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

CCAAT/enhancer-binding proteins are key regulators of human type two deiodinase expression in a placenta cell line

An appropriate concentration of intracellular T(3) is a critical determinant of placenta development and function and is mainly controlled by the activity of type II deiodinase (D2). The levels of this enzyme are finely regulated in different tissues by coordinated transcriptional mechanisms, which rely on dedicated promoter sequences (e.g. cAMP response element and TATA elements) that impart inducibility and tissue specificity to Dio2 mRNA expression. Here we show that CCAAT enhancer-binding proteins α and β (C/EBPα and C/EBPβ) promote Dio2 expression in the trophoblastic cell line JEG3 through a conserved CCAAT element, which is a novel key component of the Dio2 promoter code that confers tissue-specific expression of D2 in these cells. Increased C/EBPs levels potently induce Dio2 transcription, whereas their ablation results in loss of Dio2 mRNA. By measuring the activity of several deletion and point mutant promoter constructs, we have identified the functional CCAAT element responsible for this effect, which is located in close proximity to the most 5' TATA box. Notably, this newly identified sequence is highly conserved throughout the species and binds in vivo and in vitro C/EBP, indicating the relevance of this regulatory mechanism. Together, our results unveil a novel mechanism of regulation of D2 expression in a trophoblastic cell line, which may play a relevant role during placenta development

Exploring cell surface markers and cell-cell interactions of human breast milk stem cells

Background: Breakthrough studies have shown that pluripotent stem cells are present in human breast milk. The expression of pluripotency markers by breast milk cells is heterogeneous, relating to cellular hierarchy, from early-stage multi-lineage stem cells to fully differentiated mammary epithelial cells, as well as weeks of gestation and days of lactation. Design and methods: Here, we qualitatively analyze cell marker expression in freshly isolated human breast milk cells, without any manipulation that could influence protein expression. Moreover, we use electron microscopy to investigate cell-cell networks in breast milk for the first time, providing evidence of active intercellular communication between cells expressing different cellular markers. Results: The immunocytochemistry results of human breast milk cells showed positive staining in all samples for CD44, CD45, CD133, and Ki67 markers. Variable positivity was present with P63, Tβ4 and CK14 markers. No immunostaining was detected for Wt1, nestin, Nanog, OCT4, SOX2, CK5, and CD34 markers. Cells isolated from human breast milk form intercellular connections, which together create a cell-to-cell communication network. Conclusions: Cells freshly isolated form human breast milk, without particular manipulations, show heterogeneous expression of stemness markers. The studied milk staminal cells show "pluripotency" at different stages of differentiation, and are present as single cells or grouped cells. The adjacent cell interactions are evidenced by electron microscopy, which showed the formation of intercellular connections, numerous contact regions, and thin pseudopods

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

Origin–destination matrices from smartphone apps for bus networks

The knowledge of passenger flows between each origin–destination (OD) pair is a main requirement in public transport for service planning, design, operation, and monitoring, and is represented by OD matrices. Although they can be determined by traditional approaches (e.g., surveys, ride-check counts, and/or smartcard-based methods), the availability of new technologies and the proliferation of portable devices triggers an emerging interest in building OD matrices from the apps of bus operators. This research proposes the first framework for the estimation of OD matrices on transit networks by processing smartphone app call detail records (SACDRs). The framework is experimentally tested on a sample of 30 workdays of an Italian bus operator. The results are represented by easy-to-read control dashboards based on maps, which help quantify and visualise the OD matrices in the metropolitan area of Cagliari (Italy). The experimentation shows that the framework can properly estimate the number of trips for both origin and destination w.r.t. OD matrices built from household surveys: the mean absolute error is on average lower than five movements for 90% of the origins and 85% of the destinations

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

Linear transport infrastructures are essential for the socioeconomic 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

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

The role of the capping agent and nanocrystal size in photoinduced hydrogen evolution using CdTe/CdS quantum dot sensitizers

Hydrogen production via light-driven water splitting is a key process in the context of solar energy conversion. In this respect, the choice of suitable light-harvesting units appears as a major challenge, particularly as far as stability issues are concerned. In this work, we report on the use of CdTe/CdS QDs as photosensitizers for light-assisted hydrogen evolution in combination with a nickel bis(diphosphine) catalyst (1) and ascorbate as the sacrificial electron donor. QDs of different sizes (1.7-3.4 nm) and with different capping agents (MPA, MAA, and MSA) have been prepared and their performance assessed in the above-mentioned photocatalytic reaction. Detailed photophysical studies have been also accomplished to highlight the charge transfer processes relevant to the photocatalytic reaction. Hydrogen evolution is observed with remarkable efficiencies when compared to common coordination compounds like Ru(bpy)32+ (where bpy = 2,2′-bipyridine) as light-harvesting units. Furthermore, the hydrogen evolution performance under irradiation is strongly determined by the nature of the capping agent and the QD size and can be related to the concentration of the surface defects within the semiconducting nanocrystal. Overall, the present results outline how QDs featuring large quantum yields and long lifetimes are desirable to achieve sustained hydrogen evolution upon irradiation and that a precise control of the structural and photophysical properties thus appears as a major requirement towards profitable photocatalytic applications

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