bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat-Treatment of Aluminium-Nickel Composite Cold Sprayed Coating
Authors: Winnicki Marcin , Jasiorski Marek , Baszczuk Agnieszka , Korzeniowski Marcin
Published: June 2020

Intermetallic compounds, especially aluminides, show good high-temperature strength, oxidation resistance, high melting points, and thus have received considerable attention as potential substitutes for superalloys in high-temperature applications. Aluminides are especially interesting because they are stable up to the critical temperature of ordering, which is close to the melting temperature. In the Al-Ni system, the most studied intermetallics are Ni3Al, NiAl and NiAl3. In the presented study, Al and Ni powders were mixed together with Al2O3 in various proportions to produce dense coatings by low-temperature cold spraying. Two types of post-deposition treatments were applied to produce aluminides, namely furnace heating and resistance spot welding. The former caused a long time diffusion while the latter a self-propagating high temperature synthesis. Both heating methods enabled formations of intermetallic phases. However, the furnace heating provides high porosity. The microstructure of the samples was analyzed by SEM (scanning electron microscope), EDS (energy dispersive X-ray spectroscopy) and XRD (X-ray diffraction) together with microhardness measurements.
Analysis of the Phase Stability of LiMO2 Layered Oxides (M = Co, Mn, Ni)
Authors: Tuccillo Mariarosaria , Palumbo Oriele , Pavone Michele , Muñoz-García Ana Belen , Paolone Annalisa , Brutti Sergio
Published: June 2020

Transition-metal (TM) layered oxides have been attracting enormous interests in recent decades because of their excellent functional properties as positive electrode materials in lithium-ion batteries. In particular LiCoO2 (LCO), LiNiO2 (LNO) and LiMnO2 (LMO) are the structural prototypes of a large family of complex compounds with similar layered structures incorporating mixtures of transition metals. Here, we present a comparative study on the phase stability of LCO, LMO and LNO by means of first-principles calculations, considering three different lattices for all oxides, i.e., rhombohedral (hR12), monoclinic (mC8) and orthorhombic (oP8). We provide a detailed analysis—at the same level of theory—on geometry, electronic and magnetic structures for all the three systems in their competitive structural arrangements. In particular, we report the thermodynamics of formation for all ground state and metastable phases of the three compounds for the first time. The final Gibbs Energy of Formation values at 298 K from elements are: LCO(hR12) −672 ± 8 kJ mol−1; LCO(mC8) −655 ± 8 kJ mol−1; LCO(oP8) −607 ± 8 kJ mol−1; LNO(hR12) −548 ± 8 kJ mol−1; LNO(mC8) −557 ± 8 kJ mol−1; LNO(oP8) −548 ± 8 kJ mol−1; LMO(hR12) −765 ± 10 kJ mol−1; LMO(mC8) −779 ± 10 kJ mol−1; LMO(oP8) −780 ± 10 kJ mol−1. These values are of fundamental importance for the implementation of reliable multi-phase thermodynamic modelling of complex multi-TM layered oxide systems and for the understanding of thermodynamically driven structural phase degradations in real applications such as lithium-ion batteries.
Efficient Design Method for Plasmonic Filter for Tuning Spectral Selectivity
Authors: Do Yun Seon
Published: June 2020

Nano-structure-based color technologies have been reported as alternatives for conventional pigment- or dye-based color filters due to their simple design methods and durable characteristics. Since structure-based optical resonances accompany multiple resonance modes, spectral selectivity could be degraded. In this work, a simple and effective design of a plasmonic color filter that combines the plasmonic filter with one-dimensional photonic crystals. The introduced photonic crystal provides a photonic band gap, and it helps in suppressing the undesirable transmission peaks of the plasmonic color filter that originates from higher order resonance modes. Finally, the proposed design achieves high color purity. In addition, the simplicity of the design makes it both suitable for large-area fabrication and cost effective. This work is expected to provide a practical alternative to traditional color filters.
Fungal Diversity in the Mediterranean Area
Authors: Venturella Giuseppe
Published: June 2020

The Special Issue entitled “Fungal Diversity in the Mediterranean Area” aimed at highlighting the role of various organisms in the Mediterranean habitat. The role of fungi at the root and phyllosphere level; the biodiversity in small island territories and the sea; rare forms of fungi never previously found; the commercial, food, and therapeutic value of some ascomycetes and basidiomycetes; the diversity related to fungi associated with galls on plants; and the important role of culture collection for the ex situ conservation of fungal biodiversity are the topics dealt with in this Special Issue.
Microbial Communities in the Fynbos Region of South Africa: What Happens during Woody Alien Plant Invasions
Authors: Jacobs Karin , Conradie Tersia , Jacobs Shayne
Published: June 2020

The Cape Floristic Region (CFR) is globally known for its plant biodiversity, and its flora is commonly referred to as fynbos. At the same time, this area is under severe pressure from urbanization, agricultural expansion and the threat of invasive alien plants. Acacia, Eucalyptus and Pinus are the common invasive alien plants found across the biome and considerable time, effort and resources are put into the removal of invasive alien plants and the rehabilitation of native vegetation. Several studies have shown that invasion not only affects the composition of plant species, but also has a profound effect on the soil chemistry and microbial populations. Over the last few years, a number of studies have shown that the microbial populations of the CFR are unique to the area, and harbour many endemic species. The extent of the role they play in the invasion process is, however, still unclear. This review aims to provide an insight into the current knowledge on the different microbial populations from this system, and speculate what their role might be during invasion. More importantly, it places a spotlight on the lack of information about this process.
Shaft Integrated Electromagnetic Energy Harvester with Gravitational Torque
Authors: Ullrich Michel , Wolf Maik , Rudolph Mathias , Diller Wolfgang
Published: June 2020

This paper presents the development of an electromagnetic energy harvester for electrical supply of a sensor unit integrated on the rotating inner ring of a rolling bearing. This energy harvester is of special interest for condition monitoring tasks on rotating shafts. A sensory monitor on the inner ring can detect wear conditions at an early stage. The harvester works without mechanical and energetic contact to surrounding components by utilizing the rotational energy of the shaft. The functionality of the Energy Harvester is enabled by the inertia principle, which is caused by an asymmetrical mass distribution. We provide simulations to validate the designs. This work includes simulation studies on the electrical power output of the harvester. Therefore, the necessary simulation of the magnetic problems is realized in a substitute simulation environment. The harvester design enables existing machines to be equipped with the harvester to provide an energy supply on rotating shafts. This clamp connection enables shaft mounting independent of location without mechanical work on the shaft. With an electrical power of up to 163.6 m W, at 3600 rpm, the harvester is used as an energy supply, which enables sensor-based monitoring of slow wear processes.
Simple and Accurate Border Detection Algorithm for Melanoma Computer Aided Diagnosis
Authors: Guaragnella Cataldo , Rizzi Maria
Published: June 2020

The interest of the scientific community for computer aided skin lesion analysis and characterization has been increased during the last years for the growing incidence of melanoma among cancerous pathologies. The detection of melanoma in its early stage is essential for prognosis improvement and for guaranteeing a high five-year relative survival rate of patients. The clinical diagnosis of skin lesions is challenging and not trivial since it depends on human vision and physician experience and expertise. Therefore, a computer method that makes an accurate extraction of important details of skin lesion image can assist dermatologists in cancer detection. In particular, the border detection is a critical computer vision issue owing to the wide range of lesion shapes, sizes, colours and skin texture types. In this paper, an automatic and effective pigmented skin lesion segmentation method in dermoscopic image is presented. The proposed procedure is adopted to extract a mask of the lesion region without the adoption of other signal processing procedures for image improvement. A quantitative experimental evaluation has been performed on a publicly available database. The achieved results show the method validity and its high robustness towards irregular boundaries, smooth transition between lesion and skin, noise and artifact presence.
Systemic Alterations of Immune Response-Related Proteins during Glaucoma Development in the Murine Model DBA/2J
Authors: Fernández-Vega Cueto Andrés , Álvarez Lydia , García Montserrat , Artime Enol , Álvarez Barrios Ana , Rodríguez-Uña Ignacio , Coca-Prados Miguel , González-Iglesias Héctor
Published: June 2020

Animal models of glaucoma, a neurodegenerative disease affecting the retina, offer the opportunity to study candidate molecular biomarkers throughout the disease. In this work, the DBA/2J glaucomatous mouse has been used to study the systemic levels of several proteins previously identified as potential biomarkers of glaucoma, along the pre- to post-glaucomatous transition. Serum samples obtained from glaucomatous and control mice at 4, 10, and 14 months, were classified into different experimental groups according to the optic nerve damage at 14 months old. Quantifications of ten serum proteins were carried out by enzyme immunoassays. Changes in the levels of some of these proteins in the transition to glaucomatous stages were identified, highlighting the significative decrease in the concentration of complement C4a protein. Moreover, the five-protein panel consisting of complement C4a, complement factor H, ficolin-3, apolipoprotein A4, and transthyretin predicted the transition to glaucoma in 78% of cases, and to the advanced disease in 89%. Our data, although still preliminary, suggest that disease development in DBA/2J mice is associated with important molecular changes in immune response and complement system proteins and demonstrate the utility of this model in identifying, at systemic level, potential markers for the diagnosis of glaucoma.
Compact Medium Voltage DC/DC Converter Using Series-Connected Power Devices
Authors: Zheng Shaoduo , Lyu Feng
Published: June 2020

Medium voltage (MV) DC/DC converters are key equipment for interconnection between DC power lines with different voltage levels in MVDC grids. The Input-series-output-parallel (ISOP) modular MV DC/DC converter is feasible to realize MV to low voltage (LV) conversion. However, a large number of LV modules in the converter may reduce the reliability and increase the complexity. This letter proposes a phase-shifted full-bridge MV DC/DC converter using series-connected power devices as switching modules. The converter is of low cost, simple structure, compact volume, and high reliability because these switching modules require only one external isolated driver circuit and very few components to achieve voltage sharing among series-connected power devices. The operation principle of the switching modules is analyzed, and the simulation and experimental results validate the feasibility of the converter design.
Exploring Malware Behavior of Webpages Using Machine Learning Technique: An Empirical Study
Authors: Alwaghid Alhanoof , Sarkar Nurul
Published: June 2020

Malware is one of the most common security threats experienced by a user when browsing webpages. A good understanding of the features of webpages (e.g., internet protocol, port, URL, Google index, and page rank) is required to analyze and mitigate the behavior of malware in webpages. This main objective of this paper is to analyze the key features of webpages and to mitigate the behavior of malware in webpages. To this end, we conducted an empirical study to identify the features that are most vulnerable to malware attacks and its results are reported. To improve the feature selection accuracy, a machine learning technique called bagging is employed using the Weka program. To analyze these behaviors, phishing and botnet data were obtained from the University of California Irvine machine learning repository. We validate our research findings by applying honeypot infrastructure using the Modern Honeypot Network (MHN) setup in a Linode Server. As the data suffer from high variance in terms of the type of data in each row, bagging is chosen because it can classify binary classes, date classes, missing values, nominal classes, numeric classes, unary classes and empty classes. As a base classifier of bagging, random tree was applied because it can handle similar types of data such as bagging, but better than other classifiers because it is faster and more accurate. Random tree had 88.22% test accuracy with the lowest run time (0.2 sec) and a receiver operating characteristic curve of 0.946. Results show that all features in the botnet dataset are equally important to identify the malicious behavior, as all scored more than 97%, with the exception of TCP and UDP. The accuracy of phishing and botnet datasets is more than 89% on average in both cross validation and test analysis. Recommendations are made for the best practice that can assist in future malware identification.
Design and Evaluation of Cell Interaction Based Vedic Multiplier Using Quantum-Dot Cellular Automata
Authors: Safoev Nuriddin , Jeon Jun-Cheol
Published: June 2020

A multiplier is one of the main units for digital signal processing and communication systems. In this paper, a high speed and low complexity multiplier is designed on the basis of quantum-dot cellular automata (QCA), which is considered promising nanotechnology. We focus on Vedic multiplier architectures according to Vedic mathematics from ancient Indian sculptures. In fact, an adder is an important block in the design of almost all types of multipliers and a ripple carry adder is used to design simple multiplier implementations. However, a high-speed multi-bit multiplier requires high-speed adder owing to carry propagation. Cell-interaction-based QCA adders have better improvements over conventional majority-gate-based adders. Therefore, a two-bit Vedic multiplier is proposed in QCA and it is used to implement a four-bit form of the multiplier. The proposed architecture has a lower cell count and area compared to other existing structures. Moreover, simulation results demonstrate that the proposed design is sustainable and can be used to realize complex circuit designs for QCA communication networks.
Visiting the Forest with Kindergarten Children: Forest Suitability
Authors: Nastran Mojca
Published: June 2020

By providing ecosystem services, urban forests contribute significantly to the well-being of urban populations. Urban forests, along with other urban green spaces, are often the closest natural environment in the city where a child can play. The majority of pre-school children spend a large part of the day in kindergarten, which means that forest visits should have a prominent place in the kindergarten curriculum. Therefore, this study focuses on making the forest more suitable and thus more accessible for visits with children. The first goal of the research is to identify teachers’ preferences for the forest environment they visit with a group of pre-school children. The second goal is to present a forest suitability model for a visit with kindergarten children based on the teachers’ preferences. Based on the research survey conducted among the teachers in Slovenian public kindergartens, we formed and evaluated the criteria for the construction of a model of forest suitability for a visit with children. As the most important requirement for visiting a forest, the teachers note its proximity. They prefer a mature, mixed forest, with a bit of undergrowth, dead wood, and a presence of water and a meadow. Based on the identified criteria, we used the multi-criteria evaluation method in the GIS-environment in order to build a model of urban forest suitability for a visit with kindergarten groups of children in the study area of the City of Ljubljana, Slovenia. The results are useful in urban forest planning and management to ensure better forest suitability and accessibility for visits by children. Suitability maps can be used as one of the spatial foundations necessary for an integrated urban forest planning with emphasis on social functions. The model can be adapted beyond Slovenia to different spatial and social requirements and contexts.
Farmers’ Preferences for Conservation and Breeding Programs of Forestry Food Resources in Niger
Authors: Agúndez Dolores , Lawali Sitou , Mahamane Ali , Alía Ricardo , Soliño Mario
Published: June 2020

In a less-favored area such as the Sahel, promoting sustainable management, breeding, and conservation of forestry resources would result in improvements for agroforestry systems and food security. A contingent ranking exercise allowed us to estimate the preferences and the values given by the rural population to the attributes that would be comprised in a conservation program. The resulting preferred program is farmer-managed natural regeneration (FMNR) based on the species Adansonia digitata (baobab), with plantation, stone bunds, or tassa, and selected or bred seeds. The proposed actions to improve the tree density and the seed quality were highly valued by the respondents. Nevertheless, no clear differences were found between tassa and stone bunds, or FMNR and plantation. The main effects of the program, according to the surveyed population, include an increase in crop production and soil conservation, and higher income from tree products. This study allowed us to identify the program that would provide the greatest well-being for farmers, since it would allow them to simultaneously improve both the production of their crops and the production of the woody food species. It was shown that farmers were particularly willing to contribute to a program based on baobab, mainly because its products are used for food in the home and can be sold in markets. In this sense, the yield and production of the system would be improved by increasing the number of baobab trees. Farmers would contribute to this production system and would be willing to invest sustainable effort in the long term. The conservation and breeding program can be directed at conserving and propagating the genetic resources of A. digitata in an initial phase, selecting trees with good production, growth, and adaptation characteristics.
Maya of the Past, Present, and Future: Heritage, Anthropological Archaeology, and the Study of the Caste War of Yucatan
Authors: Diserens Morgan Kasey , Leventhal Richard M.
Published: June 2020

This paper examines the relationship between the past, present, and future of Maya heritage and archaeology. We trace some of the background of Maya archaeology and Maya heritage studies in order to understand the state of the field today. We examine and demonstrate how an integrated and collaborative community heritage project, based in Tihosuco, Quintana Roo, Mexico, has developed and changed over time in reaction to perceptions about heritage and identity within the local community. We also describe the many sub-programs of the Tihosuco Heritage and Community Development Project, showcasing our methods and outcomes, with the aim of presenting this as a model to be used by other anthropologists interested in collaborative heritage practice.
Annual Prevalence, Health Expenditures, and Co-Morbidities Trend of Iron Deficiency Anemia in Korea: National Health Insurance Service Data from 2002 to 2013
Authors: Park Yoo-Jin , Lim Hee-Sook , Kim Tae-Hee
Published: June 2020

Despite improvements in nutritional status, iron deficiency anemia (IDA) remains a debilitating nutritional problem worldwide. We estimate annual IDA prevalence rates by sex and age and the trends therein in Korea. We also calculate the health expenditures of IDA and its co-morbidities by analyzing claims data in the National Health Information Database from 2002 to 2013. All analyses were performed based on diagnosis codes of IDA (D50, D50.0, D50.8, and D50.9) regardless of whether IDA was the principal or a coexisting disease. Trends in IDA prevalence rates were evaluated by calculating annual percent changes (APCs) in prevalence. The health expenditures of IDA were calculated based on the direct medical costs (outpatient and hospitalization costs, pharmaceutical costs) and direct non-medical costs (travel costs). The overall IDA prevalence in both sexes increased approximately 2.3-fold from 2002 to 2013; the APC was +7.6%. In females, the prevalence of IDA was highest in aged 30–39 and 40–49 years. The APC was highest in those aged <10 years (+18.2%), followed by those aged ≥80 (+14.7%) and 70–79 (+9.8%) years. In males, the prevalence rates were highest in aged <10 years, followed by those aged ≥60 years. The APC was highest in those aged <10 years (+19.1%), followed by those aged ≥80 years (+10.5%). The total health expenditures increased 2.8-fold during 12 years. Diseases of the respiratory or gastrointestinal tract were the most prevalent co-morbidities in both males and females. The annual prevalence of IDA continues to rise in association with adverse health expenditures and co-morbidities in spite of improvements in nutritional status. Most importantly, infants and young children, the elderly, and females aged 30–49 years are at highest risk of IDA. A national, prospective, and well-organized effort to improve iron status and to manage IDA is required.
Occurrence and Health-Risk Assessment of Trace Metals in Geothermal Springs within Soutpansberg, Limpopo Province, South Africa
Authors: Durowoju Olatunde Samod , Ekosse Georges-Ivo Ekosse , Odiyo John Ogony
Published: June 2020

Geothermal springs are natural geological phenomena that occur throughout the world. South Africa is blessed with several springs of this nature. Limpopo province contains 31% of all geothermal springs in the country. The springs are classified according to the residing mountain: Soutpansberg, Waterberg and Drakensberg. This study focused on the geothermal springs within the Soutpansberg region; that is, Mphephu, Siloam, Sagole and Tshipise. The study was aimed at assessing the occurrence and potential health risk associated with drinking water from geothermal springs within Soutpansberg. Geothermal springs and boreholes were sampled for a period of 12 months (May 2017–May 2018) to accommodate two major seasons in the study areas. The physicochemical and trace metal compositions of the geothermal springs and boreholes (tepid and hot) were analyzed using ion chromatography (IC) (Dionex Model DX 500) and inductively coupled plasma-mass spectrometer (ICP-MS). Trace metal concentrations of the geothermal springs and boreholes were within permissible drinking water guidelines by the South African National Standards (SANS) and World Health Organisation (WHO), with exception of mercury (Hg), which is high in summer season. The bioaccumulation from regular consumption could, however, result in negative effects. Pearson’s correlation revealed that there is a direct relationship between temperature and pH, and some of the trace metals (V, Zn, Hg, Pb). This implies dissolution of minerals (rock-water interaction) under slightly high temperature. Multivariate statistics further elucidate the relationship and possible sources of the trace metals. Therefore, it can be inferred that the rock-water interaction is the main geochemical process governing the release of trace metals in groundwater. Hazard Index values for both children and adults were higher than 1, and this implies that the communities are at high risk of non-cancer health effects. Further, As, Cr and Cd were found to be the highest contributors to the potential cancer risk in the study areas, with children having a higher risk than adults. Therefore, there is a need for clinical/epidemiological study, and regular monitoring and control measures, to verify actual prevalence of cancer and protect human health, particularly the children, within the study areas.
Deaths in SARS-Cov-2 Positive Patients in Italy: The Influence of Underlying Health Conditions on Lethality
Authors: Deiana Giovanna , Azara Antonio , Dettori Marco , Delogu Fiorenzo , Vargiu Gavino , Gessa Isabella , Stroscio Filippo , Tidore Marcello , Steri Giorgio , Castiglia Paolo
Published: June 2020

This study aims to underline the clinical characteristics of patients who died after testing positive for SARS-CoV-2 infection in one region of Italian and to evaluate the influence of underlying health conditions on the fatal outcome. A matched case-control study was designed by analyzing the data regarding positive subjects observed up to April 21, 2020. The case fatality rate was 7.9%, with a higher proportion of deaths in men than women. The specific standardized mortality ratio was 0.15—0.13 for males and 0.2 for females, showing that mortality is much lower than expected. Cardiovascular diseases, chronic lung diseases and diabetes mellitus showed a significant association with the outcome. Although the case fatality rate in Sardinia in regard to age and gender patterns seems to be similar to that for Italy as a whole, its quantitative value was far lower than the national one and possible explanations might include the genetic characteristics of the Sardinian population or the immediate closure of its borders as soon as the epidemic started. Our results highlighted that lethality is strongly dependent on the presence of multiple concomitant serious diseases. It is important to have epidemiological strategies for effective guidance on public health actions in order to improve chances of survival.
Supporting Disaster Resilience Spatial Thinking with Serious GeoGames: Project Lily Pad
Authors: Tomaszewski Brian , Walker Amy , Gawlik Emily , Lane Casey , Williams Scott , Orieta Deborah , McDaniel Claudia , Plummer Matthew , Nair Anushka , San Jose Nicolas , Terrell Nathan , Pecsok Kyle , Thomley Emma , Mahoney Erin , Haberlack Emily , Schwartz David
Published: June 2020

The need for improvement of societal disaster resilience and response efforts was evident after the destruction caused by the 2017 Atlantic hurricane season. We present a novel conceptual framework for improving disaster resilience through the combination of serious games, geographic information systems (GIS), spatial thinking, and disaster resilience. Our framework is implemented via Project Lily Pad, a serious geogame based on our conceptual framework, serious game case studies, interviews and real-life experiences from 2017 Hurricane Harvey survivors in Dickinson, TX, and an immersive hurricane-induced flooding scenario. The game teaches a four-fold set of skills relevant to spatial thinking and disaster resilience, including reading a map, navigating an environment, coding verbal instructions, and determining best practices in a disaster situation. Results of evaluation of the four skills via Project Lily Pad through a “think aloud” study conducted by both emergency management novices and professionals revealed that the game encouraged players to think spatially, can help build awareness for disaster response scenarios, and has potential for real-life use by emergency management professionals. It can be concluded from our results that the combination of serious games, geographic information systems (GIS), spatial thinking, and disaster resilience, as implemented via Project Lily Pad and our evaluation results, demonstrated the wide range of possibilities for using serious geogames to improve disaster resilience spatial thinking and potentially save lives when disasters occur.
When Appearance Misleads: The Role of the Entomopathogen Surface in the Relationship with Its Host
Authors: Brivio Maurizio Francesco , Mastore Maristella
Published: June 2020

Currently, potentially harmful insects are controlled mainly by chemical synthetic insecticides, but environmental emergencies strongly require less invasive control techniques. The use of biological insecticides in the form of entomopathogenic organisms is undoubtedly a fundamental resource for the biological control of insect pests in the future. These infectious agents and endogenous parasites generally act by profoundly altering the host’s physiology to death, but their success is closely related to the neutralization of the target insect’s immune response. In general, entomopathogen parasites, entomopathogenic bacteria, and fungi can counteract immune processes through the effects of secretion/excretion products that interfere with and damage the cells and molecules typical of innate immunity. However, these effects are observed in the later stages of infection, whereas the risk of being recognized and neutralized occurs very early after penetration and involves the pathogen surface components and molecular architecture; therefore, their role becomes crucial, particularly in the earliest pathogenesis. In this review, we analyze the evasion/interference strategies that entomopathogens such as the bacterium Bacillus thuringiensis, fungi, nematocomplexes, and wasps implement in the initial stages of infection, i.e., the phases during which body or cell surfaces play a key role in the interaction with the host receptors responsible for the immunological discrimination between self and non-self. In this regard, these organisms demonstrate evasive abilities ascribed to their body surface and cell wall; it appears that the key process of these mechanisms is the capability to modify the surface, converting it into an immunocompatible structure, or interaction that is more or less specific to host factors.
Characterization and Modeling of Surface Roughness and Burr Formation in Slot Milling of Polycarbonate
Authors: Adeniji David , Schoop Julius , Gunawardena Shehan , Hanson Craig , Jahan Muhammad
Published: June 2020

Thermoplastic materials hold great promise for next-generation engineered and sustainable plastics and composites. However, due to their thermoplastic nature and viscoplastic material response, it is difficult to predict the properties of surfaces generated by machining. This is especially problematic in micro-channel machining, where burr formation and excessive surface roughness lead to poor component-surface integrity. This study attempts to model the influence of size effects, which occur due to the finite sharpness of any cutting tool, on surface finish and burr formation during micro-milling of an important thermoplastic material, polycarbonate. Experimental results show that the depth of cut does not affect either surface finish or burr formation. A proposed new sideflow model shows the dominant effect of cutting-edge radius and feed rate on surface finish, while tool edge roughness, coating and feed rate have the most pronounced influence on burr formation. Overall, a good agreement between the experimental data and the proposed size effect model for the machining of thermoplastic material was found. Based on these results, tool geometry and process parameters may be optimized for improved surface integrity of machined thermoplastic components.
A Novel Approach for the Detection of Geometric- and Weight-Related FSW Tool Wear Using Stripe Light Projection
Authors: Hasieber Michael , Grätzel Michael , Bergmann Jean Pierre
Published: June 2020

Friction stir welding (FSW) has become an up-and-coming joining method with a wide range of industrial applications. Besides the unique weld seam properties, recent investigations have focused on the process-related tool wear of shoulder and probe, which can have detrimental economic and technological effects. This paper presents a systematic quantitative characterization of FSW tool wear using stripe light projection as a novel method to detect weight and form deviations of shoulder and probe. The investigations were carried out with a robotic welding setup in which AA-6060 T66 sheets, with a thickness of 8 mm, were joined by weld seams up to a total length of 80 m. During the experimental tests, geometrical deviations of the tool induced by wear were detected for varying weld seam lengths and different measuring points on the probe and shoulder. It was shown that wear depended on welding length which in turn caused significant deviations and weight losses on shoulder and probe. Furthermore, it was demonstrated that the wear on shoulder and probe can be considered separately. It was found that there is a progressive wear rate on the shoulder and a degressive wear rate on the probe depending on the weld seam length. To demonstrate the negative impact of tool wear on shoulder and probe after 80 m weld seam length, visual and metallographic inspections and tensile tests were carried out to detect resultant irregularities in the weld seam.
Implementation of MALDI Mass Spectrometry Imaging in Cancer Proteomics Research: Applications and Challenges
Authors: Berghmans Eline , Boonen Kurt , Maes Evelyne , Mertens Inge , Pauwels Patrick , Baggerman Geert
Published: June 2020

Studying the proteome–the entire set of proteins in cells, tissues, organs and body fluids—is of great relevance in cancer research, as differential forms of proteins are expressed in response to specific intrinsic and extrinsic signals. Discovering protein signatures/pathways responsible for cancer transformation may lead to a better understanding of tumor biology and to a more effective diagnosis, prognosis, recurrence and response to therapy. Moreover, proteins can act as a biomarker or potential drug targets. Hence, it is of major importance to implement proteomic, particularly mass spectrometric, approaches in cancer research, to provide new crucial insights into tumor biology. Recently, mass spectrometry imaging (MSI) approaches were implemented in cancer research, to provide individual molecular characteristics of each individual tumor while retaining molecular spatial distribution, essential in the context of personalized disease management and medicine.
Mass Spectrometry: A Rosetta Stone to Learn How Fungi Interact and Talk
Authors: Calla-Quispe Erika , Fuentes-Rivera Hammerly Lino , Ramírez Pablo , Martel Carlos , Ibañez Alfredo J.
Published: June 2020

Fungi are a highly diverse group of heterotrophic organisms that play an important role in diverse ecological interactions, many of which are chemically mediated. Fungi have a very versatile metabolism, which allows them to synthesize a large number of still little-known chemical compounds, such as soluble compounds that are secreted into the medium and volatile compounds that are chemical mediators over short and long distances. Mass spectrometry (MS) is currently playing a dominant role in mycological studies, mainly due to its inherent sensitivity and rapid identification capabilities of different metabolites. Furthermore, MS has also been used as a reliable and accurate tool for fungi identification (i.e., biotyping). Here, we introduce the readers about fungal specialized metabolites, their role in ecological interactions and provide an overview on the MS-based techniques used in fungal studies. We particularly present the importance of sampling techniques, strategies to reduce false-positive identification and new MS-based analytical strategies that can be used in mycological studies, further expanding the use of MS in broader applications. Therefore, we foresee a bright future for mass spectrometry-based research in the field of mycology.
Clopidogrel, an ADP-P2Y12 Receptor Antagonist, Can Prevent Severe Postoperative Pain: A Retrospective Chart Review
Authors: Tsuchida Rikuhei , Sumitani Masahiko , Abe Hiroaki , Ando Masae , Saita Kosuke , Hattori Kohshi , Mietani Kazuhito , Inoue Reo , Uchida Kanji
Published: June 2020

The purinergic P2Y12 receptor regulates microglial activation, resulting in persistence and aggravation of pain in neuropathic and nociceptive pain models. We conducted a retrospective chart review to explore the analgesic potency of the P2Y12 receptor-specific antagonist, clopidogrel, for clinical management of postoperative pain in patients who underwent abdominal surgery. Twenty-seven patients with cardiovascular comorbidities, who underwent laparoscopic abdominal surgery and had ceased aspirin (ASP, n = 17) or clopidogrel (CLP, n = 10) for 14 days pre-operatively, were enrolled retrospectively. In both groups, the number of opioids and non-steroidal anti-inflammatory drugs (NSAIDs) consumed for managing postoperative pain was compared using the chi-square test and Mann–Whitney test. Our results showed that from postoperative day (POD) 0 to POD 3, the average numerical rating reflecting the postoperative pain was comparable between the two groups (CLP: 4.0 ± 1.4 vs. ASP: 3.7 ± 0.8, P-value = 0.56). However, at POD 7, opioid consumption in the CLP-treated group (fentanyl-equivalent dose: 0.49 ± 0.56 mg) was significantly lower than that in the ASP-treated group (1.48 ± 1.35 mg, P-value = 0.037). After reaching a stable state by repeated systemic administration, clopidogrel sustained the analgesic efficacy for a certain period. In conclusion, microglial P2Y12 receptors may mediate signal transduction of postoperative nociceptive pain and enhance clinical opioid analgesia.
Assessment of the Performance of Electrodialysis in the Removal of the Most Potent Odor-Active Compounds of Herring Milt Hydrolysate: Focus on Ion-Exchange Membrane Fouling and Water Dissociation as Limiting Process Conditions
Authors: Todeschini Sarah , Perreault Véronique , Goulet Charles , Bouchard Mélanie , Dubé Pascal , Boutin Yvan , Bazinet Laurent
Published: June 2020

Herring milt hydrolysate (HMH), like many fish products, presents the drawback to be associated with off-flavors. As odor is an important criterion, an effective deodorization method targeting the volatile compounds responsible for off-flavors needs to be developed. The potential of electrodialysis (ED) to remove the 15 volatile compounds identified, in the first part of this work, for their main contribution to the odor of HMH, as well as trimethylamine, dimethylamine and trimethylamine oxide, was assessed by testing the impact of both hydrolysate pH (4 and 7) and current conditions (no current vs. current applied). The ED performance was compared with that of a deaerator by assessing three hydrolysate pH values (4, 7 and 10). The initial pH of HMH had a huge impact on the targeted compounds, while ED had no effect. The fouling formation, resulting from electrostatic and hydrophobic interactions between HMH constituents and ion-exchange membranes (IEM); the occurrence of water dissociation on IEM interfaces, due to the reaching of the limiting current density; and the presence of water dissociation catalyzers were considered as the major limiting process conditions. The deaerator treatment on hydrolysate at pH 7 and its alkalization until pH 10 led to the best removal of odorant compounds.
Corrosion Resistance and Ion Release of Dental Prosthesis of CoCr Obtained by CAD-CAM Milling, Casting and Laser Sintering
Authors: Padrós Roberto , Giner-Tarrida Luís , Herrero-Climent Mariano , Punset Miquel , Gil Francisco Javier
Published: June 2020

Corrosion resistance and ion release behavior have been evaluated for thirty dental restoration samples obtained by three different manufacturing systems: computer-aided design and manufacturing (CAD-CAM), traditional casting and laser sintering. The alloy used was the CoCr alloy (same batch) generally used in clinical dentistry. Corrosion resistance has been evaluated by electrochemical testing in an artificial saliva medium at 37 °C. Corrosion parameters such as critical current density (icr), corrosion potential (Ecorr), and passive current density (ip), have been determined. Cobalt and Chromium ions released from the different samples have also been analyzed in an artificial saliva medium at 37 °C by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) at different immersion times. The casted samples showed higher corrosion rates and ion-release levels. The CAD-CAM milled samples presented lower ion-release levels and better corrosion resistance due to the total solubility of the chemical elements in only one phase with the same chemical composition. This homogeneity avoids the formation of electrochemical corrosion. Moreover, the absence of defects and residual stresses increases the corrosion resistance. Casted and laser sintered prostheses have shown the presence of Cr, W, and Nb rich-precipitates which are detrimental to the corrosion resistance. These precipitates produce a decrease in the Cr content on the surface. It is well known that the corrosion resistance increases with the Cr content by the formation of Chromium oxide on the surface that increases passivation. Consequently, the decrease in Cr induces an increase in corrosion and ion release.
Editorial of Special Issue “Nanostructured Light-Emitters”
Authors: Nguyen Hieu P. T.
Published: June 2020

Significant progress has been made in the development of nanophotonic devices and the use of nanostructured materials for optoelectronic devices, including light-emitting diodes (LEDs) and laser diodes, has recently attracted tremendous attention due to the fact of their unique geometry [...]
Editorial for the Special Issue on Particles Separation in Microfluidic Devices
Authors: Tottori Naotomo , Nisisako Takasi
Published: June 2020

The separation and sorting of micro- and nano-sized particles is an important step in chemical, biological, and medical analyses [...]
Recovery of Co, Li, and Ni from Spent Li-Ion Batteries by the Inorganic and/or Organic Reducer Assisted Leaching Method
Authors: Urbańska Weronika
Published: June 2020

The battery powder (anodic and cathodic mass) manually separated from spent Li-ion batteries used in laptops was subjected to acidic reductive leaching to recover the Co, Li, and Ni contained in it. In the laboratory experiments, 1.5 M sulfuric acid was used as the leaching agent and the reducing agents were 30% H2O2 solution or/and glutaric acid. Glutaric acid is a potential new reducing agent in the leaching process of spent lithium-ion batteries (LIBs). The influence of the type of the used reducer on obtained recovery degrees of Co, Li, and Ni as well as the synergism of the two tested reducing compounds were analyzed. As a result, it was determined that it is possible to efficiently hydrometallurgically separate Co, Li, and Ni from battery powder into solutions. The highest recovery degrees of the investigated metals (Co: 87.85%; Li: 99.91%; Ni: 91.46%) were obtained for samples where two reducers, perhydrol and glutaric acid, were added, thus confirming the assumed synergic action of H2O2 and C5H8O4 in a given reaction environment.
Separation of Aluminum and Iron from Lanthanum—A Comparative Study of Solvent Extraction and Hydrolysis-Precipitation
Authors: Balinski Adam , Kelly Norman , Helbig Toni , Meskers Christina , Reuter Markus Andreas
Published: June 2020

This study investigates the removal of aluminum and iron from rare earth element (REE) containing solutions by solvent extraction with saponified naphthenic acid and by hydrolysis-precipitation. The results emphasize both, the preferential application as well as limitations of every method. We find that emulsification occurring during the solvent extraction of aluminum is caused by its slow extraction rate in comparison to the neutralization reaction and by the proximity of the pH value required for aluminum extraction and the pH value at which hydrolysis of aluminum occurs. However, by choosing a long shaking time of at least 4 h, the emulsion recedes. The formation of emulsion can be avoided by strict control of pH value during the extraction. Moreover, the loading capacity of the organic phase with aluminum is limited due to the strong increase in viscosity of the organic phase with increasing aluminum concentration and due to the gel formation. Regarding the extraction of iron, the amount of extracted ions is limited due to the overlap of the pH range required for the extraction with pH range in which sparingly soluble iron oxides/hydroxides are formed. In summary, aluminum and iron can be simultaneously removed from REE-sulfate solution by solvent extraction with saponified naphthenic acid in one extraction stage only from diluted solutions. However, in comparison to the hydrolysis-precipitation method, a higher purity of the solution is achieved. A complete removal of aluminum and iron from concentrated solutions can be achieved in two stages. First, the content of aluminum and iron should be reduced by hydrolysis-precipitation. After that, a high-purity solution can be obtained by subsequent solvent extraction by saponified naphthenic acid.
Geochemical Signature and Magnetic Fabric of Capinha Massif (Fundão, Central Portugal): Genesis, Emplacement and Relation with W–Sn Mineralizations
Authors: Gonçalves Ana , Sant’Ovaia Helena , Noronha Fernando
Published: June 2020

The Fundão–Serra da Estrela–Capinha (FSEC) region is characterized by peraluminous to metaluminous Variscan granites intrusive in a complex and thick metasedimentary sequence. This work seeks to characterize the Capinha granite (CG), understand its spatial and genetic relationship with the host Peroviseu–Seia (PS), Belmonte–Covilhã (BC) and Fáguas granites, and evaluate its metallogenic potential. To achieve these goals, a multidisciplinary approach was undertaken, including field work and identification of the petrography and microstructures, whole rock geochemistry and anisotropy of magnetic susceptibility. Four distinct and independent differentiation trends were identified in the granites, namely, PS, BC, Fráguas and CG. The PS and BC played a role as host rocks for the W and Sn mineralizations. The Fráguas granite is anomalous in Sn and spatially related to the Sn–Li mineralizations, while the CG is anomalous in W and spatially related to W–Sn mineralizations. The post-tectonic CG is a peraluminous ilmenite-type whose ascent and emplacement were tectonically controlled. The Capinha magma used the intersection between the 25° N and 155° N strike–slip crustal scale faults for passive ascent and emplacement during the late-Variscan extensional phases. The magnetic fabric was drawn using an asymmetric tongue-shaped laccolith for CG. CG experienced two brittle deformation stages that marked the maximum compressive rotation from NE–SW to NNW–SSE.
Experimental Development of a Novel Mine Backfill Material: Foam Mine Fill
Authors: Hefni Mohammed , Hassani Ferri
Published: June 2020

This study aims to develop a novel mine backfill material called foam mine fill (FMF). A cellular structure is achieved by incorporating a premade foam into the backfill mixture using an air-entraining agent. FMF samples were prepared with copper-nickel mine tailings and normal Portland cement. Experiments were designed to investigate the effect of binder dosage, volume of entrained air, and foam mixing time on FMF unconfined compressive strength (UCS) and dry density. Moreover, a qualitative microscopic assessment investigated the effect of foam mixing time on air bubble structure. The pore size distribution and porosity of selected samples were investigated through mercury intrusion porosimetry. Relative to reference samples without entrained air, the UCS of FMF samples was 20–50% lower. However, the concomitant lower dry density (by up to 360 kg/m3) could enhance the safety of the underground working environment, especially in underhand cut-and-fill mining where miners and machinery work beneath the backfilled stope, and lower-density fill material would minimize the adverse effects of potential backfill failure. Prolonged foam mixing time led to a significant loss in UCS and total collapse of the air bubble structure. Other potential applications for FMF are areas where there are tailings shortages and as an alternative to hydraulic fill.