bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response of the seagrass Posidonia oceanica and its associated N2 fixers to high business‐as‐usual climate change scenario in winter
Authors: Agawin Nona S. R. , Gil Atorrasagasti Mª Guadalupe , Frank Comas Aida , Fernández‐Juárez Víctor , López‐Alforja Xabier , Hendriks Iris E. 
Published: April 2021

AbstractWe investigated the effects of increasing seawater temperature and CO2 concentration based on a high business‐as‐usual climate change scenario by year 2100 on the photosynthetic performance and productivity of Mediterranean seagrass Posidonia oceanica and alkaline phosphatase and N2‐fixing activities of microbes associated with different plant parts during winter when the plants may be thermally more vulnerable. Our results suggest that elevated CO2 and temperature benefit the overall photosynthetic performance of P. oceanica. Despite the benefits, the magnitude of respiration increased with elevated CO2 resulting in a negative carbon balance for P. oceanica in winter. This trend is contradictory to the general notion of decreased respiration in plants with increasing CO2, and warrants future investigation on the mechanisms behind the opposite trend. Changes of alkaline phosphatase activities found here may not be a direct consequence of the different treatments, but indirectly, through changes in the demand for dissolved inorganic phosphorus for N2 fixers. Of the several groups of N2 fixers tested for nifH expression (a proxy for activity of nitrogenase, the enzyme required for N2 fixation), only the unicellular N2‐fixing cyanobacterial phylotypes, UCYNB and UCYNC, actively transcribed with a positive nifH transcription response of UCYNC to elevated CO2 and temperature. Our results suggest that in future climate scenarios, the structure and diversity of N2 microbial communities associated with seagrasses may change and high‐light the importance of investigating the responses of different groups individually in their natural habitat substrates.
Self‐Assembly and Molecular Electrical Switching Property of Phthalocyanine‐Based Liquid‐Crystalline Poly(Styrene Sulfonic Acid) Compounds
Authors: Kong Weiwei , Tang Xinqiao , Chang Xiaolong , Zhuang Yu , Li Xin , Jia Yinggang , Meng Fanbao 
Published: April 2021

AbstractA series of phthalocyanine‐based liquid‐crystalline poly(styrene sulfonic acid) compounds (LCPCs) are synthesized using cholesterol, dicarboxylic acid, amino‐ zinc phthalocyanine, and polystyrene sulfonic acid. The chemical structure, thermal property, liquid‐crystalline behavior, direct current conductivity, and temperature‐controlled molecular electronic switch property are investigated by use of various techniques. The LCPCs show both columnar phase (Colh) induced by the phthalocyanine moieties and nematic discotic (Nd) phase formed by the collapse of the columnar phase structure. The temperature‐dependent conductivity of the LCPCs is associated with the activation energy evaluated by Broido's graphical procedure according to the thermogravimetric analytical curves. The LCPCs show low conductivity derived from 1D charge migration through phthalocyanine cores in the colh phase, but exhibit high conductivity due to 3D ionic charge transport in the Nd phase. A temperature‐controlled molecular electronic switch is fabricated on the basis of the temperature‐dependent conductivity property, which can be useful for some potential applications.
Sub‐20 nm Bilayer Hydrophilic Poly(Vinyl Pyrrolidone) Coatings for Antifouling Nanofiltration Membranes
Authors: Liu Wenna , Su Cuicui , Su Peipei , Yang Huidong , Lu Peng , Du Zhentao , Ye Yumin 
Published: April 2021

AbstractFouling is a major concern in membrane technology. Neutral hydrophilic coatings alleviate fouling on membrane surfaces by passively resisting the adsorption of foulants without altering the properties of membranes. Coatings, however, often result in a trade‐off of reduced water flux. Ultrathin hydrophilic coatings could minimize the influence on water flux, but its fabrication is challenging via traditional methods. Here, fabrication of sub‐20 nm bilayer hydrophilic coating is reported that is grafted onto nanofiltration (NF) membranes via a one‐step initiated chemical vapor deposition (iCVD) method. The iCVD coating is conducted by conformally depositing a crosslinked poly(vinyl pyrrolidone‐co‐ethylene glycol dimethacrylate) bottom layer on pretreated NF membrane, followed by in situ grafting of poly(vinyl pyrrolidone) homopolymer to further improve surface hydrophilicity. Both thickness and crosslinking degree of the bottom coating are systematically tailored to reduce its side effects on permeation rate and salt rejection. The modified NF membranes exhibit 99% lower microbial adhesion compared to the pristine membrane, with minor impact on permeation and salt rejection performance. The coating is also stable against continuous ultrasonication. The reported method is thus expected to shed light on facile novel ways of reducing membrane fouling in desalination and industrial wastewater treatment.
Development of a Zeolite/Polymer‐Based Hydrogel Composite through Photopolymerization for 3D Printing Application
Authors: Zhang Yijun , Liu Shaohui , Chen Hong , Josien Ludovic , Schrodj Gautier , Simon‐Masseron Angélique , Lalevée Jacques 
Published: April 2021

AbstractIn recent years, hydrogels have been widely applied in daily life and industry. More and more fillers have been combined with hydrogel to broaden their fields of application and improve their mechanical properties. However, there are few works about zeolite‐based hydrogel composites via photopolymerization. Hence, in this work, it is reported that the fabrication of hydrogel composites containing zeolite (FAU‐13X ≈ 40 wt%) under mild photopolymerization conditions (visible LED light irradiation, at room temperature, under air, and without any monomer purification). Markedly, compared to pure hydrogel, the elastic modulus (G′) of hydrogel composite contains 10% FAU‐13X increased by more than 100%. When the zeolite content reached 40%, the water swelling ratio in mass reached 120%, and that in volume remained at 150%. In addition, 3D patterns with flat surface are obtained through direct laser write as a lithography technique. This means these hydrogel composites can be applied in the field of water absorption materials and 3D printing.
Chemically Room Temperature Crosslinked Polyvinyl Alcohol (PVA) with Anomalous Microwave Absorption Characteristics
Authors: Bora Pritom J. , Anil Amith G. , Ramamurthy Praveen C. , Lee Yee Hui 
Published: April 2021

AbstractPolyvinyl alcohol (PVA) is a great interest polymer due to its excellent film‐forming, emulsifying, microwave dielectrics and adhesive properties. However, PVA is a water‐soluble synthetic polymer making it susceptible to environmental factors. In this work, PVA is crosslinked at room temperature using divinyl sulfone (DVS) as a crosslinker, and the obtained crosslinked PVA (XPVA) is water‐insoluble. Crosslinking mechanism is proposed, thermal and microwave dielectric properties of X‐PVA are studied. The studies revealed that X‐PVA has better thermal stability and microwave absorption properties. The obtained minimum reflection loss (RL) of X‐PVA is ‐23 dB (filler‐free) with entire X‐band (8.2–12.4 GHz) absorption bandwidth (RL ≤ ‐10 dB), indicating excellent microwave absorption properties. Artificial neural network (ANN) predicted RL of X‐PVA also matched well with the experimental data. Electromagnetic power simulation suggests that the microwave power absorption density due to the dielectric loss is intrinsically predominant in X‐PVA compared to the pristine PVA. Further, the ratio of electromagnetic energy to heat energy conversion power (absorption) of X‐PVA is much higher than pristine PVA, indicating the suitability for self‐powered devices. X‐PVA also fulfils many commercial requirements such as bulk level facile synthesis, large area fabrications, ultralight, and inexpensive.
Hydrogen‐Bonded Complexes of Star Polymers
Authors: Aliakseyeu Aliaksei , Dormidontova Elena E. , Sukhishvili Svetlana A. 
Published: April 2021

AbstractThe effect of molecular architecture, star versus linear, poly(ethylene oxide) (PEO) on the formation of hydrogen‐bonded complexes with linear poly(methacrylic acid) (PMAA) is investigated experimentally and rationalized theoretically. Isothermal titration calorimetry reveals that at pH 2.5 interpolymer complexes (IPCs) of PMMA with a 6‐arm star PEO (sPEO) contains ≈50% more polyacid than IPCs formed with linear PEO (lPEO). While the enthalpy of IPC formation is positive in both cases, its magnitude is ≈50% larger for sPEO/PMAA complexes that exhibit a lower dissociation constant than lPEO/polyacid complexes. These results are rationalized based on a higher localized density of hydrogen bonds formed between sPEO and the polyacid which prevents penetration of star molecules into PMAA coils. Accordingly, Fourier transform infrared results indicate approximately twofold excess of self‐associated >COOH units over intermolecularly bonded >COOH units in sPEO‐containing complexes. The excess of PMAA chains in IPCs and the percentage of self‐associated carboxylic groups in sPEO/PMAA complexes both increase with polyacid molecular weight. Other findings, including a positive entropy, hysteresis in composition at strongly acidic pH, and progressive equilibration of IPCs at increased pH are consistent with the critical role of charge and release of water molecules in the formation of sPEO/PMAA and lPEO/PMAA complexes.
Biological Membrane Asymmetry and its Role in Bone Mineralization
Authors: Clarke Ronald J. 
Published: April 2021

AbstractThe membranes of animal cells consist of a bilayer of lipid molecules (phospholipids and cholesterol) and embedded protein molecules. However, in living cells the phospholipids are not distributed equally between the bilayer's cytoplasmic and extracellular leaflets. Phosphatidylserine (PS) and phosphatidylethanolamine (PE) are concentrated in the membrane's inner leaflet, whereas phosphatidylcholine (PC) and sphingomyelin (SM) are concentrated in the outer leaflet. This non‐equilibrium situation is maintained by lipid pumps in the membrane, i.e., protein molecules which actively use energy in the form of ATP to transport lipids in both directions across the membrane. Pumps which transfer lipids from the external leaflet to the inner leaflet are termed flippases. Those that transfer lipids from the inner to the outer leaflet are termed floppases. The asymmetric distribution of PS is particularly important because of the negative charge of its polar head. This allows it to interact with divalent metal ions in the neighbouring solution. Although normally maintained on the cytoplasmic side of the membrane by a PS‐flippase, activation of scramblase proteins allows its distribution across the membrane to equilibrate, leading to PS exposure on the extracellular surface. In osteoblasts, the cells which produce bone, PS exposure also plays a key role in skeletal development. The negative charges of PS provides a template, attracting Ca2+ ions and promoting the deposition of hydroxyapatite Ca10(PO4)6(OH)2, the major mineral component of bone.
The Influence of Microstructure in PHB Non‐Woven Materials on Mechanical Behavior Under Tension
Authors: Morokov Egor , Zykova Anna , Tyubaeva Polina 
Published: April 2021

AbstractThis work focuses on the study of mechanical behavior of non‐woven scaffolds under tensile. The results are obtained in poly(3‐hydroxybutyrate) (PHB) scaffolds prepared by two technological approaches and various PHB concentration in molding solutions. The technological solutions provide electrospun fibrous structures with various fiber morphologies, which cause significant differences in the physico‐mechanical properties of non‐woven materials. Tensile strength of produced PHB scaffolds with different porosity and geometry of fibrous layer is in the range of 0.1 to 1.3 MPa and elongation at break from 3% to 9%. To visualize the evolution of the microstructure during tensile, optic microscopy and high‐frequency acoustic microscopy are applied.
Analysis of the Thermal Behavior of Materials for Orthopedic Heels
Authors: Cotoros Diana , Druga Corneliu , Repanovici Angela , Stanciu Anca 
Published: April 2021

AbstractThe present paper proposes an experiment meant to determine the change of dimensions that may occur due to the increase of temperature of the orthopedic heels. The 3D model is manufactured using ethylene‐vinyl acetyl, also known as EVA, a copolymer made of ethylene and vinyl acetyl, which is very flexible and light weighted, also impermeable and UV and shock resistant. Five of the most used materials are analyzed during the experiment Orange Support, Blue Comfort, Multicolor, Green Relax, and Yellow Soft. Dimensions measurements are also taken five times a day for 5 days and recorded in tables and diagrams using Excel tools.In order to perform a statistical analysis of the results, the F‐Anova test is used and applied upon the recorded values. The conclusion is that there is a significant change of dimensions in the orthopedic heels materials that might affect the comfort of the users in certain conditions.
Abrasive Erosion Behavior of Some Plastic Parts Obtained by 3D Printing
Authors: Hrituc Adelina , Slătineanu Laurenţiu , Boca Marius Andrei , Sover Alexandru , Nagîţ Gheorghe , Dodun Oana , Coteaţă Margareta , Mihalache Andrei 
Published: April 2021

AbstractThe properties of the material most often influence the use of a particular material to manufacture a part, and the quality reflected in part obtained behavior. In plastics, their diversity and specific characteristics, which are sometimes influenced by the additives used, do not ensure resistance to mechanical stress and some mechanical properties specific to metallic materials. For such reasons, the use of plastics is limited, but research and development in this area show that there is potential to improve plastics' properties. To observe the characteristics of a material and the performance in use it can have, laboratory tests and research are important, and the observations are beneficial. Experimental tests are designed and performed to evaluate the wear resistance of some samples obtained by 3D printing. By the mathematical processing of the results, it is possible to identify empirical mathematical models capable of providing information about the intensity of the influence of different factors on the abrasive wear resistance of the materials incorporated in the samples obtained by 3D printing.
Data Acquisition and Generative Design for a Smart Spinal Orthosis
Authors: Murzac Roman , Doicin Cristian‐Vasile , Ulmeanu Mihaela‐Elena 
Published: April 2021

AbstractThe design and development process of custom‐made medical devices is very complex and often requires the use of additive manufacturing to obtain a customer compliant product. One of the key stages, but also very time consuming in the development of bespoke medical products, is the data acquisition of the patients’ specific anatomy. The current research paper presents a detailed process of upper body data acquisition using 3D scanning protocols, with the goal of designing a custom smart spinal orthosis using generative design and additive manufacturing technologies. The initial captured cloud points are subjected successively to a series of surface manipulation and mesh optimization operations to generate the final working 3D model of the upper body. Each stage of the 3D model is obtained using a specific software application, as follows: *.DICOM images are generated using a 3D scanner software; *STL files are obtained by transforming initial files using MeshMixer software; *.STEP files are optimized using Fusion 360. Shape validation is done by 3D printing of a real scale upper body anatomical prototype using material extrusion. Authors also proposed a generative design process for the development of a personalized vertebral body from the construction of the smart spinal orthosis. The generative study is initialized with the following data: connection type, stress scenarios, material type (metals – Ti, Al, Steel; composites – ABS, PET, HIPS), and manufacturing technology (additive, subtractive, injection molding). A set of 49 converged outcomes is generated after running the study and three are selected for further research.
Design and Additive Technologies for Advanced Manufacturing: Best Practices
Authors: Laudante Elena , Giugliano Giovanna , Formati Fabrizio 
Published: April 2021

AbstractIn the current scenario, Additive Manufacturing has established itself as a technological tool of great interest to quickly and flexibly adapt the manufacturing system to the new production needs and market inputs. The aim of the paper is to identify possible future scenarios arising from the interaction between Industrial Design and Additive Technologies and to investigate the possibilities arising from the use of technologies in production. Through the recognition of best practices and representative case studies, the strengths and critical issues arising in the use of additive technologies will be highlighted in order to identify new configurations and design opportunities.
Biocycle between Design and Additive Manufacturing
Authors: Scognamiglio Ciro , Capece Sonia , De Luca Alessandro , Amendola Eugenio , Egido‐Villarreal Janitzio , Buono Mario 
Published: April 2021

AbstractThe paper describes the experience of research and experimentation conducted for the configuration of a new “Biocycle” bike conceived through eco‐friendly and bio‐inspired design methods and with the support of additive manufacturing (AM) technologies aimed to achieve a customized and flexible production. According to this logic, it is necessary to consider the AM as a valid support to both innovation and growth of many sectors in which creativity and design capacity play a strategic role for original solutions. The multidisciplinary approach and the collaboration between research institutes, companies, laboratories and universities, characterize the design and experimentation of the Biocycle. This has enabled the development of a new bicycle according to eco‐design and bio‐design criteria, by using recycled materials such as polyethylene terephthalate (PET), by introducing the principles of the environmental design into the definition of the entire product life cycle and by merging traditional production methods with AM to optimize the performance and reduce the overall weight, costs, and production time of the frame. To support the design phase, also a finite element (FE) model was developed. The aim is to obtain lightweight performing components with compact and ergonomic dimensions for the eco‐bike. This leads to the synthesis of new unconventional shapes and a better distribution of the material from the topological‐functional optimization analysis as well as AM.
Analyzing the Role of Magnetic Features in Additive Manufactured Scaffolds for Enhanced Bone Tissue Regeneration
Authors: De Santis Roberto , Papallo Ida , Onofrio Ilaria , Peluso Valentina , Gallicchio Vito , Rega Andrea , D'Antò Vincenzo , Improta Giovanni , Catauro Michelina , Gloria Antonio , Russo Teresa 
Published: April 2021

AbstractThe concept of magnetic guidance has opened a wide range of perspectives in the field of tissue regeneration. Accordingly, the aim of the current research is to design magnetic responsive scaffolds for enhanced bone tissue regeneration. Specifically, magnetic nanocomposite scaffolds are additively manufactured using 3D fibre deposition technique. The mechanical and magnetic properties of the fabricated scaffolds are first assessed. The role of magnetic features on the biological performances is properly analyzed.
New Strategies for the Development of Multifunctional Suture Threads
Authors: Tranquillo Elisabetta , Bollino Flavia 
Published: April 2021

AbstractSurgical site infection (SSI) is one of the most frequently reported types of hospital‐acquired infections, associated with severe morbidity and sometimes mortality. It leads to an increase in the clinical and economic burden of surgery, due to the direct costs incurred by prolonged hospitalization, diagnostic tests, outpatient visits, systemic antibiotic treatments, and often reoperations. The SSI is frequently caused by the suture threads material which can become an infection vector. The present mini‐review shows how the research is bringing new skills and knowledge in the design of new suture threads for SSI prevention and the wound healing process improvement.
Lean 4.0 Dynamic Tools for Polymeric Products Manufacturing in Industry 4.0
Authors: Dănuţ‐Sorin Ionel R. , Opran Constantin Gheorghe , Lamanna Giuseppe 
Published: April 2021

AbstractIn the polymer products industry, new technologies and Industry 4.0 concepts represent real solutions to increase efficiency and profitability through creating the intelligent and adaptable manufacturing system. At the same time, the existing manufacturing systems have made sustained efforts to implement Lean principles, techniques and tools to achieve process efficiency by eliminating waste and continuously improving performance. The production system architecture consists of active production resources, which participate directly in the production process flow, and passive elements, which have a supporting role. In Industry 4.0, these elements form a dynamic cyber‐physical production subsystem, through which different manufacturing solutions can be managed. Updating Lean production systems to Industry 4.0 level is obtained by implementing Lean tools and principles to the cyber‐physical system. This work presents the results of research on transforming a Lean instrument a into a Lean 4.0 solution, applicable to manufacturing cells processes, in an Industry 4.0 manufacturing system.
Experimental and Analytical Investigation of the Shear Fracture Behavior of Bonded Joints
Authors: Perrella Michele , Berardi Valentino Paolo , Armentani Enrico 
Published: April 2021

AbstractThe demand of adhesive bonding as technique for the strengthening of existing structures is currently increasing in many engineering fields. Therefore, the prediction of bonded joints fracture behavior is an open issue for the structural safety of repairs. With this aim, a cohesive zone approach is adopted to determine the shear fracture behavior of epoxy resin interface layer of end notched flexure (ENF) specimen. Experimental tangential slip displacements of adherends are evaluated by digital image correlation (DIC) analysis. The identified traction‐separation law can be implemented in a finite element (FE) code to predict the decohesion of adhesively bonded joints.