Resistencia a la fatiga térmica de la fundición vermicular

La Fundición Vermicular (FV) se caracteriza por su elevada resistencia a la fatiga térmica. Esta propiedad permite su uso para confeccionar piezas sometidas a condiciones de trabajo de ciclado térmico. En la microestructura de la FV es común la presencia de grafito nodular, lo que puede afectar las propiedades físicas de la fundición. En este contexto, la resistencia a la fatiga térmica de la FV con variados porcentajes de nódulos fue evaluada mediante ensayos de reciclado térmico entre 70 y 600ºC. Los resultados indicaron que, para una cantidad aceptable de 20% de nódulos, el número de ciclos a la primera fisura fue de 350, mientras que para porcentajes de 60 y 80% de nódulos el número de ciclos disminuyó considerablemente a 95 y 80, respectivamente.Vermicular cast iron (VCI) is characterized by its high resistance to thermal fatigue. This property allows manufacture components subjected to thermal shocks. In the microstructure of VCI is common the presence of nodular graphite, which can affects the physical properties of the material. In this context, the thermal fatigue resistance of the VCI with varying percentages of nodules was evaluated by thermal cycling tests between 70 and 600°C. The results indicated that for an acceptable amount of 20% graphite nodules, the number of cycles at the first crack was 350, while for percentages of 60 and 80% of nodules the number of cycles considerably decreased to 95 and 80, respectively

Thermal fatigue resistance of vermicular cast iron

La Fundición Vermicular (FV) se caracteriza por su elevada resistencia a la fatiga térmica. Esta propiedad permite su uso para confeccionar piezas sometidas a condiciones de trabajo de ciclado térmico. En la microestructura de la FV es común la presencia de grafito nodular, lo que puede afectar las propiedades físicas de la fundición. En este contexto, la resistencia a la fatiga térmica de la FV con variados porcentajes de nódulos fue evaluada mediante ensayos de reciclado térmico entre 70 y 600ºC. Los resultados indicaron que, para una cantidad aceptable de 20% de nódulos, el número de ciclos a la primera fisura fue de 350, mientras que para porcentajes de 60 y 80% de nódulos el número de ciclos disminuyó considerablemente a 95 y 80, respectivamente.Vermicular cast iron (VCI) is characterized by its high resistance to thermal fatigue. This property allows manufacture components subjected to thermal shocks. In the microstructure of VCI is common the presence of nodular graphite, which can affects the physical properties of the material. In this context, the thermal fatigue resistance of the VCI with varying percentages of nodules was evaluated by thermal cycling tests between 70 and 600°C. The results indicated that for an acceptable amount of 20% graphite nodules, the number of cycles at the first crack was 350, while for percentages of 60 and 80% of nodules the number of cycles considerably decreased to 95 and 80, respectively.Facultad de IngenieríaLaboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológic

Thermal fatigue resistance of vermicular cast iron

La Fundición Vermicular (FV) se caracteriza por su elevada resistencia a la fatiga térmica. Esta propiedad permite su uso para confeccionar piezas sometidas a condiciones de trabajo de ciclado térmico. En la microestructura de la FV es común la presencia de grafito nodular, lo que puede afectar las propiedades físicas de la fundición. En este contexto, la resistencia a la fatiga térmica de la FV con variados porcentajes de nódulos fue evaluada mediante ensayos de reciclado térmico entre 70 y 600ºC. Los resultados indicaron que, para una cantidad aceptable de 20% de nódulos, el número de ciclos a la primera fisura fue de 350, mientras que para porcentajes de 60 y 80% de nódulos el número de ciclos disminuyó considerablemente a 95 y 80, respectivamente.Vermicular cast iron (VCI) is characterized by its high resistance to thermal fatigue. This property allows manufacture components subjected to thermal shocks. In the microstructure of VCI is common the presence of nodular graphite, which can affects the physical properties of the material. In this context, the thermal fatigue resistance of the VCI with varying percentages of nodules was evaluated by thermal cycling tests between 70 and 600°C. The results indicated that for an acceptable amount of 20% graphite nodules, the number of cycles at the first crack was 350, while for percentages of 60 and 80% of nodules the number of cycles considerably decreased to 95 and 80, respectively.Facultad de IngenieríaLaboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológic

Thermal fatigue resistance of vermicular cast iron

La Fundición Vermicular (FV) se caracteriza por su elevada resistencia a la fatiga térmica. Esta propiedad permite su uso para confeccionar piezas sometidas a condiciones de trabajo de ciclado térmico. En la microestructura de la FV es común la presencia de grafito nodular, lo que puede afectar las propiedades físicas de la fundición. En este contexto, la resistencia a la fatiga térmica de la FV con variados porcentajes de nódulos fue evaluada mediante ensayos de reciclado térmico entre 70 y 600ºC. Los resultados indicaron que, para una cantidad aceptable de 20% de nódulos, el número de ciclos a la primera fisura fue de 350, mientras que para porcentajes de 60 y 80% de nódulos el número de ciclos disminuyó considerablemente a 95 y 80, respectivamente.Vermicular cast iron (VCI) is characterized by its high resistance to thermal fatigue. This property allows manufacture components subjected to thermal shocks. In the microstructure of VCI is common the presence of nodular graphite, which can affects the physical properties of the material. In this context, the thermal fatigue resistance of the VCI with varying percentages of nodules was evaluated by thermal cycling tests between 70 and 600°C. The results indicated that for an acceptable amount of 20% graphite nodules, the number of cycles at the first crack was 350, while for percentages of 60 and 80% of nodules the number of cycles considerably decreased to 95 and 80, respectively.Facultad de IngenieríaLaboratorio de Entrenamiento Multidisciplinario para la Investigación Tecnológic

Survey on retinopathy of prematurity (ROP) in Italy

This study aims to investigate the incidence and the relative risk factors of retinopathy of prematurity (ROP) and posterior-ROP (P-ROP): ROP in Zone I and posterior Zone II, as well as to analyze the occurrence of surgical treatment of ROP and to evaluate the short term outcome of the disease in Italy

Principal variable selection to explain grain yield variation in winter wheat from features extracted from UAV imagery

Background: Automated phenotyping technologies are continually advancing the breeding process. However, collecting various secondary traits throughout the growing season and processing massive amounts of data still take great efforts and time. Selecting a minimum number of secondary traits that have the maximum predictive power has the potential to reduce phenotyping efforts. The objective of this study was to select principal features extracted from UAV imagery and critical growth stages that contributed the most in explaining winter wheat grain yield. Five dates of multispectral images and seven dates of RGB images were collected by a UAV system during the spring growing season in 2018. Two classes of features (variables), totaling to 172 variables, were extracted for each plot from the vegetation index and plant height maps, including pixel statistics and dynamic growth rates. A parametric algorithm, LASSO regression (the least angle and shrinkage selection operator), and a non-parametric algorithm, random forest, were applied for variable selection. The regression coefficients estimated by LASSO and the permutation importance scores provided by random forest were used to determine the ten most important variables influencing grain yield from each algorithm. Results: Both selection algorithms assigned the highest importance score to the variables related with plant height around the grain filling stage. Some vegetation indices related variables were also selected by the algorithms mainly at earlier to mid growth stages and during the senescence. Compared with the yield prediction using all 172 variables derived from measured phenotypes, using the selected variables performed comparable or even better. We also noticed that the prediction accuracy on the adapted NE lines (r = 0.58–0.81) was higher than the other lines (r = 0.21–0.59) included in this study with different genetic backgrounds. Conclusions: With the ultra-high resolution plot imagery obtained by the UAS-based phenotyping we are now able to derive more features, such as the variation of plant height or vegetation indices within a plot other than just an averaged number, that are potentially very useful for the breeding purpose. However, too many features or variables can be derived in this way. The promising results from this study suggests that the selected set from those variables can have comparable prediction accuracies on the grain yield prediction than the full set of them but possibly resulting in a better allocation of efforts and resources on phenotypic data collection and processing

La falsificazione epigrafica. Questioni di metodo e casi di studio

This paper aims to reconsider the manuscript by Jacopo Valvasone (1499-1570), formerly owned by the Earl of Leicester (now British Library, Additional MS 49369), which Theodor Mommsen borrowed and inspected in 1876, just before the publication of the second part of CIL V. In the letter that he wrote to thank the Vicar and Librarian of Halkham Hall, Mommsen declared that Valvasone joined \u201cthe the long list of forgers\u201d. The analysis of forgeries in Valvasone\u2019s manuscript could show whether Mommsen was right in his opinion

A methodology for exploring biomarker – phenotype associations: application to flow cytometry data and systemic sclerosis clinical manifestations

BACKGROUND: This work seeks to develop a methodology for identifying reliable biomarkers of disease activity, progression and outcome through the identification of significant associations between high-throughput flow cytometry (FC) data and interstitial lung disease (ILD) - a systemic sclerosis (SSc, or scleroderma) clinical phenotype which is the leading cause of morbidity and mortality in SSc. A specific aim of the work involves developing a clinically useful screening tool that could yield accurate assessments of disease state such as the risk or presence of SSc-ILD, the activity of lung involvement and the likelihood to respond to therapeutic intervention. Ultimately this instrument could facilitate a refined stratification of SSc patients into clinically relevant subsets at the time of diagnosis and subsequently during the course of the disease and thus help in preventing bad outcomes from disease progression or unnecessary treatment side effects. The methods utilized in the work involve: (1) clinical and peripheral blood flow cytometry data (Immune Response In Scleroderma, IRIS) from consented patients followed at the Johns Hopkins Scleroderma Center. (2) machine learning (Conditional Random Forests - CRF) coupled with Gene Set Enrichment Analysis (GSEA) to identify subsets of FC variables that are highly effective in classifying ILD patients; and (3) stochastic simulation to design, train and validate ILD risk screening tools. RESULTS: Our hybrid analysis approach (CRF-GSEA) proved successful in predicting SSc patient ILD status with a high degree of success (>82 % correct classification in validation; 79 patients in the training data set, 40 patients in the validation data set). CONCLUSIONS: IRIS flow cytometry data provides useful information in assessing the ILD status of SSc patients. Our new approach combining Conditional Random Forests and Gene Set Enrichment Analysis was successful in identifying a subset of flow cytometry variables to create a screening tool that proved effective in correctly identifying ILD patients in the training and validation data sets. From a somewhat broader perspective, the identification of subsets of flow cytometry variables that exhibit coordinated movement (i.e., multi-variable up or down regulation) may lead to insights into possible effector pathways and thereby improve the state of knowledge of systemic sclerosis pathogenesis. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12859-015-0722-x) contains supplementary material, which is available to authorized users

Randomized trial of combination therapy in relapser or non-responder HCV patients

The combination of interferon (IFN) and ribavirin (RIBA) has efficacy in previously non-responder (NR) or relapser (REL) HCV patients. However, the effect of increased dose of IFN associated with RIBA is not known. The aim of this study was to evaluate different IFN dose in combination with RIBA in NR or REL patients.We randomised 102 patients with biopsy-proven chronic HCV hepatitis to receive either 3 or 5 MU of recombinant IFN three times a week and RIBA (1000-1200 mg/die) for 6 months and followed for additional 6 months. Patients with cirrhosis were excluded from the study. The treatment was stopped at 4 months for cases with abnormal ALT levels and HCV-RNA positivity. The patients with undetectable HCV-RNA and normal ALT at the end of the treatment were defined as complete responders (CR), and those with the same state the end of follow-up were defined as long-term responders (LTR). There were 52 non-responders and 58 relapsers to prior IFN treatment. Mean age and histological severity of liver disease was comparable in the four groups. Four patients (4%) dropped out because skin lesions or severe anaemia. A large fraction of patients (68 cases, 64 %) developed mild anaemia but therapy was not discontinued. Full follow-up data are available on 102 cases. IFN 3 MU 3 times a week End of treatment End follow-up 25 previous NR 4 CR (16%) 21 NR (84%) 4 LTR (16%) 25 previous REL 15 CR (60%) 10 NR (40%) 12 LTR (46%) IFN 5 MU 3 times a week 27 previous NR 18 CR (66%) 9 NR (33%) 12 LTR (44%) 25 previous REL 22 CR (88%) 3 NR (12%) 17 LTR (68%) There was a statistically significant difference between previous REL and NR either at the end of the treatment and of the follow-up. There was difference between previous REL subjects randomised to receive 3 or 5 MU at the end of the therapy but not at the end of the follow-up. On the contrary, in previous NR an increased dose of IFN obtained a statistically (p<0.03) improvement of responses. Interestingly, a fraction (10-40%) of previous REL became NR at the combination therapy, this could indicate the appearance of viral quasispecies or genotypes highly resistant to antiviral drugs. In conclusions, when used in combination with RIBA, 5MU of IFN is able to enhance the response rate compared with 3MU, especially in previous NR. In NR or REL cases after combination therapy, new therapeutical approaches are needed