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Upon aging and exposure to ambient conditions, acrylic colors get dry and the degree of polymerization of the polymer matrix increases due to progressive cross-linking. When interested in studying acrylic colors, separation of the different components, namely matrix, pigments, and fillers, may be particularly useful for their identification and characterization. In the case of aged acrylic colors, as found in artworks themselves or in materials present in artist studios, the separation approaches requiring chemical treatments of fluid samples cannot be applied. To overcome this limit, here a controlled combustion strategy is developed for eliminating the polymer matrix from the color and then recovering a powder made of pigments and fillers, which is analyzed by optical spectroscopy and demonstrated to display the same chromatic/chemical properties of the original color. As a case study, the new method is successfully applied to acrylic colors used by the Italian artist Domenico “Ico” Parisi (1916–1996), found in the original tubes in his studio.

One of the keys for the development of porphyrin-based devices implies that their functionality must be robust and stable against external environmental factors. While the research has been mostly focused on the supramolecular aggregate interactions with target chemicals, the robustness of organic nanostructures in contaminating and even aggressive environments has not been diffusely investigated yet. The results here presented show that crystalline nanowires of meso-tetraphenyl porphyrin (H2TPP) and meso-tetraphenyl porphyrin-Zn(II) (ZnTPP) are insensitive to the exposure to a series of purposely chosen analytes (alcohols, alkanes and amines). Our finding suggests possible applications of the nanowires in organic-based devices (overwhelming the well-known intrinsic weakness of organic electronics), related to material stability through an appropriate material design and the opportunity offered by organic epitaxy.

A planar electromagnetic bandgap configuration of a compact common mode filter that is laid out on printed circuit board is studied. This filter is used to mitigate the common mode noise traveling on high-speed differential signal traces. These differential signal lines may be connected to I/O connectors and cables and small amounts of common mode noise can result in significant electromagnetic emissions. The filter is obtained by a very simple planar geometry based on the electromagnetic bandgap structures. A cavity made by a rectangular/square patch (together with a solid plane underneath) has a well known and predictable resonant behavior; the coupling between the differential pair routed on top of the patterned plane and the patch cavity, occurring when the traces cross the gap between adjacent patches, is used to reduce the energy associated with the propagation of the common mode noise. The properties of this filter are studied taking into account the layout of a real differential microstrip and the number of gap crossings. A compact configuration is proposed. Time domain simulations validate the suggested layout approach.

In this paper, a simple synthesis procedure to design planar electromagnetic bandgap (EBG) structures is proposed. It is based on the consideration of the excess of inductance of a patterned plane with respect to a solid one. The planar EBG structure is sized from the bandgap starting and ending frequencies, and few others specifications employing a closed form formulation. The proposed method is also suitable for the design of embedded planar EBG. The procedure is validated by using measured and numerically computed results.

In this paper, an embedded electromagnetic bandgap structure is proposed for harmonic filtering of differential signal's undesired common mode components. Rather than use lumped circuit components and likely causing some degradation to the intended high speed differential signal, the embedded planar common mode filter causes no degradation to the intended signal, and enhances the signal integrity and electromagnetic compatibility performance of the system. Single ended and differential traces are considered and the impact of the common mode filtering is measured in terms of mixed mode scattering parameters and eye diagram metrics. The systematic procedure to design such a structure is outlined, and its design robustness is also verified.

This paper investigates the relationship among the high-frequency performances of a planar electromagnetic bandgap structure for power integrity applications and its static (dc) behavior. The IR-Drop and the thermal performances are accurately investigated through 3-D simulations. Measurements of the high-frequency electromagnetic properties and of the temperature variation are also performed for validating the models employed in the analysis.

This paper investigates the power integrity behavior of planar electromagnetic bandgap (EBG) structures embedded between two solid layers within the stack-up of a multilayer printed circuit board. The bandgap generation and power integrity performance of the embedded EBG can be achieved only by placing vias shorting the solid planes above and below the patterned layer. The vias inhibit the resonances of the cavity made by the two solid planes, ensuring the designed bandgap, as if the planar EBG was laid out on an outer stack-up layer. The impact of the stitching vias' number and location is addressed and the concepts of regular, global, random, or local via placement are introduced.

Rubrene, perylene,  -quaterthiophene, and tetracene single crystals were grown and placed between indium- tin-oxide and Al electrodes; the current-voltage characteristics of the so-fabricated two-terminal organic devices were measured at ambient conditions under solar simulator illumination. While rubrene single crystals do not exhibit any pho- tovoltaic effect, open-circuit voltages reach values up to 1.8 V in devices based on perylene,  -quaterthiophene, and tetra- cene single crystals.

Porphyrins represent molecular building blocks for the development of a large variety of functional materials. The control of subtle intramolecular and intermolecular processes in solid porphyrin aggregates is promising for the establishment of organic nanotechnology, which requires the knowledge of the properties of nanometric aggregates down to single atoms. Within this framework, the optical anisotropy in thin and ultrathin metal-free tetraphenylporphyrin (H2TPP) films deposited on graphite carries interesting information related to their molecular aggregation. In this work, we compare the surface morphology and the optical anisotropy of H2TPP 2D layers, obtained following a recently developed experimental strategy, with thin films where both 2D and 3D aggregates are present. After reaching a fine control of the relative amount of the two phases present in films of different thicknesses, we propose a precise physical model for the optical response of the pure 2D phase, therefore correlating its optical anisotropy with the electronic properties of single H2TPP molecules, the occurrence of intramolecular chemical reactions, and the molecular arrangement. The response of thicker films, characterized by the coexistence of the 2D and 3D phases, is described by a phenomenological model that considers the main spectroscopic features.

Aim Triple-negative breast cancer (TNBC) is a group of tumors that do not express HER2, estrogen and progesterone receptors. Due to reduced response to conventional antitumor therapies and poor prognosis, new targeted agents are needed for such aggressive sub-type of breast cancer. Multiple lines of evidence support the idea that deregulation of Hedgehog (Hh) signaling has a role in the pathogenesis of breast cancer, in part through the promotion of epithelial-stromal interactions. Therefore, the inhibition of the Hh pathway has been proposed as an interesting therapeutic approach Methods The main objective of this study is to investigate the role of Hh signaling pathway in TNBC. To this aim, we used a panel of human breast cancer cell lines, including five cancer cells lines positive for ER, PR and HER2 expression (nTNBC) and five Triple Negative Breast Cancer cell lines (TNBC). The effects induced by the Smo-inhibitor NVP-LDE225 on proliferation, angiogenesis and signal transduction of breast cancer cells were investigated Results GLI1, one of the major transcription factors induced by Hh signaling activation, is more expressed in TNBC than in nTNBC cell lines. Consistently, NVP-LDE225 treatment induced a more pronounced inhibitory effect on TNBC, in terms of tumor growth: while nTNBC cells display an IC50 of∼5mM, TNBC cell lines are more sensitive, with an average IC50 of∼2mM. In addition, Hh inhibition caused a robust impairment of TNBC cells invasion capabilities. These effects are coupled with a strong inhibition of VEGFA production by both tumor and stromal cells (human fibroblasts and HUVECs). Accordingly, NVP-LDE225 treatment interfered with HUVEC capillary tube formation, an effect even more evident than that observed with bevacizumab, the only targeted agent approved to date for TNBC patients Conclusions Our results suggest that Hh has a specific role in breast epithelial-stromal interactions by regulation of angiogenesis. An orthotopic in vivo experiment in nude mice xenografted with TNBC cells, testing the combination of NVP-LDE225 with bevacizumab, is ongoing Disclosure All authors have declared no conflicts of interest.

The aims of this study is to assess how DPOAEs can discriminate normal subjects with a risk of damage induced by noise, the effectiveness of OAEs in monitoring the effect of Q-Ter, and the role of blood tests to monitor therapy. In the placebo group, the amplitude of DPOAEs was reduced 1 hour and 16 hours after exposure, the group treated with Q-Ter showed normal DPOAEs. This pilot study confirms that DPOAEs represent a sensitive test for monitoring the effects of noise in preclinical conditions and pharmacological treatment.

Aim of this study was to evaluate the effectivness of Coenzyme Q-Ter and Vitamin A in functional voice disorders. Twenty two patients were treated with CoQ10-ter and vitamin A twice a day for ten days. A general otolaryngological/foniatric and logopedic examination were performed. Videolaringostroboscopy, GIRBAS, Voice Handicap Index questionnaire and Multi-Dimensional Voice analysis were carried out before and after treatment. In all patients an improvement was observed in almost all parameters considered after treatment. CoQ10-ter and Vitamin A risulted effective in treatment of patients with functional voice disorders (caused by vocal "malmenage" or "surmenage").

The propagation of the common mode noise on high speed differential traces has an impact on EMI and crosstalk toward nearby traces and electronic devices. A common mode filter, based on a simple planar electromagnetic bandgap, can be easily designed for filtering well-defined harmonics of the propagating common mode signal. The common mode portion of the signal can be reduced through the coupling to the electromagnetic bandgap cavity. This phenomena is obtained at the gap in the reference layer between two adjacent cavities. The electromagnetic principles are introduced and a systematic analysis is carried out in this work investigating the filter performances. The effect of the number of gap crossings on the depth of the filtering band is investigated and a compact layout configuration is introduced for saving layout area.

Clinical and biological prognostic factors in 135 patients affected by sinonasal carcinoma treated in Piedmont. Long-term survival of patients with sinonasal carcinoma remains disappointing in spite of aggressive treatment. The aim of the study is the assessment of overall survival in a group of patients treated with a fixed protocol and the positivity of proliferation and neoangiogenesis markers (Ki-67 and VEGF). From our data it comes out that staging, histological type and treatment are the most important clinical and pathological prognostic factors, moreover surgery +/- radiotherapy is the first line treatment for these tumors. Proliferation index and neoangiogenesis plays a pivotal role in the natural history of such neoplasms.

This paper introduces a compact configuration for a planar EBG-based common mode filter in order to reduce its dimensions in the layout phase of a printed circuit board. The performance of the proposed CM filter is studied both in frequency and time domain by looking at the common mode reduction and the correct propagation of the intentional differential signal. The energy coupling from the common mode signal to the power plane cavity resonant modes can create crosstalk problems on other traces crossing the same gaps. The fundamental mechanisms of this effect are investigated and the crosstalk at the near end and far end are quantified and compared to the ideal case of a solid reference plane.

In this work different physic based equivalent lumped element circuits models representing planar EBG structures are developed. Their results, in terms of evaluation of the lower and upper limits of the bandgap, are compared with a three dimensional simulation considered as reference. Guidelines for the use of these models for their use in planar EBG design are developed.

An experimental validation of an electromagnetic band-gap (EBG) based common mode filter is given in this paper. The proposed layout technique is based on planar EBG structures altered by removing the connecting bridges between adjacent patches. The patches are properly dimensioned for ensuring the presence of frequency notches at the frequencies that should be filtered in the common-mode transfer function. The notch frequency is associated with the first resonant mode of the patch.

This paper presents a new methodology for the transient analysis of nanointerconnects, modeled as lossy and dispersive multiconductor transmission lines. The proposed model is derived from the solution of the Telegrapher's equations in the framework of the Sturm-Liouville theory. The open-ended impedance matrix is expressed in a series form as a sum of infinite rational functions, derived by the series form of the Green's function. Hence, a pole-residue rational model can be synthesized and a reduced-order model to be generated by a simple selection of dominant poles. The spectral form of the Green's function also allows to generate a rational model for the transient voltage sensitivity as well. The numerical results confirm the robustness of the proposed technique and its suitability to be adopted in the design flow of next generation nanointerconnects for signal integrity and electromagnetic compatibility purposes.

The paper studies the signal integrity performances of a microstripline routed over a planar EBG structure. The fundamental mechanisms of the coupling between the signal transmitted along the trace and the resonant properties of the same structure are investigated.

This paper approaches the filtering behavior of Electromagnetic Bandgap (EBG) structures. The transfer function, in terms of S-parameters, of a single ended and a differential microstrip line referenced to an EBG plane are considered: the notches (causing signal attenuation) and flat regions (causing signal propagation) are related to the geometry and characteristics of the EBG structure and can be designed to filter out unwanted harmonic components of the signal. A different EBG-like structure is proposed and its performances analyzed.

This paper presents a new methodology for the transient analysis of nano-interconnects, modeled as lossy and dispersive multiconductor transmission lines. The proposed model is derived from the solution of the Telegrapher's equations in the framework of the Sturm-Liouville theory. The open-ended impedance matrix is expressed in a series form as sum of infinite rational functions, derived by the series form of the Green's function. Hence, a pole-residue rational model can be synthesized and a reduced order model is generated by a simple selection of dominant poles. The numerical results confirm the robustness of the proposed technique.

This study compared the finishes on dental porcelain polished with four different polishing paste systems with oven reglazing and with a porcelain adjustment kit without a polishing paste. The polished/reglazed samples were rated according to quality of finish by independent observers and by scanning electron microscopy. On the basis of visual examination, two of the polishing paste systems tested were found to produce a surface equal to or better than oven glazing. On the basis of SEM examination, oven glazing was found to produce a better surface than the other polishing methods. Not all porcelain polishing systems produce a surface comparable to oven-glazed porcelain, and porcelain polishing systems should be chosen carefully.

Prolonged Q-T interval predicts severe arrhythmias and sudden death, and has been shown to occur in alcoholic liver disease and cirrhotic patients who are candidates for liver transplantation. This study first evaluated the prevalence of prolonged Q-T interval in a large population of unselected patients with cirrhosis, and assessed the relationship between abnormal Q-T, etiology, and severity of liver disease and mortality of patients. Possible causes of Q-T abnormality were also explored. Ninety-four patients with cirrhosis without overt heart disease and 37 control subjects with mild chronic active hepatitis were enrolled. Rate-corrected Q-T interval (Q-Tc) was assessed along with routine liver tests, Child-Pugh score, serum bile salts, electrolytes and creatinine, plasma renin activity, aldosterone, norepinephrine, atrial natriuretic factor and, gonadal hormones. Q-Tc was longer in patients with cirrhosis than in controls (440.3 +/- 3.2 vs. 393.6 +/- 3.7 ms; P.001) and prolonged (440 ms) in 44 patients (46.8%) and 2 controls (5.4%; P.001). Q-Tc length was not influenced by the etiology of cirrhosis and correlated with Child-Pugh score (r = .53; P.001), liver tests such as prothrombin activity, and serum concentrations of albumin and bilirubin, plasma bile salts, and plasma norepinephrine. Multivariate analysis showed that only Child-Pugh score and plasma norepinephrine were independently correlated with Q-Tc duration. Over a median follow-up period of 19 months (range, 2-33 months), patients with Q-Tc longer than 440 ms had a significantly lower survival rate than those with normal Q-Tc. Q-T interval is frequently prolonged in patients with cirrhosis, regardless the etiology of the disease, worsens in parallel with the severity of the disease, and may have an important prognostic meaning. In addition to other undefined factors related to the severity of cirrhosis, sympathoadrenergic hyperactivity may play a pathogenetic role.

OBJECTIVE:\ud We estimated the cost consequence of Italian National Health System (NHS) investment in direct-acting antiviral (DAA) therapy according to hepatitis C virus (HCV) treatment access policies in Italy.\ud \ud METHODS:\ud A multistate, 20-year time horizon Markov model of HCV liver disease progression was developed. Fibrosis stage, age and genotype distributions were derived from the Italian Platform for the Study of Viral Hepatitis Therapies (PITER) cohort. The treatment efficacy, disease progression probabilities and direct costs in each health state were obtained from the literature. The break-even point in time (BPT) was defined as the period of time required for the cumulative costs saved to recover the Italian NHS investment in DAA treatment. Three different PITER enrolment periods, which covered the full DAA access evolution in Italy, were considered.\ud \ud RESULTS:\ud The disease stages of 2657 patients who consecutively underwent DAA therapy from January 2015 to December 2017 at 30 PITER clinical centres were standardized for 1000 patients. The investment in DAAs was considered to equal €25 million, €15 million, and €9 million in 2015, 2016, and 2017, respectively. For patients treated in 2015, the BPT was not achieved, because of the disease severity of the treated patients and high DAA prices. For 2016 and 2017, the estimated BPTs were 6.6 and 6.2 years, respectively. The total cost savings after 20 years were €50.13 and €55.50 million for 1000 patients treated in 2016 and 2017, respectively.\ud \ud CONCLUSIONS:\ud This study may be a useful tool for public decision makers to understand how HCV clinical and epidemiological profiles influence the economic burden of HCV.

Aim: Triple-negative breast cancer (TNBC) is a group of tumors that do not express HER2, estrogen and progesterone receptors. Due to reduced response to conventional antitumor therapies and poor prognosis, new targeted agents are needed for such aggressive sub-type of breast cancer. Multiple lines of evidence support the idea that deregulation of Hedgehog (Hh) signaling has a role in the pathogenesis of breast cancer, in part through the promotion of epithelial-stromal interactions. Therefore, the inhibition of the Hh pathway has been proposed as an interesting therapeutic approach Methods: The main objective of this study is to investigate the role of Hh signaling pathway in TNBC. To this aim, we used a panel of human breast cancer cell lines, including five cancer cells lines positive for ER, PR and HER2 expression (nTNBC) and five Triple Negative Breast Cancer cell lines (TNBC). The effects induced by the Smo-inhibitor NVP-LDE225 on proliferation, angiogenesis and signal transduction of breast cancer cells were investigated Results: GLI1, one of the major transcription factors induced by Hh signaling activation, is more expressed in TNBC than in nTNBC cell lines. Consistently, NVP-LDE225 treatment induced a more pronounced inhibitory effect on TNBC, in terms of tumor growth: while nTNBC cells display an IC50 of∼5mM, TNBC cell lines are more sensitive, with an average IC50 of∼2mM. In addition, Hh inhibition caused a robust impairment of TNBC cells invasion capabilities. These effects are coupled with a strong inhibition of VEGFA production by both tumor and stromal cells (human fibroblasts and HUVECs). Accordingly, NVP-LDE225 treatment interfered with HUVEC capillary tube formation, an effect even more evident than that observed with bevacizumab, the only targeted agent approved to date for TNBC patients Conclusions: Our results suggest that Hh has a specific role in breast epithelial-stromal interactions by regulation of angiogenesis. An orthotopic in vivo experiment in nude mice xenografted with TNBC cells, testing the combination of NVP-LDE225 with bevacizumab, is ongoing Disclosure: All authors have declared no conflicts of interest.

The authors demonstrate amplified spontaneous emission (ASE) from quaterthiophene single crystals and study its behavior at low temperature. The room temperature photoluminescence exhibits line narrowing (spectral width down to 10 nm) at 553 nm for excitation fluence larger than 1 mJ cm(-2). At low temperature (10 K), ASE is observed from two vibronic transitions at 510 nm (0-1) and 553 nm (0-2), with line narrowing down to 5 angstrom, for fluences larger than 100 mu J cm(-2). The stimulated emission cross section is of the order of 10(-15) cm(2), and the ASE is found to be strongly affected by thermally induced dynamic disorder. The emission stability under photopumping is also studied and discussed. (c) 2008 American Institute of Physics.

The authors report on monolithic, light-emitting vertical microcavities based on an organic semiconductor single crystal. The devices are realized by reactive electron-beam deposition of dielectric mirrors and growth of tetracene crystals by physical vapor transport. The microcavities exhibit optical cavity modes in the visible range (550-580 nm) with full width at half maximum down to 2-3 nm, corresponding to a Q factor of about 200, and polarization-induced modal splitting up to 20 meV. These results open perspectives for the realization of polarized-emitting optoelectronic devices based on organic crystals. (c) 2008 American Institute of Physics.

The UV-visible optical spectra of 1,2,3,4-tetrafluoro-7-(N,N)dimethyl-amino-acridine single crystals are reported. The results are discussed on the basis of the molecular transitions and crystal packing in the framework of the theory of molecular excitons under a fluctuating potential field due to dynamic disorder. A strong local geometry distortion is demonstrated by applying the Urbach rule to the absorption tails, which is the amplitude of the local potential fluctuation being larger than the intermolecular transfer energy. The lineshape and linewidth of the emission band and its temperature dependence give further evidence of exciton self-trapping. © 2007 American Institute of Physics.