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Open AccessArticle
Energy Consumption and Greenhouse Gas Emissions of Nickel Products
Energies 2020, 13(21), 5664; https://doi.org/10.3390/en13215664 (registering DOI) - 29 Oct 2020
Abstract
The primary energy consumption and greenhouse gas emissions from nickel smelting products have been assessed through case studies using a process model based on mass and energy balance. The required primary energy for producing nickel metal, nickel oxide, ferronickel, and nickel pig iron [...] Read more.
The primary energy consumption and greenhouse gas emissions from nickel smelting products have been assessed through case studies using a process model based on mass and energy balance. The required primary energy for producing nickel metal, nickel oxide, ferronickel, and nickel pig iron is 174 GJ/t alloy (174 GJ/t contained Ni), 369 GJ/t alloy (485 GJ/t contained Ni), 110 GJ/t alloy (309 GJ/t contained Ni), and 60 GJ/t alloy (598 GJ/t contained Ni), respectively. Furthermore, the associated GHG emissions are 14 tCO2-eq/t alloy (14 tCO2-eq/t contained Ni), 30 t CO2-eq/t alloy (40 t CO2-eq/t contained Ni), 6 t CO2-eq/t alloy (18 t CO2-eq/t contained Ni), and 7 t CO2-eq/t alloy (69 t CO2-eq/t contained Ni). A possible carbon emission reduction can be observed by comparing ore type, ore grade, and electricity source, as well as allocation strategy. The suggested process model overcomes the limitation of a conventional life cycle assessment study which considers the process as a ‘black box’ and allows for an identification of further possibilities to implement sustainable nickel production. Full article
(This article belongs to the Special Issue Carbon Footprinting and Life Cycle Assessment)
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Open AccessArticle
Ciranda—An Inclusive Floor Seating Positioning System and Social Enterprise
Int. J. Environ. Res. Public Health 2020, 17(21), 7942; https://doi.org/10.3390/ijerph17217942 (registering DOI) - 29 Oct 2020
Abstract
One of the first challenges for many children with physical disabilities is to sit independently. A floor seating positioning system enables this milestone, helping a child to maintain eye level with other children, play and learn on the floor, rectify his or her [...] Read more.
One of the first challenges for many children with physical disabilities is to sit independently. A floor seating positioning system enables this milestone, helping a child to maintain eye level with other children, play and learn on the floor, rectify his or her posture, and, therefore, helps to include the child within his or her social spectrum. Ciranda is the first comprehensive floor seat solution in Brazil to attend to those needs. The project collected anthropometric data from 370 children who were unable to sit without support. A sample of 37 families of these children was visited, observed, and interviewed. A project requirement compiled key insights from the field data to support a multidisciplinary team of collaborators to co-design solutions. The project resulted in two floor seating positioning systems to attend to different needs. One is a social enterprise where the children’s parents and the community build the seat while the child in need and his or her friends engage in entertainment. The other is a salable seat that helps to raise funds for the social enterprise. The model also unravels other challenges common to assistive technologies, such as access to a device and training for the use and maintenance of the device. Full article
(This article belongs to the Special Issue Assistive Technologies for Children, Young People and Adults)
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Open AccessArticle
Electrospinning/Electrospray of Ferrocene Containing Copolymers to Fabricate ROS-Responsive Particles and Fibers
Polymers 2020, 12(11), 2520; https://doi.org/10.3390/polym12112520 (registering DOI) - 29 Oct 2020
Abstract
We demonstrate an electrospray/electrospinning process to fabricate stimuli-responsive nanofibers or particles that can be utilized as stimuli-responsive drug-loaded materials. A series of random copolymers consisting of hydrophobic ferrocene monomers and hydrophilic carboxyl groups, namely poly(ferrocenylmethyl methacrylate-r-methacrylic acid) [poly(FMMA-r-MA)] with [...] Read more.
We demonstrate an electrospray/electrospinning process to fabricate stimuli-responsive nanofibers or particles that can be utilized as stimuli-responsive drug-loaded materials. A series of random copolymers consisting of hydrophobic ferrocene monomers and hydrophilic carboxyl groups, namely poly(ferrocenylmethyl methacrylate-r-methacrylic acid) [poly(FMMA-r-MA)] with varied composition, was synthesized with free radical copolymerization. The morphologies of the resulting objects created by electrospray/electrospinning of the poly(FMMA-r-MA) solutions were effectively varied from particulate to fibrous structures by control of the composition, suggesting that the morphology of electrosprayed/electrospun copolymer objects was governed by its composition and hence, interaction with the solvent, highlighting the significance of the balance of hydrophilicity/hydrophobicity of the copolymer chain to the assembled structure. Resulting particles and nanofibers exhibited largely preserved responsiveness to reactive oxygen species (ROS) during the deposition process, opening up the potential to fabricate ROS-sensitive material with various desirable structures toward different applications. Full article
(This article belongs to the Special Issue Advances in Polymer Nanofibers)
Open AccessArticle
Effect of Treadmill Exercise and Trans-Cinnamaldehyde against d-Galactose- and Aluminum Chloride-Induced Cognitive Dysfunction in Mice
Brain Sci. 2020, 10(11), 793; https://doi.org/10.3390/brainsci10110793 (registering DOI) - 29 Oct 2020
Abstract
Mild cognitive impairment (MCI) generally refers to impairment in cognition above that which accompanies the normal age-related cognitive decline and has attracted attention in recent years. Trans-cinnamaldehyde (TCA), which is isolated from cinnamon, has anti-inflammatory and antioxidant properties. Treadmill exercise also has diverse [...] Read more.
Mild cognitive impairment (MCI) generally refers to impairment in cognition above that which accompanies the normal age-related cognitive decline and has attracted attention in recent years. Trans-cinnamaldehyde (TCA), which is isolated from cinnamon, has anti-inflammatory and antioxidant properties. Treadmill exercise also has diverse positive effects. The purpose of this study was to investigate the combination effects of TCA and treadmill exercise on learning and memory in a cognitive impairment mouse induced by a combination of d-galactose (d-gal) and aluminum chloride (AlCl3). We found that exercise and TCA attenuated cognitive impairment in mice with induced MCI. This effect was further increased by costimulation of exercise and TCA. To clarify the mechanisms of the positive effects of TCA and exercise, we analyzed the nuclear factor erythroid 2-related factor (Nrf2) and related signaling pathways. We found that TCA and exercise upregulated Nrf2, NAD(P)H dehydrogenase quinone 1 (NQO-1), heme oxygenase 1 (HO-1), and superoxide dismutase 1 (SOD-1); this suggests that TCA and exercise attenuate cognitive dysfunction by reducing oxidative stress. We also found that Nrf2-related signaling pathways, i.e., the AMP-activated protein kinase (AMPK)/Nrf2 and SIRT1/PGC-1a/Nrf2-ARE pathways, exerted antioxidant effects. Together, these results suggest that costimulation with TCA and exercise may be a therapeutic candidate for mild cognitive impairment. Full article
(This article belongs to the Section Molecular and Cellular Neuroscience)
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Open AccessArticle
Halogenated Diazabutadiene Dyes: Synthesis, Structures, Supramolecular Features, and Theoretical Studies
Molecules 2020, 25(21), 5013; https://doi.org/10.3390/molecules25215013 (registering DOI) - 29 Oct 2020
Abstract
Novel halogenated aromatic dichlorodiazadienes were prepared via copper-mediated oxidative coupling between the corresponding hydrazones and CCl4. These rare azo-dyes were characterized using 1H and 13C NMR techniques and X-ray diffraction analysis for five halogenated dichlorodiazadienes. Multiple non-covalent halogen···halogen interactions [...] Read more.
Novel halogenated aromatic dichlorodiazadienes were prepared via copper-mediated oxidative coupling between the corresponding hydrazones and CCl4. These rare azo-dyes were characterized using 1H and 13C NMR techniques and X-ray diffraction analysis for five halogenated dichlorodiazadienes. Multiple non-covalent halogen···halogen interactions were detected in the solid state and studied by DFT calculations and topological analysis of the electron density distribution within the framework of Bader’s theory (QTAIM method). Theoretical studies demonstrated that non-covalent halogen···halogen interactions play crucial role in self-assembly of highly polarizable dichlorodiazadienes. Thus, halogen bonding can dictate a packing preference in the solid state for this class of dichloro-substituted heterodienes, which could be a convenient tool for a fine tuning of the properties of this novel class of dyes. Full article
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Open AccessArticle
Aspects of Digitalization and Related Impact on Green Tourism in European Countries
Information 2020, 11(11), 507; https://doi.org/10.3390/info11110507 (registering DOI) - 29 Oct 2020
Abstract
The digital world requires the implementation of new technologies and customer-driven business transformation. As the tourism sector may experience unanticipated ways of developing new technologies due to the current global health crisis, the standard travel experience could be changed. The main aim of [...] Read more.
The digital world requires the implementation of new technologies and customer-driven business transformation. As the tourism sector may experience unanticipated ways of developing new technologies due to the current global health crisis, the standard travel experience could be changed. The main aim of this study was to analyze the influence of digitalization and tourists’ preferences in terms of accommodation and economic well-being implying sustainability. This paper applied a regression analysis and principal component analysis to achieve the above objective. Research exposed the fact that tourists’ preferences towards green destinations and ecological accommodation establishments, as well as Internet use in travel planning, may have a significant influence on the sustainability of tourism. This study identified behavioral models of 30 European countries from the sustainable tourism and digitalization perspective and made recommendations on economic and social policy measures to ensure the sustainable nature of tourism activity. Full article
(This article belongs to the Special Issue Green Marketing)
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Open AccessFeature PaperReview
Revealing Plasma Membrane Nano-Domains with Diffusion Analysis Methods
Membranes 2020, 10(11), 314; https://doi.org/10.3390/membranes10110314 (registering DOI) - 29 Oct 2020
Abstract
Nano-domains are sub-light-diffraction-sized heterogeneous areas in the plasma membrane of cells, which are involved in cell signalling and membrane trafficking. Throughout the last thirty years, these nano-domains have been researched extensively and have been the subject of multiple theories and models: the lipid [...] Read more.
Nano-domains are sub-light-diffraction-sized heterogeneous areas in the plasma membrane of cells, which are involved in cell signalling and membrane trafficking. Throughout the last thirty years, these nano-domains have been researched extensively and have been the subject of multiple theories and models: the lipid raft theory, the fence model, and the protein oligomerization theory. Strong evidence exists for all of these, and consequently they were combined into a hierarchal model. Measurements of protein and lipid diffusion coefficients and patterns have been instrumental in plasma membrane research and by extension in nano-domain research. This has led to the development of multiple methodologies that can measure diffusion and confinement parameters including single particle tracking, fluorescence correlation spectroscopy, image correlation spectroscopy and fluorescence recovery after photobleaching. Here we review the performance and strengths of these methods in the context of their use in identification and characterization of plasma membrane nano-domains. Full article
(This article belongs to the Special Issue Dynamics and Nano-Organization in Plasma Membranes)
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Open AccessArticle
Effect of Road Traffic on Air Pollution. Experimental Evidence from COVID-19 Lockdown
Sustainability 2020, 12(21), 8984; https://doi.org/10.3390/su12218984 (registering DOI) - 29 Oct 2020
Abstract
The increasing concentration of human activities in cities has been leading to a worsening in air quality, thus negatively affecting the lives and health of humans living in urban contexts. Transport is one of the main sources of pollution in such environments. Several [...] Read more.
The increasing concentration of human activities in cities has been leading to a worsening in air quality, thus negatively affecting the lives and health of humans living in urban contexts. Transport is one of the main sources of pollution in such environments. Several local authorities have therefore implemented strict traffic-restriction measures. The aim of this paper is to evaluate the effectiveness and limitations of these interventions, by analyzing the relationship between traffic flows and air quality. The used dataset contains concentrations of NO, NO2, NOx and PM10, vehicle counts and meteorology, all collected during the COVID-19 lockdown in the city of Padova (Italy), in which severe limitations to contain the spread of the virus simulated long and large-scale traffic restrictions in normal conditions. In particular, statistical tests, correlation analyses and multivariate linear regression models were applied to non-rainy days in 2020, 2018 and 2017, in order to isolate the effect of traffic. Analysis indicated that vehicle flows significantly affect NO, NO2, and NOx concentrations, although no evidence of a relationship between traffic and PM10 was highlighted. According to this perspective, measures to limit traffic flows seem to be effective in improving air quality only in terms of reducing nitrogen oxide. Full article
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Open AccessEditorial
On a Magical Mystery Tour of Green Insecticide Research: Current Issues and Challenges
Molecules 2020, 25(21), 5014; https://doi.org/10.3390/molecules25215014 (registering DOI) - 29 Oct 2020
Abstract
The Editorial outlines recent research advances in green insecticide research. Particular attention is devoted to studies shedding light on the modes of action and non-target toxicity of natural substances of plant origin. Research focusing on the development of new formulations (including those relating [...] Read more.
The Editorial outlines recent research advances in green insecticide research. Particular attention is devoted to studies shedding light on the modes of action and non-target toxicity of natural substances of plant origin. Research focusing on the development of new formulations (including those relating to nano-objects) to magnify the effectiveness and stability of green insecticides in the field represents key advances. Herein, a carefully reviewed selection of cutting edge articles about green pesticide development recently published in Molecules is presented. The impact of sub-lethal doses of green insecticides on insect behavioral traits is still overlooked, representing a timely challenge for further research. Full article
(This article belongs to the Section Natural Products Chemistry)
Open AccessArticle
Antimicrobial Resistance of Coagulase-Positive Staphylococcus Isolates Recovered in a Veterinary University Hospital
Antibiotics 2020, 9(11), 752; https://doi.org/10.3390/antibiotics9110752 (registering DOI) - 29 Oct 2020
Abstract
The Staphylococcus pseudintermedius group (SIG) is an emerging threat in veterinary medicine, particularly methicillin-resistant (MRSP) isolates, which are frequently associated with multidrug resistance. Reliable identification of SIG members is critical to establish correct antimicrobial treatments. However, information on the molecular epidemiology and antimicrobial [...] Read more.
The Staphylococcus pseudintermedius group (SIG) is an emerging threat in veterinary medicine, particularly methicillin-resistant (MRSP) isolates, which are frequently associated with multidrug resistance. Reliable identification of SIG members is critical to establish correct antimicrobial treatments. However, information on the molecular epidemiology and antimicrobial resistance patterns of MRSP in some regions is still limited. This study aimed to assess the antimicrobial resistance of SIG isolates recovered from animals at the Veterinary Teaching Hospital of Complutense University of Madrid (Spain) during a 10-year period (2007–2016). A total of 139 selected Staphylococcus isolates were subjected to species-level identification by different bioanalytical techniques (PCR, VITEK, MALDI-TOF) and subsequent antimicrobial susceptibility testing. Methicillin-resistant isolates (n = 20) were subjected to whole genome sequencing for further characterization of their antibiotic resistance determinants. Our results showed that there was a good correlation between PCR and MALDI-TOF identification, whereas VITEK showed very divergent results, thus confirming MALDI-TOF as a good alternative for species-level identification of coagulase-positive staphylococci. Notably, S. pseudintermedius, including the epidemic MRSP genotype ST71, was the only SIG species found among canine isolates. In addition, we found a high prevalence of multidrug resistance and resistance to fluoroquinolones, cephalosporins and macrolides. Finally, diverse genes associated with antibiotic resistance were detected among MRSP isolates, although the genetic basis of some of the resistant phenotypes (particularly to fluoroquinolones) could not be determined. In conclusion, our study reveals the circulation of MRSP in the veterinary setting in Spain, thus highlighting the emerging threat posed by this bacterial group and the need for further epidemiological surveillance. Full article
Open AccessArticle
Influence of Different Types of Land Use on the Contents of Potentially Toxic Elements and De-Icing Salts in Roadside Soils and Trees in Urban Areas
Sustainability 2020, 12(21), 8985; https://doi.org/10.3390/su12218985 (registering DOI) - 29 Oct 2020
Abstract
In order to manage the urban environment and reduce pollution, it is essential to determine potentially toxic elements and de-icing salts in roadside soils and plants, which are major components of green infrastructure. A field study was conducted to elucidate the influence of [...] Read more.
In order to manage the urban environment and reduce pollution, it is essential to determine potentially toxic elements and de-icing salts in roadside soils and plants, which are major components of green infrastructure. A field study was conducted to elucidate the influence of land use on potentially toxic elements and deicing salts in roadside soil and trees in urban areas. The effect of land use was determined in commercial, residential, industrial, and green areas of Cheongju city. The roadside soil and plant samples were collected from four different sites along a major roadway in the city. The chemical parameters determined were pH, electronic conductivity, potentially toxic elements (Cd, Cu, Zn, Cr, As, Pb, Ni), and de-icing salts (Na, Ca, Mg). The pH, electronic conductivity, potentially toxic elements (except copper), and deicing salt values were significantly (p < 0.05) affected by the land use. On the other hand, the heavy metal (except zinc and nickel) levels in roadside tree leaves (Ginkgo biloba) were not affected by the different land use, whereas the deicing salt levels were significantly different (p < 0.05). The enrichment factor (EF) of potentially toxic elements was found to be lower than that of de-icing salts with the highest values of sodium in green areas and of magnesium in commercial areas. These results provide information on the implications of land use, including the surrounding area of influenced roadside soil and plant chemistry for the urban ecosystem. Full article
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Open AccessArticle
Chemical Investigation and Screening of Anti-Proliferative Activity on Human Cell Lines of Pure and Nano-Formulated Lavandin Essential Oil
Pharmaceuticals 2020, 13(11), 352; https://doi.org/10.3390/ph13110352 (registering DOI) - 29 Oct 2020
Abstract
Lavandin essential oil (LEO), a natural sterile hybrid obtained by crossbreeding L. angustifolia × L. latifolia, is mainly composed by active components belonging to the family of terpenes endowed with relevant anti-proliferative activity, which can be enhanced by proper application of nanotechnology. In [...] Read more.
Lavandin essential oil (LEO), a natural sterile hybrid obtained by crossbreeding L. angustifolia × L. latifolia, is mainly composed by active components belonging to the family of terpenes endowed with relevant anti-proliferative activity, which can be enhanced by proper application of nanotechnology. In particular, this study reports the chemical characterization and the screening of the anti-proliferative activity on different human cell lines of pure and nano-formulated lavandin essential oil (EO). LEO and its formulation (NanoLEO) were analyzed by HS/GC-MS (Headspace/Gas Chromatography-Mass Spectrometry) to describe and compare their chemical volatile composition. The most abundant compounds were linalool and 1,8-cineole (LEO: 28.6%; 27.4%) (NanoLEO: 60.4%; 12.6%) followed by α-pinene (LEO: 9.6%; NanoLEO: 4.5%), camphor (LEO: 6.5%; NanoLEO: 7.0%) and linalyl acetate (LEO: 6.5%; NanoLEO: 3.6%). The cytotoxic effects of LEO and NanoLEO were investigated on human neuroblastoma cells (SHSY5Y), human breast adenocarcinoma cells (MCF-7), human lymphoblastic leukemia cells (CCRF CEM), human colorectal adenocarcinoma cells (Caco-2) and one normal breast epithelial cell (MCF10A) by the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide)-assay. Caco-2, MCF7 and MCF10A normal cells resulted more resistant to the treatment with LEO, while CCRF-CEM and SHSY5Y cells were more sensitive. The antiproliferative effect of LEO resulted amplified when the essential oil was supplied as nanoformulation, mainly in Caco-2 cells. Scanning and transmission electron microscopy investigations were carried out on Caco-2 cells to outline at ultrastructural level possible affections induced by LEO and NanoLEO treatments. Full article
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Open AccessReview
Biomarkers in Anderson–Fabry Disease
Int. J. Mol. Sci. 2020, 21(21), 8080; https://doi.org/10.3390/ijms21218080 (registering DOI) - 29 Oct 2020
Abstract
Fabry disease is a rare lysosomal storage disorder caused by a deficiency of α-galactosidase A, resulting in multisystemic involvement. Lyso-Gb3 (globotriaosylsphingosine), the deacylated form of Gb3, is currently measured in plasma as a biomarker of classic Fabry disease. Intensive research of biomarkers has [...] Read more.
Fabry disease is a rare lysosomal storage disorder caused by a deficiency of α-galactosidase A, resulting in multisystemic involvement. Lyso-Gb3 (globotriaosylsphingosine), the deacylated form of Gb3, is currently measured in plasma as a biomarker of classic Fabry disease. Intensive research of biomarkers has been conducted over the years, in order to detect novel markers that may potentially be used in clinical practice as a screening tool, in the context of the diagnostic process and as an indicator of response to treatment. An interesting field of application of such biomarkers is the management of female heterozygotes who present difficulty in predictable clinical progression. This review aims to summarise the current evidence and knowledge about general and specific markers that are actually measured in subjects with confirmed or suspected Fabry disease; moreover, we report potential novel markers such as microRNAs. Recent proteomic or metabolomic studies are in progress bringing out plasma proteome profiles in Fabry patients: this assessment may be useful to characterize molecular pathology of the disease, to improve diagnostic process, and to monitor response to treatment. The management of Fabry disease may be improved by the identification of biomarkers that reflect clinical course, severity, and the progression of the disease. Full article
(This article belongs to the Special Issue Biomarkers in Rare Diseases)
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Open AccessReview
Drug Repurposing for Triple-Negative Breast Cancer
J. Pers. Med. 2020, 10(4), 200; https://doi.org/10.3390/jpm10040200 (registering DOI) - 29 Oct 2020
Abstract
Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancer which presents a high rate of relapse, metastasis, and mortality. Nowadays, the absence of approved specific targeted therapies to eradicate TNBC remains one of the main challenges in clinical practice. Drug [...] Read more.
Triple-negative breast cancer (TNBC) is the most aggressive type of breast cancer which presents a high rate of relapse, metastasis, and mortality. Nowadays, the absence of approved specific targeted therapies to eradicate TNBC remains one of the main challenges in clinical practice. Drug discovery is a long and costly process that can be dramatically improved by drug repurposing, which identifies new uses for existing drugs, both approved and investigational. Drug repositioning benefits from improvements in computational methods related to chemoinformatics, genomics, and systems biology. To the best of our knowledge, we propose a novel and inclusive classification of those approaches whereby drug repurposing can be achieved in silico: structure-based, transcriptional signatures-based, biological networks-based, and data-mining-based drug repositioning. This review specially emphasizes the most relevant research, both at preclinical and clinical settings, aimed at repurposing pre-existing drugs to treat TNBC on the basis of molecular mechanisms and signaling pathways such as androgen receptor, adrenergic receptor, STAT3, nitric oxide synthase, or AXL. Finally, because of the ability and relevance of cancer stem cells (CSCs) to drive tumor aggressiveness and poor clinical outcome, we also focus on those molecules repurposed to specifically target this cell population to tackle recurrence and metastases associated with the progression of TNBC. Full article
(This article belongs to the Special Issue Recent Developments in Cancer Systems Biology)
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Open AccessReview
A Study on the Tribological Performance of Nanolubricants
Processes 2020, 8(11), 1372; https://doi.org/10.3390/pr8111372 (registering DOI) - 29 Oct 2020
Abstract
In recent years, the tribology field has expanded with the advent of nanolubrication. Nanolubricants are the name given to the dispersion of nanoparticles in a base oil, and has attracted researchers due to its potential application. In addition to being used in the [...] Read more.
In recent years, the tribology field has expanded with the advent of nanolubrication. Nanolubricants are the name given to the dispersion of nanoparticles in a base oil, and has attracted researchers due to its potential application. In addition to being used in the tribology field, nanoparticles are also used for medical, space, and composites purposes. The addition of nanoparticles in base oils is promising because it enhances specific tribological characteristics including wear-resistance and friction, and the most important reason is that the majority of them are environmentally friendly. This paper reviews the tribological effect of various nanoparticles as lubricant additives. Parameters of nanoparticles that affect tribological performance, the technique to enhance stability, and lubrication mechanism that is currently believed to function will be delineated in detail. Moreover, this review facilitates an understanding of the role of various nanoparticles, which helps in developing and designing suitable nanolubricants for various applications. Full article
(This article belongs to the Section Materials Processes)
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Open AccessFeature PaperArticle
Influence of the Miniaturisation Effect on the Effective Stiffness of Lattice Structures in Additive Manufacturing
Metals 2020, 10(11), 1442; https://doi.org/10.3390/met10111442 (registering DOI) - 29 Oct 2020
Abstract
Thin-walled and cellular structures are characterised by superior lightweight potential due to their advantageous stiffness to weight ratio. They find particular interest in the field of additive manufacturing due to robust and reproducible manufacturability. However, the mechanical performance of such structures strongly depends [...] Read more.
Thin-walled and cellular structures are characterised by superior lightweight potential due to their advantageous stiffness to weight ratio. They find particular interest in the field of additive manufacturing due to robust and reproducible manufacturability. However, the mechanical performance of such structures strongly depends on the manufacturing process and resultant geometrical imperfections such as porosity, deviations in strut thickness or surface roughness, for which an understanding of their influence is crucially needed. So far, many authors conducted empirical investigations, while analytical methods are rarely applied. In order to obtain efficient design rules considering both mechanical properties and process induced characteristics, analytical descriptions are desirable though. Available analytical models for the determination of effective properties are mostly based on the simple advancement of beam theories, mostly ignoring manufacturing characteristics that, however, strongly influence the mechanical properties of additive manufactured thin-walled structures. One example is the miniaturisation effect, a microstructural effect that has been identified as one of the main drivers of the effective elasto-plastic properties of lightweight structures processed by additive manufacturing. The current work highlights the need to quantify further microstructural effects and to encourage combining them into mesostructural approaches in order to assess macrostructural effective properties. This multi-scale analysis of lattice structures is performed through a comparison between effective stiffness calculated through an analytical approach and compression tests of lattice structures, coupled with an investigation of the arrangement of their struts. In order to cover different potential loading scenarios, bending-dominated and stretch-dominated lattice structures made of the commonly used materials 316L and Ti6Al4V are considered, whereby the impact of microstructural phase transformation during processing is taken into account. Full article
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Open AccessArticle
Disparities between Rural and Urban Areas of the Central Region of Saudi Arabia in the Utilization and Time-Centeredness of Emergency Medical Services
Int. J. Environ. Res. Public Health 2020, 17(21), 7944; https://doi.org/10.3390/ijerph17217944 (registering DOI) - 29 Oct 2020
Abstract
The purpose of this study was to explore differences in characteristics of missions dispatched by Emergency Medical Services (EMS) between rural and urban areas of Riyadh province in Saudi Arabia (SA). It also aimed at identifying weaknesses related to utilization and Response Time [...] Read more.
The purpose of this study was to explore differences in characteristics of missions dispatched by Emergency Medical Services (EMS) between rural and urban areas of Riyadh province in Saudi Arabia (SA). It also aimed at identifying weaknesses related to utilization and Response Time (RT). The study retrospectively evaluated 146,639 completed missions in 2018 by measuring the utilization rate in rural and urban areas. The study shows there are six times more ambulance crews available for rural areas compared to urban. There were 22.1 missions per 1000 urban inhabitants and 11.2 missions per 1000 in rural areas. The median RT for high urgent trauma cases was 20.2 min in rural compared to 15.2 min in urban areas (p < 0.001). In urban areas, the median RT for high urgent medical cases was 16.1 min, while it was 15.2 min for high urgent trauma cases. Around 62.3% of emergency cases in urban and 56.5% in rural areas were responded to within 20.00 min. Women utilized EMS less frequently. The RT was increased in urban areas compared to previous studies. The RT in the central region of SA has been identified as equal, or less than 20.00 min in 62.4% of all emergency cases. To further improve adherence to the 20′ target, reorganizing the lowest urgent cases in the rural areas seems necessary. Full article
(This article belongs to the Special Issue Emergency Medical Services Research)
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Open AccessArticle
Optimization of RNA In Situ Hybridization for mRNA Localization Detection in Mature Tissue of Cucumber Seedlings
Plants 2020, 9(11), 1461; https://doi.org/10.3390/plants9111461 (registering DOI) - 29 Oct 2020
Abstract
Cucumber (Cucumis sativus L.) is one of the main vegetable crops in China. The physiological cultivation mechanism and gene function characteristics of cucumber are of great significance to the construction of modern agriculture. Due to the low genetic transformation rate of cucumber, [...] Read more.
Cucumber (Cucumis sativus L.) is one of the main vegetable crops in China. The physiological cultivation mechanism and gene function characteristics of cucumber are of great significance to the construction of modern agriculture. Due to the low genetic transformation rate of cucumber, only in situ hybridization, which does not involve the progress of gene modified transformation, is convenient to study mRNA localization, so it is more suitable for determination on mRNA localization in the mature tissue of cucumber. At present, the existing in situ hybridization technology system is more suitable for cucumber meristem than for the mature tissue of cucumber seedlings. Therefore, we optimized the traditional plant in situ hybridization protocol. Taking a known gene CsNPF7.2 (Nitrate Transporter Families protein) as an example, we then optimized the steps of plant tissue culture, gene probe preparation, plant material sampling and fixation, preparation of cross section, hybridization pretreatment, hybridization incubation, chromogenic reaction, microscopy examination, and treatment after reaction termination in order to obtain a new RNA in situ hybridization technique suitable for identification on mRNA localization in mature tissues of cucumber seedlings. This optimized technique will ensure the yield of probes, the integrity of RNA molecules, and the clarity and integrity of plant tissue structure, which is conducive to the study of gene function and screening of key genes in cucumber. Full article
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