bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary results from GPR survey at the Roman villa of Caddeddi (Siracusa, Italy)
Authors: Tanasi D. , Hassam S. , Trapani P. , Cali D. , De Giorgi L. , Ferrari I. , Giuri G. , Leucci G.
Published: April 2022

The Villa of Caddeddi, in the territory of Noto (Siracusa) is located on the south bank of the Tellaro river, about 3km from its mouth. The site, interpreted as a rural luxury residence dated to the 4th-5th century CE, was first discovered in 1972 and intermittently investigated in the subsequent decades and mostly studied from the perspectives of the splendid mosaic floors there uncovered. The excavated structure accounts for just a portion of the complex, which is partially covered by an 18th-19th century farmhouse. After a long period of neglect, the villa has been recently restored and opened to the public and become subject of new studies by the University of South Florida’s Institute for Digital Exploration (IDEx) which in 2019 and 2020 conducted a remote sensing campaign entailing terrestrial laserscanning and ground penetrating radar.
Integrated Archaeological and Geophysical Surveys in the Historical Center of Augusta (Eastern Sicily, Italy).
Authors: Cacciaguerra G. , De Giorgi L. , Fragalá G. , Leucci G.
Published: April 2022

Augusta was founded by Emperor Frederick II between 1233/34 and 1238/39 on a peninsula. Despite its short history, over the centuries the town has undergone profound transformations due to demolitions (1680-1682) and earthquakes (1542, 1693) that have changed its architectural and urban features. Integrated archaeological and geophysical investigations were undertaken to solve specific archaeological problems which are part of a wider debate regarding the phenomena connected to the medieval and urban layout and archaeological potential analysis. Particularly the geophysical surveys undertaken in the historical center of Augusta, by means Ground-penetrating Radar (GPR), allowed a 3D reconstruction of archaeological structures in the subsoil until the depth of about 4m.
Digital survey and reconstruction for enhancing epigraphic readings with erode surface
Authors: Limongello M , Antinozzi S , Vecchio L , Fiorillo F
Published: April 2022

The contribution illustrates the applied procedure of the digital survey and documentation of a funerary epigraph written in Greek but dating back to the Roman period (dimensions of about 31 cm x 20 cm). It comes from Velia (Salerno), a Greek and then Roman city in southern Italy. It was found in 1967 and currently represents the only Greek funerary inscription of the Roman period coming, most probably, from the necropolis of Porta Marina Sud. The inscription presents many gaps and preserves only part of the upper right and lower margins. The surface is highly eroded, maybe due to the exposure to atmospheric agents, making the text interpretation extremely difficult. The implemented image-based and range-based techniques contributed to reading the inscriptions, letting to recover much information that was invisible to the naked eye. The 3D survey system choice has to be consistent with the work aims and the physical object characteristics. A high degree of geometric detail was essential for our case study. Therefore, a triangulation laser scanner performed the first digital capturing, subsequently integrated with a structured light system (Artec Eva and Leo) and finally, a close-range photogrammetric acquisition to produce a high-resolution orthophoto.
Rehydroxylation: a promising technique for ceramic dating
Authors: Maspero F , Galli A , Panzeri L , Martini M
Published: April 2022

The kinetics of expansion in ceramic materials due to rehydration and rehydroxylation was investigated since the early XX century as a cause of crazing in glazed ceramics. Since then, the study of expansion and mass gain of ceramic has been studied extending the monitored times and modeling the involved processes. In the last 20 years, the interest in this process grew due to its possible application in the dating field, supporting well-established techniques such as thermoluminescence and optically stimulated luminescence. The principle of the dating technique is based on the fact that after the firing all water and hydroxyl molecules are desorbed from the ceramic structure, and after cooling are slowly adsorbed following a mathematical law. Nowadays, the correlation between time and mass gain is well established, but there is still no agreement on the mathematical model of the rehydroxylation process, and on a reliable protocol to date the materials. However, promising results have been reached, and more efforts must be put into the study of the role of involved parameters (storage temperature, activation energy, experimental setup…). Considerations on the last point will be shown, together with experimental evidence collected at Lambda (Laboratory of Milano Bicocca university for Dating and Archaeometry).
Traffic-induced vibrations on cultural heritage in urban area: the case of Villa Farnesina in Rome
Authors: Costanzo Antonio , Falcone Sergio , Piana Carmelo La , Lapenta Virginia , Musacchio Massimo , Sgamellotti Antonio , Buongiorno Maria Fabrizia
Published: April 2022

The study aims to analyse the vibrations induced by traffic on the Villa Farnesina in Rome. The ancient building was designed and erected by the architect Baldassarre Peruzzi and the walls, vaults and lodges were decorated with frescoes attributable to Raphael and other relevant Italian Renaissance painters. Villa Farnesina is located near the Lungotevere road, therefore it suffers the dangerous effects due to the urban traffic even with heavy vehicles passing, so much so that in the early seventies an anti-vibration paving was built. A six-month geophysical monitoring made it possible to analyse the propagation of the waves on the building, characterizing the vibration due to the current traffic level. The results show the vibration levels recorded on the different floors of the building.
Soft Ionization mass spectrometry of lipid residues in archaeological findings: ESI vs APCI
Authors: Saliu Francesco
Published: April 2022

The organic residues that are found preserved in ceramics may be an extraordinary source of information regarding the function of the archaeological items and therefore provide insights on the life of our ancestors. In this view, lipids, that make up a major part of naturally occurring fats and oils, have gained in the last decades a special attention in molecular archaeology research. However, speciation of lipid is rather complicated due to the variety of congeners, the existence of several structures within the same raw formula, the presence of positional isomers. Soft ionization coupled to mass spectrometry has been proved to be powerful tool to manage this complexity because enable structural elucidation trough a tailored fragmentation, and may adopted with low amount of sample even as mixture, which is not suitable to other analytical techniques. Under this respect, mass spectra obtained from artificial weathered reference material and archaeological material are here presented, and some interesting feature discussed, with a specific focus to triacylglycerols (TAGs) the most abundant lipid class in fat and oils
The activities of the LAMBDA (Laboratory of Milano Bicocca university for Dating and Archaeometry): what’s new?
Authors: Panzeri L , Galli A. , Maspero F , Saleh M , Martini M
Published: April 2022

The LAMBDA, Laboratory of Milano Bicocca University for Dating and Archaeometry, has a forty-years experience started with the first thermoluminescence dating activities in Italy in the early eighties. Soon after, other dating techniques (Optically Stimulated Luminescence, OSL, Radiocarbon, Dendrochronology and recently Rehydroxylation) have been studied and dedicated laboratories have been set up, where the physical basis of the techniques are constantly under investigation, mainly for what concerns the role of defects in quartz in the luminescence processes. LAMBDA covers other prominent archaeometry fields such as dating of mortars by OSL and Radiocarbon, surface dating of bricks and rehydroxylation dating. In this paper we will present the recent results in dating field focusing on mortar and surface dating. Furthermore, the results of a recent dating campaign to rediscover ancient Milan will be presented.
Development of a novel probe for measuring emissivity and temperature during Raman spectroscopy
Authors: Calvagna C , Mencaglia A A , Osticioli I , Ciofini D , Siano S
Published: April 2022

In this work, an innovative tool to perform real-time measurements of emissivity and temperature of a given material surface under CW laser irradiation was developed. In the radiative energy balance, the emissivity represents the complementary component of the reflectance, thus, its measurement can be exploited to calculate the temperature at the target surface from infrared emission measurements provided by a suitable sensor. A miniaturized photothermal sensing line was designed as an accessory of Raman probes for driving thermal control loops in order to prevent overheating during the spectroscopic acquisition. To demonstrate its effectiveness and reliability, it was integrated with in a home-made Raman instrument (exc. 1064 nm) and associated software to achieve an automated online thermal control. Temperature rise during Raman spectroscopy can induce chemical alterations of the material under analysis and seriously affect its original spectral features. In several applications, such photothermal side effects can represent a serious problem to be carefully controlled in order to safeguard the integrity of the material and its spectral fingerprint. A thorough experimentation of the novel tool was carried out on photothermally sensitive materials such as red lead and massicot powders, traditionally used as pigments since ancient times. Finally, the compactness of the components and the fast response time made this system particularly suitable for nondestructive in-situ investigations.
Quantitative evaluation of the Reflectance Transformation Imaging and Normal Integration technique in profilometric application.
Authors: Verni E. , Fiocco G. , Grifoni E. , Lippolis G. , Ludwig N. , Malagodi M. , Pisani M. , Rovetta T. , Zucco M. , Gargano M.
Published: April 2022

This article provides a quantitative analysis of the ability to faithfully reproduce the profile of objects using the Reflectance Transformation Imaging (RTI) coupled with Normal Integration technique. The study was conducted using ad hoc designed and built reference targets. It was possible to compare the profiles obtained using RTI technique with those realized using more conventional profilometric and 3D techniques such as micro photogrammetry, laser scanner and optical profilometry. It has been seen that the RTI technique is especially valid in the reproduction of high spatial frequencies and that it is very suitable for the study of cultural heritage, as it is portable, fast and low-cost.
Seismic behaviour and 3D reconstruction of Cultural Heritage: the Column of the Hera Lacinia Temple in Capo Colonna (Calabria, Southern Italy)
Authors: Costanzo Antonio , Cosentino Antonio Giulio , Gaudio Pierdomenico del , Aversa Gregorio , Pascuzzi Francesco
Published: April 2022

The study aims to characterize the seismic behaviour of the Doric Column, last remaining of the Hera Lacinia Temple, located on the promontory of Capo Colonna near Crotone (Calabria, Southern Italy). Recordings of ambient vibration has been acquired both at the base and on the top of the column, simultaneously, in order to detect the predominant frequencies of the element. In addition, a high-resolution 3D model of the column has been reconstructed through laser scanning to support the analysis of the current state of the heritage element. The fundamental frequencies of the column and those associated to the site have been compared to verify potential resonance phenomena at the occurrence of an earthquake. In addition, a significant inclination of the column was detected by analysing the 3D model.
Terrestrial laser scanning for the modelling of indoor archaeological areas: two case-studies from Reggio Calabria, Italy
Authors: Giuffrida Dario , Nardo Viviana Mollica , Neri Daniela , Cucinotta Giovanni , Calabrò Irene Vittoria , Pace Loredana , Ponterio Rosina Celeste
Published: April 2022

The work shows the application of a portable terrestrial laser scanner for the three-dimensional survey and modelling of two archaeological areas preserved in the urban fabric of Reggio Calabria, Italy: the underground site of Piazza Italia, better known as “Ipogeo”, and the ruins of the s.c. odéon, located in the basement of a residential building in via 24 Maggio. The two case studies, compared to the other sites preserved in the city center, share a common element: they are not outdoors but have been incorporated into modern buildings and therefore they are not immediately visible. Due to the specific features of the sites, the use of a portable laser-scanning system has been considered the most suitable, accurate and quick solution in order to produce high-resolution as-built 3d models of the structures. The latter will be used as support to derive plans and sections, to carry out further virtual reconstructions and to plan a scan-to-bim process.
Challenges in laser cleaning of cultural heritage stained glass
Authors: Maingi Evan Maina , Treil Valérie , Abad María Pilar Alonso , Angurel Luis A , Rahman Md Ashiqur , Chapoulie Remy , Dubernet Stephan , Schiavon Nick , Fuente German F de la
Published: April 2022

Stained-glass windows play an important role in cultural heritage. Human and environmental factors have subjected these pieces to risks of damage. Mechanical and chemical-based cleaning methods have been used for their restoration and conservation. Additionally, short-pulse lasers have opened new opportunities for safe and controlled cleaning and restoration of these important materials. In this work, ultra-short pulsed lasers were used to clean an artificially applied coating from the surface of a contemporary colorless glass frequently used in the restoration of stained-glass windows. One of the objectives was to explore the applicability of using these types of lasers to safely clean historical stained-glass windows. It was observed that temperature rise and subsequent heat accumulation in the coating layer being removed was sufficient to generate significant thermal stresses on the underlying glass surface leading to damages even when the laser energies are lower than the damage thresholds. Some laser treatments that limit this heat accumulation were designed in this study. For laser systems operating at frequencies in the range of several hundreds of kHz, the option was to work in burst mode, limiting the number of pulses in each burst and selecting an adequate time lapse between two consecutive burst runs. A method to uniformly clean a given surface is proposed in this work. When lower frequencies are available, treatments using frequencies lower than 20 kHz are enough to safely clean the glass. When UV laser radiation is used, optical damage is also an important aspect to be considered. In this case, the cleaning protocol has to deal with both issues, to avoid heat accumulation and chemical damage.
A method to improve the accuracy of sparse UAV point cloud applied to the Amphitheater of Pompeii
Authors: Barba S , Di Benedetto A , Fiani M , Gujski LM
Published: April 2022

In the field of cultural heritage dissemination, the availability of an accurate 3D model is mandatory to better describe an historically relevant building and provide the user with as much information as possible. In our paper we propose a workflow to improve the accuracy of the sparse cloud (Tie Points) by means of automated mask generation on photograms acquired by UAV (Unmanned Aerial Vehicle). In the first step, the statistical distribution of reprojection errors for each image, before applying the masks, is analyzed. In the second step, masks are automatically generated for each image to exclude, in the following alignment process, parts of the image characterized by reprojection error values outside the chosen confidence interval. The BIC criterion was used to identify the probability distribution that best fits the data. The results are promising and highlight the need to implement specific processes for preparing the input data to improve the accuracy of the output 3D model. Such results are not easily achievable with the processes implemented by default in the most widely used commercial photogrammetric software.
The combination of RPLC-ESI-FTMS/MS and m-CPBA epoxidation for the location and geometry assignment of double bonds in unsaturated fatty acyl chains of drying oils
Authors: Coniglio D , Calvano C D , Masiello M , Losito I , Sabbatini L , Cataldi T R I
Published: April 2022

Oil painting is the process of painting with drying oils as binders. Such oils mainly consist of triacylglycerols characterized by high levels of unsaturated fatty acyl chains. For instance, poppy seed oils have received much attention for their use as oil paints since very ancient time. Upon exposure to oxygen, not only do drying oils harden to a densely cross-linked polymer network through radical reactions, but their fatty acids also interact with cations of some pigments forming the related carboxylate salts. These so-called metal soaps lead to severe degradation phenomena because they can migrate and aggregate, breaking through the surface of the paint. Since the fatty-acidome of a drying oil is involved in these processes, the current study is chiefly devoted to the identification of both free and total fatty acids in poppy seed oil by reversed-phase liquid chromatography coupled with high-resolution mass spectrometry by an electrospray ionization source (RPLC-ESI-FTMS). Total fatty acids (TFA) were investigated by enzymatic hydrolysis and comparisons were made between the free fatty acid (FFA) profile and the total one resulting from the digestion on the same poppy seed oil. A key component of our approach was the double bond (C=C) epoxidation reaction, which was carried out on unsaturated fatty acids by meta-chloroperoxybenzoic acid (m-CPBA). A chromatographic set up was developed to separate such oxidized lipids, that were identified as deprotonated molecules [epoM-H]− by accurate mass matching in full mass spectra. Their epoxide ring was subsequently cleaved upon tandem mass fragmentation to yield a pair of diagnostic product ions for C=C double bond localization. Interestingly, the double bond geometry (i.e., cis/trans) was also assigned based on the retention times of derivatized-FA. The present approach opens new avenues for the analysis of artworks whether affected by metal soap-related degradation phenomena.
Technical observations about a possible new portion of the Aqua Iulia Roman aqueduct in the municipality of Ciampino (Italy).
Authors: Blanco D , Alessandri L , Alimonti C , Baiocchi V , Sebastiani Del Grande P , Serio G
Published: April 2022

An intersection of two roman glareatae roads and an underground stretch of a Roman aqueduct (rivus subterraneus) were found in the locality of Colle Oliva, during an emergency archaeological investigation (between 11/2018 and 3/2019). The aqueduct has been detected in several test trenches and some profiles have been obtained. These data shade some light about the Roman hydraulic technology and they show how the land morphology affected the shape and the path of the aqueduct.
Integrated Survey and 3D Processing on Enea CRESCO Platform: the Case Study of San Nicola in Carcere in Rome
Authors: Puccini Marco , Camassa Antonio , Mongelli Maria Luisa , Pierattini Samuele , Migliori Silvio , Canciani Marco , Spadafora Giovanna , Saccone Mauro
Published: April 2022

This paper shows the experimental activities carried out by a joint research group on the case study of the Basilica di San Nicola in Carcere in Rome, concerning the integration of different 3D reconstruction technologies in the Cultural Heritage domain. Dataset obtained from laser scanner and photogrammetry, were processed on a remote platform based on the powerful ENEA computational infrastructure, in order to analyse the dense clouds, to compare them and to improve the quality of the data. This paper also shows the efforts to upgrade this platform and the optimisation of the processes.
Analysis of twelve wooden spear throwers covered with gilded copper from the Moche tomb of the Lady of Cao
Authors: Cesareo Roberto , Angel Bustamante D , Régulo Franco J , Arabel Fernández L
Published: April 2022

Twelve spear throwers from the tomb of the “Lady of Cao” were analyzed with a portable equipment which uses energy-dispersive X-ray fluorescence (EDXRF). The pre-Columbian tomb of the Lady of Cao is located about 50 km north of Trujillo, in the north of Peru, and is dated around 350 A.D. The spear throwers are on gilded copper over a wood cylindrical structure. All analyzed spears have a similar gilding, and four of them have also additional much smaller gilding rings covering the wood structure. These rings are clearer and contain more silver, in three cases about the double, in one case about five times the silver of “normal” gilding. There were two problems to solve: the first one is related to the composition of the gildings, the second one is related to the determination of their thickness. The last problem, which is much critical, was solved using a new method based on the different attenuation of fluorescent X-rays by the gildings.
Analysis of the famous Moche head “Cabeza de Mono Dorada”
Authors: Cesareo Roberto , Angel Bustamante D.
Published: April 2022

On December 8, 2011, a famous Moche monkey head on gold was returned from USA to the government of Peru, because illegally exported many years before. Since 2012 the monkey head was kept at the Ministry of Culture, which is located in the same building as the National Museum in Lima, waiting for final destination. The small monkey head size is approximately 4.5 cm high and 7 cm diameter. It weighs 49 g. On February 2018 the artefact was non-destructively analyzed using a portable device for energy-dispersive X-ray fluorescence. The analyses showed that the monkey head is homogeneous, with following mean composition: Au = (77.5 ±2)%, Ag= (19 ±1.5)%, Cu = (3.5 ±1)%. This composition is consistent with the hypothesis that the artefact is of Moche origin.
Quantitative GIS-based analysis of archaeological data of the archaic state of Tell Mardikh/Ebla (3rd millennium BC): the Big-DEA project.
Authors: Peyronel Luca , Mandanici Emanuele , Mantellini Simone , Vacca Agnese , Bitelli Gabriele
Published: April 2022

The paper provides an overview on Big-DEA, a multidisciplinary project aimed at developing a comprehensive multi-level explanatory model for the development of an archaic State in the ancient Near East, using the exceptional case of Tell Mardikh, ancient Ebla (Syria), during the second half of the 3rd millennium. The project’s goal is the reconstruction of the archaic state organization through an integrated analysis of archaeological and epigraphic data. The interaction between humanities and hard sciences is adopted in order to build a multi-tier explanatory model regarding the territory under the control of the Ebla kingdom, considering anthropic and environmental data deriving from excavations, survey and textual sources. The way to managing and study such a large Big Data archive, which includes different datasets, is itself the main challenge of the project: the creation of a dedicated relational database management system (RDBMS) functional to the implementation of the available GIS platform and the development of an appropriate simulation framework.
Green synthesis of silver nanoparticles doped activated carbon for Rhodamine B dye adsorption
Authors: Mohd Mokhtar M A , Ali R R , Mohamed Isa E D , Tarmizi Z I , Zhe J C , Kasmani R M , Mohd Yunos D D
Published: April 2022

Application of dye is one of the major industry with various application from everyday attire to food colouring. However, dye pollution is serious and threatening issue that need to be address to avoid harmful effect towards humans, animals and environments. In this study, silver nanoparticles (Ag NPs) were synthesised via Clitoria Ternatea (CT) flower extract and doped with activated carbon (Ag NPs/AC) to act as adsorbent in removing rhodamine B dye (RB). CT Flower mediated green synthesis for Ag NPs provide safe, low cost and sustainable method compared to conventional chemical and physical synthesis. UV-visible spectroscopy was used to analyse the green synthesis for the formation of Ag NPs with peak absorbance at 400 nm. The effect of activated carbon (AC) mass loading, contact time and adsorbent dosage were analysed to study the adsorption capacity of Ag NPs/AC with viable condition of 0.75 g AC mass and 30 mg dosage with complete removal at 90 minutes. Hence, incorporation of Ag NPs with AC contributes to better adsorption properties for the removal of RB dye.
Optimization of Algae Residues Gasification: Experimental and Theoretical Approaches
Authors: Atikah M.S.N. , Taufiq Yap Y.H. , Ilyas R.A. , Harun Razif
Published: April 2022

Gasification is one of the thermochemical pathways of biomass conversion that produces synthesis gas, tar, and char. This study aims to convert algal residues via gasification at different operating conditions; temperature, equivalence ratio, and biomass loading. The study was carried out in 3 steps; (1) testing the outcomes of temperature and loading effects on synthesis gas yield, (2) experimental optimization of gasification via Design Expert, and (3) theoretical optimization of gasification via Aspen Plus simulation. Temperature and equivalence ratio highly influenced synthesis gas composition, while loading demonstrated less effect on the synthesis gas composition. The experimental and simulated gasification outcomes were compared to obtain optimized conditions that produce high H2 and CO yields. The data were validated using root mean square error. The optimized temperature, loading, and equivalence ratio were found for both algal residues that produced 36.38 and 13.28mol% of H2 and CO, respectively for lipid extracted algae (LEA) and 47.99 and 26.05mol% of H2 and CO, respectively for fucoidan extracted seaweeds (FEA). There was a considerable variation between experimental and simulated data due to the simulation and experimental limitations. The average Carbon Conversion Efficiency values were 66.36 and 80.42% for LEA and FES, respectively, denoting that LEA produced less carbon-containing products, while FES produced more carbon-containing products. In conclusion, LEA gasification yielded more H2 while FEA produced more CO.
Application of regenerated spent bleaching earth as an adsorbent for the carbon dioxide adsorption by gravimetric sorption system
Authors: Phey Melissa Low Phey , Abdullah Tuan Amran Tuan , Ahmad Arshad , Ali Umi Fazara Md
Published: April 2022

The atmospheric level of carbon dioxide (CO2) is indicated to be alarming which in turn has contributed to the worldwide environmental issue such as global warming. The goal of this project was to study the adsorption of CO2 onto regenerated spent bleaching earth (RSBE). Spent bleaching earth (SBE) can be a good adsorbent but it has the weakness in surface area due to the organic impurities left in the pores after being generated from the edible oil processing. Thus, the regeneration processes of SBE by (a) direct heat treatment, and (b) heat treatment followed by nitric acid treatment were studied to enhance the surface area, thus increasing the CO2 adsorption capacity. The SBE were calcined at four temperatures of 400, 500, 650 and 800 °C in the regeneration process. The surface properties of RSBE were characterized using Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) analysis and Brunauer–Emmett–Teller (BET) surface area analysis. The CO2 adsorption capacity on RSBE produced by heat treatment followed by nitric acid treatment was shown to be more effective than RSBE produced by direct heat treatment. RSBE_500_HNO3 offered highest surface area (192.81 m2/g) and give highest CO2 adsorption capacity of 86.67 mg CO2/g. In comparison to the low pressure condition, the high pressure CO2 adsorption values recorded for both RSBE were significantly better.
Effect of amine head group imparted to poly (glycidyl methacrylate) grafted fibrous adsorbent for CO2 adsorption
Authors: Mohamad Noor Ashikin , Nasef Mohamed Mahmoud
Published: April 2022

The demand to develop adsorbents for CO2 capture with high performance continued to grow extensively. Adsorbents with covalently bonded amine groups based on fibrous substrate modified by radiation-induced grafting copolymerization (RIGC) of glycidyl methacrylate (GMA) and amination treatment have emerged recently. In this study, GMA was grafted onto a polyethylene/polypropylene (PE/PP) fibrous sheet and the grafted intermediate was used to incorporate two different amine-containing agents, namely polyethyleneimine (PEI) and ethylenediamine (EDA) for CO2 adsorption. The chemical structural and morphological changes in the two aminated adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. A low and equal amination level of 20% was achieved in PEI-containing and EDA-containing adsorbents. The CO2 adsorption from a binary mixture of CO2/N2 (40:60 v/v) was not satisfactory despite a 30% higher adsorption capacity (50.44 mg/g) demonstrated by EDA-containing adsorbent compared to 34.51 mg/g for PEI-containing counterpart at 30 bar and at room temperature. More work is needed to elevate the CO2 adsorption capacity levels in such adsorbents by increasing the amination level via optimization of reaction parameters.
Production and characterization of biodiesel from canola oil through enzymatic transesterification
Authors: Shamsudin M.I. , Tan L S , Tsuji T , Kiew P L
Published: April 2022

Biodiesel, a promising type of biofuel, can be produced from various types of renewable feedstocks, ranging from animal fats to plant oil. It is mainly made up of fatty acid alkyl ester compounds due to the transesterification reaction. This work aims to synthesize and characterize biodiesel, known as fatty acid methyl esters, from canola oil using an enzymatic reaction involving immobilized Novozym 435 and Rhizomucor miehei (RM IM) lipase enzymes.4 g of canola oil was added to the reaction mixture consisting of 0.2 g immobilized lipase and 3:1 methanol to oil ratio. First, the enzymatic methanolysis reaction was conducted at the temperature of 35°C and at agitation rate of 216 rpm for 24 hours. Next, the synthesized biodiesel was characterized using the Gas Chromatography-Mass Spectroscopy (GC/MS) analysis. Based on the analysis results, the main fatty acid methyl esters present in both products were hexadecanoic acid, 9-octadecenoic acid (z)-, 9,12,15-octadecatrienoic acid, (z, z, z)-, and 11,14-eicosadienoic acid. The transesterification of canola oil using both enzymes consistently revealed methyl oleate as the methyl ester with the highest composition, ranging from 67 to 71 %. In conclusion, canola oil was successfully converted into fatty acid methyl ester via the enzymatic transesterification process in this study.
Enhancement of carbon dioxide adsorption performances by hydrazinolysis of poly(n-vinylformamide) grafted fibrous adsorbent
Authors: Zubair N A , Nasef M M , Abdullah E C , Ahmad A
Published: April 2022

Emission of carbon dioxide (CO2) becomes a main concern in battling issues of global warming. The strategy to reduce the concentration of CO2 could be achieved by implementing carbon capture and storage (CCS) technology such as adsorption by solid adsorbents. In this work, hydrazone containing adsorbent was prepared by radiation induced grafting of N-vinylformamide (NVF) onto polyethylene coated polypropylene (PE/PP) fibrous sheets and subsequent hydrazinolysis for CO2 capture. Hydrazinolysis of the amide group to hydrazone moieties was accelerated by the addition of ammonium salts. These newly prepared adsorbent was characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). The adsorption tests of pure CO2 and N2, and their mixture were carried using the gravimetric method. The result revealed that the obtained adsorbent was highly CO2 selective and attained remarkably higher CO2 sorption capacity of 3.1 mmol/g at 30 bar and room temperature compared to 0.3 mmol/g for amide-containing sample. The new adsorbent could be used for few repeated cycles with negligible loss in sorption capacity. Overall, the hydrazone-containing adsorbent has storing potential for CO2 capture, and more studies need to be conducted for further development.
Study of solution diversity in multi-objective optimization of storage ring lattice
Authors: Xu J. , Tan J. , Liu G. , Bai Z. , Wang L.
Published: April 2022

Evolutionary algorithms, including multi-objective genetic
algorithm (MOGA) and multi-objective particle swarm optimization
(MOPSO), have been widely used for storage ring lattice designs,
showing good performance in searching the optimal objective function
values (i.e. Pareto front). Mathematically, different variable
values can have the same objective function value, which is called
many-to-one mapping. Different from focusing on the convergence of
Pareto front, in this paper we study the diversity of variables in
the optimization of storage ring lattice and make a comparison
between MOGA and MOPSO. Two different lattices are taken as study
examples. The study shows that the lattice solutions with almost the
same objectives and different variables can show difference in some
storage ring properties, which is beneficial for lattice selection.
Besides, compared to MOPSO, MOGA gives a wider distribution of
optimal lattice solutions in the variable space, though both
algorithms can obtain almost the same Pareto front.
A facility for radiation hardness studies based on a medical cyclotron
Authors: Anders J. , Braccini S. , Carzaniga T.S. , Casolaro P. , Chatterjee M. , Dellepiane G. , Franconi L. , Halser L. , Ilg A. , Mateu I. , Meloni F. , Merlassino C. , Miucci A. , Müller R. , Rimoldi M. , Weber M.
Published: April 2022

The development of instrumentation for operation in
high-radiation environments represents a challenge in various
research fields, particularly in particle physics experiments and
space missions, and drives an ever-increasing demand for irradiation
facilities dedicated to radiation hardness studies. Depending on the
application, different needs arise in terms of particle type, energy
and dose rate. In this article, we present a versatile installation
based on a medical cyclotron located at the Bern University Hospital
(Inselspital), which is used as a controlled 18-MeV proton
source. This accelerator is used for daily production of medical
radioisotopes, as well as for multidisciplinary research, thanks to
a 6.5-meter long beam transfer line that terminates in an
independent bunker, dedicated only to scientific activities. The
facility offers a wide range of proton fluxes, due to an adjustable
beam current from approximately 10 pA to the micro-ampere range,
together with a series of steering and focusing magnets along the
beamline that allow for the beam spot to be focused down to a few
mm^2. The beamline can be instrumented with a variety of beam
monitoring detectors, collimators, and beam current measurement
devices to precisely control the irradiation conditions. The
facility also hosts a well equipped laboratory dedicated to the
characterisation of samples after irradiation. An experimental
validation of the irradiation setup, with proton fluxes ranging from
5×10^9 cm^-2s^-1 to
4×10^11 cm^-2s^-1, is reported.
Gel dressing based on type I collagen modified with oligourethane and silica for skin wound healing
Authors: Muñoz-González Pedro U , Lona-Ramos María C , Gutiérrez-Verdín Luis D , Luévano-Colmenero Guadalupe H , Tenorio-Rocha Fernando , García-Contreras René , González-García Gerardo , Rosillo-de la Torre Argelia , Delgado Jorge , Castellano Laura E , Mendoza-Novelo Birzabith
Published: April 2022

Cutaneous wound healing is a complex process that leads the skin reparation with the formation of scar tissue that typically lacks skin appendages. This fact drives us to find new strategies to improve regenerative healing of the skin. This study outlines, the contribution of colloidal silica particles and oligourethane crosslinking on the collagen material properties and the effect on skin wound healing in rats. We characterized the gel properties that are key for in-situ gelation, which is accomplished by the latent reactivity of oligourethane bearing blocked isocyanate groups to crosslink collagen while entrapping silica particles. The swelling/degradation behavior and the elastic modulus of the composite gel were consistent with the modification of collagen type I with oligourethane and silica. On the other hand, these gels were characterized as scaffold for murine macrophages and human stem cells. The application of a composite gel dressing on cutaneous wounds showed a histological appearance of the recovered skin as intact skin; featured by the epidermis, hair follicles, sebaceous glands, subcutaneous adipose layer, and dermis. The results suggest that the collagen-based composite dressings are promising modulators in skin wound healing to achieve a regenerative skin closure with satisfactory functional and aesthetic scars.
Priority areas for mixed-species mangrove restoration: the suitable species in the right sites
Authors: Su Jie , Yin Bingchao , Chen Luzhen , Gasparatos Alexandros
Published: April 2022

The rapid mangrove loss and fragmentation observed in the past decades have catalyzed numerous efforts to restore mangroves globally, but nearly half of these efforts fail or underperform. Planting the wrong mangrove species on the wrong site, and overrelying on mangrove monocultures are the main mistakes. Here, we develop a methodological approach that combines a Geographic Information System-based suitability analysis and landscape connectivity analysis to identify suitable areas for species-specific and mixed-species mangrove restoration, and priority areas in terms of patch importance. We apply this approach to the Large Xiamen Bay in southeast China. Results from the case study emphasize the critical need of considering species-specific characteristics in mangrove restoration planning and the spatial heterogeneity of priority areas for mixed-species restoration. We find that mangrove restoration could indeed increase landscape connectivity of mangrove habitats. Larger patches would have more significant effects on habitat connectivity, and several small patches could be considered as stepping stones to promote landscape-level connectivity. The proposed approach has various implications for mangrove restoration efforts both at the study site and in other parts of the world.
Global review of human waste-picking and its contribution to poverty alleviation and a circular economy
Authors: Morais Jandira , Corder Glen , Golev Artem , Lawson Lynda , Ali Saleem
Published: April 2022

Across the globe, the livelihood of millions of people relies on the recovery and sale of valuable materials previously discarded as waste. In developed countries, this is mainly incorporated into the official recycling and resources recovery sector, while in developing countries the informal waste picking activities often make a major contribution. Waste picking provides important opportunities to people who have few or no marketable skills and education and no alternative sources of income to survive. However, waste pickers’ living conditions remain deplorable, and their working conditions continue to be dangerous due to hazardous waste. Given the social, economic, and environmental benefits waste pickers bring, and particularly their contribution to circular economy goals in developing nations, the role of waste pickers has mostly been undervalued on the development agenda. This paper examines the literature on waste pickers around the world, their working and living conditions, and explores the issue of formalisation. A total of 45 papers published from 1994 to 2022 were reviewed, covering case studies on waste pickers from 27 different countries. We analyse the content of these papers based on a list of key themes: poverty, health, stigma, environmental factors, informality, and formalisation. We find that the informal status of waste pickers, and the question of them being formalised into a Municipal Solid Waste Management sector is discussed extensively in the literature, and we delve deeper into this theme. Formalisation can potentially bring considerable improvement to the lives of waste pickers, including legal recognition, safe working conditions and fair bargaining mechanisms. In practice however, we find that formalisation policies take significantly different forms from one country to another and often fail to provide these benefits.
Characterization of anomalous diffusion in one-dimensional quantum walks
Authors: Hegde Abhaya S , Chandrashekar C M
Published: April 2022

Quantum walks are known to propagate quadratically faster than their classical counterparts and are used to model dynamics in various quantum systems. The spread of the quantum walk in position space shows anomalous diffusion behavior. By controlling the action of quantum coin operation on the corresponding coin degree of freedom of the walker, one can demonstrate control over the diffusion behavior. In this work, we report different forms of coin operations on quantum walks exhibiting anomalous diffusion behavior. Homogeneous and accelerated quantum walks display superdiffusive behavior, whereas uncorrelated static and dynamic disorders in the evolution induce strong and weak localization of the particle indicating subdiffusive and normal diffusive behavior. The role played by the interference effects in the spreading of the walker has remained elusive and our aim in this work is to present the interplay between quantum coherence and mean squared displacement of the walker. We employ two reliable measures of coherence for conclusively establishing the role of quantum interference as the driving force behind the anomalous diffusive behavior in the dynamics of quantum walks.
Efficient algorithm for simulating particles in true quasiperiodic environments
Authors: Mendoza Sosa Alan Rodrigo , Kraemer Atahualpa S
Published: April 2022

We introduce an algorithm based on generalized dual method (GDM) to efficiently study the dynamics of a particle in quasiperiodic environments without the need to use periodic approximations or to save the information of the vertices that make up the quasiperiodic lattice. We show that the computation time and the memory required to find the tile in which a particle is located as a function of the distance R to the center of symmetry remains constant in our algorithm, while using the GDM directly both quantities go like R
2. This allows us to perform realistic simulations with low consumption of computational resources. The algorithm can be used to study any quasiperiodic lattice that can be produced by the cut-and-project method. Using this algorithm, we have calculated the free path length distribution in quasiperiodic Lorentz gases reproducing previous results and for systems with high symmetries at the Boltzmann–Grad limit. We have found for the Boltzmann–Grad limit, that the distribution of free paths depends on the rank r of the quasiperiodic system and not on its symmetry. The distribution as a function of the free path length l appears to be a combination of exponential decay and a power-law behavior. The latter seems to become important only for probabilities less than

(

2

r
−
2

r

(

r
+
1

)

)

−
1

, showing an exponential decaying free-path length distribution for r → ∞, similar to what is observed in disordered systems.
Number of distinct sites visited by a resetting random walker
Authors: Biroli Marco , Mori Francesco , Majumdar Satya N
Published: April 2022

We investigate the number V

p
(n) of distinct sites visited by an n-step resetting random walker on a d-dimensional hypercubic lattice with resetting probability p. In the case p = 0, we recover the well-known result that the average number of distinct sites grows for large n as ⟨V
0(n)⟩ ∼ n

d/2 for d < 2 and as ⟨V
0(n)⟩ ∼ n for d > 2. For p > 0, we show that ⟨V

p
(n)⟩ grows extremely slowly as

∼

log

(

n

)

d

. We observe that the recurrence-transience transition at d = 2 for standard random walks (without resetting) disappears in the presence of resetting. In the limit p → 0, we compute the exact crossover scaling function between the two regimes. In the one-dimensional case, we derive analytically the full distribution of V

p
(n) in the limit of large n. Moreover, for a one-dimensional random walker, we introduce a new observable, which we call imbalance, that measures how much the visited region is symmetric around the starting position. We analytically compute the full distribution of the imbalance both for p = 0 and for p > 0. Our theoretical results are verified by extensive numerical simulations.
Cartilage tissue engineering by extrusion bioprinting utilizing porous hyaluronic acid microgel bioinks
Authors: Flégeau Killian , Puiggali-Jou Anna , Zenobi-Wong Marcy
Published: April 2022

3D bioprinting offers an excellent opportunity to provide tissue-engineered cartilage to microtia patients. However, hydrogel-based bioinks are hindered by their dense and cell-restrictive environment, impairing tissue development and ultimately leading to mechanical failure of large scaffolds in vivo. Granular hydrogels, made of annealed microgels, offer a superior alternative to conventional bioinks, with their improved porosity and modularity. We have evaluated the ability of enzymatically crosslinked hyaluronic acid (HA) microgel bioinks to form mature cartilage in vivo. Microgel bioinks were formed by mechanically sizing bulk HA-tyramine hydrogels through meshes with aperture diameters of 40, 100 or 500 µm. Annealing of the microgels was achieved by crosslinking residual tyramines. Secondary crosslinked scaffolds were stable in solution and showed tunable porosity from 9% to 21%. Bioinks showed excellent rheological properties and were used to print different objects. Printing precision was found to be directly correlated to microgel size. As a proof of concept, freeform reversible embedding of suspended hydrogels printing with gelation triggered directly in the bath was performed to demonstrate the versatility of the method. The granular hydrogels support the homogeneous development of mature cartilage-like tissues in vitro with mechanical stiffening up to 200 kPa after 63 d. After 6 weeks of in vivo implantation, small-diameter microgels formed stable constructs with low immunogenicity and continuous tissue maturation. Conversely, increasing the microgel size resulted in increased inflammatory response, with limited stability in vivo. This study reports the development of new microgel bioinks for cartilage tissue biofabrication and offers insights into the foreign body reaction towards porous scaffolds implantation.