Cu-based metalorganic systems: an ab initio study of the electronic structure

Within a first principles framework, we study the electronic structure of the recently synthesized polymeric coordination compound Cu(II)-2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene (CuCCP), which has been suggested to be a good realization of a Heisenberg spin-1/2 chain with antiferromagnetic coupling. By using a combination of classical with ab initio quantum mechanical methods, we design on the computer reliable modified structures of CuCCP aimed at studying effects of Cu-Cu coupling strength variations on this spin-1/2 system. For this purpose, we performed two types of modifications on CuCCP. In one case, we replaced H in the linker by i) an electron donating group (NH2) and ii) an electron withdrawing group (CN), while the other modification consisted in adding H2O and NH3 molecules in the structure which change the local coordination of the Cu(II) ions. With the NMTO-downfolding method we provide a quantitative analysis of the modified electronic structure and the nature of the Cu-Cu interaction paths in these new structures and discuss its implications for the underlying microscopic model.Comment: 18 pages, 11 figures, final versio

Versatile electrochemiluminescent organic emitters

namely polycyclic aromatic hydrocarbons, have been the first molecules investigated since the beginning of ECL studies. Moving from organic solvents to water-based solutions in view of analytical applications, the attention on ECL emitters shifted to soluble inorganic complexes, which prevailed in both fundamental and applied research. However, the investigation of organic molecules has recently revived owing to new synthetic procedures and concepts. Polymeric nanoparticles, and thermally activated delayed fluorescence (TADF) sparked the research with renovated interest for organic molecules. Here, we introduce and summarise these new concepts behind organic emitters for ECL

Site Characterization Data Model and GIS-based Tools for Offshore Engineering Projects

Offshore engineering projects require the management of a huge amount of heterogeneous georeferenced data - among others metocean, geophysical, geotechnical, and environmental, which need a Data Model, data visualization and data analytics features on a common geographic basis. A Digital Data Platform (DDP) has been developed on a GIS ambient with the aim to speed up the engineering design process (i.e. minimization of routine operations), and also prevent misalignment of the data originating from different sources from Owner to Suppliers and any potential loss of information. The proposed GIS architecture is composed by two main components: i) the Data Model geodatabase, and ii) the GIS-Model Toolbar add-in. The proposed development represents a step forward on the definition of a common specification and dictionary for offshore project execution overcoming the current bottlenecking and inefficiency on the design phases between the project owner and the engineering contractor. The paper illustrates “what” and “how”, and in particular: i) the geodatabase and Data Model framework, ii) the required parameters to be organized and stored for offshore engineering design, and iii) the widgets implementation (i.e. GIS-based tools). Its application on a case study project with practical examples is presented.

Simplicial temporal networks from Wi-Fi data in a University Campus: the effects of restrictions on epidemic spreading

Wireless networks are commonly used in public spaces, universities and public institutions and provide accurate and easily accessible information to monitor the mobility and behavior of users. Following the application of containment measures during the recent pandemic, we analyse extensive data from the WiFi network in a University Campus in Italy during three periods, corresponding to partial lockdown, partial opening, and almost complete opening. We measure the probability distributions of groups and link activation at Wi-Fi Access Points, investigating how different areas are used in the presence of restrictions. We rank the hotspots and the area they cover according to their crowding and to the probability of link formation, which is the relevant variable in determining potential outbreaks. We consider a recently proposed epidemic model on simplicial temporal networks and we use the measured distributions to infer the change in the reproduction number in the three phases. Our data show that additional measures are necessary to limit the epidemic spreading in the total opening phase, due to the dramatic increase in the number of contacts

Numerical Analysis of Real Fluid Behavior Effects on a Sliding-Vane Compressor Comprehensive Model

This work presents a simulation model on a sliding vane compressor based on a lumped parameter model. The model is capable of predicting the performance of sliding-vane compressors. The model is divided into different sub-sections to evaluate the compressor's geometry, kinetics, thermodynamics, and rotor dynamics. The output of the tool includes the compressor unit's performance, such as volumetric flow rate, mechanical power, and process efficiency. The study examines the tool's ability to perform quick and efficient analyses using using either ideal or real fluid characterization, based on the REFPROP code. The code is validated against one experimental point. Simulations were conducted on a mid-size sliding-vane rotary compressor operating with three different types of working fluids from 20 °C and 1 bar (absolute) to 11 bar at 1500 rpm. In the ideal fluid case, simulations took 10–27 s, while real fluid assumptions took 1038–4329 s. The volumetric flow rate was influenced by the gas used, but changes among fluid models were not substantial, with a mean absolute percent difference of 0.5%. Mechanical power consumption was affected by the fluid choice and gas model, leading to a mechanical power difference between 0.4 and 1.1% in the ideal gas case. The specific mechanical work showed greater deviations among the fluids, with methane molar mass coherently increasing its value. Results show that the model developed is able to assess the major phenomena of sliding-vane compressors, and the ideal fluid model should be preferred when possible since computational times are significantly reduced with comparable results

Thermodynamic modeling of hydrogen refueling for heavy-duty fuel cell buses and comparison with aggregated real data

Abstract The foreseen uptake of hydrogen mobility is a fundamental step towards the decarbonization of the transport sector. Under such premises, both refueling infrastructure and vehicles should be deployed together with improved refueling protocols. Several studies focus on refueling the light-duty vehicles with 10 kgH2 up to 700 bar, however less known effort is reported for refueling heavy-duty vehicles with 30–40 kgH2 at 350 bar. The present study illustrates the application of a lumped model to a fuel cell bus tank-to-tank refueling event, tailored upon the real data acquired in the 3Emotion Project. The evolution of the main refueling quantities, such as pressure, temperature, and mass flow, are predicted dynamically throughout the refueling process, as a function of the operating parameters, within the safety limits imposed by SAE J2601/2 technical standard. The results show to refuel the vehicle tank from half to full capacity with an Average Pressure Ramp Rate (APRR) equal to 0.03 MPa/s are needed about 10 min. Furthermore, it is found that the effect of varying the initial vehicle tank pressure is more significant than changing the ambient temperature on the refueling performances. In conclusion, the analysis of the effect of different APRR, from 0.03 to 0.1 MPa/s, indicate that is possible to safely reduce the duration of half-to-full refueling by 62% increasing the APRR value from 0.03 to 0.08 MPa/s

Use of drawing in the biology classroom : the teachers’ perspective

Gjennom laboratoriekurs på Norges miljø- og biovitenskapelige universitet og bruk av tegning som studieteknikk, har vi selv opplevd de mange mulighetene tegning har å by på. Dette gjorde oss interesserte i å undersøke hvilke muligheter og utfordringer som finnes rundt bruk av tegning som læringsaktivitet i biologi på videregående trinn. Lærere har metodefrihet, noe som betyr at de selv står fritt til å velge de læringsaktivitetene de mener er hensiktsmessige for å oppnå læreplanmålene i faget. Å variere læringsaktiviteter er også med på å gjøre undervisningen variert og oppfylle kravet om tilpasset opplæring. Til grunn for denne masteroppgaven er forskningsspørsmålet: Hvilke muligheter og utfordringer finnes ved bruk av tegning som læringsaktivitet i biologi på videregående trinn? Til dette overordnede spørsmålet har vi formulert tre underspørsmål: (1) Hvordan bruker lærere tegning som læringsaktivitet i biologiundervisningen? (2) Hvilke muligheter opplever lærerne at tegning som læringsaktivitet gir? (3) Hvilke utfordringer erfarer lærerne i forbindelse med bruk av tegning i biologiundervisningen? Studien tok form som en multippel casestudie med lærere fra en steinerskole og fra en offentlig videregående skole. Først observerte vi en biologitime der tegning ble brukt som læringsaktivitet. Deretter utførte vi semistrukturerte enkeltintervjuer med lærerne fra begge skolene. Utvalget i studien er biologilærere med en fartstid i skolen fra fem til over 30 år med ulik erfaring med bruk av tegning. Tematisk analyse ble utført av det empiriske datamaterialet. Drøftingen viser at lærerne opplever flere muligheter enn utfordringer. Hovedfunnene fra vår studie er at lærere opplever at tegning gir muligheter opp mot vurdering, for å jobbe med det det tverrfaglige temaet bærekraftig utvikling og dybdelæring. Blant utfordringene er manglende tegneutstyr, tidsbruk og manglende kultur for bruk av tegning i biologi. Vi konkluderer med at det må rettes mer forskning mot effekten av etterutdanningstilbud for lærere i bruk av tegning. Da det finnes etterutdanningskurs og ressurser for hvordan tegning kan brukes i biologi, argumenterer vi for at det bør rettes mer forskning mot effekten av disse tilbudene opp mot våre funn.Through laboratory courses at the Norwegian University of Life Sciences and personal experience with drawing as a study technique, we have experienced the many learning possibilities that drawing has to offer. This made us interested in investigating the opportunities and challenges that drawing can offer as a teaching activity. In the Norwegian school system, teachers are free to choose the learning activities they believe are appropriate to achieve the curricular goals. Teachers are, however, encouraged to vary the teaching and learning activities to avoid monotony and to accommodate different students and their different learning requirements. In our experience, drawing as a student activity is seldom utilized by biology teachers. Our master’s project is based on the following question: What opportunities and challenges exist when using drawing as a learning activity in biology at the upper secondary level? We then formulated three sub-questions: (1) How do teachers use drawing as a learning activity in biology lessons? (2) What opportunities do teachers experience that drawing as a learning activity provides? (3) What challenges do teachers experience in connection with the use of drawing as a learning activity? The inquiry took the form of a multiple case study with educators from a Waldorf school and a public school teaching at the upper secondary level. The sample in the study consists of biology teachers with a teaching career reaching from five to over 30 years. We observed a biology class where drawing was used as a learning activity. Then we conducted individual, semistructured interviews with the teachers. Thematic analysis was performed on the empirical data material. The analysis of the empirical data shows that as a group, teachers experienced more opportunities than challenges. As possibilities, our main findings include that drawing is fit to use as part of the assessment, to work with the cross-curricular goal of sustainable development, and in-depth learning. As challenges, our findings include a lack of time and lack of drawing equipment, as well as lacking school culture for utilizing drawing as a learning activity in biology. We found several resources and courses for teachers to learn more about how to use drawing as a learning tool and we suggest more research regarding the effects of these courses compared to our findings.M-LU

Interleukin‑6 signalling as a valuable cornerstone for molecular medicine (Review)

The biological abilities of interleukin‐6 (IL‐6) have been under investigation for nearly 40 years. IL‐6 works through an interaction with the complex peptide IL‐6 receptor (IL‐6R). IL‐6 is built with four α‐chain nanostructures, while two different chains, IL‐6Rα (gp80) and gp130/IL6β (gp130), are included in IL‐6R. The three‐dimensional shapes of the six chains composing the IL‐6/IL‐6R complex are the basis for the nanomolecular roles of IL‐6 signalling. Genes, pseu‐ dogenes and competitive endogenous RNAs of IL‐6 have been identified. In the present review, the roles played by miRNA in the post‐transcriptional regulation of IL‐6 expression are evaluated. mRNAs are absorbed via the ‘sponge’ effect to dynamically balance mRNA levels and this has been assessed with regard to IL‐6 transcription efficiency. According to current knowledge on molecular and nanomolecular structures involved in active IL‐6 signalling, two different IL‐6 models have been proposed. IL‐6 mainly has functions in inflamma‐ tory processes, as well as in cognitive activities. Furthermore, the abnormal production of IL‐6 has been found in patients with severe acute respiratory syndrome coronavirus 2 (SARS‐coV‐2; also known as cOVId‐19). In the present review, both inflammatory and cognitive IL‐6 models were analysed by evaluating the cytological and histological loca‐ tions of IL‐6 signalling. The goal of this review was to illustrate the roles of the classic and trans‐signalling IL‐6 pathways in endocrine glands such as the thyroid and in the central nervous system. Specifically, autoimmune thyroid diseases, disorders of cognitive processes and SARS‐coV‐2 virus infection have been examined to determine the contribution of IL‐6 to these disease states