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The fused deposition modeling (FDM) process, an extrusion-based 3D printing technology, enables the manufacture of complex geometrical elements. This technology employs diverse materials, including thermoplastic polymers and composites as well as recycled resins to encourage sustainable growth. FDM is used in a variety of industrial fields, including automotive, biomedical, and textiles, as a rapid prototyping method to reduce costs and shorten production time, or to develop items with detailed designs and high precision. The main phases of this technology include the feeding of solid filament into a molten chamber, capillary flow of a non-Newtonian fluid through a nozzle, layer deposition on the support base, and layer-to-layer adhesion. The viscoelastic properties of processed materials are essential in each of the FDM steps: (i) predicting the printability of the melted material during FDM extrusion and ensuring a continuous flow across the nozzle; (ii) controlling the deposition process of the molten filament on the print bed and avoiding fast material leakage and loss of precision in the molded part; and (iii) ensuring layer adhesion in the subsequent consolidation phase. Regarding this framework, this work aimed to collect knowledge on FDM extrusion and on different types of rheological properties in order to forecast the performance of thermoplastics. [ABSTRACT FROM AUTHOR]

The use of Building Information Modelling (BIM) is becoming increasingly adopted worldwide to support the creation and management of digital environments in which physical and functional features of a facility are modelled. Due to its characteristic flexibility and interoperability, it rapidly extends beyond the boundaries of applications for which it was originally conceived, thus being implemented in other contexts such as the infrastructure sector. Indeed, during each phase of the construction process for building a linear infrastructure, a suitable design of a traffic control plan to optimising traffic flows proves crucial, both for drivers and builders. In this context, there arises the need to perform a comprehensive analysis, combining infrastructure design and building issues with transportation theory principles. For this purpose, the paper proposes a comparative analysis of two different approaches relying on BIM-based tools, namely integrated (i.e., BIM environments with an in-built module for transport simulation tasks) and an interfaceable solution (i.e., BIM environments offering a customised interface for external mobility simulation software). Specifically, after an overview of the issues involved, the two solutions analysed are customised according to the software packages adopted, and a numerical application is carried out. The goal of the paper is to perform a preliminary analysis on the potential of such frameworks by means of comparative evaluation aimed at identifying pros and cons of the two approaches, as well as the best field of application, according to the effort required from the designer, the degree of flexibility offered, and the target pursued., Author(s): Marilisa Botte [1]; Amedeo Zampi [1]; Cristina Oreto [1]; Luca D'Acierno (corresponding author) [1] 1. Introduction With the advent of Information and Communication Technologies (ICTs), cities have become increasingly [...]

We evaluated the polyphenol content and the α-glucosidase activity exhibited by different monofloral honeys of Italian origin. Their capacity to act on different pathogenic (Acinetobacter baumannii, Escherichia coli, Listeria monocytogenes, Pseudomonas aeruginosa, and Staphylococcus aureus) as well as probiotic bacteria (Lacticaseibacillus casei, Lactobacillus acidophilus, Lactiplantibacillus plantarum, Lactobacillus gasseri, and Lacticaseibacillus rhamnosus) was also assessed. Total polyphenols varied between 110.46 μg/g of fresh product (rhododendron honey) and 552.29 μg/g of fresh product (strawberry tree honey). Such result did not correspond to a parallel inhibitory α-glycosidase activity that, in each case was never higher than 33 μg/mL. Honeys were differently capable to fight the biofilm formation of the pathogens (inhibition up to 93.27%); they inhibited the in vitro adhesive process (inhibition up to 84.27%), and acted on mature biofilm (with values up to 76.64%). Their effect on bacterial metabolism was different too. Honeys were ineffective to inhibit E. coli mature biofilm nor to act on its metabolism. The action of the honey on probiotic strains seemed almost always stimulate their growth. Thus, these monofloral honeys might exhibit effects on human health and act positively as prebiotics.

In this paper, we study the effect of the addition of wood flour as a filler in a recycled polyethylene (r-PE) in view of its potential applications in 3D printing. The composites, prepared by melt mixing, are characterized with torque measurements performed during the compounding, dynamic rotational rheology, and infrared spectroscopy. Data show that the introduction of wood results in increased viscosity and in sensible viscous heating during the compounding. The r-PE appear to be stable at temperatures up to 180 °C while at higher temperatures the material shows a rheological response characterized by time-increasing viscoelastic moduli that suggests a thermal degradation governed by crosslinking reactions. The compounds (with wood loading up to 50% in wt.) also shows thermal stability at temperatures up to 180 °C. The viscoelastic behavior and the infrared spectra of the r-PE matrix suggests the presence of branches in the macromolecular structure due to the process. Although the addition of wood particles determines increased viscoelastic moduli, a solid-like viscoelastic response is not shown even for the highest wood concentrations. This behavior, due to a poor compatibility and weak interfacial adhesion between the two phases, is however promising in view of common processing technologies as extrusion or injection molding.

Abstract Congenital hypogonadotropic hypogonadism (CHH) is a rare genetic form of isolated gonadotropin‐releasing hormone (GnRH) deficiency caused by mutations in > 30 genes. Fibroblast growth factor receptor 1 (FGFR1) is the most frequently mutated gene in CHH and is implicated in GnRH neuron development and maintenance. We note that a CHH FGFR1 mutation (p.L342S) decreases signaling of the metabolic regulator FGF21 by impairing the association of FGFR1 with β‐Klotho (KLB), the obligate co‐receptor for FGF21. We thus hypothesized that the metabolic FGF21/KLB/FGFR1 pathway is involved in CHH. Genetic screening of 334 CHH patients identified seven heterozygous loss‐of‐function KLB mutations in 13 patients (4%). Most patients with KLB mutations (9/13) exhibited metabolic defects. In mice, lack of Klb led to delayed puberty, altered estrous cyclicity, and subfertility due to a hypothalamic defect associated with inability of GnRH neurons to release GnRH in response to FGF21. Peripheral FGF21 administration could indeed reach GnRH neurons through circumventricular organs in the hypothalamus. We conclude that FGF21/KLB/FGFR1 signaling plays an essential role in GnRH biology, potentially linking metabolism with reproduction.

The aim of the present research is to develop an instrument able to adequately support the conservation process by means of a twofold approach, based on both BIM environment and ontology formalisation. Although BIM has been successfully experimented within AEC (Architecture Engineering Construction) field, it has showed many drawbacks for architectural heritage. To cope with unicity and more generally complexity of ancient buildings, applications so far developed have shown to poorly adapt BIM to conservation design with unsatisfactory results (Dore, Murphy 2013; Carrara 2014). In order to combine achievements reached within AEC through BIM environment (design control and management) with an appropriate, semantically enriched and flexible The presented model has at its core a knowledge base developed through information ontologies and oriented around the formalization and computability of all the knowledge necessary for the full comprehension of the object of architectural heritage an its conservation. Such a knowledge representation is worked out upon conceptual categories defined above all within architectural criticism and conservation scope. The present paper aims at further extending the scope of conceptual modelling within cultural heritage conservation already formalized by the model. A special focus is directed on decay analysis and surfaces conservation project.

Abstract The importance of a mobility system based on railway technology as the backbone of public transport is now widely acknowledged. Indeed, rail systems are green, high performing, smart and able to ensure a high degree of safety. Therefore, modal split should be steered towards rail transport by increasing the attractiveness of this transport mode. In this context, a key element is represented by the timetabling design phase, which must aim to guarantee an appropriate degree of robustness of rail operations in order to ensure a high degree of system reliability and increase service quality. A crucial factor in the task of timetabling entails evaluating dwell times at stations. The innovative feature of this paper is the analytical definition of dwell times as flow dependent. Our proposal is based on estimating dwell times according to the crowding level at platforms and related interaction between passengers and the rail service in terms of user behaviour when a train arrives. An application in the case of a real metro system is provided in order to show the feasibility of the proposed approach.

Enduring an arduous quest is an important component of the knightly code of honor. In the courtly love tradition of the Middle Ages, embarking on this quest and prevailing over its daunting obstacles epitomized the essential requirements for courtly love; that is, in overcoming those obstacles, a knight gained the spiritual value and honor that made him worthy of love. Accordingly, the attainment of spiritual value and honor opened a critical door: it allowed the knight to win over his lady and thus fulfill his carnal desires. Lancelot, for example, the main character in Chrétien de Troyes’s The Knight of the Cart, meets all the quintessential requirements implicit in the courtly love tradition when he embarks on his quest for Guinevere. I will argue in this paper that, by the late fifteenth century, Spanish writer Fernando de Rojas, in his seminal work La Celestina (1499), reclaims this tradition’s generic and distinguishing principles (a tradition called amor cortés in Spanish) in order to set up a specific path of inference for the reader. His reader, clearly recognizing the courtly love scantlings, will assign specific meanings to the work that correspond to a set of possible, courtly-love inspired conclusions, to which he/she is being led. This design is evident from the first lines of the work: when Calisto sees Melibea in her garden and love enters his soul just from the sight of her, the structure of the language and the emotive meaning it creates for the reader is, unmistakably, that of courtly love. But the reasoning texture soon becomes more complex, as the semantic information provided by other characters (who are not courtly lovers and, interestingly, often whisper to themselves or to each other in asides) begins to undermine the reader’s path of inference, forging an alternate dimension of meaning where the work’s language becomes contested ground, the instrument of credible agents holding pragmatic systems of belief and opposing values. In other words, for the reader, the initial prescriptive dimension of unequivocal meaning anticipated by generic courtly love language and content is challenged and overwhelmed by a subversive pattern of reasoning, one based upon real-life needs, interests and the profit motive.

Congenital hypogonadotropic hypogonadism (CHH) is a condition characterized by absent puberty and infertility due to gonadotropin releasing hormone (GnRH) deficiency, which is often associated with anosmia (Kallmann syndrome, KS). We identified loss-of-function heterozygous mutations in anti-Müllerian hormone (AMH) and its receptor, AMHR2, in 3% of CHH probands using whole-exome sequencing. We showed that during embryonic development, AMH is expressed in migratory GnRH neurons in both mouse and human fetuses and unconvered a novel function of AMH as a pro-motility factor for GnRH neurons. Pathohistological analysis of Amhr2-deficient mice showed abnormal development of the peripheral olfactory system and defective embryonic migration of the neuroendocrine GnRH cells to the basal forebrain, which results in reduced fertility in adults. Our findings highlight a novel role for AMH in the development and function of GnRH neurons and indicate that AMH signaling insufficiency contributes to the pathogenesis of CHH in humans.

e1299-Hepatocellular carcinoma and non-alcoholic fatty liver disease-a dangerous liaisonLiver cancer is one of the most frequent malignancies in the world, and its incidence rates are on the rise. Due to the global epidemic of metabolic syndrome, the incidence of hepatocellular carcinoma (HCC) secondary to non-alcoholic fatty liver disease (NAFLD) is increasing, contrary to viral forms. Characteristically NAFLD-related HCCs tend to occur at the earlier stages of liver disease, while often the diagnosis of neoplasia occurs later. They also affect an averagely older population, generally with a significantly higher number of co-morbidities. For these reasons, curative treatments are seldom applicable. Therefore, this work aims to illustrate the current state of knowledge on the NAFLD-related HCC and to underline the known pathogenetic mechanisms.

Since pain perception is highly subjective and culturally mediated, its objective evaluation remains difficult. Nevertheless, pain measurement should ideally be a part of the assessment of patients in order to plan adequate pain relief. Several scales have been proposed for pain measurement, being the numerical rating scale (NRS) the most widely used, often at triage time. NRS have demonstrated acceptable reliability and validity, in post-operative medicine and in oncologic pain, but data in the Emergency Departments (EDs) are poor. The aim of this study is to evaluate the Emergency Nurses’ (ENs) perception about the reliability of NRS in the triage process. A questionnaire based on 11 items was designed and subsequently administered to a large number of ENs in several EDs in Northern and Central Italy. 301 questionnaires were filled out and returned. The majority declares using NRS scale to measure pain (item 2, mode = 4, mean = 3.8), and attributing priority code based on NRS value (item 3, mode = 4, mean = 3.4). In general, triage nurses believe that NRS is only indicative and that their judgement matters (item 4, mode = 4, mean = 3.2). The vast majority of triage nurses do believe that the patients will indicate a fake higher NRS value with the aim to get a more urgent code (item 5, mode = 5, mean = 4), while only a small minority expects that patients would underestimate their NRS for fear of penalizing more urgent patients. Very few believe that such scale underestimates the patients’ condition, while the majority is ambivalent about whether such scale overestimates it. In conclusion, NRS confirms to be a potentially valuable tool for pain evaluation at triage time, but many nurses express some doubts on its reliability, and will attribute the triage code mainly basing on their own judgement.

Commercial waterborne polyurethane (PU) dispersions, different in chemistry and selected on the basis of eco-friendly components, have been applied to a common polypropylene (PP)-based woven fabric. Impregnation has been chosen as a textile treatment for improving the features of basic technical textiles in light of potential applicability in luggage and bag production. The effect of drying method, performed under conditions achieved by varying the process temperature and pressure, on the features of the treated textiles, has been verified. The prepared specimens were characterized in terms of mechanical behavior (tensile, tear and abrasion resistance) and water resistance (surface wettability and hydrostatic pressure throughout the treated textiles). The experimental results suggest an incremental improvement of the tensile features for all the investigated specimens. For tear strength, no augmentation compared to that of the neat textile, could be verified as a consequence of polyurethane treatment. Remarkable improvements of abrasion resistance were displayed for all the impregnated PP textiles. Benefits in water resistance could be attributed to the presence of hydrophobic PU in the textile weaving of the PP samples. The ultimate improvement in water resistance was dependent on drying conditions.

The purpose of this research was to better understand the potential degradation effects of bioderived thermoplastic polymers during fused deposition modeling (FDM). Commercially available filaments made from virgin and recycled polylactic acid (PLA) (named PLA-1 and PLA-2, respectively), as well as a wood flour/PLA composite (PLA-3), were considered. Pre-optimized conditions, satisfying the printing quality of 3D final products, at an extruder temperature of 210 °C, were used to realize samples. The main characterization techniques, were dynamic rotational rheology (in time sweep mode) and infrared spectroscopy (in attenuated total reflectance mode). These methods allowed to verify molecular modifications, occurring in the polymer structure during the 3D printing process. The storage and loss modulus, and complex viscosity over time were presented for both neat and printed specimens. A comparison between the properties of printed and unprocessed materials revealed a decrease in rheological parameters over time as well as a loss in absorbance intensity for typical absorption bands. The viscosity values of PLA-1 and PLA-2 were found to be strongly unstable, with a significant decreasing trend over time. The experimental data were modeled using an exponential decay law, and the original decline was attributed primarily to the interaction of high temperatures and shear stress. Despite the fact that degradation effects were visible in wood/PLA composite materials, such systems remained thermally more stable than pure polymers. [ABSTRACT FROM AUTHOR]