bluuebunny/crossref_metadata_2025 huggingface dataset:
Drivers of Spruce Bark Beetle (Ips typographus) Infestations on Downed Trees after Severe Windthrow
Authors: Hroššo Branislav , Mezei Pavel , Potterf Mária , Majdák Andrej , Blaženec Miroslav , Korolyova Nataliya , Jakuš Rastislav
Published: November 2020

Research Highlights: Bark beetles are important agents of disturbance regimes in temperate forests, and specifically in a connected wind-bark beetle disturbance system. Large-scale windthrows trigger population growth of the European spruce bark beetle (Ips typographus L.) from endemic to epidemic levels, thereby allowing the killing of Norway spruce trees over several consecutive years. Background and Objectives: There is a lack of evidence to differentiate how outbreaks are promoted by the effects of environmental variables versus beetle preferences of trees from endemic to outbreak. However, little is known about how individual downed-tree characteristics and local conditions such as tree orientation and solar radiation affect beetle colonization of downed trees. Materials and Methods: To answer this question, we investigated the infestation rates and determined tree death categories (uprooted, broken, and stump) in wind-damaged areas in Western Tatra Mts. in Carpathians (Slovakia) from 2014–2016, following a windthrow in May 2014. In total, we investigated 225 trees over eight transects. For every tree, we measured its morphological (tree height, crown characteristics), environmental (solar radiation, terrain conditions, trunk zenith), temporal (time since wind damage), and beetle infestation (presence, location of attack, bark desiccation) parameters. We applied Generalized Additive Mixed Models (GAMM) to unravel the main drivers of I. typographus infestations. Results: Over the first year, beetles preferred to attack broken trees and sun-exposed trunk sides over uprooted trees; the infestation on shaded sides started in the second year along with the infestation of uprooted trees with lower desiccation rates. We found that time since wind damage, stem length, and incident solar radiation increased the probability of beetle infestation, although both solar radiation and trunk zenith exhibited nonlinear variability. Our novel variable trunk zenith appeared to be an important predictor of bark beetle infestation probability. We conclude that trunk zenith as a simple measure defining the position of downed trees over the terrain can anticipate beetle infestation. Conclusions: Our findings contribute to understanding of the bark beetle’s preferences to colonize windthrown trees in the initial years after the primary wind damage. Further, our findings can help to identify trees that are most susceptible to beetle infestation and to prioritize management actions to control beetle population while maintaining biodiversity.
Multispecies Fresh Water Algae Production for Fish Farming Using Rabbit Manure
Authors: Richard Adandé , Nourou Dine Liady Mouhamadou , Gildas Djidohokpin , Dogbè Clément Adjahouinou , Tobias Césaire Azon Mahuan , Jean-Claude Micha , Didier Emile Fiogbe
Published: November 2020

The current study aims at determining the optimal usage conditions of rabbit manure in a multispecies fresh water algae production for fish farming. This purpose, the experimental design is made of six treatments in triplicate including one control T0, T1, T2, T3, T4, T5 corresponding respectively to 0, 300, 600, 900, 1200, 1500 g/m3 of dry rabbit manure put into buckets containing 40 L of demineralized water and then fertilized. The initial average seeding density is made of 4 × 103 ± 2.5 × 102 cells/L of Chlorophyceae, 1.5 × 103 ± 1 × 102 cells/L of Coscinodiscophyceae, 3 × 103 ± 1.2 × 102 cells/L of Conjugatophyceae, 2.8 × 103 ± 1.5 × 102 cells/L of Bascillariophyceae, and 2.5 × 103 ± 1.4 × 102 cells/L of Euglenophyceae. During the experiments, the effects of these treatments on abiotic and biotic parameters (chlorophyll-a concentration, phytoplankton density and algal density) of different production media were monitored. Results show that average density of different phytoplankton classes is higher in treatment T5 (7.91 × 108 ± 6.78 × 107 cells/L) followed by T4 (5.56 × 108 ± 4.27 × 107 cells/L), T2 (3.87 × 108 ± 3.10 × 108 cells/L), T3 (3.79 × 108 ± 3.18 × 108 cells/L, with high significant difference (F (4,84) = 5, 35, p < 0.00). Chl-a concentration varied from 0.07 ± 0.05 mg/L (T0) to 14.47 ± 12.50 mg/L (T5) with high significant differences observed among treatments (F (5,83) = 3,09, p = 0,01). In addition, fourteen (14) species belonging to eight (8) families, five (5) classes and three (3) phyla were identified in our different production media. During the culture, Chlorophyceae class was the most represented in all treatments with 5 species (36% of the specific diversity) while Euglenophyceae class (7%) was the least represented with only one (01) species. According to these results, treatments T2 (600 g/m3), T3 (900 g/m3) and T4 (1200 g/m3) of dry rabbit manure are those worthy to be recommended as an alternative for a low cost massive production of multispecies freshwater algae that can be easily used by freshwater zooplankton and macroinvertebrates. Indeed, despite the best performances that it shows, treatment T5, presents important eutrophication’s risks.
Validations of the Microchannel Flow Model for Characterizing Vascularized Tissues
Authors: Poul Sedigheh S. , Ormachea Juvenal , Hollenbach Stefanie J. , Parker Kevin J.
Published: November 2020

The microchannel flow model postulates that stress-strain behavior in soft tissues is influenced by the time constants of fluid-filled vessels related to Poiseuille’s law. A consequence of this framework is that changes in fluid viscosity and changes in vessel diameter (through vasoconstriction) have a measurable effect on tissue stiffness. These influences are examined through the theory of the microchannel flow model. Then, the effects of viscosity and vasoconstriction are demonstrated in gelatin phantoms and in perfused tissues, respectively. We find good agreement between theory and experiments using both a simple model made from gelatin and from living, perfused, placental tissue in vitro.
GOTRIPLE: A User-Centric Process to Develop a Discovery Platform
Authors: Dumouchel Suzanne , Blotière Emilie , Breitfuss Gert , Chen Yin , Donato Francesca Di , Eskevich Maria , Forbes Paula , Georgiadis Haris , Gingold Arnaud , Gorgaini Elisa , Moranville Yoann , Pohle Stefanie , Paoli Stefano de , Petitfils Clara , Toth-Czifra Erzsebet
Published: November 2020

Social sciences and humanities (SSH) research is divided across a wide array of disciplines, sub-disciplines and languages. While this specialization makes it possible to investigate the extensive variety of SSH topics, it also leads to a fragmentation that prevents SSH research from reaching its full potential. The TRIPLE project brings answers to these issues by developing an innovative discovery platform for SSH data, researchers’ projects and profiles. Having started in October 2019, the project has already three main achievements that are presented in this paper: (1) the definition of main features of the GOTRIPLE platform; (2) its interoperability; (3) its multilingual, multicultural and interdisciplinary vocation. These results have been achieved thanks to different methodologies such as a co-design process, market analysis and benchmarking, monitoring and co-building. These preliminary results highlight the need for respecting diversity of practices and communities through coordination and harmonization.
Silencing the Myosin Regulatory Light Chain Gene sqh Reduces Cold Hardiness in Ophraella communa LeSage (Coleoptera: Chrysomelidae)
Authors: Tian Zhenqi , Zhang Yan , Ma Chao , Chen Hongsong , Guo Jianying , Zhou Zhongshi
Published: November 2020

Ambrosia artemisiifolia is a noxious invasive alien weed, that is harmful to the environment and human health. Ophraella communa is a biocontrol agent for A. artemisiifolia, that was accidentally introduced to the Chinese mainland and has now spread throughout southern China. Recently, we found that upon artificial introduction, O. communa can survive in northern China as well. Therefore, it is necessary to study the cold hardiness of O. communa. Many genes have been identified to play a role in cold-tolerance regulation in insects, but the function of the gene encoding non-muscle myosin regulatory light chain (MRLC-sqh) remains unknown. To evaluate the role played by MRLC-sqh in the cold-tolerance response, we cloned and characterized MRLC-sqh from O. communa. Quantitative real-time PCR revealed that MRLC-sqh was expressed at high levels in the gut and pupae of O. communa. The expression of MRLC-sqh was shown to decrease after cold shock between 10 and 0 °C and ascend between 0 and −10 °C, but these did not show a positive association between MRLC-sqh expression and cold stress. Silencing of MRLC-sqh using dsMRLC-sqh increased the chill-coma recovery time of these beetles, suggesting that cold hardiness was reduced in its absence. These results suggest that the cold hardiness of O. communa may be partly regulated by MRLC-sqh. Our findings highlight the importance of motor proteins in mediating the cold response in insects.
Effect of Pheromones, Plant Volatiles and Spinosad on Mating, Male Attraction and Burrowing of Cadra cautella (Walk.) (Lepidoptera: Pyralidae)
Authors: Sammani Abeysinghe M. P. , Dissanayaka Dissanayaka M. S. K. , Wijayaratne Leanage K. W. , Bamunuarachchige Thushara C. , Morrison William R.
Published: November 2020

Mating disruption of Cadra cautella (Walk.) (Lepidoptera: Pyralidae) using its sex pheromone components, (Z, E)-9,12-tetradecadienyl acetate (ZETA) and (Z)-9-tetradecadien-1-yl acetate (ZTA), is successful in its population management. In addition, botanical oils have extensively been investigated in stored product pest management, but the effect of synthetic sex pheromones on the mating of C. cautella in the presence of plant volatiles is still unknown. Spinosad is used in food facilities as a contact insecticide but, if C. cautella larvae burrow into food, they may escape from spinosad. Importantly, the impact of spinosad on burrowing ability of C. cautella remains unknown. Therefore, the objectives of this study were to determine the effects of sex pheromone components ZETA and ZTA in the presence of botanical oils on the mating of C. cautella and the burrowing ability of C. cautella larvae in different types of flour treated with spinosad. In the first study, male and female moths were introduced into the cubicle having botanical oils and pheromone components. The mating status of female moths and male moth attraction to the trap was determined. The control experiments had only the botanical oils or pheromones. In the second study, burrowing ability of C. cautella larvae through different flour types was evaluated over 10 d. The flour was sprayed with spinosad (treatments) or water (controls). The mating success was higher with botanical oils alone but declined with exposure to pheromone either alone or combined with botanical oils. No differences in male attraction to traps were observed in botanical only, pheromone only or pheromone + botanical oil treatments. The burrowing of C. cautella larvae differed with flour type and spinosad altered burrowing ability. Thus, we conclude that the mating and burrowing of C. cautella is influenced by its pheromone and by exposure to botanicals and spinosad.
Population Dynamics of Whiteflies and Associated Viruses in South America: Research Progress and Perspectives
Authors: Krause-Sakate Renate , Watanabe Luís Fernando Maranho , Gorayeb Eduardo Silva , da Silva Felipe Barreto , Alvarez Daniel de Lima , Bello Vinicius Henrique , Nogueira Angélica Maria , de Marchi Bruno Rossitto , Vicentin Eduardo , Ribeiro-Junior Marcos Roberto , Marubayashi Julio Massaharu , Rojas-Bertini Claudia Andrea , Muller Cristiane , Bueno Regiane Cristina Oliveira de Freitas , Rosales Marlene , Ghanim Murad , Pavan Marcelo Agenor
Published: November 2020

By having an extensive territory and suitable climate conditions, South America is one of the most important agricultural regions in the world, providing different kinds of vegetable products to different regions of the world. However, such favorable conditions for plant production also allow the development of several pests, increasing production costs. Among them, whiteflies (Hemiptera: Aleyrodidae) stand out for their potential for infesting several crops and for being resistant to insecticides, having high rates of reproduction and dispersal, besides their efficient activity as virus vectors. Currently, the most important species occurring in South America are Bemisia afer, Trialeurodes vaporariorum, and the cryptic species Middle East-Asia Minor 1, Mediterranean, and New World, from Bemisia tabaci complex. In this review, a series of studies performed in South America were compiled in an attempt to unify the advances that have been developed in whitefly management in this continent. At first, a background of the current whitefly distribution in South American countries as well as factors affecting them are shown, followed by a background of the whitefly transmitted viruses in South America, addressing their location and association with whiteflies in each country. Afterwards, a series of management strategies are proposed to be implemented in South American fields, including cultural practices and biological and chemical control, finalizing with a section containing future perspectives and directions for further research.
A Review on Scaling Mobile Sensing Platforms for Human Activity Recognition: Challenges and Recommendations for Future Research
Authors: Carvalho Liliana I. , Sofia Rute C.
Published: November 2020

Mobile sensing has been gaining ground due to the increasing capabilities of mobile and personal devices that are carried around by citizens, giving access to a large variety of data and services based on the way humans interact. Mobile sensing brings several advantages in terms of the richness of available data, particularly for human activity recognition. Nevertheless, the infrastructure required to support large-scale mobile sensing requires an interoperable design, which is still hard to achieve today. This review paper contributes to raising awareness of challenges faced today by mobile sensing platforms that perform learning and behavior inference with respect to human routines: how current solutions perform activity recognition, which classification models they consider, and which types of behavior inferences can be seamlessly provided. The paper provides a set of guidelines that contribute to a better functional design of mobile sensing infrastructures, keeping scalability as well as interoperability in mind.
Adiposity is Associated with Decreased Serum 17-Hydroxyprogesterone Levels in Non-Diabetic Obese Men Aged 18–49: A Cross-Sectional Study
Authors: Martínez-Montoro José Ignacio , Molina-Vega María , Asenjo-Plaza Maite , García-Ruiz María Concepción , Varea-Marineto Enrique , Plaza-Andrade Isaac , Álvarez-Millán Juan J. , Cabezas-Sánchez Pablo , Tinahones Francisco J. , Fernández-García José Carlos
Published: November 2020

Obesity is associated with decreased circulating testosterone levels, the main male sex hormone. However, there are a number of different male sex hormones whose dynamics remain poorly understood regarding this pathology. In this regard, 17 hydroxyprogesterone (17-OH progesterone), as an important precursor of testosterone synthetized in testes and adrenal glands, could play an essential role in testosterone deficiency in male obesity. Moreover, similarly to testosterone, 17-OH progesterone could be closely associated with visceral fat distribution and metabolic dysfunction. Thus, the aim of this study was to assess serum 17-OH progesterone levels in non-diabetic obese young men and to evaluate their relationship with clinical, analytical, and anthropometric parameters. We conducted a cross-sectional study including 266 non-diabetic men with obesity (BMI ≥ 30 kg/m2) aged 18–49 years; 17-OH progesterone and total testosterone (TT) were determined by high-performance liquid chromatography mass spectrometry. 17-OH progesterone levels were significantly lower in tertile 3 of body fat percentage in comparison with tertile 1 (0.74 ng/mL vs. 0.94 ng/mL, p < 0.01; Bonferroni correction) and in comparison with tertile 2 (0.74 ng/mL vs. 0.89 ng/mL, p = 0.02; Bonferroni correction). 17-OH progesterone levels correlated negatively with weight, BMI, waist circumference, insulin, homeostatic model assessment of insulin resistance (HOMA-IR), and visceral fat, and positively with TT, free testosterone (FT), luteinizing hormone, and fat-free mass percentage. Multivariate linear-regression analysis showed that body fat percentage and HOMA-IR were inversely associated with 17-OH progesterone levels, while FT and ACTH were positively linked to circulating 17-OH progesterone levels. In conclusion, in a population of non-diabetic obese young men, 17-OH progesterone levels were inversely associated with adiposity. Body fat percentage and insulin resistance were negatively related to 17-OH progesterone levels, whereas FT and ACTH levels were positively associated with 17-OH progesterone levels.
Improving Geometric Accuracy of 3D Printed Parts Using 3D Metrology Feedback and Mesh Morphing
Authors: Jadayel Moustapha , Khameneifar Farbod
Published: November 2020

Additive manufacturing (AM), also known as 3D printing, has gained significant interest due to the freedom it offers in creating complex-shaped and highly customized parts with little lead time. However, a current challenge of AM is the lack of geometric accuracy of fabricated parts. To improve the geometric accuracy of 3D printed parts, this paper presents a three-dimensional geometric compensation method that allows for eliminating systematic deviations by morphing the original surface mesh model of the part by the inverse of the systematic deviations. These systematic deviations are measured by 3D scanning multiple sacrificial printed parts and computing an average deviation vector field throughout the model. We demonstrate the necessity to filter out the random deviations from the measurement data used for compensation. Case studies demonstrate that printing the compensated mesh model based on the average deviation of five sacrificial parts produces a part with deviations about three times smaller than measured on the uncompensated parts. The deviation values of this compensated part based on the average deviation vector field are less than half of the deviation values of the compensated part based on only one sacrificial part.
Plasmodium falciparum Genetic Diversity in Panamá Based on glurp, msp-1 and msp-2 Genes: Implications for Malaria Elimination in Mesoamerica
Authors: Santamaría Ana María , Vásquez Vanessa , Rigg Chystrie , Moreno Dianik , Romero Luis , Justo Carlos , Chaves Luis Fernando , Saldaña Azael , Calzada José E.
Published: November 2020

Panamá, together with all the nations in Mesoamerica, has committed to eliminate malaria from the region by 2020. As these countries approach malaria elimination and local transmission decreases, an active molecular surveillance to identify genotypes circulating along the border areas is particularly needed to accurately infer infection origin, drug resistance and disease propagation patterns in the region. This study evaluated the genetic diversity and allele frequencies of msp-1, msp-2 and glurp genes using different molecular analyses (nested PCR, PCR-restriction fragment length polymorphism (RFLP) and sequencing) from 106 autochthonous and imported P. falciparum isolates collected from different endemic areas in Panamá between 2003 and 2019. We also explored if P. falciparum genotypes assessed with these molecular markers were associated with relevant malaria epidemiological parameters using a multiple correspondence analysis. A strong association of certain local haplotypes with their geographic distribution in endemic areas, but also with parasite load and presence of gametocytes, was evidenced. Few multiclonal infections and low genetic diversity among locally transmitted P. falciparum samples were detected, consequent with the low transmission intensity of this parasite in Panamá, a pattern likely to be extended across Mesoamerica. In addition, several imported cases were genetically dissimilar to local infections and representative of more diverse extra-continental lineages.
Roles, Characteristics, and Analysis of Intrinsically Disordered Proteins: A Minireview
Authors: Lermyte Frederik
Published: November 2020

In recent years, there has been a growing understanding that a significant fraction of the eukaryotic proteome is intrinsically disordered, and that these conformationally dynamic proteins play a myriad of vital biological roles in both normal and pathological states. In this review, selected examples of intrinsically disordered proteins are highlighted, with particular attention for a few which are relevant in neurological disorders and in viral infection. Next, the underlying causes for intrinsic disorder are discussed, along with computational methods used to predict whether a given amino acid sequence is likely to adopt a folded or unfolded state in solution. Finally, biophysical methods for the analysis of intrinsically disordered proteins will be discussed, as well as the unique challenges they pose in this context due to their highly dynamic nature.
Editorial: Special Issue “Molecules from Side Reactions”
Authors: D’Errico Stefano
Published: November 2020

Organic synthesis is a powerful tool that allows researchers to express their scientific creativity [...]
Effect of Jute Fibres on the Process of MICP and Properties of Biocemented Sand
Authors: Spencer Christine , van Paassen Leon , Sass Henrik
Published: November 2020

There has been increasing interest, in the past decade, in bio-mediated approaches to soil improvement for geotechnical applications. Microbially induced calcium carbonate precipitation (MICP) has been investigated as a potentially sustainable method for the strengthening and stabilisation of soil structures. This paper presents the results of a study on the effect of jute fibres on both the MICP process and properties of biocemented sand. Ureolytic Sporosarcina pasteurii has been used to produce biocemented soil columns via MICP in the laboratory. Results showed that columns containing 0.75% (by weight of sand) untreated jute fibres had unconfined compressive strengths approximately six times greater on average compared to biocemented sand columns without jute fibres. Furthermore, efficiency of chemical conversion was found to be higher in columns containing jute fibres, as measured using ion chromatography. Columns containing jute had calcimeter measured CaCO3 contents at least three times those containing sand only. The results showed that incorporation of jute fibres into the biocemented sand material had a beneficial effect, resulting in stimulation of bacterial activity, thus sustaining the MICP process during the twelve-day treatment process. This study also explores the potential of jute fibres in self-healing MICP systems.
Novel H-Bonded Synthons in Copper Supramolecular Frameworks with Aminoethylpiperazine-Based Ligands. Synthesis, Structure and Catalytic Activity
Authors: Nesterova Oksana V. , Pombeiro Armando J. L. , Nesterov Dmytro S.
Published: November 2020

New Schiff base complexes [Cu2(HL1)(L1)(N3)3]∙2H2O (1) and [Cu2L2(N3)2]∙H2O (2) were synthesized. The crystal structures of 1 and 2 were determined by single-crystal X-ray diffraction analysis. The HL1 ligand results from the condensation of salicylaldehyde and 1-(2-aminoethyl)piperazine, while a new organic ligand, H2L2, was formed by the dimerization of HL1 via a coupling of two piperazine rings of HL1 on a carbon atom coming from DMF solvent. The dinuclear building units in 1 and 2 are linked into complex supramolecular networks through hydrogen and coordination bondings, resulting in 2D and 1D architectures, respectively. Single-point and broken-symmetry DFT calculations disclosed negligible singlet–triplet splittings within the dinuclear copper fragments in 1 and 2. Catalytic studies showed a remarkable activity of 1 and 2 towards cyclohexane oxidation with H2O2 in the presence of nitric acid and pyridine as promoters and under mild conditions (yield of products up to 21%). Coordination compound 1 also acts as an active catalyst in the intermolecular coupling of cyclohexane with benzamide using di-tert-butyl peroxide (tBuOOtBu) as a terminal oxidant. Conversion of benzamide at 55% was observed after 24 h reaction time. By-product patterns and plausible reaction mechanisms are discussed.
Effect of Surface Ultrasonic Rolling Treatment on Rolling Contact Fatigue Life of D2 Wheel Steel
Authors: Liu Pengtao , Lin Zilong , Liu Chunpeng , Zhao Xiujuan , Ren Ruiming
Published: November 2020

A GPM-30 fatigue machine was used to investigate the influence of surface ultrasonic rolling (SURT) on the rolling contact fatigue (RCF) life of D2 wheel steel. The experimental results present that the RCF life of the grinding processing sample is 4.1 × 105 cycles. During the RCF process, the flaking of the fine grain layer and high surface roughness of the grinding processing sample cause the production of RCF cracks. When the samples are treated by SURT with 0.2 MPa and 0.4 MPa, the RCF life is 9.2 × 105 cycles and 9.6 × 105 cycles, respectively. After SURT, the surface roughness of the samples is reduced, and a certain thickness of gradient-plastic-deformation layer and a residual-compressive-stress layer are produced. These factors lead to the improvement of the RCF property. However, when the static pressure increases to 0.6 MPa during SURT, the RCF life of the sample is reduced during RCF testing. The micro-cracks, which are formed during SURT, become the crack source and cause the formation of RCF cracks, decreasing of the RCF life.
Reinforcement of Aluminium-Matrix Composites with Glass Fibre by Metallurgical Synthesis
Authors: Zasadzińska Małgorzata , Strzępek Paweł , Mamala Andrzej , Noga Piotr
Published: November 2020

Continuous pressure put on researchers all over the world these days to design materials of improved properties create opportunities to study new methods of production in conjunction with entirely new and innovative materials such as alloys or composites. The authors in the current research manufactured aluminium reinforced with glass fibre (GF) using metallurgical synthesis, which is an unconventional and not sufficiently studied method of production. The composites with 1, 2 and 5 wt.% of glass fibre were produced with additional material obtained using consolidation of aluminium powder in extrusion process as reference material with 5 wt.% of glass fibre. All the materials were subjected to series of tests in order to determine their microstructure, density, electrical properties, hardness and susceptibility to plastic working in the compression test. It was found that glass fibre during metallurgical synthesis of aluminium composite partially melted and thus did not reinforce the material as well as during extrusion, which has been observed not only in the scanning electron microscope (SEM) and energy-dispersive X-ray (EDX) analysis but also in the analysis of macroscopic physical and mechanical properties. Based on the analysed samples, it may be stated that electrical conductivity of the samples obtained via metallurgical synthesis is higher than might be estimated on the basis of the rule of mixtures and glass fibre content and concerning the sample with 5 wt.% of GF is higher (32.1 MS/m) than of the reference material obtained in extrusion process (30.6 MS/m). Similar situation has been observed in terms of hardness of the tested samples where a minor increase in hardness was noticeable as the amount of glass fibre increased in the composites obtained by metallurgical synthesis. It is believed to be related to the melting of glass fibre, which reduced the volume fraction of GF containing mainly silicon oxides and their diffusion into the aluminium matrix, thus causing solid solution strengthening.
Temperature-Dependent Raman Spectroscopic Study of the Double Molybdate KBi(MoO4)2
Authors: Wang Min , Wang Changhao , Wang Jian , Lu Liming , Gong Xiaoye , Tang Xiaohui , Zhang Fu , You Jinglin
Published: November 2020

In situ high-temperature Raman spectra of polycrystalline KBi(MoO4)2 were recorded from room temperature to 1073 K. Thermal stability of the monoclinic KBi(MoO4)2 was examined by temperature-dependent XRD. The monoclinic phase transformed into the scheelite tetragonal structure at 833 K, and then to the monoclinic phase at 773 K. Quantum chemistry ab initio calculation was performed to simulate the Raman spectra of the structure of KBi(MoO4)2 high-temperature melt. The experimental Raman band at 1023 K was deconvoluted into seven Gaussian peaks, and the calculated results were in good agreement with the experimental data. Therefore, the vibrational modes of Raman peaks of molten KBi(MoO4)2 were assigned. It was confirmed that the isolated structure of [Bi(MoO4)2]− monomer, consisting of Mo6+ centers and Bi3+ sub-centers connected by edge-sharing, mainly exists in the melt of KBi(MoO4)2.
Anti-Inflammatory Effects of Sulfated Polysaccharide from Sargassum swartzii in Macrophages via Blocking TLR/NF-Κb Signal Transduction
Authors: Jayawardena Thilina U. , Sanjeewa K. K. Asanka , Nagahawatta D. P. , Lee Hyo-Geun , Lu Yu-An , Vaas A. P. J. P. , Abeytunga D. T. U. , Nanayakkara C. M. , Lee Dae-Sung , Jeon You-Jin
Published: November 2020

This study involves enzymatic extraction of fucoidan from Sargassum swartzii and further purification via ion-exchange chromatography. The chemical and molecular characteristics of isolated fucoidan is evaluated concerning its anti-inflammatory potential in RAW 264.7 macrophages under LPS induced conditions. Structural properties of fucoidan were assessed via FTIR and NMR spectroscopy. NO production stimulated by LPS was significantly declined by fucoidan. This was witnessed to be achieved via fucoidan acting on mediators such as iNOS and COX-2 including pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β), with dose dependent down-regulation. Further, the effect is exhibited by the suppression of TLR mediated MyD88, IKK complex, ultimately hindering NF-κB and MAPK activation, proposing its therapeutic applications in inflammation related disorders. The research findings provide an insight in relation to the sustainable utilization of fucoidan from marine brown algae S. swartzii as a potent anti-inflammatory agent in the nutritional, pharmaceutical, and cosmeceutical sectors.
Human Leukocyte Antigen (HLA) Haplotype Does Not Influence the Inflammatory Pattern of Duodenal Lymphocytosis Linked to Irritable Bowel Syndrome
Authors: Losurdo Giuseppe , Todeschini Alessia , Giorgio Floriana , Piscitelli Domenico , Giangaspero Antonio , Ierardi Enzo , Di Leo Alfredo
Published: November 2020

Background and objectives: Duodenal lymphocytosis (DL) is a condition characterized by enhanced infiltration of intraepithelial lymphocytes (IELs) in the duodenal mucosa, and it can be linked to both gluten- and non-gluten-related diseases, such as irritable bowel syndrome (IBS). Materials and methods: We retrospectively selected patients with DL linked to IBS. Formalin-embedded biopsy samples of the duodenum were collected. CD3 lymphocyte immunohistochemistry was used for IELs. The real-time polymerase chain reaction was used to quantify the amount of mRNA coding for tissue transglutaminase 2 (tTG2), interferon-gamma (IFNγ), toll-like receptor 2 (TLR2), and myeloid differentiation primary response 88 (MyD88). All subjects underwent DQ2-8 haplotype analysis. Controls were represented by subjects with IBS without DL. Results: Thirty-two patients with IBS-DL were retrospectively recruited. Fourteen subjects (43.8%) had a DQ2-8 haplotype. DQ2-8 positive subjects had similar levels compared to negative ones for tTG2, IFNγ, TLR2, and MyD88. Cigarette smoke did not influence molecular expression in our study. Smokers had a statistically higher IELs count than non-smokers (54.2 ± 7.7 vs. 36.0 ± 8.8, p < 0.001). A significant, direct correlation between IELs and duodenal expression of IFNγ was found (r = 0.36, p = 0.04). Conclusions: IBS with DL showed higher expression of inflammatory markers than controls, but DQ2-8 haplotype did not seem to affect their expression. Smoking might increase IELs infiltration.
Microstructural Investigation and On-Site Repair of Thin Pd-Ag Alloy Membranes
Authors: Ma Yuyu , Tang Chunhua , Bao Feng , Shao Wei , Xu Tianying , Li Hui , Xu Hengyong
Published: November 2020

Pd membranes act in an important role in H2 purification and H2 production in membrane reactors. Pd-Ag alloy membranes fabricated by consecutive electroless- and electroplating process on alumina tubes exhibited good stability under stringent heating/cooling cycles at a ramp rate of 10 K/min, imitating practical fast initiation or emergency shutdown conditions. Bilayer Pd-Ag membranes can form dense and uniform alloy after thermal treatment for 24 h at 823 K under H2 atmosphere, despite a porous structure due to the development of liquid-like properties above Tamman temperature to enforce the migrativity. On the contrary, alloying under N2 atmosphere resulted in a Pd-enriched layer. This led to a lower H2 flux but superior thermal stability compared to that alloying under H2 atmosphere. The trilayer approach of electroless-plated Pd, electro-polated Ag and electroless-plated Pd is not suitable to achieve homogeneous Pd-Ag alloys, which, on the other hand, presented the occurrence of a small gap between top Pd layer and middle Ag layer, probably due to insufficient wetting during plating process. An on-site repair treatment in analogous to MOCVD (Metal-organic Chemical Vapor Deposition) process was first proposed to extend the lifetime of Pd-Ag membrane, i.e., by vaporizing, and subsequent decomposition of Ag(OOCC2F5) powders to “preferentially” block the pinholes under vacuum and at working temperature of ca. 473–673 K, which effectively reduced the N2 flux by 57.4% compared to the initial value. The H2 flux, however, declined by 16.7% due to carbon deposition on the membrane surface, which requires further investigation. This approach shows some potential for on-site repair without disassembly or cooling to room temperature.
The Effect of Tungstate and Ethanolamines Added in Tap Water on Corrosion Inhibition of Ductile Cast Iron Pipe for Nuclear Power Plants
Authors: Lim Butaek , Kim Kitae , Chang Hyunyoung , Park Heungbae , Kim Youngsik
Published: November 2020

Cast iron is primarily used in buried piping to transport water in the fire protection system of nuclear power plants; ductile cast iron is generally used for domestic nuclear power plants. In general, the fluid used as fire-extinguishing water in such fire protection systems is tap water, and corrosion inhibitors are not currently added. In this study, the synergistic effect of an adsorption barrier (monoethanolamine) and oxidized film in an environment with a corrosion inhibitor (tungstate) is examined, and the corresponding passivation properties are presented. An immersion corrosion test and electrochemical test in tap water to which only tungstate was added showed suppression of corrosion compared to molybdate at the same concentration. The polarization resistance value of a passivation film in tap water mixed with monoethanolamine and tungstate showed better results than that of the molybdate control. A surface analysis in mixed addition tap water also demonstrated that oxygen ions were sufficiently distributed, including at some spheroidized graphite sites, when tungstate was added compared to molybdate. In addition, the amount of tungsten ions adsorbed on the surface was larger than that of molybdenum ions, and it was confirmed that tungsten ions were evenly distributed over the entire surface.
Effect of Starting Microstructures on the Reverse Transformation Kinetics in Low-Carbon Steel
Authors: Hou Junhua , He Binbin
Published: November 2020

The effect of the initial starting microstructures on the austenite reverse transformation kinetics is thoroughly studied in low-carbon steel. The different initial starting microstructures including the ferrite + pearlite, bainite, and martensite are obtained through varied forward transformation. It is found that the bainite phase demonstrates highest reverse transformation rate while the ferrite + pearlite shows the lowest transformation rate. The above observation can be explained through the different grain size of the initial starting microstructures as the grain boundaries could act as the nucleation sites for austenite reverse transformation. The explanation is further substantiated based on the consideration of the reverse transformation kinetics from the martensite microstructure with different grain size.
Effects of Shoulder Geometry on Microstructures and Mechanical Properties of Probeless Friction Stir Spot Welded Aluminum 7075-T651 Sheets
Authors: Chu Xingrong , Yin Meng , Gao Jun , Wang Xiaowei , Wang Yangang
Published: November 2020

In this work, three types of probeless tools (archimedes, involute, and concave tools) were designed. A 7075-T651 sheet of 1.0 mm thickness was welded using the designed probeless tools. It was found that the stir zone and hook defect varied a lot for different joints. Plunge depth was the dominant process parameter for joint property. The joint’s maximum failure load (5.73 kN) was obtained with the concave tool when the target plunge depth was 0.55 mm. Two typical joint fracture modes (shear fracture and plug fracture) were found using three designed tools with different plunge depths, rotation speeds, and dwell times. Shoulder geometry presented little influence on heat generation. Compared with involute grooves, archimedes grooves showed to be more effective on the material flow. The properties of the joints with the archimedes tool were more sensitive to welding parameters. Compared with the flat tool, the concave tool decreased the escape of plasticized material, improved the forge force, and optimized the metallurgical bond at the interface.
Precipitation and Crystallization Used in the Production of Metal Salts for Li-Ion Battery Materials: A Review
Authors: Ma Yiqian , Svärd Michael , Xiao Xiong , Gardner James M. , Olsson Richard T. , Forsberg Kerstin
Published: November 2020

Li-ion battery materials have been widely studied over the past decades. The metal salts that serve as starting materials for cathode and production, including Li2CO3, NiSO4, CoSO4 and MnSO4, are mainly produced using hydrometallurgical processes. In hydrometallurgy, aqueous precipitation and crystallization are important unit operations. Precipitation is mainly used in the processes of impurity removal, separation and preliminary production, while controlled crystallization can be very important to produce a pure product that separates well from the liquid solution. Precipitation and crystallization are often considered in the development of sustainable technologies, and there is still room for applying novel techniques. This review focuses on precipitation and crystallization applied to the production of metal salts for Li-ion battery materials. A number of novel and promising precipitation and crystallization methods, including eutectic freeze crystallization, antisolvent crystallization, and homogeneous precipitation are discussed. Finally, the application of precipitation and crystallization techniques in hydrometallurgical recycling processes for Li-ion batteries are reviewed.
Production of Fe–Ti Alloys from Mixed Slag Containing Titanium and Fe2O3 via Direct Electrochemical Reduction in Molten Calcium Chloride
Authors: Wang Bo , Chen Chao-yi , Li Jun-qi , Wang Lin-zhu , Lan Yuan-pei , Wang Shi-yu
Published: November 2020

High-purity intermetallic β-Ti (FeTi4) and FeTi alloys were prepared via molten salt electrolysis from a titanium-containing waste slag and Fe2O3 mixture using molten CaCl2 salt as the electrolyte. The mixed slag powders were pressed into a pellet that served as a cathode, while a graphite rod served as an anode. The electrochemical process was conducted at 900 °C with a cell voltage of 3.1 V under an inert atmosphere. The formation process of the alloys and the influence of the Ti:Fe atomic ratio on the product were investigated. With an increased proportion of Ti, the phase of the product changed from FeTi/Fe2Ti to FeTi/FeTi4, and different structures were observed. At a Ti:Fe ratio of 1.2:1 in the raw slag, an alloy with a sponge-like morphology and a small amount of FeTi4 were obtained. During the initial stages of electrolysis, a large amount of intermediate product (CaTiO3) was formed, accompanied by an abrupt decrease in current and increase in particle size. The current then increased and Fe2Ti alloy was gradually formed. Finally, as the reaction process extended inside the pellet, the current remained stable and the product mainly contained FeTi and FeTi4 phases. The observed stages, i.e., CaTiO3(TiO2) → Fe2Ti(Ti) → FeTi(FeTi4), were consistent with the thermodynamic analysis.
A Silicon Optical Bench-Based Forward-View Two-Axis Scanner for Microendoscopy Applications
Authors: Zheng Dong , Wang Dingkang , Yoon YK , Xie Huikai
Published: November 2020

Optical microendoscopy enabled by a microelectromechanical system (MEMS) scanning mirror offers great potential for in vivo diagnosis of early cancer inside the human body. However, an additional beam folding mirror is needed for a MEMS mirror to perform forward-view scanning, which drastically increases the diameter of the resultant MEMS endoscopic probe. This paper presents a new monolithic two-axis forward-view optical scanner that is composed of an electrothermally driven MEMS mirror and a beam folding mirror both vertically standing and integrated on a silicon substrate. The mirror plates of the two mirrors are parallel to each other with a small distance of 0.6 mm. The laser beam can be incident first on the MEMS mirror and then on the beam folding mirror, both at 45°. The MEMS scanner has been successfully fabricated. The measured optical scan angles of the MEMS mirror were 10.3° for the x axis and 10.2° for the y axis operated under only 3 V. The measured tip-tilt resonant frequencies of the MEMS mirror were 1590 Hz and 1850 Hz, respectively. With this compact MEMS design, a forward-view scanning endoscopic probe with an outer diameter as small as 2.5 mm can be made, which will enable such imaging probes to enter the subsegmental bronchi of an adult patient.
Eudialyte Group Minerals from the Lovozero Alkaline Massif, Russia: Occurrence, Chemical Composition, and Petrogenetic Significance
Authors: Mikhailova Julia A. , Pakhomovsky Yakov A. , Panikorovskii Taras L. , Bazai Ayya V. , Yakovenchuk Victor N.
Published: November 2020

The Lovozero Alkaline Massif intruded through the Archean granite-gneiss and Devonian volcaniclastic rocks ca. 360 Ma ago and formed a large laccolith-type body. The lower part of the massif (the Layered complex) is composed of regularly repeating rhythms: melanocratic nepheline syenite (lujavrite, at the top), leucocratic nepheline syenite (foyaite), foidolite (urtite). The upper part of the massif (the Eudialyte complex) is indistinctly layered, and lujavrite enriched with eudialyte-group minerals (EGM) prevails there. In this article, we present the results of a study of the chemical composition and petrography of more than 400 samples of the EGM from the main types of rock of the Lovozero massif. In all types of rock, the EGM form at the late magmatic stage later than alkaline clinopyroxenes and amphiboles or simultaneously with it. When the crystallization of pyroxenes and EGM is simultaneous, the content of ferrous iron in the EGM composition increases. The Mn/Fe ratio in the EGM increases during fractional crystallization from lujavrite to foyaite and urtite. The same process leads to an increase in the modal content of EGM in the foyaite of the Layered complex and to the appearance of primary minerals of the lovozerite group in the foyaite of the Eudialyte complex.
Mapping New IOCG Mineral Systems in Brazil: The Vale do Curaçá and Riacho do Pontal Copper Districts
Authors: Hühn Sérgio , Silva Adalene , Ferreira Francisco , Braitenberg Carla
Published: November 2020

The Vale do Curaçá and Riacho do Pontal copper districts are located within the northern part of the Archaean São Francisco Craton and represent two pulses of mineralization. The copper districts have been identified as Iron-Oxide-Copper-Gold (IOCG) classes of deposits. An older metallogenic event associated with the Caraíba copper deposit, which is located in the Vale do Curaçá district, is related to Palaeoproterozoic (ca. 2 to 2.2 Ga) hydrothermal processes. A younger Neoproterozoic (ca. 750 to 570 Ma) episode of volcanism and associated plutonism is represented by the Riacho do Pontal mineral district. Seismic tomography data from across east-central Brazil show that the multiage Carajás province and Vale do Curaçá and Riacho do Pontal copper districts sit along either side of a prominent NW-trending upper lithospheric high-velocity zone. The edges of the high-velocity zone point to long-lived subparallel transcrustal structures that have been the focus of multiple reactivations and copper mineralization events. Regional gravity and magnetic maps show that the Vale do Curaçá copper district extends over an area greater than 110 km by 22 km. The magnetic and gravity values show significant variations correlated with this area. The district includes high gravity values associated with the Caraíba copper mine (>−35 mGal), which has a greater density (3.13 g/cm3) than the nonmineralized host rock density (2.98 g/cm3). The gravity anomaly signature over the Riacho do Pontal copper district is characterized by a 40-km long NW–SE trending Bouguer gravity low. The Ria4 occurrences of the Riacho do Pontal copper district are situated in these regional low-gravity domains. Data from regional airborne magnetic and ground gravity surveys were inverted to obtain a 3D magnetic susceptibility and density model, respectively, for the known districts. The results show that the Caraíba deposit is characterized by a both dense and magnetic source showing structural control by thrust shear zones. The 2D and 3D geological models show two main NNW prospective trends. Trends I and II have a sigmoidal shear shape and are positioned in the contact zone between domains with high magnetic susceptibility (SI > 0.005) and density > 0 g/cm3). Trend I is 40 km × 10 km in size and hosts the Caraíba, Surubim, and Vermelho copper mines and other minor deposits. The results obtained from the 3D magnetic inversion model for the region of the Riacho do Pontal district show weak magnetic anomaly highs extending along a NW–SE magnetic gradient trend. The gradient is related to mapped shear zones that overprint older and deeper NE–SW features of the São Francisco cratonic root. The area includes high gravity values associated with the Caraíba copper deposit, which has a greater density (3.13 g/cm3) than the nonmineralized host rock density (2.4 g/cm3).