Validation of the transient liquid crystal thermography technique for heat transfer measurements on a rotating cooling passage

The transient liquid crystal thermography can be a suitable tool to study heat\u2010transfer performances on internal cooling schemes of gas turbine blades. One of the hot topics related to this methodology is about the level of reliability of the heat\u2010transfer assessments in rotating tests where the fluid experiences time\u2010dependent rotating effects. The present study contribution aims to experimentally validate by cross\u2010comparison of the outcomes obtained by employing the transient technique with those from the steady\u2010state liquid crystal thermography in which the rotational effects occur as time\u2010stable by definition. Heat\u2010transfer measurements have been conducted on a rib\u2010roughened square cross\u2010section channel, with an inlet Reynolds number equal to 20,000 and rotation number up to 0.2. Special attention has been paid to the definition of the more reliable calibration strategy for liquid crystals that are employed in the transient thermography and to the proper estimation of the heat losses in the post\u2010processing of the steady\u2010state experimental data. The results show great accordance between the indications provided by the two techniques both in static and rotating conditions, demonstrating the possibility to exploit the advantages of the transient liquid crystal thermography for the investigation of heat transfer into rotating cooling channels

Mudbricks, Construction Methods, and Stratigraphic Analysis : A Case Study at Tell Timai (ancient Thmuis) in the Egyptian Delta

The Graeco-Roman site of Tell Timai (ancient Thmuis) in Lower Egypt is among the largest urban tells in the Nile Delta, boasting substantial amounts of preserved earthen architecture. Although earthen architecture made up the vast majority of public and domestic structures in ancient Egypt, it still does not receive the same analytical attention from archaeologists as other categories of evidence. This paper presents a case study for the archaeological investigation of the earthen architecture at Tell Timai. The goal was to develop a methodology that can be implemented in the field by excavators with little geoarchaeological training and limited laboratory access in order to generate useful data for determining building stratigraphy and studying construction processes. Through the close examination and sampling of three buildings of different periods and scales, we tested a new field methodology combining geoarchaeological techniques and mensiochronology. The results provide information useful for stratigraphy and phasing as well as for identifying specific patterns of mudbrick manufacturing, production, and construction during the Graeco-Roman period at Tell Timai.Peer reviewe

Tweeting the meeting. Quantitative and qualitative twitter activity during the 38th ESSO conference

Introduction: Social media is increasingly used to share information with the potential for fast and wide reach. Data on use during surgical oncology conferences is limited. We aimed to monitor twitter usage during a surgical oncology conference to audit impact of activity. Methods: A prospective, time-restricted, observational study of twitter activity using the #ESSO38 hashtag in the week before and during the 38th ESSO conference (10–12 October 2018; Budapest, Hungary). Data on individual tweets and retweets, including date and tweeter or retweeter were collected using NodeXL, FollowTheHashtag, Twitonomy and TAGS. Results: The study period (10–13 October) documented 328 tweets by 58 tweeters with 1167 retweets, with a soaring activity and mentions during the conference days, with a potential reach at over 7.5 million. The nodal network of tweets, the most active tweeters and retweeters are presented as well as the most frequently used hashtags. The top 3 hashtags used were #ESSO38, #SoMe4Surgery# and #EYSAC. A positive influence on the @ESSOweb twitter handle was noted, with the numbers of followers growing from 1.5 K to over 1.8 K representing a 20% growth in just over a week. Conclusions: Activity on tweeter during the conference was considerable, with a potential for a wide reach beyond those attending the conference. A more structured approach to the use of twitter for future conferences may enhance experience, activity and reach

Myoblast adhesion, proliferation and differentiation on Human Elastin-Like Polypeptide (HELP) hydrogels

Purpose: The biochemical, mechanical and topographic properties of extracellular matrix are crucially involved in determining skeletal muscle cells morphogenesis, proliferation and differentiation. Human elastin-like polypeptides (HELPs) are recombinant biomimetic proteins designed to mimicking some properties of the native matrix protein; when employed as myoblasts adhesion substrates they stimulate in vitro myogenesis. Given the consequences that biophysical properties of extracellular matrix exert on skeletal muscle cells, the aim of this work was to investigate the effects of HELP hydrogels on myoblasts viability and functions. Methods: We recently synthesized a novel polypeptide, HELPc, by fusing the elastin-like backbone to a 41aa stretch present in the α2 chain of type IV collagen, containing two RGD motifs. To obtain hydrogels, the enzymatic cross-linking of the HELPc was accomplished by transglutaminase. Here, we employed both non cross-linked HELPc glass coatings and cross-linked HELPc hydrogels at different monomer density as adhesion substrates for C2C12 cells, used as myoblasts model. Results: By comparing cell adhesion, proliferation and differentiation, we revealed several striking differences. Depending on support rigidity, adhesion to HELPc substrates dictates cell morphology, spreading, focal adhesions formation and cytoskeletal organization. Hydrogels greatly stimulated cell proliferation, particularly in low serum-medium, and partially inhibited myogenic differentiation. Conclusions: In the whole, the results underline the potentiality of these genetically engineered polypeptides as a tool for dissecting crucial steps in myogenesis

Improving IBD diagnosis and monitoring by understanding preanalytical, analytical and biological fecal calprotectin variability

BACKGROUND: The appropriate clinical use of fecal calprotectin (fCal) might be compromised by incomplete harmonization between assays and within- and between-subjects variability. Our aim was to investigate the analytical and biological variability of fCal in order to provide tools for interpreting fCal in the clinical setting. METHODS: Experiments were conducted to investigate the effects of temperature and storage time on fCal. Thirty-nine controls were enrolled to verify biological variability, and a case-control study was conducted on 134 controls and 110 IBD patients to compare the clinical effectiveness of three different fCal assays: ELISA, CLIA and turbidimetry. RESULTS: A 12% decline in fCal levels was observed within 24 h following stool collection irrespective of storage temperature. Samples were unstable following a longer storage time interval at room temperature. Within- and between-subjects fCal biological variability, at 31% and 72% respectively, resulted in a reference change value (RCV) in the region of 100%. fCal sensitivity in distinguishing between controls and IBD patients is satisfactory (68%), and the specificity high (93%) among young (<65 years), but not among older ( 6565 years) subjects (ROC area: 0.584; 95% CI: 0.399-0.769). Among the young, assays have different optimal thresholds (120 \u3bcg/g for ELISA, 50 \u3bcg/g for CLIA and 100 \u3bcg/g for turbidimetry). CONCLUSIONS: We recommend a standardized preanalytical protocol for fCal, avoiding storage at room temperature for more than 24 h. Different cutoffs are recommended for different fCal assays. In monitoring, the difference between two consecutive measurements appears clinically significant when higher than 100%, the fCal biological variability-derived RCV

Fabrication of Nanostructured GaAs/AlGaAs Waveguide for Low-Density Polariton Condensation from a Bound State in the Continuum

Exciton-polaritons are hybrid light-matter states that arise from strong coupling between an exciton resonance and a photonic cavity mode. As bosonic excitations, they can undergo a phase transition to a condensed state that can emit coherent light without a population inversion. This aspect makes them good candidates for thresholdless lasers, yet short exciton-polariton lifetime has made it difficult to achieve condensation at very low power densities. In this sense, long-lived symmetry-protected states are excellent candidates to overcome the limitations that arise from the finite mirror reflectivity of monolithic microcavities. In this work we use a photonic symmetry protected bound state in the continuum coupled to an excitonic resonance to achieve state-of-the-art polariton condensation threshold in GaAs/AlGaAs waveguide. Most important, we show the influence of fabrication control and how surface passivation via atomic layer deposition provides a way to reduce exciton quenching at the grating sidewalls