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Ferritic ductile iron (DI) GJS 400 and high-silicon strengthened ductile irons (HSSDIs) with 3.5 and 4.5 wt% of silicon contents were produced with different cooling rates, and the microstructures were analyzed to find the main microstructure parameters. The Y-blocks GJS 400 presented good nodularity, while the heavy section GJS 400 presented some graphite degeneracy with a lower nodularity. The 3.5 wt% HSSDI shown a good nodularity, while with increasing silicon content to 4.5 wt%, significant graphite degeneracy occurred with the appearance of chunky graphite. Samples were tensile tested and the tensile data were analyzed through the physical-based constitutive Voce equation, and the Voce parameters were plotted to produce a matrix assessment diagram (MAD). Y-blocks and heavy section GJS 400 data lied on two distinct lines in MAD, and they had, however, positive and negative intercepts which meant indeed two contradictory plastic behaviors. The intercept of the best fitting line of the GJS 400 Y-blocks data was positive and so consistent with the physical meaning of Voce equation, while the intercept of the best fitting line of the GJS 400 heavy section data was negative, which meant an unexpected opposite plastic behavior. Same behavior was reported for the investigated HSSDIs, resulting in positive intercept of the best fitting line in MAD for the 3.5 wt% HSSDI data and negative intercept for the 4.5 wt% HSSDI data. The uniform strain energy density (SEDU) that is the area below the tensile flow curve up to the uniform strain, i.e., the strain where necking begins, was also investigated. SEDU resulted to be almost constant for all the GJS 400 Y-blocks tensile flow curves and 3.5 wt% HSSDI, which was typical of a sound material, while in GJS 400 heavy section and 4.5 wt% HSSDI, SEDU changed significantly in a systematic way, indicating that metallurgical defects had affected the plastic behavior. So it was concluded that in the MAD the best fitting line of the tensile data with positive intercept was a possible indication of the material soundness, while the negative intercept was indication of defected material. The results suggested that the MAD analysis produced from tensile Voce parameters can be a useful and easy tool for industry not only to classify the production routes of DIs (Si content mainly and heat treatments), but also to identify possible microstructure poorness within a single DI grade. [ABSTRACT FROM AUTHOR]

The formulation of a probability-stress-life (P-S-N) curve is a necessary step beyond the basic S-N relation when dealing with reliability. This paper presents a model, relevant to materials that exhibits a fatigue limit, which considers the number of cycles to failure and the occurrence of the failure itself as statistically independent events, described with different distributions and/or different degree of scatter. Combining these two as a parallel system leads to the proposed model. In the case where the S-N relation is a Basquin's law, the formulations of the probability density function, cumulative distribution function, quantiles, parameter and quantile confidence interval are presented in a procedure that allows practically any testing strategy. The result is a flexible model combined with the tools that deliver a wide range of information needed in the design phase. Finally, an extension to include static strength and applicability to fatigue crack growth and defects-based fatigue approach are presented. [ABSTRACT FROM AUTHOR]

We present a retrospective study to evaluate safety and effectiveness of ultrasound (US)-guided tattooing with charcoal of suspicious laterocervical lymph nodes. When an open biopsy of a laterocervical lymph node is needed, the choice of the lymph node to excise and examine is fundamental to avoid rebiopsy. Surgeons tend to choose the most surgical approachable enlarged lymph node that does not always correspond to the one with worst echographic aspect. We present 16 cases of patients with laterocervical adenopathy with inconclusive or non-adequate results at fine needle aspiration cytology addressed to open biopsy. Those patients underwent US-guided preoperative injection of a charcoal suspension inside the lymph node to excise to mark it, and then excisional biopsy was performed. Sixteen marked lesions (100 %) were detected intraoperatively and dissected. The injected charcoal was detected intraoperatively in all cases. In 14 patients (87, 5 %) it was inside the lesion; in two cases (12, 5 %), the charcoal suspension was found in the tissues above the lesion. The procedure was well tolerated in all cases. No major procedure-related complications were encountered. US-guided charcoal tattooing is a new, safe, well-tolerated, and easy-to-perform technique for the marking of US suspicious laterocervical lymph nodes. This preliminary study shows a high technical success rate (76 %) and high percentage of intraoperative detection of marked lesions (100 %) with a low rate of complications. [ABSTRACT FROM AUTHOR]

The critical plane calculation for multiaxial damage assessment is often a demanding task, particularly for large FEM models of real components. Anyway, in actual engineering requests, sometime, it is possible to take advantage of the specific properties of the investigated case. This paper deals with the problem of a mechanical component loaded by multiple, but "time-separated", multiaxial external loads. The specific material damage is dependent from the max principal stress variation with a significant mean stress sensitivity too. A specifically fitted procedure was developed for a fast computation, at each node of a large FEM model, of the direction undergoing the maximum fatigue damage; the procedure is defined according to an effective stress definition based on the max principal stress amplitude and mean value. The procedure is presented in a general form, applicable to the similar cases. [ABSTRACT FROM AUTHOR]

Background: We investigated the value of magnetic resonance imaging (MRI) in the evaluation of sex-reassignment surgery in male-to-female transsexual patients.Methods: Ten male-to-female transsexual patients who underwent sex-reassignment surgery with inversion of combined penile and scrotal skin flaps for vaginoplasty were examined after surgery with MRI. Turbo spin-echo T2-weighted and spin-echo T1-weighted images were obtained in sagittal, coronal, and axial planes with a 1.5-T superconductive magnet. Images were acquired with and without an inflatable silicon vaginal tutor. The following parameters were evaluated: neovaginal depth, neovaginal inclination in the sagittal plane, presence of remnants of the corpus spongiosum and corpora cavernosa, and thickness of the rectovaginal septum.Results: The average neovaginal depth was 7.9 cm (range = 5-10 cm). The neovagina had a correct oblique inclination in the sagittal plane in four patients, no inclination in five, and an incorrect inclination in one. In seven patients, MRI showed remnants of the corpora cavernosa and/or of the corpus spongiosum; in three patients, no remnants were detected. The average thickness of the rectovaginal septum was 4 mm (range = 3-6 mm).Conclusion: MRI allows a detailed assessment of the pelvic anatomy after genital reconfiguration and provides information that can help the surgeon to adopt the most correct surgical approach. [ABSTRACT FROM AUTHOR]

Non-ionic dimers induce less diuresis than non-ionic monomers, resulting in increased opacification of the urinary tract in intravenous urography. This trial compared the diagnostic efficacy of iodixanol and iopromide in patients with macroscopic haematuria. One hundred consecutive patients with normal renal function and macroscopic haematuria entered a double blind, comparative, randomised, parallel trial. Contrast media were given with bolus injection in doses of 300 mgI/kg b.w. Radiographs were blindly evaluated by three radiologists who analysed different parameters (calyceal density and filling, papillary blush detection, delineation of collecting ducts, renal pelvis opacification, visualisation of ureters, bladder density, bladder distention) and estimated the diagnostic confidence (whether abnormal findings were definitely absent, probably absent, doubtful, probably present or certainly present). Radiological diagnoses were compared with final diagnoses. Results were summarised as the ratio of the odds of having a worse performance of iopromide vs iodixanol. Iodixanol showed a significantly better calyceal density and filling [odds ratio (OR): 1.96; 95% confidence interval (CI): 1.60-2.41], a significantly better pelvis opacification (OR 2.91; CI 2.02-4.18) and a significantly more frequent papillary blush detection (OR 1.95; CI 1.29-2.95). Iopromide showed a significantly better ureteral visualisation (OR 0.67; CI 0.48-0.92) and a significantly higher bladder distention (OR 0.59; CI 0.36-0.99). Iodixanol allowed a significantly higher diagnostic confidence as to calyceal evaluation (OR 1.35; CI 1.01-1.79). No significant differences were found with regard to other parameters. The results confirmed theoretical expectations. The higher opacification provided by iodixanol allowed better results and a higher diagnostic confidence in the upper excretory pathway. [ABSTRACT FROM AUTHOR]

Objectives: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.Materials and methods: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.Results: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.Conclusion: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.Clinical relevance statement: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.Key Points: To investigate preoperative MRI evaluation of the features of the mylohyoid muscle (MM) predictive of its infiltration in oral squamous cell carcinoma (OSCC) treatment planning, defining the most appropriate sequences to study its deep extension into the floor of the mouth (FOM).We applied a 7-point score to retrospectively evaluate preoperative imaging of patients who underwent surgery for OSCC over 11 years. The results were compared with histopathological findings using Spearman’s rank coefficient. Receiver operating characteristic curves were employed to assess the score’s ability to predict MM infiltration, determining optimal thresholds for sensitivity, specificity, and predictive values. The Mann–Whitney U-test confirmed that infiltration judgments did not overlap around this threshold. Cohen’s K statistical coefficient was used to evaluate the interobserver agreement.Fifty-two patients (mean age 66.4 ± 11.9 years, 36 men) were evaluated. Histopathological examination found MM infiltration in 21% of cases (n = 11), with 90% classified in the highest Score categories. A score > 4 proved to be the best cut-off for predicting the risk of MM infiltration, with a sensitivity of 91% (CI: 0.57–0.99), specificity 61% (CI: 0.45–0.76), PPV 38% (CI: 0.21–0.59), and NPV 96% (CI: 0.78–0.99). At the subsequent single-sequence assessment, the TSE-T2wi had the highest diagnostic accuracy, with sensitivity 90% (CI: 0.57–0.99), specificity 70% (CI: 0.53–0.82), PPV 45% (CI: 0.25–0.67), and NPV 96% (CI: 0.80–0.99).The 7-point score is a promising predictor of safe surgical margins for MM in OSCC treatment, with the particular benefit of T2-weighted sequences.Our scoring system for tumor infiltration of MM, which is easy to use even for less experienced radiologists, allows for uniformity in radiological language, thereby ensuring crucial preoperative information for the surgeon.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor.The relationship of the MM to an oral lesion may impact surgical planning.As the score increases, there is a greater incidence of infiltration in the MM.Our score system improves radiologists’ reporting for MM involvement by tumor. [ABSTRACT FROM AUTHOR]

A novel approach to the modelling and simulation of the industrial compaction process of ceramic powders is proposed, based on a combination of: (i) continuum mechanics modelling of the constitutive response of the material; (ii) finite element discretization and computer implementation of the mechanical model; (iii) parametric identification by a multi-objective optimization of simulated experimental tests. The capabilities of the proposed approach are highlighted through computer simulations of realistic industrial compaction processes, namely, the forming of an axisymmetric tablet and of a three-dimensional ceramic tile. The presented methods and the pointed out results pave the way for the introduction of so-called virtual prototyping into the industrial practice of ceramic forming processes. [ABSTRACT FROM AUTHOR]

The paper presents new experimental multiaxial fatigue data on cast iron. Several sets of specimens, taken from a real large component, have been tested under uniaxial and biaxial, tensile and torsional loading; in-phase and out-of-phase combined loadings have also been considered. The obtained results have been compared with similar experimental data taken from the literature, and the tested material has shown high sensibility to the mean value of shear stress under torsional loading, as well as dependence on the mean value of tensile stress under tensile loading. The most suitable fatigue criterion should be related to the larger principal stress variation. The materials show an unusual sensibility to the out-phase loading. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The aim of this study was to design, deliver and evaluate an e-learning teaching programme for post-graduate radiodiagnostics training that would involve various post-graduate schools throughout Italy. Materials and methods: All of the Directors of Italian post-graduate schools of radiodiagnostics were sent an e-mail on 27 September 2010 informing them of our willingness to set up an e-learning project for the academic year 2010–2011 in the form of single-subject teaching seminars. The proposed subjects were the semeiotics of the various organs and apparatuses in the context of “Urgent/Emergency Pathology”. After having received registrations, a calendar of lessons was planned to be held between 10 November 2010 and 12 October 2011. The validity of the project was tested by means of a multiple-choice questionnaire covering the technical and didactic quality of the entire project, to be completed by the students. Results: Fifty-one percent of the universities in Italy participated in the project: Trieste, Udine, Verona, Milan-Bicocca, Novara, Varese, Genoa, Sassari, Rome Campus, the Catholic University of Rome, Chieti, Foggia, Catania, Modena, Florence, Palermo, Bologna, Pavia, Parma and Ferrara. The lessons were attended by a total of 10,261 post-graduate medical students, for an average of 513.1 students per lesson. Seventy percent of the students judged the didactic content “excellent”, 25% “good”, and 5% “satisfactory”; none said it was unsatisfactory. In terms of visual quality (particularly the details of the radiological images proposed in the form of slides and/or video clips), 73% judged it “excellent”, 20% “good”, 6% “satisfactory”, and 1% “poor”. The audio quality was judged “excellent” by 71%, “good” by 22%, “satisfactory” by 6% and “poor” by 1%. In relation to judgement of audio and video quality, it has to be underlined that this was greatly affected by the hardware/software configuration and the band speed and technology of the Internet connection. Conclusions: Technological evolution is overcoming all barriers, and technology is also having a positive impact on the approach to teaching. Our multicentre teaching experience merits the following considerations: the quality of the teaching product was certified by the students’ judgements of its didactic content and the quality of reception; the economic cost of the teaching had a minimal impact on the post-graduate schools (€ 18 per lesson). In terms of breaking down national barriers, it is to be hoped that the coordination and integration of diagnostic imaging e-learning projects, with the participation of post-graduate schools in different European countries, can be developed not only in a spirit of “cultural sharing” and the exchange of teaching experiences. [Copyright &y& Elsevier]

Background: We describe different possible enhancement patterns in liver hemangiomas with atypical appearance on baseline ultrasound after microbubble-based contrast agent injection. Methods: From a series of 253 consecutive lesions that were indeterminate on baseline ultrasound and then scanned after injection of air-filled microbubble contrast agent, 65 focal liver lesions were retrospectively selected on the basis of a diagnosis of liver hemangioma on multiphase contrast-enhanced computed tomography (n = 23), magnetic resonance imaging (n = 27), or histology (n = 15). Each lesion was scanned during arterial phase (30 s after microbubble injection) and late phase (5 min after injection). On-site sonologists performed retrospective assessment of contrast-enhancement patterns by consensus. Results: Centripetal fill-in preceded (n = 50) or not preceded (n = 3) by peripheral nodular/rim-like enhancement was the prevalently observed contrast-enhancement pattern, equivalent to the typical enhancement pattern of liver hemangiomas on contrast-enhanced computed tomography or magnetic resonance imaging. In the remaining lesions, additional enhancement patterns (diffuse contrast enhancement with rapid fill-in and a late hyper-isoechoic appearance, n = 6; peripheral nodular enhancement with a late hypoechoic appearance, n = 3; or persistent heterogeneous and hyperechoic appearance, n = 3) were observed. Conclusion: Different contrast-enhancement patterns are possible in atypical liver hemangiomas after microbubble injection. Typical centripetal fill-in is the prevalent pattern and its evidence allows diagnosis. [ABSTRACT FROM AUTHOR]

Nowadays, the surgical treatment of male-to-female transsexuals is not rare, but few studies have reported on postoperative results. The aim of this study was to determine the role of magnetic resonance imaging (MRI) in the evaluation of the results of sex reassignment surgery (SRS) in male-to-female transsexual patients. Ten such patients (median age 28 years, range 21-47), who had undergone SRS using an inversion of combined penile and scrotal skin flaps for vaginoplasty, were examined with MRI after the operation. Turbo spin-echo T2-weighted and spin-echo T1-weighted images were obtained on sagittal, coronal, and axial planes with a 1.5 T superconducting magnet. The images were acquired on the sagittal, coronal and axial planes, by using TSE T2 weighted and SG T1 weighted images. MRI was performed within 2 weeks after the operation in six patients and after 1 year in the other four. In all cases, the images were obtained with and without an inflatable silicon vaginal tutor. The average neovaginal depth was 7.9 cm (range 6-10 cm). In four patients, MRI showed the presence of cavernosal rests, and in two there were remnants of the corpus spongiosus. In another patient, an abnormal anterior inclination of the neovagina was present. The average distance of the recto-vaginal septum was 4 mm (range 3-6 mm). No major complications were noted. Our study allowed not only a detailed assessment of the pelvic anatomy after genital reconfiguration, but also provided valuable information on possible complications. [ABSTRACT FROM AUTHOR]

• A multi-scale model for clusters of degenerated graphite in cast iron is proposed. • At the microscale, graphite particles inside the cluster are seen as elliptical pores. • At the mesoscale, graphite clusters are viewed as equivalent elliptical inclusions. • For the equivalent elastic properties, the Mori-Tanaka's estimate is used. • The accuracy of the model is numerically verified by a FE analysis. We develop a hierarchical model for the description of the stress state inside a cluster of degenerated graphite in spheroidal cast iron. The model is based on the following simplifying assumptions: at the microscale, the graphite particles are viewed as elliptical pores; at the mesoscale, clusters of graphite particles are modeled as elliptical inclusions made of an equivalent porous elastic material in plane strain. To calculate the equivalent elastic properties of the porous material, we adopt the Mori-Tanaka's estimate. The accuracy of the model has been numerically verified by comparing the results of the model with FE simulations at three different levels: at the microscale, at the mesoscale, and coupling at the two scales. The model allows to study the effect of graphite microstructure on the average stress distribution inside the cluster. [ABSTRACT FROM AUTHOR]