Sarà questa la sorte del Laurentino e di altri progetti di edilizia residenziale pubblica disegnati da Barucci? Non saprei francamente rispondere. A guardarli adesso, molti piani disegnati tra gli anni settanta e ottanta sembrano datati e legati a una stagione in cui la necessità economica e l’ideologia non sempre contribuirono a realizzare una città nella quale avremmo piacere a vivere. Tuttavia, come mostrano le pagine del libro, corposo e ricchissimo di informazioni,i complessi di Barucci si caratterizzano per una cura, un’intelligenza tecnologica e un’attenzione progettuale che non si può liquidare sbrigativamente.
Prova ne sia che in altri progetti, dove l’ansia dei costi e dei tempi, e soprattutto la pressione dell’ideologia, non erano così incalzanti, Barucci ha realizzato opere più memorabili. Penso per esempio al centro direzionale di Piazzale Caravaggio a Roma (1962), che, come ha notato giustamente Alessandra Muntoni, e' ancora oggi una delle poche, grandi e dignitose opere di architettura contemporanea della Capitale.
Ruggero Lenci, Piero Barucci Architetto, Electa, Milano 2009. Pagg.392. Testi di: Piero Barucci, Leonardo Benevolo, Alessandra Muntoni, Giorgio Muratore, Franco Purin
Altered neurogenic and mechanical responses to acetylcholine, ATP and substance P in detrusor from rat with outlet obstruction
No full textThe well-known side effects of anticholinergic compounds used to treat urinary incontinence caused by detrusor overactivity have addressed the interest on other pharmacological intervention. The purpose of the present work was to investigate the possible changes in purinergic and cholinergic components of parasympathetic neurotransmission in obstructed rat bladders with detrusor overactivity, and to examine the effect of the association of suramin, atropine and indomethacin on nerve-mediated responses to electrical field stimulation (EFS). Mechanical responses to exogenous acetylcholine, ATP and substance P were also evaluated. Altered sensitivities to acetylcholine and to the sensory neurotransmitter substance P, but unchanged sensitivity to the stable ATP analogue alpha,beta-methyleneATP were observed in bladders from obstructed rats. Suramin and atropine inhibited purinergic and cholinergic components of the neurogenic responses evoked by EFS in detrusor strips from control and obstructed rats. Interestingly, suramin enhanced the antagonistic effect of atropine on neurogenic responses of detrusor strips at all frequencies of stimulation tested. Our results suggest that the association between an antimuscarinic drug and an antagonist of P2X purinoceptors such as suramin might be helpful to reduce the therapeutic dosage of the antimuscarinic drug, along with its side effects. This approach may be of interest in the therapy of patients with bladder incontinence caused by detrusor overactivity, which do not even respond to a maximal dosage of antimuscarinic dru
Didattica e Architettura – Tesi in composizione architettonica Autore: Ruggero Lenci Recensione di Luigi Prestinenza Puglisi In: Edilizia e Territorio, n. 10, 2008, p. 3
No full text
EFFECT OF SUBSTANCE-P AND CAPSAICIN ON STOMACH FUNDUS AND ILEUM OF STREPTOZOTOCIN-DIABETIC RATS
No full textThe in vitro responses of longitudinal preparations of rat stomach fundus and ileum to capsaicin at 1, 8, 4, 16 and 26 weeks and to substance P at 1 and 8 weeks from diabetes induction were studied. The results were compared with those obtained in age-matched control rats. The contractile responses to exogenous substance P and capsaicin were not affected in the stomach fundus from diabetic rats. Atropine (1 microM) did not antagonize the substance P-induced response whereas it inhibited about 90% of the capsaicin-induced response in controls and about 60% of the response in diabetic rats. At the resting tone, capsaicin induced a relaxation followed by a contraction in stomach fundus of control rats. Only a contraction was evoked in diabetic rats. In carbachol (0.05-0.1 microM) pre-stimulated strips, a complete restoration of the biphasic response was obtained in the diabetic state. The contractile response elicited by exogenous substance P was not significantly increased in the ileum preparations from diabetic rats; nevertheless the EC50 value for substance P was reduced 8 weeks after the onset of diabetes. The response elicited by capsaicin in the ileum of control rats was also biphasic. The capsaicin-induced contraction was greater in tissue from diabetic rats as compared with controls and relaxation was not evident. An age-related decrease of the contraction was also evident in both groups. Atropine (1 microM) partially antagonized the responses to substance P and capsaicin. The inhibition of the responses with atropine was more evident in control than in diabetic rats. These results suggest that the myogenic actions of several agonists in these two tissues are differently modified in experimental diabetes
EFFECT OF SUBSTANCE-P AND CAPSAICIN ON URINARY-BLADDER OF DIABETIC RATS AND THE ROLE OF THE EPITHELIUM
No full textThe in vitro responses of rat urinary bladder, to substance P and capsaicin were studied at 1, 4, 16, and 26 weeks of diabetes induction by streptozotocin. We also studied the role of epithelium in these responses. The results were compared with those obtained in age-matched control rats. The bladder contractile response to exogenous substance P was similar in both groups at all stages (1-26 weeks) studied, whereas the bladder response to capsaicin gradually decreased with the progression of diabetes. Atropine did not inhibit these responses whereas indomethacin slightly reduced substance P- but not capsaicin-induced responses in control and diabetic rats. The removal of epithelium slightly increased the substance P- and capsaicin-induced responses in control tissue; these responses were significantly reduced in tissue excised from diabetic rats. Our results indicate that, in rat urinary bladder, diabetes (1) provokes an impairment of capsaicin-sensitive sensory fibers but not of the cholinergic system even at an early stage (4 weeks) of the disease, (2) has no effect on the sensitivity of smooth muscle cells to substance P, (3) stimulates the release of epithelial contracting factors, partially non-prostanoic. Furthermore epithelium removal impairs acetylcholine-induced contraction in bladder excised from diabetic rats but not in controls
Mixed-Mode Stress in Silicon-Germanium Heterostructure Bipolar Transistors: Insights from Experiments and Simulations
No full textRecently, a wide class of market segments (e.g., health, material science, security, and communications) is tackled by circuits fabricated in BiCMOS technology, integrating silicon-germanium (SiGe) heterojunction bipolar transistors (HBTs) and passives. Currently, the reliability of SiGe HBT devices is a major concern, and much attention is given to self-heating (SH), that limits device performance and regulates their degradation during stress. Moreover, its relevance is supposed to increase with device scaling. In this paper, we explore the reliability issues of SiGe HBTs by combining dedicated experiments and TCAD simulations. We develop and calibrate a TCAD model that is then used to investigate SH effects in both operating and stress conditions. Results show the important role played by the back-end-of-line (BEOL) and by the substrate thermal resistance in dissipating the heat generated by impact ionization. The location at which defects are generated during stress and the microscopic properties of the defects are determined experimentally by means of dedicated noise measurements. Including defects in the TCAD model allows reproducing the degradation observed in stress experiments. Simulations of the SH effects on a stressed device in measurement conditions revealed the presence of a hole hot spot that suggests a possible physical mechanism involved in the degradation slowdown at long stress times reported in the literature
Combining Experiments and a Novel Small Signal Model to Investigate the Degradation Mechanisms in Ferroelectric Tunnel Junctions
No full textSustainable Rural Buildings for Implementing the Agroecology Concept at Territorial and Landscape Level in the Mediterranean Area
No full textAgroecology is a strategy aimed to combine technical, ecological and social principles, to design and manage agro-food systems, while protecting biodi-versity, promoting soil health and optimizing resource management. This approach maximizes relationships among humans, animals, and plants within their natural environment, addressing global food demands, while minimizing the environ-mental footprint of agricultural activities. Fostering agroecology at territorial and landscape level offers a holistic approach to sustainable development, combining technical, social, political, economic, and cultural factors with local realities. In this framework, Agricultural and Biosystem Engineering may play a decisive role, particularly thanks to its contribution to the analysis and exploitation of:
-) Natural materials for farm buildings-such as wood, stone, as well as natural fibers (wool, straw, reed, hemp, etc.), and recycled waste biomass, improving mechanical and thermal characteristics of building components and introducing new bio-based materials.
-) New technologies for land survey, planning and management-includ-ing digital tools, remote-sensed data, Geographical Information Systems, Internet of Things (IoT), etc., able to optimize crop management, while also reducing chemical inputs and natural resource consumption.
This review paper presents the advancement of research and study activities on Agricultural and Biosystems Engineering and their contribution to the imple-mentation of the Agroecology concept, aimed to increase the sustainability of agricultural activities, thanks to the implementation of new specific study courses as well as whole curricula, while opening new prospects of development for the scientific community
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