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Introduction Medical photography is a noninvasive technique used for diagnostic, monitoring, and educational purposes. It is important to understand the patient's attitude to all or part of their body being photographed. The objective of this study was to analyze the attitudes of patients towards medical photography at a district hospital in Tarragona, Spain. Methodology This exploratory study used a questionnaire to evaluate attitudes to medical photography among outpatients at Pius Hospital de Valls. The questionnaire explored the patients’ beliefs about the usefulness of medical photography, the circumstances in which they would agree to be photographed and by whom, as well as their prior experience of medical photography. They were also asked whether they would authorize the use of photography and, if not, to explain their motives. Results The questionnaire was completed by 134 patients. The results showed that patients had a clearly positive attitude to being photographed for medical purposes (94.8%), treatment follow-up (88.1%), and consultation of their case with other physicians (86.6%). Acceptance was 88.8% if the lesion was malignant and 85.1% if it was extensive. For facial lesions, only 78.4% were willing to be photographed and in the case of genitals the percentage fell to 70.2%. Most patients (95.5%) would agree to being photographed by their doctor. The rate of acceptance was 66.4% in the case of a nurse, 64.9% for another doctor, and 21.6% for a professional photographer. Conclusions Our study revealed that patients have a positive attitude to being photographed for medical purposes, particularly when they have a malignant lesion, when the photograph is taken by their specialist, and when they cannot be identified.

Resumen Introduccion La fotografia medica es una tecnica de imagen no invasiva que se utiliza con fines diagnosticos, de monitoreo y educativos. Es importante conocer la actitud del paciente hacia ser fotografiado, en su totalidad o en parte de su cuerpo. El objetivo de este estudio es analizar la actitud de los pacientes del Pius Hospital de Valls hacia la fotografia medica. Metodologia Este estudio exploratorio evaluo, a partir de un cuestionario, la actitud de los pacientes que asistieron a consultas externas del Hospital Pius de Valls (Espana) respecto a ser fotografiados. Las preguntas estaban relacionadas con creencias en torno a la utilidad de la fotografia medica, circunstancias bajo las cuales se autorizaria ser fotografiado y a manos de quien, experiencia con la fotografia medica, intencion de autorizar la fotografia y motivos para no autorizarla. Resultados El cuestionario fue respondido por 134 pacientes. Los resultados mostraron una actitud claramente positiva hacia ser fotografiado con fines medicos (94,8%), por seguimiento de tratamiento (88,1%) y consulta del caso con otros medicos (86,6%). El 88,8% aceptaria ser fotografiado si la lesion es maligna y el 85,1% si es extensa. Para lesiones en el rostro, solamente el 78,4% lo permitiria; en los genitales el porcentaje es aun menor (70,2%). El 95,5% estaria dispuesto a dejarse fotografiar si es el mismo medico quien la hace, si es el enfermero (66,4%), otro medico (64,9%) o un fotografo profesional (21,6%). Conclusiones Nuestro estudio muestra una actitud positiva hacia ser fotografiado con fines medicos, siempre que el fotografo sea el medico tratante, en lesiones malignas y en areas no identificables.

Among the renewable energy technologies, offshore wind energy is expected to provide a significant contribution for the achievement of the European Renewable Energy (RE) targets for the next future. In this framework, the increase of generated power combined with the alleviation of vibratory loads achieved by application of suitable advanced control systems can lead to a beneficial LCOE (Levelized Cost Of Energy) reduction. This paper defines a control strategy for increasing floating offshore wind turbine lifetime through the reduction of vibratory blade and hub loads. To this purpose a Proportional-Integral (PI) controller based on measured blade-root bending moment feedback provides the blade cyclic pitch to be actuated. The proportional and integral gain matrices are determined by an optimization procedure whose objective is the alleviation of the vibratory loads due to a wind distributed linearly on the rotor disc. This control synthesis process relies on a linear, state-space, reduced-order model of the floating offshore wind turbine derived from aero-hydroelastic simulations provided by the open-source tool OpenFAST. In addition to the validation of the proposed controller, the numerical investigation based on OpenFAST predictions examines also the corresponding control effort, influence on platform dynamics and expected blade lifetime extension. The outcomes show that, as a by-product of the alleviation of the vibratory out-of-plane bending moment at the blade root, significant reductions of both cumulative blade lifetime damage and sway and roll platform motion are achieved, as well. The maximum required control power is less than 1% of the generated power.

This work presents the correlation between experimental measurements and numerical simulations concerning the aerodynamics of a hovering rotor operating in ground effect above parallel and inclined surfaces. The capability of a potential-flow, free-wake aerodynamic solver based on a boundary-element-method formulation to simulate in-ground-effect problems is examined in detail. In particular, two approaches for including ground effect are outlined and compared, namely the bounded domain method and the mirror image method. Analyses of rotor aerodynamic performance and flow-field visualization reveal that the experimental data and the numerical predictions given by the solver based on the mirror-image method are in good agreement, thus proving the suitability of this developed computational tool to simulate rotor aerodynamics in the presence of close ground. Concerning the bounded domain method, it has been proven that it is suitable for the evaluation of rotor thrust and wake shape close to the rotor, but does not provide accurate simulation of the flow-field in proximity to the ground and corresponding inflow over the rotor disk.

This paper presents an investigation of the aerodynamic and aeroacoustic interaction of propellers for distributed electric propulsion applications. The rationale underlying the research is related to the key role that aeroacoustics plays in the establishment of the future commercial aviation scenario. The sustainable development of airborne transportation system is currently constrained by community noise, which limits the operations of existing airports and prevents the building of new ones. In addition, the substantial saturation of the existing noise abatement technologies inhibits the further development of the existing fleet, and imposes the adoption of disruptive configurations in terms of airframe layout and propulsion technology. Simulation-based data may help in clarifying many aspects related to the acoustic impact of such innovative concepts. Blended-wing-body equipped with distributed electric propulsion is one of the most promising, due to the beneficial effect of the substantial shielding induced by its geometry. Nevertheless, the novelty of the layout requires a thorough investigation of specific aspect for which no previous experience is available. Herein, the interaction between propellers is analysed for a fixed propeller geometry, as a function of their mutual distance and compared to the acoustic pattern of the isolated one. The aerodynamic results have been obtained using a boundary integral formulation for unsteady, incompressible, potential flows which accounts for the interaction between free wakes and propellers. For the aeroacoustic analyses, the Farassat 1A boundary integral formulation for the solution of the Ffowcs Williams and Hawkings equation has been used. These results provide an insight into the minimum distance between propellers to avoid aerodynamic/aeroacoustic interaction effects, which is an important starting point for the development of distributed propulsion systems.

This paper deals with the aeroacoustic analysis of helicopter rotors operating in ground effect. Assuming the ground to be a purely reflective flat surface, the scope is twofold: comparison of different techniques to model its presence and assessment of its effects on the emitted noise field. To this purpose, the mirror image method is applied to evaluate the influence of the ground on the aerodynamic sound sources distributed over the rotor blades (indirect acoustic effect), whereas a noise scattering formulation is used to determine its effects as a sound reflecting surface impinged by the pressure field radiated by the rotor (direct acoustic effect). The numerical investigations examine the impact of the rotor height above the ground both on near and far field noise, and provide highlights on potentialities and drawbacks of the different modeling approaches considered.

Chronic allergic inflammatory diseases are a major cause of morbidity, with allergic asthma alone affecting over 300 million people worldwide. Epidemiological studies demonstrate that environmental stimuli are associated with either the promotion or prevention of disease. Major reductions in asthma prevalence are documented in European and US farming communities. Protection is associated with exposure of mothers during pregnancy to microbial breakdown products present in farm dusts and unprocessed foods and enhancement of innate immune competence in the children. We sought to develop a scientific rationale for progressing these findings toward clinical application for primary disease prevention. Treatment of pregnant mice with a defined, clinically approved immune modulator was shown to markedly reduce susceptibility of their offspring to development of the hallmark clinical features of allergic airway inflammatory disease. Mechanistically, offspring displayed enhanced dendritic cell–dependent airway mucosal immune surveillance function, which resulted in more efficient generation of mucosal-homing regulatory T cells in response to local inflammatory challenge. We provide evidence that the principal target for maternal treatment effects was the fetal dendritic cell progenitor compartment, equipping the offspring for accelerated functional maturation of the airway mucosal dendritic cell network following birth. These data provide proof of concept supporting the rationale for developing transplacental immune reprogramming approaches for primary disease prevention.

Studies in European and US farming populations have documented major reductions in asthma prevalence in offspring of mothers exposed to microbial breakdown products present in farm dusts and unprocessed foods. This was associated with enhancement of innate immune competence in the offspring. We sought to (i) identify a safe therapeutic that would reproduce these immunomodulatory effects in a murine model, (ii) elucidate underlying mechanism(s)-of-action, and (iii) develop a scientific rationale for progressing this approach to human trials. We demonstrate in mice that maternal treatment during pregnancy with the microbial-derived immunomodulator OM85, which has been used clinically in adults and children in Europe for >30 years for bolstering resistance to infection-associated airways inflammation, markedly reduces the susceptibility of the offspring of treated mothers to development of experimental atopic asthma. We identify bone marrow precursors of the dendritic cell populations responsible for airway mucosal immune surveillance as the primary targets for the asthma-protective effects of maternal OM85 treatment in the offspring.

The inflammasome–IL-1 axis and type I interferons (IFNs) have been shown to exert protective effects upon respiratory tract infections. Conversely, IL-1 has also been implicated in inflammatory airway pathologies such as asthma and chronic obstructive pulmonary disease (COPD). OM-85 is a bacterial extract with proved efficacy against COPD and recurrent respiratory tract infections, a cause of co-morbidity in asthmatic patients. We therefore asked whether OM-85 affects the above-mentioned innate immune pathways. Here we show that OM-85 induced interferon-β through the Toll-like receptor adaptors Trif and MyD88 in bone marrow-derived dendritic cells. Moreover, it exerted a dual role on IL-1 production; on the one hand, it upregulated proIL-1β and proIL-1α levels in a MyD88-dependent manner without activating the inflammasome. On the other hand, it repressed IL-1β secretion induced by alum, a well-known NLRP3 activator. In vivo, OM-85 diminished the recruitment of inflammatory cells in response to peritoneal alum challenge. Our findings therefore suggest that OM-85 favors a protective primed state, while dampening inflammasome activation in specific conditions. Taken together, these data bring new insights into the mechanisms of OM-85 action on innate immune pathways and suggest potential explanations for its efficacy in the treatment of virus-induced airway diseases.

This article proposes a set of equations that allow the calculation of the hydrophilic-lipophilic balance (HLB) value of polyoxyethylene esters from quality control data of the raw materials (fatty acids and polyethylene glycol) and the finished product (surfactant). The quality control data required include the acid value of the fatty acid, the hydroxyl value of the polyethylene glycol, and the hydroxyl value of the surfactant. Moreover, these calculations allow the determination of the mean relative molecular masses of the fatty acids, polyethylene glycol, monoesters, and diesters, and to calculate the proportion of polyoxyethylene monoester and polyoxyethylene diester. Models such as this would be of great utility for the rational design of emulsified products. Fil: Pasquali, Ricardo Conrado. Universidad de Buenos Aires. Facultad de Farmacia y Bioquimica. Departamento de Tecnologia Farmaceutica; Argentina; Universidad Tecnológica Nacional. Facultad Regional Avellaneda; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina; Fil: Helguera, Gustavo Fernando. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Tecnología Farmacéutica; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay; Argentina

Introduction Iterative reconstruction algorithms have been introduced in clinical practice to obtain dose reduction without compromising the diagnostic performance. Purpose To investigate the commercial Model Based IMR algorithm by means of patient dose and image quality, with standard Fourier and alternative metrics. Materials and methods A Catphan phantom, a commercial density phantom and a cylindrical water filled phantom were scanned both varying CTDIvol and reconstruction thickness. Images were then reconstructed with Filtered Back Projection and both statistical (iDose) and Model Based (IMR) Iterative reconstruction algorithms. Spatial resolution was evaluated with Modulation Transfer Function and Target Transfer Function. Noise reduction was investigated with Standard Deviation. Furthermore, its behaviour was analysed with 3D and 2D Noise Power Spectrum. Blur and Low Contrast Detectability were investigated. Patient dose indexes were collected and analysed. Results All results, related to image quality, have been compared to FBP standard reconstructions. Model Based IMR significantly improves Modulation Transfer Function with an increase between 12% and 64%. Target Transfer Function curves confirm this trend for high density objects, while Blur presents a sharpness reduction for low density details. Model Based IMR underlines a noise reduction between 44% and 66% and a variation in noise power spectrum behaviour. Low Contrast Detectability curves underline an averaged improvement of 35–45%; these results are compatible with an achievable reduction of 50% of CTDIvol. A dose reduction between 25% and 35% is confirmed by median values of CTDIvol. Conclusion IMR produces an improvement in image quality and dose reduction.

Infection-associated inflammatory stress during pregnancy is the most common cause of fetal growth restriction and/or miscarriage. Treatment strategies for protection of at-risk mothers are limited to a narrow range of vaccines, which do not cover the bulk of the common pathogens most frequently encountered. Employing mouse models, we demonstrate that oral treatment during pregnancy with a microbial-derived immunomodulator (OM85TM), currently used clinically for attenuation of infection-associated airway inflammatory symptoms in infants-adults, markedly reduces risk for fetal loss/growth restriction resulting from maternal challenge with bacterial LPS or influenza. Focusing on LPS exposure, we demonstrate that the key molecular indices of maternal inflammatory stress, notably high levels of RANTES, MIP-1a, CCL2, IL-8 and G-CSF in gestational tissues/serum, are abrogated by OM85 pretreatment. Systems-level analyses conducted in parallel employing RNASeq revealed that OM85 pretreatment selectively tunes LPS-induced activation in maternal gestational tissues for attenuated expression of TNF-, IL1-, and IFNg-driven that drive production of these pro-inflammatory cytokines, without constraining Type1-IFN-associated networks central to first-line anti-microbial defense. This study suggests that broad-spectrum protection-of-pregnancy against infection-associated inflammatory stress, without compromising capacity for efficient pathogen eradication, represents an achievable therapeutic goal.DisclosureThis study was funded principally by Nation Health and Medical Research Council (NHMRC) of Australia with supplementary support provided by OM Pharma (Geneva, Switzerland).CP is an employee of OM Pharma (Vifor Pharma). The other authors declare that they have no conflict of interest.

Infection-associated inflammatory stress during pregnancy is the most common cause of fetal growth restriction and/or miscarriage. Treatment strategies for protection of at-risk mothers are limited to a narrow range of vaccines, which do not cover the bulk of the common pathogens most frequently encountered. Using mouse models, we demonstrate that oral treatment during pregnancy with a microbial-derived immunomodulator (OM85), currently used clinically for attenuation of infection-associated airway inflammatory symptoms in infants-adults, markedly reduces risk for fetal loss/growth restriction resulting from maternal challenge with bacterial lipopolysaccharide or influenza. Focusing on LPS exposure, we demonstrate that the key molecular indices of maternal inflammatory stress, notably high levels of RANTES, MIP-1α, CCL2, KC, and G-CSF (granulocyte colony-stimulating factor) in gestational tissues/serum, are abrogated by OM85 pretreatment. Systems-level analyses conducted in parallel using RNASeq revealed that OM85 pretreatment selectively tunes LPS-induced activation in maternal gestational tissues for attenuated expression of TNF, IL1, and IFNG-driven proinflammatory networks, without constraining Type1-IFN-associated networks central to first-line antimicrobial defense. This study suggests that broad-spectrum protection-of-pregnancy against infection-associated inflammatory stress, without compromising capacity for efficient pathogen eradication, represents an achievable therapeutic goal.

La piel es un órgano apropiado para administrar principios activos con el fin de obtener efectos locales o sistémicos. Las formulaciones de uso tópico más comunes son: lociones, emulsiones, suspensiones, cremas, pomadas; las cuales deben reunir determinadas condiciones para ser aplicadas sobre la piel. El objetivo del presente trabajo es seleccionar una emulsión preparada con la técnica de formación de cristales líquidos compuesta de ácido esteárico, vaselina líquida, trietanolamina, propilparabeno, metilparabeno y agua, a la que se le incorpora un ingrediente farmacéutico activo liposoluble: econazol. El econazol, principio activo cuya vía de administración es la tópica y su acción es local, es una sustancia soluble en aceites, que se aloja en la fracción liposoluble de los cristales líquidos y en la fase interna de la emulsión sin que se modifique el perfil reológico ni la estabilidad de los sistemas. Se estudió además del HLB y de sus comportamientos reológicos, la presencia de cristales líquidos con luz polarizada, la existencia de gotas secundarias con luz común y la estabilidad de los sistemas por centrifugación y estrés térmico a temperaturas de 40 ºC. Los valores obtenidos en los estudios realizados, demostraron que la emulsión lograda presenta un perfil reológico y las condiciones de estabilidad adecuadas para ser utilizada como crema medicinal. The skin is the appropiate organ to administrate active principles in orden to obtain local or systemic effects. Formulations for topical use most common are: lotions, emulsions, suspensions, creams, ointments, which must gather certain conditions to be applied to the skin. In this work, the objective is to select an emulsion prepared by a technique of liquid crystals formation composed by stearic acid, mineral oil, triethanolamine, propylparaben, methylparaben and water. To this formula we incorporated a pharmaceutical active liposoluble ingredient: econazole. Econazole, a principle active with topical administration and local action, is a substance soluble in oils, which stays in the liposoluble fraction of the liquid crystals and in their internal phase of the emulsion without modifying their rheological profile not even the stability of systems. Besides the HLB of the systems and their rheological behaviour we also study the presence of liquid crystals with polarized light, the existence of secondary drops with common light and systems stability by centrifugation, thermal stress and temperatures of 40 °C. The values obtained from the studies made, demonstrated that the emulsion achieved present a rheological profile and stability conditions suitable for medicinal use cream.

This study proposes a method to estimate low contrast detectability LCD applying a statistical method, based on the analysis of a uniform region. A dedicated test object was designed, made up of an acetate sheet equipped with a central uniform insert and an aluminium step wedge, allowing linear conversion from pixel values to millimeters of aluminium. A Matlab program for automated image analysis was developed. Phantom images were acquired on two different digital mammography systems. Reproducibility and sensitivity to exposure variations of the proposed method were investigated for different dose levels. Further the impact of scattering and attenuation on LCD was studied adding PMMA layers of variable thickness 2 to 7i¾?cm upon the acetate sheet during exposure in automatic exposure control modality. The statistical method turned out to be a reliable and rapid method for LCD evaluation. Applications include routine assessment of equipment performance for digital mammography systems.

Purpose: The aim of this study was to assess the performance measurements of the new PET/CT system Discovery-600 (D-600, GEMS, Milwaukee, WI). Methods: Performance measures were obtained with the National Electrical Manufacturers Association (NEMA) NU 2-2007 procedures. Results: The transverse (axial) spatial resolution FWHMs were 4.9 (5.6) mm and 5.6 (6.4) mm at 1 and 10 cm off axis, respectively. The sensitivity (average at 0 and 10 cm) was 9.6 cps/kBq. The scatter fraction was 36.6% (low energy threshold: 425 keV). The NEC peak rate (k=1) was 75.2 kcps at 12.9 kBq/cc. The hot contrasts for 10, 13, 17, and 22 mm spheres were 41%, 51%, 62%, and 73% and the cold contrasts for 28 and 37 mm spheres were 68% and 72%. Conclusions: The Discovery-600 has good performance for the NEMA NU 2-2007 parameters, particularly in improved sensitivity compared to the scanners of the same Discovery family, D-ST and D-STE.

The influence of preparation methods on stability of lipogels was studied. The objectives of this study were to evaluate the ability of different low molecular solid ingredients used as excipients in pharmaceutical and cosmetical products to form lipogels with emollient liquids of different polarities as well as to evaluate the stability of the lipogels obtained and the spreading ability of stable lipogels. The lipogels were prepared by heating the mix of oil and gelator a 100°C with two different forms of cooling: slow cooling of the without stirring and quick cooling with stirring. The stability tests were one year of storage at room temperature, centrifugation and three months at 40°C. None of the lipogels prepared with slow cooling and without stirring were stable in all stability tests. Eight of the formulations with quick cooling and stirring were stables in all stability tests: six with 12-hydroxystearic acid, one with hydrogenated castor oil, and one with beeswax as gelators. The lipogels with 12-...

The goals of this articles are to find a correlation between the required HLB values and the solubility parameters of oils; find a more precise correlation between the required HLB values and the dielectric constant, than the one obtained by other authors; and to determine the required HLB values for o/w emulsions of solid fatty acids and alcohols from the values of the solubility parameters and dielectric constants, that could be more trustful than the ones obtained by the methodology proposed by Griffin. It was obtained lineal relation between required HLB and solubility parameter (r = 0.995). Also it was observed lineal relations between required HLB and dielectric constants or logarithm of the dielectric constant more precise than the one obtained by other authors.

The stratigraphy and theories on the origin of the "Pampean Sediments" are described. The terms "terrains pampéens" and "argile pampéennes" introduced by Alcide d'Orbigny have been used for more than 170 years. During this period, the theories and hypotheses on the origin and antiquity of the sediments and their faunas have changed. They have been considered marine or continental in origin, and to be Cretaceous to Pleistocene in age. This sequence and its paleontological content are currently form the basis of the chronological scheme for the last two million years in southern South America.

In this article, we obtained equations that permit us to calculate the hydrophilic-lipophilic balance (HLB) value of polyoxyethylene esters from quality control data of the raw materials (fatty acids and polyethylene glycol) and the finished product (surfactant). These data include the acid value of the fatty acid, the hydroxyl value of the polyethylene glycol, and the hydroxyl value of the surfactant. These calculations permit us, moreover, to know the mean molecular masses of fatty acids, of polyethylene glycol, of monoester and diester, and the proportion of polyoxyethylene monoester and polyoxyethylene diester.

In 1940, Flory deducted that the molecular distribution of ethylene oxide polymers, obtained by reaction of ethylene oxide with ethylene glycol, is represented by Poisson's distribution law. This mathematical equation was subsequently used by other authors for calculating the fractions molars of the products of the reaction of ethylene oxide with alcohols and phenols, without taking into account to be used as quantity of units of ethylene oxide to x instead of x − 1. In this article, it is theoretically demonstrated that if the equation obtained by Flory is modified in this way, it gets that the hydrophilic-lipophilic balance of non ionic polioxiethylenated surfactants can be calculated from the mean number of molecules of ethylene oxide that reacts with one molecule of alcohol or phenol.

Il presente studio ha come scopo di individuare la conducibilità idraulica di sedimenti recenti fini continentali su cui verrà impostata una cassa d’espansione. Sono state perciò eseguite prove di campagna (Boutwell, Lefranc e CPTU) e di laboratorio (permeabilità in cella edometrica su campioni indisturbati, granulometria per rifrazione laser e per vagliatura e determinazione dei limiti di consistenza). Dal confronto dei risultati ottenuti si è avuta conferma dell’importanza delle dimensioni del campione esaminato, a causa dell’influenza della macrostruttura, influenza che porta a variazioni di oltre un ordine di grandezza della conducibilità idraulica misurata in situ ed in laboratorio.

Introduction Contrast detail curve, or LCD, is an important aspect of image quality. LCD curves are usually determined with the Artinis CDMAM phantom. Purpose This study proposed a different method to obtain contrast detail curves based on a unique image of a homemade phantom. Materials and methods Phantom was made up of an acetate sheet equipped with a central uniform aluminium region ( 3 × 3 cm 2 , thickness 0.49 mm) and an aluminium step wedge (thickness: 0.2–1 mm) for linear conversion pixel values/millimetres of aluminium. LCD was estimated through a statistical method analysing a square ROI on the uniform aluminium region with a dedicated Matlab program. For each details dimension, it was divided into a matrix of subROIs: contrast thresholds were defined as 3.29 the standard deviation of subROIs mean values, corresponded to a statistical significance of 95%. Results were then converted in terms of mmAl. Reproducibility and variability with different combinations of kV, mAs and AGD were evaluated. Reliability of the method was evaluated comparing results with CDMAM curves. The effect of human perception was considered through a NPWE model and compared with the results of 2AFC experiment. Results Analysis confirmed the reproducibility of the method. The comparison with CDMAM analyses showed a good agreement for each equipment considered in this study, confirming the good reliability of the method. The Human perception was also introduced with good results. Conclusion The statistical approach proved to be less time-consuming and in accordance with the automatic readout of CDMAM images, allowing to be adopted in image quality assurance protocols.

Introduction In the last decades the population dose increase is mainly due to CT. Recently iterative reconstruction algorithms were introduced to obtain dose reduction without compromising the diagnostic performance. Purpose To investigate the effect of the model-based IMR algorithm in terms of image quality and patient dose. Materials and methods CATPHAN phantom was scanned varying CTDIvol values from 0.8 to 31.8ṁGy., FBP and IMR algorithms were used to reconstruct the images. Different IMR reconstruction curves were analysed: Routine, Soft and SharpPlus. The homogeneous insert was used to analyse noise in terms of standard deviation and NPS; Low Contrast Detectability with statistical method was investigated too. MTF was evaluated using a tungsten bead, TTF with a homemade phantom. Patient dose indexes have been collected and analysed. Results The averaged noise reduction for IMR routine and soft images is 45% and 66% respectively; IMR noise reduction works better for highly noisy images. LCD curve are better with IMR especially for small inserts and low doses. An averaged improvement of 35%–45% of contrast detectability with different curves has observed for 5 mm detail; these results are compatible with a reduction of 50% of CTDIvol on patient scans. IMR significantly improved MTF: MTF 50 increases by 12%, 24%, 64% with Soft, Routine and SharpPlus algorithm respectively; TTF curves confirm this trend. Dose reduction of 25% in cerebral exams and 50% in thorax-abdominal scans is confirmed by median values of CTDIvol from patient data. Conclusion IMR reduces noise, improves low contrast detectability and reduces dose.

The methods and results obtained by Griffin et al. in the determination of the hydrophilic-lipophilic balance (HLB) values of non-ionic surfactants and of required HLB values of oil mixtures are reviewed in the present work. HLB values published by Griffin were compared with those obtained by calculations from theoretic chemical formulas. Griffin HLB values of polyoxyethylene alkyl ethers, polyoxyethylene monoesters and propylene glycol monoesters coincide with those obtained from such theoretical chemical formulations. These results demonstrate that, for these surfactants, Griffin did not experimentally obtain their HLB values, but instead calculated them from theoretic formulae. For the calculation of the HLB values of glycerol monostearate, sorbitan fatty acid esters and polyoxyethylene sorbitan fatty acid esters, Griffin's assumptions were possibly based upon the mean saponification values of the ester and the acid of the fatty acid. It is concluded that the HLB values of non-ionic surfactants were not rigorously defined. Moreover, Griffin could not demonstrate the validity of the assumption that individual required HLB values can be added up to obtain the overall required HLB value of an oil mixture. The HLB and required HLB values published by Griffin should only be taken as approximate guidelines.

From November 1994 to November 2004, seventy-seven patients with neuroendocrine gastro-entero-pancreatic tumor (71% pancreatic) were investigated with 18-fluorine-deoxi-glucose positron emission tomography (FDG-PET). PET results were compared with CT-scan, MRI and octreoscan scintigraphy and clinico-pathologic features of patients and survival. Overall PET sensitivity was 57%; 78% of malignant tumors, 67% of borderline and 17% of benign tumors were detected by FDG-PET. No duodenal tumor was detected by PET scan. Only 16% of primary less than 2 cm in size was localized. In 16% of cases PET scan provided new information able to change therapeutic management. In PET positive patients the addictive information obtained by PET scan when compared with octreoscan, MRI and CT scan were respectively 50% more, 26% more and 30% more. In malignant neuroendocrine tumors PET positivity was related to short survival. No patient with malignant tumor died for disease progression in the follow-up when PET was negative, while 13/35 PET positive patients died (p0.003). FDG-PET proved to be a second line technique in neuroendocrine digestive tumors. PET results improve clinical staging of disease and is related to survival in malignant cases; in 16% of cases may change the therapeutic option.

Electronic transport properties have been measured in thin pseudomorphic SiGe alloys and heterostructures, grown by surfactant mediated epitaxy (SME), in order to investigate the unintentional doping effects caused by Sb, used as surfactant. In alloy films, we measured at 300 K, a Hall mobility (μ H = 20 cm 2 V -1 s -1 ) at least one order of magnitude lower than the undoped material (μ H = 100 cm 2 V -1 s -1 ), grown in similar conditions, but without surfactant. At low temperatures (40 K < T < 75 K) we obtained μ H values of about 3.6 x 10 4 cm 2 V -1 s -1 for SME grown material and up to 5.5 x 10 4 cm 2 V -1 s -1 , for undoped ones. Above 75 K, all the alloy samples showed a μ H decrease with the temperature steeply than the T - 1.5 dependence. Moreover, in undoped materials we observed two distinct power law exponents. In SME (Si m Ge n ) p heterostructures we measured μ H values generally lower than 100 cm 2 V -1 s -1 at 300 K, due to the Sb high doping level. The strong doping effect caused by Sb in SME SiGe films suggests the use of different surfactant elements or alternative growth techniques in order to fabricate Si-Ge heterostructure based devices.

Postoperative infections in prosthetic surgery still constitute a serious problem, and one that is difficult to treat, because of the occurrence of agglomerates of microbes that are resistant to immune defenses and antibiotics. In nearly all cases, removal of the prosthesis is the only possible means of solving the problem of infection. The systematic use of antibiotic prophylaxis in surgery of this sort offers advantages in terms of a reduction in the risk of infection. The authors present a personal case series relative to the strategies of perioperative antibiotic prophylaxis used in cases of hip and knee arthroplasty; we refer to 233 joint arthroplasties performed between October 1993 and April 1996. In all of the cases, perioperative prophylaxis with vancomycin chlorohydrate at a dose of 1 g i.v. 1 hour prior to surgery, and 6-8 hours after surgery was carried out. The choice of the antibiotic was based on the epidemiological knowledge of the literature and the experience on the ward.

A procedure is presented, based on the combined use of two different tomographic imaging modalities (PET and CT), aimed at the optimization of radiotherapy planning. The combined use of functional PET and anatomical CT studies allows a better definition of the tumour mass with respect to the conventional CT based approach. The proposed procedure consists in: a) spatial registration of CT and PET studies; b) contour drawing based on the combined observation of PET and CT. The set of contours thus obtained, defining optimized volumes of interest for radiotherapy, can be exported to the treatment planning system for designing the radiation beam geometry. The accuracy of the image registration was evaluated by phantom studies and found to be less than 2 pixels in plane and less than slice thickness axially, with respect to CT. The application of the procedure to the case of a patient affected by pancreatic tumour is presented, showing how the treatment planning can be improved by multimodal CT/PET information.

Air operating atomic force microscopy (AFM) has been used to study human B lymphoblastoid (Raji) cells exposed to a 50 Hz 2mT sinusoidal magnetic field (MF), up to 64 hours. A statistical analysis performed on mean height and membrane roughness of the cells showed a loss of microvilli and several modifications of the overall shape and membrane surface at increasing MF exposure.