Publications by authors named "Coli' G"

Background: The proper development of the dental arches, including the eruption and correct positioning of the canines in the arch, is essential for the oral health of growing patients. Impacted canines not only give rise to functional challenges but also pose esthetic issues for patients. The aim of this article is to show if it is possible to benefit from the exclusive use of transparent aligners to guide the eruption of ectopic upper canines into the arch in the correct position.

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Nucleation plays a critical role in the birth of crystals and is associated with a vast array of phenomena, such as protein crystallization and ice formation in clouds. Despite numerous experimental and theoretical studies, many aspects of the nucleation process, such as the polymorph selection mechanism in the early stages, are far from being understood. Here, we show that the hitherto unexplained excess of particles in a face-centered-cubic (fcc)-like environment, as compared to those in a hexagonal-close-packed (hcp)-like environment, in a crystal nucleus of hard spheres can be explained by the higher order structure in the fluid phase.

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Colloidal self-assembly—the spontaneous organization of colloids into ordered structures—has been considered key to produce next-generation materials. However, the present-day staggering variety of colloidal building blocks and the limitless number of thermodynamic conditions make a systematic exploration intractable. The true challenge in this field is to turn this logic around and to develop a robust, versatile algorithm to inverse design colloids that self-assemble into a target structure.

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Colloidal suspensions of two species have the ability to form binary crystals under certain conditions. The hunt for these functional materials and the countless investigations on their formation process are justified by the plethora of synergetic and collective properties these binary superlattices show. Among the many crystal structures observed over the past decades, the highly exotic colloidal AB crystal was predicted to be stable in binary hard-sphere mixtures nearly 30 years ago, yet the kinetic pathway of how homogeneous nucleation occurs in this system is still unknown.

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Using simulations we study the phase behavior of a family of hard spherotetrahedra, a shape that interpolates between tetrahedra and spheres. We identify 13 close-packed structures, some with packings that are significantly denser than previously reported. Twelve of these are crystals with unit cells of = 2 or = 4 particles, but in the shape regime of slightly rounded tetrahedra we find that the densest structure is a quasicrystal approximant with a unit cell of = 82 particles.

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Colloidal crystals with a diamond and pyrochlore structure display wide photonic band gaps at low refractive index contrasts. However, these low-coordinated and open structures are notoriously difficult to self-assemble from colloids interacting with simple pair interactions. To circumvent these problems, one can self-assemble both structures in a closely packed MgCu Laves phase from a binary mixture of colloidal spheres and then selectively remove one of the sublattices.

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We investigate the effect of hydrodynamic interactions (HIs) on the crystal nucleation of hard-sphere colloids for varying supersaturations. We use molecular dynamics and stochastic rotation dynamics techniques to account for the HIs. For high supersaturation values, we perform brute force simulations and compute the nucleation rate, obtaining good agreement with previous studies where HIs were neglected.

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We study the inverse problem of tuning interaction parameters between charged colloidal particles interacting with a hard-core repulsive Yukawa potential, so that they assemble into specified crystal structures. Here, we target the body-centered-cubic (bcc) structure which is only stable in a small region in the phase diagram of charged colloids and is, therefore, challenging to find. In order to achieve this goal, we use the statistical fluctuations in the bond orientational order parameters to tune the interaction parameters for the bcc structure, while initializing the system in the fluid phase, using the Statistical Physics-inspired Inverse Design algorithm.

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There are several possibilities for the prevention of primary, secondary and tertiary osteoporosis but till now they have not been promoted enough and bone fragility is thought about only after the onset of a fracture (tertiary prevention). By recent studies and discoveries it is becoming increasingly clear that there is a relationship between growth and development in early childhood and bone health in old age. Suboptimal bone development leads to a reduction in peak bone mass, and a higher risk of osteoporotic fracture later in life.

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Introduction: clinical guidelines recommend to identify and treat people at high risk of fracture.

Methods: we have carried out a simulation concerning pharmaco-economic issues in the treatment of severe osteoporosis and particularly those people with previous femoral fragility fractures, assuming that only 13.1% of hip fractured patients had started a proper antifracture therapy, as shown by the analysis of the Tuscany regional database.

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Summary: A total of 507,671 people > or =65 experienced hip fractures between 2000 and 2005. In 2005, 94,471 people > or =65 were hospitalized due to hip fractures, corresponding to a 28.5% increase over 6 years.

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Considering that to international level it has put in evidence that often the diagnosis of osteoporosis is underestimated and that diagnostic and therapeutic attention of the same one are often neglected, the authors have assessed the degree of care provided by orthopaedic surgeons about the problem of osteoporosis, considering the medical files of orthopaedics department. Then corrective behaviour were proposed.

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Non bacterial thrombotic endocarditis is a rare disease. The real incidence is not known and seems to range from 0.9 to 9.

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The GSH level in myocardial tissue represents an important defense mechanism against oxygen toxicity. Since the ischemia-induced depletion of GSH might favour the cytotoxicity of oxygen-derived free radicals produced during reperfusion, we assessed the effects of the GSH donor, glutathione monoethylester, in anaesthetized pigs subjected to 90 minutes of coronary occlusion followed by 30 minutes reperfusion. The drug was infused intracoronarily at a dose of 1 mg/ml (0.

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After ligation of the left coronary artery, porcine cardiac mitochondria were isolated by homogenizing the tissue and treating the myofibrillar pellet with nagarse. When compared with unligated controls, the ischemic myocardium showed decreases in phosphocreatine (to 41%), ATP (to 56%) and in the mitochondrial respiratory control index (to 69% and 78% as measured with glutamate and succinate respectively). No changes were found in the corresponding P/O ratios.

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The aim of this study was to investigate the protective efficacy of potassium cardioplegia in general moderate hypothermia, in five pigs, after 90 minutes of myocardial ischemia induced by extracorporeal circulation (ECC) and aortic clamping. The behaviour of subendocardial supply demand ratio (DPTI/TTI), of CSBF (coronary sinus blood flow) and numerous hemodynamic parameters was evaluated in addition to lactate myocardial metabolism changes, at rest, after 90 minutes of total ECC and during a 60 minutes reperfusion period. The reperfusion period included two phases: during the first (15-20 minutes) the animals were in ECC with unclamped aorta; spontaneous circulation was instituted during the second one (40 minutes).

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In our experiments on 5 pigs of weight between 40-50 kg we've noticed changes of the parameters occurring precociously during the initial stage of the shock. Particularly we observed a sudden reduction of diuresis reaching total anuria in 15 min and persistence of this anuria for the entire time of the shock (120 min). Immediately after introduction of the removed blood the arterial pressure and the diuresis return to normal value.

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