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Background: Both cardiovascular and complement-mediated disorders might lead to microvascular damages in anti-neutrophil cytoplasm autoantibodies (ANCA)-associated vasculitides (AAV). We aimed at investigating, for the first time, subclinical microvascular abnormalities with non-invasive techniques in AAV patients by analyzing both retinal and nailfold capillary changes. Retinal plexi were investigated using optical coherence tomography angiography (OCT-A), while nailfold capillary changes by video-capillaroscopy (NVC). Potential correlations between microvessels' abnormalities and disease damage were also explored. Methods: An observational study was conducted on consecutive patients who met the inclusion criteria of defined diagnosis of eosinophilic granulomatosis with polyangiitis (EGPA), granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA), age ≥ 18 ≤ 75 yrs, and no ophthalmological disorders. Disease activity was assessed by Birmingham Vasculitis Activity Score (BVAS), damage by Vasculitis Damage Index (VDI), and poorer prognosis by the Five Factor Score (FFS). Quantitative analysis of vessel density (VD) was performed by OCT-A in both superficial and deep capillary plexi. Figures and detailed analysis from NVC were performed for all subjects in the study. Results: Included AAV patients (n = 23) were compared with 20 age/sex-matched healthy controls (HC). Retinal VD in superficial whole and parafoveal plexi resulted significantly decreased in AAV compared to HC (P = 0.02 and P = 0.01, respectively). Furthermore, deep whole and parafoveal vessel density was strongly reduced in AAV than HC (P ≤ 0.0001 for both). In AAV patients, significant inverse correlations occurred between VDI and OCTA-VD in both superficial (parafoveal, P = 0.03) and deep plexi (whole, P = 0.003, and parafoveal P = 0.02). Non-specific NVC pattern abnormalities occurred in 82% of AAV patients with a similar prevalence (75%) in HC. In AAV, common abnormalities were edema and tortuosity in a comparable distribution with HC. Correlations between NVC changes and OCT-A abnormalities have not been described. Conclusion: Subclinical microvascular retinal changes occur in patients with AAV and correlate with the disease-related damage. In this context, the OCT-A can represent a useful tool in the early detection of vascular damage. AAV patients present microvascular abnormalities at NVC, whose clinical relevance requires further studies. [ABSTRACT FROM AUTHOR]

This paper analyzes the influence of the radial electric field radiated by return strokes on the lightning performance of an overhead distribution line. The calculation of the lightning electromagnetic pulse (LEMP) over a finitely conducting ground is performed by solving the Sommerfeld integral for the radial component of the electric field. The proposed method uses a trapezoidal scheme in which nodes are equidistant in logarithmic scale. The method is implemented in the LIOV-EMTP (lightning induced overvoltages-electromagnetic transient program) code that solves the field-to-multiconductor line coupling equations and calculates the lightning induced voltages in distribution networks having complex and realistic configuration. The results obtained by the proposed method for the LEMP calculation are compared with those obtained by using the Cooray–Rubinstein formula, which is the most commonly adopted approximation. Finally, the peak-amplitude probability distributions of the induced voltages obtained by using the two approaches are presented. It is shown that for ground conductivity values larger than 0.001 S/m, the Cooray–Rubinstein formula provides results in agreement with the accurate solution, while it significantly underestimates the lightning performance for lower conductivities and for lines with a high insulation level. [ABSTRACT FROM AUTHOR]

An accurate evaluation of the lightning performance of overhead power distribution lines, that is, the evaluation of the expected number of annual flashovers, can be obtained by the application of the Monte Carlo method. In order to reduce the computational effort, a simplified waveform of the channel base current is generally assumed, for example, a linearly rising current with flat top. This paper proposes a Monte Carlo approach able to take into account the typical functions adopted to represent the waveform of the lightning current at the channel base (i.e., the Heidler function and the CIGRÉ function). Moreover, this paper analyzes the effects of different current waveforms on the lightning performance of distribution lines for both direct and indirect strokes. [ABSTRACT FROM AUTHOR]

This paper presents a one-dimensional model for the transient liquid flow (without cavitation) in constant diameter pipes. The system equations, which describe the macroscopic thermo-mechanical behavior of the pipe-flow system, are obtained within the framework of the continuum mechanics and classical thermodynamics. The flow problem is formulated as an inverse problem. Experimental data, concerning the propagation of pressure waves in liquid-filled pipes, are used to infer the parameters that characterize the fluid-pipe system. The numerical results show that the model is able to reproduce flow features including the attenuation and the phase shift of intense pressure waves which occurs in water hammer phenomena. [ABSTRACT FROM AUTHOR]

The general integral expressions for the elements of the ground impedance matrix do not have an analytical inverse transform in the time domain. Therefore, the ground transient resistance of a multiconductor line is commonly evaluated in the time domain by means of approximated expressions in order to avoid the numerical inverse fast Fourier transform burden. In this paper, we propose a new analytical approach for calculating the transient ground resistance in the time domain that stands on the very accurate Sunde logarithmic expression for the ground impedance matrix of an overhead multiconductor line. The proposed analytical approach is adopted for calculating lightning induced voltages in a multiconductor overhead line. The results show that the proposed analytical formula is in perfect agreement with the numerical inverse Fourier transform of the general Sunde expression and, therefore, is more accurate than the approximated expressions available in the literature. [ABSTRACT FROM AUTHOR]

Aim To evaluate the surface and microstructural alterations of new and used HyFlex EDM prototypes and to test their fatigue resistance. Methodology Fifteen HyFlex EDM prototypes were used for in vitro instrumentation of severely curved root canals. Surface and microstructural characteristics of new and used files were compared by ESEM analysis equipped with energy dispersive X-ray spectrophotometry ( EDS) and optical metallographic imaging. Usage-induced degradation was assessed. Thirty additional HyFlex EDM prototypes and 20 standard manufactured HyFlex CM files were subjected to cyclic fatigue tests. Time to fracture was recorded, and results were validated using the Kruskal-Wallis test (α-level 0.05). Fatigued files were analysed by ESEM for fractographic evaluation. Results Surface and microstructural characterization of EDM prototypes revealed the typical spark-machined surface of a NiTi EDM alloy. No fractures were registered during root canal instrumentation. No evident surface alterations and minor degradation were observed between new and used instruments. The metallographic analysis of new and used files disclosed a homogeneous structure, mostly composed of lenticular martensite grains, and some residual austenite. The cyclic fatigue test showed an increase of fatigue resistance up to 700% on the EDM compared to CM files. Conclusions Spark-machined peculiar surface is the main feature of HyFlex EDM. Low degradation was observed after multiple canal instrumentations. Prototypes exhibited surprising high values of cyclic fatigue resistance and a safe in vitro use in severely curved canals. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate fixation stability using two different fixation targets with the Nidek MP1 microperimeter. Twenty-nine healthy subjects with a mean age of 26.53 ± 7.35 years and visual acuity ≥0.0 logMAR were enrolled in this study. Fifty-eight eyes of 29 patients without ophthalmic and/or systemic disease underwent a fixation test with the MP1 microperimeter. Fixation stability related to a red cross (central) and/or a red circle (pericentral) target was quantified using either Fujii classification or by calculating the bivariate contour ellipse area (BCEA). For statistical analysis, BCEA values were converted into their logarithms (logBCEA) and all data obtained were analyzed using paired Student's t test. The inclination values of the axis of BCEA were analyzed with Chi squared test. The mean values of logBCEA and the mean values of the major and minor axis of the ellipses related to the cross and the circle fixation target were significantly different (68.2 %, p = 0.00; 95.4 %, p = 0.00; 99.6 %, p = 0.00, respectively) for each BCEA standard deviation. Fixation was significantly less stable for the pericentral fixation target in normal subjects, indicating an advantage for central fixation targets. These results are of particular interest when evaluation of changes in fixation is needed. [ABSTRACT FROM AUTHOR]

This paper deals with the theoretical derivation of the conservation equations for single phase flow in a porous medium. The derivation is obtained within the framework of the continuum mechanics and classical thermodynamics. The adopted procedure provides the conservation equations of mass, momentum, mechanical energy, total energy, internal energy, entropy, temperature, enthalpy, Gibbs free energy and Helmholtz free energy. The obtained results highlight the connection between the basic equations of fluid mechanics and of fluid flow in porous media, as well as the restrictions and the limitations of Darcy's law and Richards' equation. [ABSTRACT FROM AUTHOR]

Thyroid Associated Ophthalmopathy (TAO) is a complex pathology to treat and a considerable threat for Graves' Disease (GD) patients. Thus, there is great interest to find tools able to predict the onset and prognosis of TAO. Chronic inflamed tissues are characterized by tissue damage and recruitment of cells from the bloodstream, events that can lead to self-antigen exposure and induce autoimmune phenomena. In this study, we determined whether the occurrence of antibody anti-extracellular matrix (ECM) molecules [Collagen CI, CIII, CIV, CV, laminin (LM) and fibronectin, (FN)], anti-smooth muscle (ASM), anti-nuclear antigen (ANA), anti-ribonucleoprotein (RNP) and anti-thyroid-stimulating hormone (TSH) receptor (TRAbs) were associated with TAO in GD patients. We analyzed serum of 50 patients affected by GD, 24 of whom were affected by TAO, and 40 healthy donors (HD). The occurrence of TRAbs or ANA, anti-SM and anti-RNP antibodies did not allow to discriminate TAO+ from TAO- GD patients. Among the 24 TAO+ and 26 TAO- patients, 15/24 and 17/26 displayed TRAbs, respectively. None of the GD patients displayed anti-RNP antibodies, while 20/24 TAO+ and 17/26 TAO- patients were found to be positive for ANA and 3/24 TAO+ and 4/26 TAO- patients showed anti-SM antibodies. Conversely, when compared with HD control sera, GD sera showed antibodies to all individual ECM molecules. Remarkably, anti-CIII autoantibodies of the IgG isotype were significantly associated with GD TAO+ patients (p=0.045). Indeed, 6 out of 24 GD TAO+ patients scored positive for anti-CIII IgGs as compared to only 1 out of 26 TAO-. Our results suggest the potential involvement of anti-ECM antibodies in GD and a contribution of anti-CIII IgGs in TAO pathogenesis of GD patients. [ABSTRACT FROM AUTHOR]

Within the framework of one-dimensional unsteady compressible flow in deformable pipes, the present work proposes expressions able to represent the stress state of a 'fluid-pipe' continuous system. The coefficients needed to define the friction forces are calibrated against experimental results. The proposed expressions highlight the crucial role played by the fluid compressibility on the wave resistance. [ABSTRACT FROM AUTHOR]

Background: Inflammation triggers secondary neurodegeneration in multiple sclerosis (MS).Objectives: It is unclear whether classical anti-inflammatory cytokines have the potential to interfere with synaptic transmission and neuronal survival in MS.Methods: Correlation analyses between cerebrospinal fluid (CSF) contents of anti-inflammatory cytokines and molecular, imaging, clinical, and neurophysiological measures of neuronal alterations were performed.Results: Our data suggest that interleukin-13 (IL-13) plays a neuroprotective role in MS brains. We found, in fact, that the levels of IL-13 in the CSF of MS patients were correlated with the contents of amyloid-β1-42. Correlations were also found between IL-13 and imaging indexes of axonal and neuronal integrity, such as the retinal nerve fibre layer thickness and the macular volume evaluated by optical coherence tomography. Furthermore, the levels of IL-13 were related to better performance in the low-contrast acuity test and Multiple Sclerosis Functional Composite scoring. Finally, by means of transcranial magnetic stimulation, we have shown that GABAA-mediated cortical inhibition was more pronounced in patients with high IL-13 levels in the CSF, as expected for a neuroprotective, anti-excitotoxic effect.Conclusions: The present correlation study provides some evidence for the involvement of IL-13 in the modulation of neuronal integrity and synaptic function in patients with MS. [ABSTRACT FROM AUTHOR]

The article focuses on a study on non-hydrostatic pressure and the non-uniform velocity effects using different coefficients of the kinetic energy, momentum and piezometric head. It notes on the justification on the difference in energy and momentum principles in hydraulics but they believe that such explanation is not acceptable. It states that the authors' flow process has one-dimensional character.

The paper presents a procedure for fault location in distribution networks, based on the use of the integrated time-frequency wavelet decompositions of the voltage transients associated with the fault-originated travelling waves. The proposed analysis of time-frequency wavelet decompositions has been found to improve the identification accuracy of the frequencies associated to the characteristic patterns of a fault location with respect to a sole frequency-domain wavelet analysis. Several laboratory fault tests, carried out by means of a reduced-scale model of a distribution feeder, are used to illustrate the characteristics and assess the performances of the proposed improved procedure. The paper also illustrates the application of the proposed procedure to a transient, originated by a permanent phase-to-phase fault, measured in a real distribution network in which a post-test analysis has identified the faulted branch. [ABSTRACT FROM PUBLISHER]

Gaibani P, Caroli F, Nucci C, Sambri V. Major surface protein complex of Treponema denticola induces the production of tumor necrosis factor [alpha] , interleukin-1[beta], interleukin-6 and matrix metalloproteinase 9 by primary human peripheral blood monocytes. J Periodont Res 2010; 45: 361-366. © 2010 John Wiley & Sons A/S Background and Objective: Treponema denticola is a micro-organism that is involved in the pathogenesis of periodontitis. Major surface protein complex (MSPc), which is expressed on the envelope of this treponeme, plays a key role in the interaction between T. denticola and gingival cells. The peptidoglycan extracted from T. denticola induces the production of a large variety of inflammatory mediators by macrophage-like cells, suggesting that individual components of T. denticola cells induce the inflammatory response during periodontal disease. This study was designed to demonstrate that MSPc of T. denticola stimulates release of proinflammatory mediators in primary human monocytes. Material and Methods: Primary human monocytes were separated from the blood of healthy donors and incubated for up to 24 h with varying concentrations of MSPc. The production of tumor necrosis factor [alpha] (TNF-[alpha]), interleukin-1[beta] (IL-1[beta]), interleukin-6 (IL-6) and matrix metalloproteinase 9 (MMP-9) was measured at different time points with commercially available enzyme-linked immunosorbent assays. Results: T. denticola MSPc induced the synthesis of TNF-[alpha], IL-1[beta], IL-6 and MMP-9 in a dose- and time-dependent manner. Similar patterns of TNF-[alpha], IL-1[beta] and IL-6 release were observed when cells were stimulated with 100 and 1000 ng/mL of MSPc. The production of MMP-9 was significant only when cells were treated with 1000 ng/mL of MSPc. Conclusion: These results indicate that T. denticola MSPc, at concentrations ranging from 100 ng/mL to 1.0 [mu]g/mL, activates a proinflammatory response in primary human monocytes. [ABSTRACT FROM AUTHOR]

Gaibani P, Caroli F, Nucci C, Sambri V. Major surface protein complex of Treponema denticola induces the production of tumor necrosis factor α , interleukin-1β, interleukin-6 and matrix metalloproteinase 9 by primary human peripheral blood monocytes. J Periodont Res 2010; 45: 361–366. © 2010 John Wiley & Sons A/S Background and Objective: Treponema denticola is a micro-organism that is involved in the pathogenesis of periodontitis. Major surface protein complex (MSPc), which is expressed on the envelope of this treponeme, plays a key role in the interaction between T. denticola and gingival cells. The peptidoglycan extracted from T.  denticola induces the production of a large variety of inflammatory mediators by macrophage-like cells, suggesting that individual components of T.  denticola cells induce the inflammatory response during periodontal disease. This study was designed to demonstrate that MSPc of T. denticola stimulates release of proinflammatory mediators in primary human monocytes. Material and Methods: Primary human monocytes were separated from the blood of healthy donors and incubated for up to 24 h with varying concentrations of MSPc. The production of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and matrix metalloproteinase 9 (MMP-9) was measured at different time points with commercially available enzyme-linked immunosorbent assays. Results: T.  denticola MSPc induced the synthesis of TNF-α, IL-1β, IL-6 and MMP-9 in a dose- and time-dependent manner. Similar patterns of TNF-α, IL-1β and IL-6 release were observed when cells were stimulated with 100 and 1000 ng/mL of MSPc. The production of MMP-9 was significant only when cells were treated with 1000 ng/mL of MSPc. Conclusion: These results indicate that T.  denticola MSPc, at concentrations ranging from 100 ng/mL to 1.0 μg/mL, activates a proinflammatory response in primary human monocytes. [ABSTRACT FROM AUTHOR]

PurposeTo obtain age-specific data on changes in the prevalence and management of optically correctable visual impairments (OCVIs) in Ponza, Italy.MethodsOphthalmologic examinations were carried out to 1000 Ponzans aged 40–87 years in 1988 and to 836 persons in 2000. Visual acuity (VA) was evaluated under uncorrected (VAUC), presenting (VAPR), and best-corrected (VABC) conditions. We calculated the prevalence of total OCVIs (subjects with VAUC>0.5 logMAR and VABC0.5 logMAR in the better eye), uncorrected OCVIs (VAPR>0.5 logMAR), and corrected OCVIs (VAPR0.5 logMAR) as well as the OCVI correction rate ((corrected OCVI/total OCVI) × 100). Subjects with uncorrected OCVIs were compared to those with corrected OCVIs to evaluate possible associations with some risk factors.ResultsAmong 52- to 63-year olds there were increases in the prevalence of total OCVI (from 15.7 to 22.7%, P=0.051), corrected OCVI (from 10.9 to 19.9%, P=0.005), and OCVI correction rate (from 69.2 to 87.8%, P=0.045). Among 64- to 75-year olds decreases were observed in the prevalence of total OCVI (from 28.5 to 20.0%, P=0.029) and uncorrected OCVI (from 12.6 to 4.8%, P=0.003) while the OCVI correction rate increased from 55.9 to 76.1% (P=0.033). The overall prevalence of uncorrected OCVIs dropped from 7.5 to 4.1%. In 2000, uncorrected OCVI was associated with limited education, very advanced age, retirement, and refractive error associated with eye diseases.ConclusionsRefractive error management has improved in Ponza since 1988, and these changes may be, in part, due to higher education levels, increased frequency of cataract surgery, and slower progression of cataract-related disability.Eye (2009) 23, 522–529; doi:10.1038/eye.2008.104; published online 18 April 2008 [ABSTRACT FROM AUTHOR]

Loss of retinal ganglion cells occurs in a variety of pathological conditions, including central retinal artery occlusion, diabetes and glaucoma. Using an experimental model of retinal ischemia induced by transiently raise the intraocular pressure (IOP), In this study, we report the original observation that ischemic retinal ganglion cells death is associated with the transient deactivation of the pro-survival kinase Akt and activation of GSK-3β followed, during reperfusion, by a longer lasting, PI3K-dependent, activation of Akt and phosphorylation of GSK-3β. Under these experimental conditions, retinal ischemia induced the expression of Bad, a pro-apoptotic protein, member of the Bcl-2 family. The detrimental effects yielded by the ischemic stimulus were minimized by intravitreal administration of the NMDA receptor antagonist, MK801, that reduced the expression of Bad and significantly increased Akt phosphorylation. In conclusion, our present results contribute to unravel the mechanisms underlying retinal damage by high IOP-induced transient ischemia in rat. In addition, these data implicate the pro-survival PI3K/Akt pathway and the observed reduced expression of Bad in the neuroprotection afforded by MK801. [ABSTRACT FROM AUTHOR]

AimThe scientific literature contains recent data on the prevalence of blindness and low vision for a few European countries, but most of these studies have been focused exclusively on the elderly sector of the populations. The purpose of the present study was to provide age-specific estimates of the prevalence and causes of visual loss in an Italian population aged 40 years and over.MethodsIn total, 847 of the 1200 citizens >40 years of age (70.6%) in the island community of Ponza underwent complete standardized ophthalmological examinations. Visual acuity (VA) was measured using a standard logarithmic chart. World health organization (WHO) definitions of blindness and low vision were adopted (respectively, VA>1.3 logMAR or a visual field <10° around central fixation, and VA >0.5 to 1.3 logMAR or a visual field <20° around central fixation). Prevalence rates based on presenting VAs were also calculated.ResultsThe overall best-corrected prevalence rates were 0.6% (presenting, 0.8%) for better eye blindness, 2.1% (presenting, 6.7%) for better eye low vision, 1.8% (presenting, 2.6%) for monocular blindness, 5.0% (presenting, 11.2%) for monocular low vision. Cataract, glaucoma, degenerative myopia, and AMD were the main causes of better eye visual loss.ConclusionAge-specific prevalence rates in Ponza are fairly consistent with those for other European countries with similar socio-economic conditions and public healthcare systems. A substantial percentage of visual losses remains uncorrected despite the availability of potentially curative therapy. Greater emphasis needs to be placed on educating the public regarding the importance of good vision.Eye (2006) 20, 661–667. doi:10.1038/sj.eye.6701934; published online 27 May 2005 [ABSTRACT FROM AUTHOR]

Background: Resource utilisation and direct costs associated with glaucoma progression in Europe are unknown. As population progressively ages, the economic impact of the disease will increase. Methods: From a total of 1655 consecutive cases, the records of 194 patients were selected and stratified by disease severity. Record selection was based on diagnoses of primary open angle glaucoma, glaucoma suspect, ocular hypertension, or normal tension glaucoma; 5 years minimum follow up were required. Glaucoma severity was assessed using a six stage glaucoma staging system based on static threshold visual field parameters. Resource utilisation data were abstracted from the charts and unit costs were applied to estimate direct costs to the payer. Resource utilisation and estimated direct cost of treatment, per person year, were calculated. Results: A statistically significant increasing linear trend (p = 0.018) in direct cost as disease severity worsened was demonstrated. The direct cost of treatment increased by an estimated €86 for each incremental step ranging from €455 per person year for stage 0 to €969 per person year for stage 4 disease. Medication costs ranged from 42% to 56% of total direct cost for all stages of disease. Conclusions: These results demonstrate for the first time in Europe that resource utilisation and direct medical costs of glaucoma management increase with worsening disease severity. Based on these findings, managing glaucoma and effectively delaying disease progression would be expected to significantly reduce the economic burden of this disease. These data are relevant to general practitioners and healthcare administrators who have a direct influence on the distribution of resources. [ABSTRACT FROM AUTHOR]

This paper presents experimental results obtained at the International Center for Lightning Research and Testing (ICLRT) at Camp Blanding, Florida during the summers of 2002 and 2003. Currents induced by triggered and natural lightning events were measured at the terminations of a buried power cable, in the cable shield, and in the inner cable conductor. Measurements of the horizontal component of the magnetic field above the ground surface for both natural and triggered lightning are also presented. For distant natural lightning events, locations of ground strike points were determined using the U.S. National Lightning Detection Network (NLDN). Based on the theoretical developments presented in Part I of this paper [14], the field-to-buried cable coupling equations are solved in both the time domain and in the frequency domain. The obtained experimental results are then used to validate the numerical simulations provided by the relevant developed codes. [ABSTRACT FROM AUTHOR]

In this paper, we present a review of theoretical methods to compute lightning induced currents and voltages on buried cables. The evaluation of such induced disturbances requires the calculation of the electric field produced by lightning along the cable path. We show that the Cooray's simplified formula is capable of predicting accurately the horizontal electric field penetrating the ground, at distances as close as 100 m. Regarding the parameters of the buried cable, a comparison of several approximations of the ground impedance is presented. We show that the Pollaczek expression corresponds to the Sunde general expression, when the displacement current is neglected. The analysis shows also that all the proposed approximations provide very similar results for the considered range of frequencies (up to 30 MHz). Most of the approximate formulas neglect the contribution of the displacement current and, therefore, predict values for the ground impedance which tend to infinity at higher frequencies. This corresponds in the time domain to a singularity of the ground transient resistance at t = 0. By analogy to the Sunde approximation for the ground impedance of overhead lines, we propose a logarithmic approximation for the ground impedance of a buried cable. In addition, unlike most of the considered approximations, the proposed formula has an asymptotic behavior at high frequencies; therefore, the corresponding transient ground resistance in the time domain has no singularity at t = 0. It is also demonstrated that within the frequency range of interest, the wire impedance can be neglected, due to its small contribution to the overall longitudinal impedance of the line. The ground admittance, however, can play an important role at high frequencies (1 MHz or so) especially in the case of poor ground conductivity. The ground admittance needs to be taken into account in the calculation of lightning induced currents and voltages on buried cables. This is in contrast with the case of overhead lines in which its contribution is generally negligible, even in the MHz range. We also investigate the time-domain representation of field-to- transmission line coupling equations. The coupling model includes the effect of ground admittance which appears in terms of an additional convolution integral. An analytical expression for the ground transient resistance in the time domain is also proposed which is shown to be sufficiently accurate and nonsingular. Finally, we present a time domain solution of field-to-buried cable coupling equations using the point-centered finite difference time domain (FDTD) method, and a frequency domain solution using Green's functions. In our companion paper (Part II), we compare both solutions to experimental waveforms obtained using triggered lightning. [ABSTRACT FROM AUTHOR]

AIM:To study the incidence of visual loss over a 12-year period in the survivors of an original cohort aged 40 years or older at baseline. METHODS:Visual acuity (VA) was measured by means of a standardized logMAR chart. World Health Organization definition of blindness and low vision was adopted (respectively, best-corrected VA>1.3?logMAR or a visual field<10°around central fixation, and best-corrected VA>0.5-1.3?logMAR or a visual field<20°around central fixation). Moreover, binocular visual loss incidence (VA>0.5?logMAR) was calculated in a‘healthy’group who had uncorrected VA of 0.0?logMAR or better in both eyes at baseline and absence of eye diseases. RESULTS:Of the 584 eligible survivors, 411 (70.7%) had a 12-year follow-up visit. The overall incidence figures were as follows: best-corrected binocular blindness (0.7%), binocular low vision (3.9%), monocular blindness (2.7%), and monocular low vision (5.0%), respectively. The results for presenting VAs were 1.2, 9.5, 4.2, and 15.3%. Figures for uncorrected, best-corrected, and presenting binocular visual loss incidence in the‘healthy’group were respectively 12.7, 0.9, and 3.7%. CONCLUSION:The discrepancy between the ideal and real situations that emerges from this study has important implications for health-care planning. Over a period of 12 years, a substantial percentage of‘healthy’subjects will have to seek medical care. Incident visual loss was caused mainly by untreated cataract, glaucoma, myopia, and age-related macular degeneration.Eye (2005) 19, 175-182. doi:10.1038/sj.eye.6701444 Published online 25 June 2004 [ABSTRACT FROM AUTHOR]

Foschi F, Nucci C, Montebugnoli L, Marchionni S, Breschi L, Malagnino VA, Prati C.SEM evaluation of canal wall dentine following use of Mtwoand ProTaper NiTi rotary instruments.International Endodontic Journal,37, 832–839, 2004.To compare using scanning electron microscopy (SEM) root canal walls following instrumentationin vitrowith two different rotary NiTi instruments. The hypothesis was that no difference should be observable between the experimental groups in terms of debris on canal walls and surface morphology.Twenty-four single-rooted human teeth were selected. Two types of NiTi instruments were used, Mtwo(Sweden&Martina, Padova, Italy) and ProTaper (Dentsply Maillefer, Ballaigues, Switzerland). Irrigation for both groups was performed after each instrument change with 5% NaOCl, 3% H2O2 and 17% EDTA solutions. Three different areas (coronal, middle and apical thirds) of the root canal were evaluated using SEM. The canal wall of each sample was assessed and compared using a predefined scale of four parameters, namely, smear layer, pulpal debris, inorganic dentine debris, surface profile. Data were analysed statistically using the Kruskal–Wallis test (anova).A statistically significant difference (P <0.01) was found between the apical third and the middle and coronal thirds for both groups. No difference was observable between instrumentation groups. In the apical third canal walls were often contaminated by inorganic debris and by smear layer. In the apical third, the surface profile was affected by uninstrumented regions, comprising dentine depressions and grooves in which predentine was still visible.Both instruments produced a clean and debris-free dentine surfaces in the coronal and middle thirds, but were unable to produce a dentine surfaces free from smear layer and debris in the apical third. The presence of deep grooves and depression on dentine walls in the apical third may well explain the presence of less-instrumented areas. [ABSTRACT FROM AUTHOR]

This paper presents a new approach to model a transmission tower for lightning performance studies. It consists of representing each part of the tower by equivalent vertical and/or horizontal transmission lines as required. While horizontal line parameters are obtained from standard line formulas, specific expressions are derived for the parameters of vertical lines. Moreover, mutual coupling between any two parallel vertical transmission lines is taken into account. Transient waveforms obtained using the proposed method are compared with experimental data obtained using a reduced-scale model and field experiments. The agreement between simulated results and experimental measurements is satisfactory. [ABSTRACT FROM AUTHOR]

Background: There are many different strategies for the treatment of the main bile duct lithiasis. When lithiasis of the biliary tract is suspected at a preoperative stage, we can treat patients with sequential treatment: endoscopic netrograde cholangiopancreatography followed by laparoscopic cholecystectomy. If common bile duct-lithiasis is recognized at an intraoperative stage, many options for treatment exist, one of which is intraoperative retrograde endoscopic sphincterotomy (ES) (laparoendorendezvous).Methods: We report our experience using the aforementioned technique with 58 patients affected by cholelithiasis and complex Common bile duct disease who underwent laparoscopic cholecystectomy and intraoperative ES consecutively from March 1996 to May 2000. Of the 58 patients, 43 were affected by cholecystocholedocolithiasis: 12 by previously described lithiasis plus stenosant papillitis, 2 also by a pancreas head cancer, and 1 by cancer of the papilla.Results: The combined technique was performed in 86% of the cases. Six patients required conversion to open surgery. In two other patients, laparoscopic choledocotomy was performed with positioning of a Kehr-tube for an ampulla-impacted lithiasis.Conclusions: Intraoperative ES offers a valid approach to the treatment of cholecystocholedocolithiasis in one session. Furthermore, it represents a valid alternative to transcholedocical laparoscopic treatment of cholelithiasis and complex common bite duct pathology. [ABSTRACT FROM AUTHOR]