1,722,011 research outputs found
Ballota Nigra
No full textGenetic Architectures and Computation
With the convergence of computation and biogenetics in the latter part of the 20th century and subsequent completion of the human genome project, we are now witnessing the emergence of a post-human era, which will transform the way we think and interact with the world at large.
http://geneticarchitectures.blogspot.com - blog incipit
Nella sua definizione storica l’architettura (arché, principio primo + tektòn, costruire o costruttore) è l’arte di costruire secondo i principi primi (o leggi universali). Con la convergenza tra biogenetica e computazione in architettura, le definizioni basilari necessitano un ripensamento e una nuova definizione alla luce della nostra coscienza della complessità. L’architettura diviene quindi “la costruzione generativa di mondi possibili” (Karl S. Chu). Forma, contenuto, tempo, spazio sono concetti che necessitano una ridefinizione alla luce di modificazioni possibili dalla nano alla giga scala. Il computer, inteso come macchina astratta (a partire dalla concettualizzazione che Alan Turing ne fece nel 1936), è il paradigma di lettura della realtà. Quantum computing, black hole computing e DNA computing sono realtà che stanno sulla soglia tra futuro prossimo e presente, pronte a entrare nel nostro quotidiano quanto prima. Considerando che il nostro DNA è costituito da combinazioni e permutazioni degli stessi 4 elementi che formano tutti gli altri esseri viventi, noi stessi potremmo diventare una forma di computazione (il recente completamento dello Human Genome Project ne è una interessante premessa). Secondo Stephen Wolfram, l’universo è una forma di computazione. L’assunto, provocatorio certo, ma anche profondo in quanto possibilità di riflessione, è uno dei punti di partenza, oltre alla Macchina Universale di Turing (UTM, lo schema teorico di tutti i computer) di questo studio. Oltre ad una definizione di una teoria Computazionale dell’architettura, si esplorano i sistemi di crescita e formazione del mondo biologico, per poi riprodurre quei sistemi in forma logica (sistema formale) e quindi in superfici e spazio (sistema di mapping). I sistemi biologici sono costituiti da algoritmi e patterns. La biomimetica studia il prodotto finito di un sistema altamente sofisticato di crescita ed evoluzione, ma da un punto di vista puramente esogeno, esterno al sistema. In questo studio sono invece indagati i processi endogeni comuni a tutti i sistemi biologici.
Attraverso lo studio di sistemi auto replicanti, con algoritmi di sostituzione e algoritmi a matrice sono stati generati pattern da cui poi si sono ricavate superfici e spazi, non progettati in senso tradizionale del termine, ma progettati in quanto l’equazione generativa lo è stata, mentre le forme (forms and shapes) sono il derivato del processo di crescita e del sistema di mapping scelto per tradurre in spazi il sistema formale. In questo caso ci si è limitati a semplici studi in cui non ci sono alterazioni delle leggi, nè fattore tempo e alle lettere a,b e c non corrispondevano altro che coordinate o operazioni basiche di modellazione in sistemi di mappatura, ma si può anche far corrispondere alle stesse lettere equazioni complesse e, complicando le regole in modo da stabilire non regole generali per il sistema, ma rapporti locali distinti (ad esempio attraverso regole di vicinanza) e che possono dare risultati inattesi, fino a simulare un sistema emergente
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No full textFlower store project
Entomophilous flowers need insects to perform reproduction (through pollination), basing their reproductive potential on attraction. Beauty then performs an essential function.
Analyzing the properties of the Cyclamen Graecum, we investigated the particular conditions of petals - the main tool through which the flower signals its presence to insects. In the Cyclamen petals bend upward, creating a very interesting topological condition around the corolla: their plication creates a continuous passage from outer to inner surface, just like some topological surfaces such as the Klein Bottle. Exploring this condition under TopMod® (along with the concepts of involution, gastrulation and with the translucency and color properties of the petals) we tried to avoid a mere biomorphic translation, going more into the generative process driven by the program
Effects of the Transverse Curvature on the Statistics of Fully Developed Turbulent Flow in an Annular Pipe
No full textDesign optimization of a special relief valve with response surface methodology
No full textThis paper describes the utilize of a numerical procedure for the analysis and the optimization of an hydraulic component, namely a particular direct acting relief and anti-cavitation cartridge valve. The element taken as reference is usually connected to a hydraulic line with the aim of keeping the circuit pressure between two different set values; moreover it can work as anti-shock valve, avoiding pressure peaks.
The developed procedure is based on Response Surface Methodology techniques, adopting the path search method known as Steepest Descent. For this purpose, the valve behaviour is analytically described by means of a properly defined objective function. The procedure approximates this objective function with a simple model whose coefficients are evaluated using the predictions performed by a AMESim® model of the valve, developed in C++ language by the authors. The sets of simulations for the fitting model are planned according to Design Of Experiments techniques. The entire optimization algorithm has been developed with MATLAB® scripts, which are able to plan the simulation with the AMESim® model of the valve, automatically execute the simulations, post process the results and finally establish the optimal configuration of the component taken as reference.
The considered starting point for the optimization process is given by a stock configurations of the valve, considered also for the experimental validation of the AMESIM® model in previous works. Three different optimal configurations of the valve, for different values of the preset pressure, have been proposed, and prototypes of the new designs have been realized. Experimental investigations point out the improved performance of the proposed designs, highlighting the potentials of the developed optimization methodology
Bone marrow stromal cells-induced drug resistance in multiple myeloma
No full textMultiple myeloma is a B-cell lineage cancer in which neoplastic plasma cells expand in the bone marrow and pathophysiological interactions with components of microenvironment influence many biological aspects of the malignant phenotype, including apoptosis, survival, proliferation, and invasion. Despite the therapeutic progress achieved in the last two decades with the introduction of a more effective and safe new class of drugs (i.e., immunomodulators, proteasome inhibitors, monoclonal antibodies), there is improvement in patient survival, and multiple myeloma (MM) remains a non-curable disease. The bone marrow microenvironment is a complex structure composed of cells, extracellular matrix (ECM) proteins, and cytokines, in which tumor plasma cells home and expand. The role of the bone marrow (BM) microenvironment is fundamental during MM disease progression because modification induced by tumor plasma cells is crucial for composing a “permissive” environment that supports MM plasma cells proliferation, migration, survival, and drug resistance. The “activated phenotype” of the microenvironment of multiple myeloma is functional to plasma cell proliferation and spreading and to plasma cell drug resistance. Plasma cell drug resistance induced by bone marrow stromal cells is mediated by stress-managing pathways, autophagy, transcriptional rewiring, and non-coding RNAs dysregulation. These processes represent novel targets for the ever-increasing anti-MM therapeutic armamentarium
A Potential Formulation on Non-Linear Model of Flow through Anisotropic Porous Media
No full textA theoretical analysis, based on the search for a normal dissipation potential, is performed in order to generalize the empirical non-Darcy one-dimensional flow models to 3-D flows through anisotropic porous media. In an abstract framework, it is proven that a large number of heuristic nonlinear equations governing the multidimensional flow through isotropic porous media can be derived starting from a potential strictly related to the mechanical power dissipated by the fluid. Such a formulation allows to define, for the tensor permeability case, a wide class of filtration models according to the Onsager’s generalized theory of dissipative mechanical systems. A consistent generalization to anisotropic permeability case of polynomial flow models is proposed. Both primal and dual mixed variational formulations associated to the proposed quadratic and incomplete cubic flow models are introduced and discussed
Instabilities of a shear-thinning fluid falling over an undulating porous layer
No full textWe investigate the stability of a fluid film with power-law rheology flowing down a porous nonplanar incline with periodic undulations. A model is implemented which accounts for filtration flow through the substrate. A reduction in dimensionality in the model is achieved by exploiting the assumed thinness of the liquid film relative to the wavelength of the bottom undulations. A steady flow is obtained and its linear stability determined through the application of Floquet–Bloch theory. A nonlinear stability analysis is also carried out by calculating the evolution of the perturbed steady flow by means of numerical simulations
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