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A custom CMOS image sensor designed for catheter based visible and Near-Infra-Red (NIR) endoluminal applications is proposed. The sensor presents high dynamic range (HDR) capability in a controlled light environment, providing a user-programmable power responsivity curve. The fabricated chip is a monochrome imager including a 256 × 256 pixel array, a complete read-out channel, a series of DACs for internal references and digital blocks for chip control. The complete functionality of the chip is guaranteed through six signal pins, used for the I2C-like input interface and the differential analog output. Prototypes were produced using the AMS 0.35 μm OPTO technology. The imager was electrically and optically characterized. Characterization results show state-of-the-art performance in terms of pixel noise (PN <0.6% of the signal swing, worst case), fixed pattern noise (FPN <1.8% of the signal swing, worst case) and signal to noise ratio (SNR 46 dB, worst case), both in the visible and NIR at 850 nm. HDR was characterized till 83.8 dB, limited only by the characterization setup and the chip specific configuration, capability for higher dynamic range has been demonstrated by image acquisition and processing. The chip dimension, the imager noise, and dynamic performance make it suitable for use in endoluminal applications both in the visible and NIR regions. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a development system, based on Field Programmable Gate Array (FPGA), that was specifically designed for testing the entire electronics to be integrated in an endoscopic capsule, such as a camera, an image compression engine, a high-speed telemetric system, illumination and inertial sensors. Thanks to its high flexibility, several features were tested and evaluated, thus allowing to find the optimal configuration, in terms of power consumption, performances and size, to be fit in a capsule. As final result, an average frame rate of 19frame per second (fps) over a transmission channel of 1.5Mbit/s was chosen as the best choice for the development of a miniaturized endoscopic capsule prototype. [Copyright &y& Elsevier]

The article presents research which assessed the chemical vapor deposition of silicon films assisted by flame modeling method. The researchers proposed the simulation of a flame assisted chemical vapor deposition (FACVD) technique in relation to the growth of silicon thin films. They designed the reactor that are able to deposit multicrystalline and micromorphous films at the high growth rates needed for photovoltaic (PV) applications.

Abstract: A prototype of a vision system for capsular endoscopy provided with autofocus function was developed. It is composed by two main parts: a wireless capsule with an adjustable focus in the range between 15mm and 100mm, and a personal computer where the autofocus algorithm is implemented. Several benches and ex vivo tests were performed in order to validate the developed system and encouraging results were obtained. Further miniaturization will be pursued to obtain a swallowable device adequate for capsular endoscopy procedures. [Copyright &y& Elsevier]

Age-related changes of the catecholaminergic nerve fibers of the trachea, bronchial smooth muscle, lung capillaries and bronchus-associated lymphoid tissue (BALT) were studied in male Wistar rats aged 3 months (young), 12 months (adult) and 24 months (old/aged). Catecholamine histo- and immuno-fluorescence techniques were used, associated with image analysis and high pressure liquid chromatography with electrochemical detection of nor-epinephrine (nor-adrenaline). In young rats, blue-green fluorescent nerve fibers supply the trachea-bronchial smooth muscle and tracheal and bronchial glands. These structures are innervated by a delicate network of nerve fibers, being rich in varicosities. Pulmonary capillaries are sparsely innervated. The highest nor-epinephrine concentration was found in the trachea and bronchi, followed by BALT. The density and the pattern of noradrenergic nerve fibers of the trachea-bronchial tree or of the pulmonary vessels were similar in young and adult rats. In aged rats, a loss of noradrenergic nerve fibers, involving primarily the supply to the smooth muscle of the trachea-bronchial tree, was observed. Fluorescence microscopic techniques demonstrated a higher sensitivity than nor-epinephrine assay in detecting changes of the sympathetic nerve supply of the trachea-bronchial tree, pulmonary vessels and BALT. The possible significance of reduced noradrenergic nerve supply of the trachea-bronchial-pulmonary tree in aged rats is discussed. [Copyright &y& Elsevier]

1. The location and distribution of dopaminergic receptors in rat dura mater was studied by examining several dural zones (vascular, perivascular, intervascular) in different cranial and spinal regions. 2. The pharmacological characteristics and anatomical distribution of dopamine D1- and D2-like receptors sites were investigated using combined pharmacological techniques and immunofluorescent microscopy. 3. Samples of rat dura mater were obtained from 10 adult Wistar rats. On frozen slices, dopaminergic D1 and D2 receptors were stained immunohistochemically using monoclonal antibodies. 4. Inhibition studies were performed using fluorescent and non-fluorescent agonists or antagonists to define the pharmacological specificity of the immunostaining. 5. The greater sensitivity to displacement by amisulpride, bromocryptine, domperidone, haloperidol, raclopride and l-sulpiride than to displacement by N-propyl-nor-apomorphine, quinpirole and clozapine suggests that the immunofluorescent sites observed in these experiments are likely to belong to the dopamine D2 receptor subtype. 6. Our observations provide evidence of the presence of D1 and D2 receptors in the wall of meningeal vessels. The dopaminergic receptors are located in the adventitia, media and intima of dural arteries. Furthermore, the density of receptors is higher in close proximity to arteries and decreases passing from the vascular to the perivascular and intervascular zones. 7. In the rat dura mater, dopamine regulates the meningeal blood vessels and, through this action, dopamine and its receptors can play an important role in the pathogenesis of cephalalgia. [ABSTRACT FROM AUTHOR]

The presence and distribution of acetylcholinesterase (AChE) and cholineacetyl transferase activities (Chat) were examined in the bronchusassociated lymphoid tissue (BALT) of juvenile, adult and old rats. Histoenzymatic and immunochemical methods were used in association with quantitative analysis of images and statistical analysis of the data. Our results showed that both AChE and Chat activities were primarily confined to the BALT lymphoid cells. Only a low level of activity was observed in the sub-pleural parenchyma of the lung and in the wall of the bronchus. Moreover, both AChE and Chat activities in the BALT are specifically located in the lymphoid cells. Histoenzymatic staining and corresponding values of quantitative analysis of images confirmed morphological and immunochemical results. Finally, the intensity of histoenzymatic staining for AChE and of immunochemical staining for Chat in BALT of rats strongly decreases with age. On the basis of our results we hypothesize that both AChE and Chat activities may play an important role in BALT and both these enzymes undergo specific age-related changes. [ABSTRACT FROM AUTHOR]

Abstract: The deposition and etching of thin solid films by means of weakly ionized plasmas is discussed here with the aim of stressing the interlink between the involved physical events and their related chemical reactions. This is particularly important in two situations. First in the gas phase, where the concentration, energy, and reactivity of ions, electrons, radicals, and excited molecules generated by electronic reactions influence the electromagnetic field employed to sustain the plasma, the electron energy distribution function, the time evolution and spatial distribution of the electronic temperature and density. Then secondly on the film surface the ionic surface bombardment has a significant impact on the surface chemistry, which eventually determines the film morphology. In this work we report on the progress of theoretical approaches that correctly describe complex systems where chemical and physical aspects are strongly coupled. We show how it is now possible to formulate detailed plasma reactor models that can predict the concentration of the different charged and neutral species in the gas phase, their gas phase and surface reactivity, growth and etch rates, and the film morphological and compositional evolution. The modern approach takes advantage of the progress in computational chemistry and molecular dynamics to calculate the unknown parameters needed as input to the reactor model. Some examples where the mentioned approach is applied are given. [Copyright &y& Elsevier]

Background: Age-related changes of catecholaminergic nerve fibers supplying the myocardium and the coronary vessels were studied in adult and in old rats.Objective: The purpose of this study was to investigate whether there are quantitative changes in myocardial and/or coronary catecholaminergic nerve fibers and related neurotransmitters.Methods: Samples of myocardium and/or coronary vessels were studied by means of glyoxylic acid induced fluorescence, aldehyde-induced fluorescence, and neuropeptide Y immunoreactivity. All morphological results were submitted to quantitative analysis of images. Biochemical dosage of proteins and of norepinephrine was also performed, and morphological data were compared with biochemical ones. Finally, all data were subjected to statistical analysis.Results: Our findings are indicative of an age-related decrease of all types of fluorescent sympathetic nerve fibers in rat heart and coronary arteries. Moreover, our data show that aging induces a strong decrease of norepinephrine levels in tissue homogenates of rat heart and coronary vessels. The majority of the catecholaminergic nerve fibers that show strong age-related changes are not contiguous with contractile cells of myocardium and/or of vascular wall. In fact, these fibers are located in adventitial (or epicardial) and in endothelial (or endocardial) layers.Conclusion: The decrease of the catecholaminergic innervation of heart and coronary vessels of old rats can be in close relationships to the poor cardiac and/or coronary functions observed in old animals. [ABSTRACT FROM AUTHOR]

Summary Age-related changes of the optic nerve were studied in 3-month-old (young), 12-month-old (adult) and 24-month-old (aged) male Sprague–Dawley rats. Cross sections of the intracranial portion of the optic nerves of animals of different age groups were stained with haematoxylin–eosin and examined under a light microscope at low and high magnification. Other sections were stained with crystal violet for demonstration of glial cells. A third group of sections were stained immunohistochemically to detect glial fibrillary acidic protein (GFAP) which is a marker for localizing and characterizing astrocytes. All morphological results were subjected to the quantitative analysis of images and to statistical analysis to identify significant morphometrical data. Tissue protein concentrations were determined on homogenized fragments of optic nerve. Our results demonstrate the following age-related changes: (1) increase of the optic nerve sheaths (meningeal membranes); (2) increased number of astrocytes; (3) increase of areal density of GFAP immunoreactivity; (4) increased diameter and area of the optic nerve; (5) decreased number of nerve fibres; (6) decreased size of nerve fibres and (7) decrease of the nerve fibres/meningeal membrane ratio from 3 : 1 to 1 : 1. Moreover, the protein amount does not change with age. The rat optic nerve, therefore, appears sensitive to ageing processes and can be considered as a useful model for the studies on neuronal ageing. [ABSTRACT FROM AUTHOR]

Interferon, a thymic immunostimulator, was used with the aim of assessing the importance of adrenergic nerve fibers (ANF) and/or AChE-positive nerve fibers (AChENF) in the regulation of some immunological functions in humans. Thymic normal control fragments and/or thymic fragments of immunostimulated patients were removed during surgical biopsies. Thymic slices were stained with eosin-orange (for the recognition of microanatomical details of the microenvironment) and with Bodian''s method for staining of nerve fibers. Histofluorescence microscopy was employed for staining ANF. AChENFs were detected by means of the direct-coloring thiocholine method. All images were submitted to quantitative morphometrical analysis and statistical comparisons of data. Moreover, the amount of proteins and noradrenaline was measured on thymic homogenates of the same patients. Treatment with interferon induces substantial changes in the thymic microenvironment, on ANF, on AChENFs and on the total amount of proteins and noradrenaline in thymic tissue homogenates. In conclusion immunostimulation with interferon induces substantial changes in the whole thymus and in its microenvironment, involving both sympathetic and parasympathetic nerve fibers. [Copyright &y& Elsevier]

Summary A quantitative analysis of peptidergic nerve fibres located in the trabecular meshwork of the guinea pig has been performed. Our results confirm that this structure contains VIP-, NPY- and substance P-like immunoreactivity as major neurotransmitters. These findings were obtained using immunohistochemical techniques. For this purpose serial sections of the eye were stained by immunohistochemistry for each of three neurotransmitters and stained sections were analysed by quantitative image analysis. Our findings demonstrate that SP-positive, NPY-positive and VIP-positive nerve fibres occupy 11.2, 4.9 and 2.4%, respectively, of the observed area (expressed as conventional units, C.U.) in the trabecular meshwork of the guinea pig eye. It is relevant to emphasize that the area containing these three types of peptidergic nerve fibres appears to be large (18.5 ± 6.6 C.U.) in proportion to the total observed area. The innervation of the drainage angle of the guinea pig eye has been well described by many authors. This is the first study to report quantitative measurements of three types of peptidergic nerve fibres identified and measured in this area. The presence of these three neurotransmitters in the trabecular meshwork of guinea pig eye suggests their possible participation in aqueous humor regulation. [ABSTRACT FROM AUTHOR]

Abstract: The mechanisms proposed to explain ACD electroless Ni–P deposition are re-examined and the most important features underlined. Oxidation of hypophosphite on the Ni–P surface is recognized as the rate determining step of the process. The possibility of a bridged intermediate with hypophosphite and hydrolyzed nickel adsorbed at the surface is examined and proved feasible by quantum mechanical calculations. A comparison of electrodeposition and ACD electroless deposition shows that the two processes are anti-correlated, ACD being directly related to the electrolytic hydrogen discharge. Addition of other elements can greatly influence ACD electroless NiP plating process. Metals giving anomalous alloy electrodeposition, such as Zn, Co and Fe behave normally in electroless baths. Elements electrodeposited by induction, such as W and Mo, decrease the P content and the deposition rate. A similar effect occurs for Re, Ce and Cu. Some of the metal stabilizers have also a brightening effect on NiP deposits. This is the case of Cd, Bi, Te and Cu and brightening is related to their interaction with adsorbed hydrogen, stabilized by these additives. [Copyright &y& Elsevier]

Collagen IV and laminin play a key role in regulating stiffness, elasticity and flexibility of the vesico-uterine space (VUS) tissue. The neurotensin (NT), the neuropeptide tyrosine (NPY) and the protein gene product 9.5 (PGP 9.5) possessing vasorelaxation and tissue vascularization activities, play key roles in cervical ripening, scar innervations and pain control. We propose that the integrity of these substances in VUS tissue is compromised after Cesarean section (CS), since wound healing disturbances and pelvic pain, as well as pregnancy and delivery complications, are related with lower uterine segment dysfunctions after CS. Therefore, the contents of collagen IV, laminin, NT, NPY and PGP 9.5 nerve fibres from the VUS tissue samples obtained during the first CS and the repeated CS were comparatively studied. VUS specimens were collected from 104 patients during CS and evaluated by immunohistochemistry. Collagen IV and laminin were mostly found in the vascular membrane bounds and their images were quantitatively evaluated by Quantimet Leica analyzer software. Differences of collagen IV, laminin, NT, NPY and PGP 9.5 values in VUS tissue between the first CS and the repeat CS samples were calculated by Student's /-test. Reduced laminin and increased collagen IV values were observed in the VUS scar tissue after the repeated CS in comparison with those of VUS intact tissue obtained during the first CS. Significantly higher values of nerve fibres, containing NT, NPY and PGP 9.5 were registered in intact VUS tissue samples, respectively 5±0.7, 7±0.6 and 5±0.9 CU, than those of VUS scar tissue samples obtained during the repeated CS, respectively 3±0.6,2±0.4 and 3±0.7 CU (p<0.05). The authors observed increased collagen IV and reduced laminin values after the repeated CS which might be the key signs of inflammatory damage of VUS scar tissue by CS. These findings were strengthened by the registration of decreased NT, NPY and PGP 9.5 values in the same samples, which are important neurotransmitters and are responsible for optimal wound healing, pain control and lower uterine segment functions. [ABSTRACT FROM AUTHOR]

The aim of the present study was to examine whether mast cells have the same variations as the related catecholaminergic nerve fibers. Chemical sympathectomy or surgical removal of right superior cervical ganglion induced a rapid decrease of fluorescence in both nerve fibers and mast cells, as confirmed by quantitative analysis (nerve fibers 19±1.1 vs 1.3±0.6; mast cell 10.8±1.9 vs 2.1±0.3). The results of quantitative analysis after nerve fiber stimulation (electrical), however, showed an increase of the fluorescence in both the nerve fibers and the mast cells (nerve fibers 43.4±2.4; mast cells 18.6±1.6). Moreover, we found that the basal zone is more innervated (regarding catecholaminergic nerve fibers) than the apical one, and that the fluorescence level decreases passing from the vasal zone to the perivasal and intervasal zones, Further studies are needed in order to clarify the role of fluorescent nerve fibers and mast cells of cerebral dura mater in cephalalgia. [ABSTRACT FROM AUTHOR]

Background. The therapeutic management of psoriasis includes conventional treatments as well as the new generation of highly effective TNF-α inhibitors. However, psoriasis has proven to be a complex therapeutic challenge and treatment failures are not uncommon.Thus, laboratory biomarkers of disease progression/therapeutic efficacy may greatly help in the clinical management of psoriasis. Aims. To identify laboratory biomarkers for clinical management and therapeutic monitoring of psoriasis. Methods. An observational study performed on 59 patients, presenting moderate to severe psoriasis, undergoing treatment with anti-TNF-α agents (etanercept, adalimumab, and infliximab). Soluble and cellular immune/inflammatory parameters were assessed at baseline and after 12 and 24weeks of treatment. Results. Clinical efficacy was achieved in 88% of the subjects at 12 weeks, reaching 90% after 24 weeks. IL-6 and IL-22, which were elevated at baseline, were significantly reduced, in association with a significant decrease of CLA+ T cells and an increase of Treg lymphocytes. T, B, and NK cell subsets and T cell response to recall antigens did not show any evidence of immune suppression. Conclusions. Immune/inflammatory parameters including IL-6 and IL-22, CLA+ T cells, and Treg lymphocytes may prove to be valuable laboratory tools for the clinical and therapeutic monitoring of psoriasis. [ABSTRACT FROM AUTHOR]

Abstract: Human thymus of healthy subjects and patients affected by thymoma-associated Myastenia Gravis were studied in order to visualize and compare the morphological distributive pattern of four neuropeptides: vasoactive intestinal peptide, substance P, neuropeptide Y, and neurotensin. Based on our observations, we formulated hypotheses on their relations in neuro-immunomodulation under physiological and pathophysiological conditions. Immuno-histochemical staining for neuropeptides was performed and morphological and morphometrical analyses were conducted on healthy and diseased thymus. In normal thymus, a specific distributive pattern was observed for the several neuropeptide-positive nerves in different thymus lobular zones. In particular substance P-positive fibers were observed in subcapsular zone, specifically located into parenchyma, where they represent the almost total amount of fibers; neurotensin-positive fibers were observed primarily located in parenchyma than perivascular site of several thymus lobular zones, and more abundant the cortico-medullary and medullary zones. Instead VIP- and NPY-positive fibers were widely distributed in perivascular and parenchymal sites of several thymus lobular zones. In thymoma, the distribution of neuropeptide-positive fibers was quantitatively reduced, while cells immunopositive to VIP and substance P were quantitatively increased and dispersed. Observation of the perivascular and parenchymal distribution of the analyzed neuropeptides suggests evidence that a regulatory function is performed by nerves and cells that secrete neuropeptide into the thymus. The alteration of neuropeptide patterns in thymoma suggests that these neurotransmitters play a role in autoimmune diseases such as Myastenia Gravis. [Copyright &y& Elsevier]

Abstract: We have developed a multiscale CVD model in which we coupled consistently the gas phase and surface dynamics. In particular at the macroscale we solve overall mass, momentum, and energy conservation equations with the finite element method, while at the microscale the morphological evolution of the film is investigated with 3D kinetic Monte Carlo. Macro and microscales are linked together imposing continuity of gas phase concentrations and fluxes at the common boundary. The surface model implemented in KMC takes into account the Si(100)2×1 surface reconstruction, and the anisotropic diffusion of H and Si adatoms and dimers. Our simulations show that the diffusion of adsorbed species when most of the surface is covered by hydrogen can hinder the formation of Si dimers, which are favorable Si adsorption sites, affecting the overall growth rate. This indicates that a macroscale model in which an elementary surface kinetic mechanism is implemented cannot predict accurately Si film growth rates at low temperatures, when the surface is mostly covered by adsorbed species. Also, the comparison between experimental and calculated data suggests that a hydrogen desorption mechanism different from the intradimer pathway is active, and that Si adatoms might play a role. [Copyright &y& Elsevier]

Abstract: Silicon is a promising material for solar cells and optical devices. Among the different growth techniques, Plasma Enhanced CVD (PECVD) attracts particular interest allowing to obtain high quality deposition at significant rates and low substrate temperatures. Controlling the film morphology is key for improving the material optoelectronic properties. In order to be able to relate growth rates and quality of the deposited material to the plasma operating conditions we have developed a detailed plasma-reactor model. The solution of mass, momentum and energy conservation equations in a 2D domain is considered, and eventually coupled to the solution of a discharge model based on a simplified gas phase chemistry. The main novelty of this model are the detailed gas phase and surface kinetic schemes developed. The gas phase model comprises about 30 chemical species involved in more than 80 reactions. Surface reaction probabilities were calculated based on a fully atomistic, dynamical approach. The predictive power of the model against experimental data is demonstrated, and the role of various radicals and ions in determining the film growth is discussed. [Copyright &y& Elsevier]

Aim: Early morphological alterations in the rat kidney and heart due to experimentally induced diabetes are described in order to evaluate the possible therapeutic role of low molecular weight heparin (LMWH; OP 2123/parnaparin). Methods: Our findings concern the alterations observed in the rat kidney and heart because these are the organs (together with the retina) mainly involved in the early morphological angiopathic modifications associated with diabetic damage of organs and tissues. In diabetic animals treated with LMWH, the Periodic Acid-Schiff (PAS) reaction showed a slight decrease when compared with the diabetic control group. Photographs were submitted to the quantitative analysis of images using a Quantimet 500 Image Analyzer (Leica) equipped with specific software. The following parameters were measured: (1) total area occupied by alkaline phosphatase (AP)-positive capillaries; (2) number and diameter of AP-positive capillaries; (3) distribution and total area occupied by PAS-positive structures (related to the intensity of the reaction resulting from the different amount of mucopolysaccharides). Results: LMWH treatment is efficient in preventing these modifications, above all in the kidney. The histological study of the heart and kidney shows no significant, relevant alterations. However, the histological study of the mucopolysaccarides in diabetic animals highlighted a tendency for the heart to accumulate these substances. LMWH treatment only modestly reduced this accumulation. Conclusions: Previous evidence demonstrating a beneficial effect of therapy based on heparan sulphate proteoglycans and/or other heparin-like substances in insulin-dependent diabetes mellitus seems to be confirmed by our experimental results in different organs of adult rats. In fact, parnaparin treatment is effective (in our experience) for ameliorating the morphological pattern observed early in some diabetic tissues of rats and, above all, in the kidney. [Copyright &y& Elsevier]

Summary This study points out the early alterations that affect the sciatic nerve of rats with experimentally induced diabetes. It emphasizes the advantages deriving from treatment with low molecular weight heparin (LMWH) OP 2123/parnaparin and correlates these findings with observations emerging from a review of the relevant literature. In fact, the number and diameter of the capillaries within the sciatic nerve of diabetic rats appear to be increased consistent with a microangiopathy (the main characteristic of which is the fragility of new vessels), that is related to the evolution of diabetes in humans and animals. Our results suggest a possible therapeutic role for OP 2123/parnaparin in both diabetic neuropathy and microangiopathy, frequent complications of diabetes. [ABSTRACT FROM AUTHOR]

The role of myosin-like protein in regeneratingand proliferating corneal cells following a standard alkali-injury in therabbit eye has been studied. Microfilaments were observed by conventionaltransmission electron microscopy (T.E.M.) in injured epithelium and in fibroblasts.Typical microfilament bundles with electron dense structures and with stressfibers were evident. The presence of myosin-like proteins was demonstratedby means of immunochemical and autoradiographical techniques. Both epithelialcells and fibroblasts bind antimyosin-like antibodies (AMA). The same cellsstudied with the E.M. showed bundles of microfilaments in the cortical areasof their cytoplasm in correspondence with the same side of fluorescent orlabelled AMA. The immunochemical and ultrastructural results suggest thatboth cells are able to produce in vivo movements involved in morphogeneticphenomena. Therefore, these structures play a role in post-traumatic cornealregeneration. [ABSTRACT FROM AUTHOR]

In this work, we propose a novel data-driven approach for detailed kinetic mechanisms optimization. The approach is founded on a curve matching-based objective function and includes a methodology for the optimisation of pressure-dependent reactions via logarithmic interpolation (PLOG format). In order to highlight the advantages of the new formulation of the objective function, a comparison with L 1 and L 2 norm is performed. The selection of impactful reactions is carried out by introducing a Cumulative Impact Function (CIF), while an Evolutionary Algorithm (EA) is adopted for the optimization. The capabilities of the proposed methodology were demonstrated using a database of ~635 experimental datapoints on ammonia combustion, covering standard targets like ignition delay times, speciation and laminar flame speed. The optimization was carried out starting from a recently published mechanism, describing ammonia pyrolysis and oxidation, largely developed using first-principles calculation of rate constants. After the selection of the 24 most impactful reactions, the related 101 normalized Arrhenius parameters were simultaneously varied, within their uncertainty bounds. Their uncertainty bounds were taken from the literature, when available, or estimated according to the level of theory adopted for the determination of the rate constant. Hence, we also provide guidelines to estimate uncertainty for reaction rate constants derived from first principles calculations using well consolidated computational protocols as a reference. The optimized mechanism was found to improve the nominal one, showing a satisfactory agreement over the entire range of operating conditions. Moreover, the use of 'curve matching' indices was found to outperform the adoption of L 1 and L 2 norms. The comparison between the nominal mechanism and the one optimized via curve matching allowed a clear identification of different critical reaction pathways for different experimental targets. From this perspective, the methodology proposed herein can find further application as a useful design-of-experiments tool for an accurate evaluation of crucial kinetic constants, thus driving further mechanism improvement. [ABSTRACT FROM AUTHOR]

A joint theoretical and experimental analysis of the crystalline fraction in nanocrystalline films grown by low-energy plasma enhanced chemical vapor deposition is presented. The effect of key growth parameters such as temperature, silane flux, and hydrogen dilution ratio is analyzed and modeled at the atomic scale, introducing an environment-dependent crystallization probability. A very good agreement between experiments and theory is found, despite the use of a single fitting parameter. [ABSTRACT FROM AUTHOR]