Deflection and Friction Performance of Waste-Wooden Block Pavements

The use of waste wood for road light pavements is essential for environmental and economic sustainability.The paper investigates the mechanical performance of pavements built with waste wood elements discarded from Sardinia manufacture (Italy). Without structural value, mainly Sardinian wood is used for combustion and heating due to the characteristics of dimensional irregularity, non-homogeneity, and the presence of defects. Even small urban and forest furniture comes from foreign markets. Landscape reasons, emissions reduction, and environmental integration with the local context could encourage its use if reliable techniques are available.The study first analyzed the structural response of a portion of pavementmade with waste wood bricks (pine and Eucalyptus). Subsequently, a Finite Element simulation of the pavement has been validated with the tests' results. The experimental pavement was created with Interlocked Block Pavement (IBP) technique, using brick elements 13 x 6 x 10 cm. The behavior of the pavement was analyzed in situ with dynamic deflection tests using the Falling Weight Deflectometer test (FWD). Further tests performed in the laboratory investigated the friction of the wood pavement surface. The simulation results show that the wooden pavement elements do not differ substantially from the classic concrete IBP and HMA cracked pavement. The mean deflections are greater than 19%, while the vertical stress on the foundation layer is equivalent. As with the classic concrete IBP, the results largely depend on the bearing capacity of the substrate and the degree of interlocking.Friction tests show good values with mean values of 53 divided by 64 BPN. The most significant values were observed in the elements eucalyptus. The direction of the wood fibers also influences the results: about 3 points in the case of pine and over 7 points in the case of Eucalyptus. The study shows how the use of wood for the pavement with elements is sustainable and practicable due to the minor and low-traffic roads while also guaranteeing permeability and low-cost maintenance

Fast falling weight deflectometer method for condition assessment of rc bridges

In this paper, the use of Fast Falling Weight Deflectometer (Fast-FWD) is analyzed as a non-destructive and quick test procedure to evaluate the efficiency of short-span bridges. The FastFWD is an instrument that can produce a broadband dynamic force up to an impact value of 120 KN: The impact is constant and replicable, providing accurate action measures of bridge stiffness in a truly short period (30 ms). In this paper, a single-span reinforced concrete bridge is investigated, using the Fast-FWD. The considered bridge, approximately 12.0 m long and 15.5 m wide, was in critical condition. The bridge is in a suburban principal road near to the City of Cagliari in Sardinia (Italy), with an Annual Average Daily Traffic of 13,500 vehicles/day, and was suddenly closed, creating serious problems for urban mobility. In these conditions, the investigation through other standard techniques is time-consuming and labor intensive. For this reason, it is important to introduce methods that can be rapid, accurate and cost-efficient. In this paper, bridge stiffness values obtained during the in situ experimental campaign were compared with finite element models values. The Fast-FWD has the potential to provide engineering information that can help us to better understand bridge condition, in a rapid and cost-effective procedure

A swift approach for identifying vulnerable linear transport infrastructures in areas prone to floods and erosion

Linear transport infrastructures are essential for the socio-economic development of industrialized countries. However, adverse meteorological and hydrogeological events can result in significant economic losses.Globally, floods have the most substantial socio-economic impact. Climate Change, due to the extent of transport infrastructures over flood-prone territories, is a very important factor in worsening flood risk.The main objective of this study is to identify the sections of the hydrographic network that are susceptible to flood and erosion hazards where road infrastructures are located. The Metropolitan City of Cagliari (Sardinia, Italy) is selected as test site, due to the presence of several coastal watersheds and of a high population density.A swift methodological approach, based on already available datasets from public repositories and GIS analyses, is presented. This approach includes: i) geomorphological characterization of the hydrographic network; ii) census of stream tracts where bridges were damaged in past flood events; iii) identification of potentially critical tracts (PCT), based on similar geomorphological conditions; iv) multi-temporal satellite imagery analysis of PCT for the identification of flood-prone areas and, therefore, vulnerable road crossings.The adopted methodology has proved to be effective for the identification of vulnerable road crossings over wide portion of territories, identifying critical sites that need further investigation

REDUCING SUGAR CONTENT IN SIWALAN ROOMIE (Borassus flabellifer L) BEFORE COOKING AND LIQUID BROWN SUGAR AFTER COOKING

Sugar reduction is one of the essential macronutrients used as energy sources. High levels of sugar reduction in food can increase the sweet taste of these foodstuffs. However, the consumption of high sugar food can cause diabetes mellitus. The purpose of this study is to increase the economic value of liquid palm sugar (Borassus flabellifer L) and opportunities as a preservative in the food industry. This research used quantitative descriptive methods. The results showed that the level of sugar reduction in siwalan liquid brown sugar (Borassus flabellifer L) was 15.65%, the water content in the liquid palm sugar sample (Borassus flabellifer L) is 26.78%, and the temperature of the liquid brown sugar after cooking is 230C. The effect of heat or temperature on cooking also causes physical changes in liquid brown sugar such as caramel formation, color and flavour

Closure of an iatrogenic tracheo-esophageal fistula with bronchoscopic gluing in a mechanically ventilated adult patient

Management of acquired nonmalignant tracheo-esophageal fistula (TEF) in mechanically ventilated patients is controversial. Surgical correction is often contraindicated because the high operative risk and spontaneous closure is unlikely due to the positive pressure ventilation. We present a case of successful closure of an iatrogenic TEF in a mechanically ventilated patient with bronchoscopic application of fibrin glue. The technique may be proposed in high-risk patients as either an alternative to surgery or as a first-line attempt before surgical correction

Human breast milk cells are positive for the pioneer transcription factor ISL1

Objective: ISL1 is a pioneer transcription factor that plays important roles in cell lineage specification and differentiation, by programming the epigenome and recruiting additional regulatory factors. The aim of this study is to determine whether the human breastmilk contains ISL1-positive stem cells, and, if so, to describe the subcellular localization of ISL1. Materials and methods: Breast milk was obtained from fourteen healthy females during the first 2-6 months of lactation. Cell morphology was examined in the breast milk with the automatic ThinPrep® processor (Hologic® Inc.) in commercial Cytological ThinPrep® solution (Hologic® Inc.), followed by standard immunohistochemical staining of ISL1. Results: ISL1 had a granular diffuse cytoplasmic localization, with varying intensity of staining in both single and grouped cells. Nuclear staining was also present, as was staining of intracellular and extracellular vesicles with ISL1 antibody. Conclusions: These preliminary results suggest that ISL1 could distinguish a readily available source of putative stem cells in human breast milk. These stem cells may complete the network created between the mother and the newborn during gestation, thereby improving the efficiency of programming and reprogramming postnatal events

An experimental approach for in-situ characterization of dynamic dissipative properties of road pavements

The dissipative properties of road pavements may have beneficial effects to reduce vehicle vibrations, traffic noise, vehicles-structure dynamic interaction, and degradation of pavement materials. Assessing the dissipative capacity and the damping properties of road pavements is, therefore, of critical importance. Such assessment has been mainly conducted in recent years by laboratory-scale dynamic experiments, while little effort has been devoted to insitu tests. The latter are, in fact, cumbersome for practical reasons and typically require a more advanced data analysis when highly coupled modes of vibration are involved. Due to the heterogeneity of the road structure, classical methods are not capable of accurately estimating the road damping properties. The present study proposes an alternative experimental approach based on recording signals from accelerometers embedded in the road, which is impacted by an instrumented hammer. The data are analyzed both in the frequency and in the time domains through the combined use of stabilization diagrams and energy decay tools. Multi-mode fitting algorithms are employed to construct stabilization diagrams for the identification of resonance frequencies, while energy decay curves allow for a robust evaluation of the damping values at the identified frequencies. The effectiveness of the approach was assessed on an asphalt road structure

Real-time evaluation of the on-board comfort of standing passenger in bus transit services

Bus on-board comfort may be intended as a multidimensional concept declined according to several attributes (e.g., vibrations, the load factor, the driving style, etc.) and represents a key factor of service quality. Thus, its measurement is crucial for public transport companies as it can support for the monitoring, evaluation and implementation of specific actions to improve their services. The objective of this paper is to build a numerical scale for real-time measurement of bus on-board comfort. This is pursued integrating subjective measurements of the driving style provided by the passengers with objective ones of longitudinal and transversal accelerations data collected by Intelligent Transportation System tools. The results are very useful because they represent a contribution to establish a comfort scale in a real operational environment, as a tool to regulate the driver's behavior: each driver is in the position of real-time monitoring the quality of a bus ride regarding on-board comfort level

Immunohistochemical findings in the lungs of COVID-19 subjects: Evidence of surfactant dysregulation

OBJECTIVE: Acute respiratory distress syndrome (ARDS) is characterized by quantitative and qualitative changes in surfactant composition, leading to surfactant dysregulation with alveolar collapse and acute respiratory hypoxic failure. Recently, surfactant has been hypothesized to play a relevant role in COVID-19, representing a strong defender against SARSCoV-2 infection. The aim of our work was the study of immunohistochemical surfactant expression in the lungs of patients died following SARS-CoV-2 ARDS, in order to shed light on a possible therapeutic surfactant administration. PATIENTS AND METHODS: We investigated four patients who died due to ARDS following SARS-COV-2 infection and four patients submitted to lung biopsy, in the absence of SARSCoV-2 infection. In all 8 cases, lung specimens were immunostained with anti-surfactant protein A (SP-A) and B (SP-B). RESULTS: In control subjects, reactivity for SP-B was restricted to type II alveolar cells. Immunostaining for SP-A was observed on the surface of alveolar spaces. In the COVID-19 positive lungs, immunoreactivity for SP-B was similar to that observed in control lungs; SP-A was strongly expressed along the alveolar wall. Moreover, dense aggregates of SP-A positive material were observed in the alveolar spaces. CONCLUSIONS: Our immunohistochemical data show the dysregulation of surfactant production in COVID-19 patients, particularly regarding SP-A expression. The increased presence of SP-A in condensed masses inside alveolar spaces could invalidate the therapeutic efficacy of the treatment with exogenous surfactant