9 research outputs found
LOAD BEARING STRUCTURE OF MASONRY BRIDGES
Masonry bridges are often considered arches to which the fill, retained by the spandrels, contributes as a stabilizing dead load. Recent research demonstrated that the arch-fill interaction is a fundamental contribution to the load carrying capacity of these bridges. To highlight this aspect, several tests on reduced scale models were performed but improper scaling rules introduced a bias on the results making them often unreliable. In this paper, test results on reduced scale models, according to proper scaling rules, are discussed providing an estimation of the amount of load carrying capacity increase due to the arch-fill interaction. Up to now, only a deep arch model has been tested, showing also that the classic assumption of hinge-mechanism is not fulfilled, being anticipated by compressive crushing of the materials. This raises some questions on the standard procedures for the bridge assessmen
Calibration and Reliability of the Rebound (Schmidt) Hammer Test
One of the most widely spread techniques to estimate the compressive strength of concrete is the rebound hammer test, also known as Schmidt Hammer test. In spite of a large number of scientific works trying to calibrate the test, to identify the parameters affecting its results and to estimate its reliability, the original Schmidt curve is still provided by the producers along with the hammer and is used in Structural Engineering Applications. This paper discussed an extensive research, and application, of this technique to a large number of cubes provided by the Laboratory for Building Materials of the University of Genoa, Italy, showing that several phenomena strongly affect the test: moisture content, maturity, stress state among the others. Strength estimates may differ as much as 70% if these parameters are not taken into account. Besides, several in situ investigations on existing buildings were affected by a large dispersion of data, so that we should conclude that the Rebound Hammer is unable of giving a reliable estimate of the concrete strength. This is probably due to the very limited area of the material on which the test is performed that allows also small local inhomogeneity to affect quite strongly the test. Therefore, the rebound hammer seems to be useless in the estimation of concrete compressive strength, being only a rough tool for estimating material homogeneity inside a specific concrete typ
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De novo missense variants in phosphatidylinositol kinase PIP5KIγ underlie a neurodevelopmental syndrome associated with altered phosphoinositide signaling
Phosphoinositides (PIs) are membrane phospholipids produced through the local activity of PI kinases and phosphatases that selectively add or remove phosphate groups from the inositol head group. PIs control membrane composition and play key roles in many cellular processes including actin dynamics, endosomal trafficking, autophagy, and nuclear functions. Mutations in phosphatidylinositol 4,5 bisphosphate [PI(4,5)P2] phosphatases cause a broad spectrum of neurodevelopmental disorders such as Lowe and Joubert syndromes and congenital muscular dystrophy with cataracts and intellectual disability, which are thus associated with increased levels of PI(4,5)P2. Here, we describe a neurodevelopmental disorder associated with an increase in the production of PI(4,5)P2 and with PI-signaling dysfunction. We identified three de novo heterozygous missense variants in PIP5K1C, which encodes an isoform of the phosphatidylinositol 4-phosphate 5-kinase (PIP5KIγ), in nine unrelated children exhibiting intellectual disability, developmental delay, acquired microcephaly, seizures, visual abnormalities, and dysmorphic features. We provide evidence that the PIP5K1C variants result in an increase of the endosomal PI(4,5)P2 pool, giving rise to ectopic recruitment of filamentous actin at early endosomes (EEs) that in turn causes dysfunction in EE trafficking. In addition, we generated an in vivo zebrafish model that recapitulates the disorder we describe with developmental defects affecting the forebrain, including the eyes, as well as craniofacial abnormalities, further demonstrating the pathogenic effect of the PIP5K1C variants.
We describe a neurodevelopmental disorder associated with de novo gain-of-function variants in PIP5KIγ kinase. The variants cause perturbed endosomal function resulting from increased production of phosphatidylinositol 4,5 bisphosphate and enhanced association of F-actin at endosomes. Moreover, mutant zebrafish larvae recapitulate the phenotypes observed in affected individuals from our cohort
Correction to: Changes in surgicaL behaviOrs dUring the CoviD-19 pandemic. The SICE CLOUD19 Study (Updates in Surgery, (2021), 73, 2, (731-744), 10.1007/s13304-021-01010-w)
The Collaborative Group there are two authors names are incorrect. The correct names are provided below: Paolo Pietro Bianchi and Giampaolo Formisano Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence
Correction to: Changes in surgicaL behaviOrs dUring the CoviD-19 pandemic. The SICE CLOUD19 Study (Updates in Surgery, (2021), 73, 2, (731-744), 10.1007/s13304-021-01010-w)
The Collaborative Group there are two authors names are incorrect. The correct names are provided below: Paolo Pietro Bianchi and Giampaolo Formisano Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence
Changes in surgicaL behaviOrs dUring the CoviD-19 pandemic. The SICE CLOUD19 Study
BACKGROUND: The spread of the SARS-CoV2 virus, which causes COVID-19 disease, profoundly impacted the surgical community. Recommendations have been published to manage patients needing surgery during the COVID-19 pandemic. This survey, under the aegis of the Italian Society of Endoscopic Surgery, aims to analyze how Italian surgeons have changed their practice during the pandemic.METHODS: The authors designed an online survey that was circulated for completion to the Italian departments of general surgery registered in the Italian Ministry of Health database in December 2020. Questions were divided into three sections: hospital organization, screening policies, and safety profile of the surgical operation. The investigation periods were divided into the Italian pandemic phases I (March-May 2020), II (June-September 2020), and III (October-December 2020).RESULTS: Of 447 invited departments, 226 answered the survey. Most hospitals were treating both COVID-19-positive and -negative patients. The reduction in effective beds dedicated to surgical activity was significant, affecting 59% of the responding units. 12.4% of the respondents in phase I, 2.6% in phase II, and 7.7% in phase III reported that their surgical unit had been closed. 51.4%, 23.5%, and 47.8% of the respondents had at least one colleague reassigned to non-surgical COVID-19 activities during the three phases. There has been a reduction in elective (>200 procedures: 2.1%, 20.6% and 9.9% in the three phases, respectively) and emergency (<20 procedures: 43.3%, 27.1%, 36.5% in the three phases, respectively) surgical activity. The use of laparoscopy also had a setback in phase I (25.8% performed less than 20% of elective procedures through laparoscopy). 60.6% of the respondents used a smoke evacuation device during laparoscopy in phase I, 61.6% in phase II, and 64.2% in phase III. Almost all responders (82.8% vs. 93.2% vs. 92.7%) in each analyzed period did not modify or reduce the use of high-energy devices.CONCLUSION: This survey offers three faithful snapshots of how the surgical community has reacted to the COVID-19 pandemic during its three phases. The significant reduction in surgical activity indicates that better health policies and more evidence-based guidelines are needed to make up for lost time and surgery not performed during the pandemic
Changes in surgicaL behaviOrs dUring the CoviD-19 pandemic. The SICE CLOUD19 Study
Background: The spread of the SARS-CoV2 virus, which causes COVID-19 disease, profoundly impacted the surgical community. Recommendations have been published to manage patients needing surgery during the COVID-19 pandemic. This survey, under the aegis of the Italian Society of Endoscopic Surgery, aims to analyze how Italian surgeons have changed their practice during the pandemic. Methods: The authors designed an online survey that was circulated for completion to the Italian departments of general surgery registered in the Italian Ministry of Health database in December 2020. Questions were divided into three sections: hospital organization, screening policies, and safety profile of the surgical operation. The investigation periods were divided into the Italian pandemic phases I (March\u2013May 2020), II (June\u2013September 2020), and III (October\u2013December 2020). Results: Of 447 invited departments, 226 answered the survey. Most hospitals were treating both COVID-19-positive and -negative patients. The reduction in effective beds dedicated to surgical activity was significant, affecting 59% of the responding units. 12.4% of the respondents in phase I, 2.6% in phase II, and 7.7% in phase III reported that their surgical unit had been closed. 51.4%, 23.5%, and 47.8% of the respondents had at least one colleague reassigned to non-surgical COVID-19 activities during the three phases. There has been a reduction in elective (> 200 procedures: 2.1%, 20.6% and 9.9% in the three phases, respectively) and emergency (< 20 procedures: 43.3%, 27.1%, 36.5% in the three phases, respectively) surgical activity. The use of laparoscopy also had a setback in phase I (25.8% performed less than 20% of elective procedures through laparoscopy). 60.6% of the respondents used a smoke evacuation device during laparoscopy in phase I, 61.6% in phase II, and 64.2% in phase III. Almost all responders (82.8% vs. 93.2% vs. 92.7%) in each analyzed period did not modify or reduce the use of high-energy devices. Conclusion: This survey offers three faithful snapshots of how the surgical community has reacted to the COVID-19 pandemic during its three phases. The significant reduction in surgical activity indicates that better health policies and more evidence-based guidelines are needed to make up for lost time and surgery not performed during the pandemic