bluuebunny/crossref_metadata_2025 huggingface dataset:
Exposure to Environmental and Occupational Particulate Air Pollution as a Potential Contributor to Neurodegeneration and Diabetes: A Systematic Review of Epidemiological Research
Authors: Dimakakou Eirini , Johnston Helinor J. , Streftaris George , Cherrie John W.
Published: August 2018

It has been hypothesised that environmental air pollution, especially airborne particles, is a risk factor for type 2 diabetes mellitus (T2DM) and neurodegenerative conditions. However, epidemiological evidence is inconsistent and has not been previously evaluated as part of a systematic review. Our objectives were to carry out a systematic review of the epidemiological evidence on the association between long-term exposure to ambient air pollution and T2DM and neurodegenerative diseases in adults and to identify if workplace exposures to particles are associated with an increased risk of T2DM and neurodegenerative diseases. Assessment of the quality of the evidence was carried out using the GRADE system, which considers the quality of the studies, consistency, directness, effect size, and publication bias. Available evidence indicates a consistent positive association between ambient air pollution and both T2DM and neurodegeneration risk, such as dementia and a general decline in cognition. However, corresponding evidence for workplace exposures are lacking. Further research is required to identify the link and mechanisms associated with particulate exposure and disease pathogenesis and to investigate the risks in occupational populations. Additional steps are needed to reduce air pollution levels and possibly also in the workplace environment to decrease the incidence of T2DM and cognitive decline.
BIM-GIS Integration as Dedicated and Independent Course for Geoinformatics Students: Merits, Challenges, and Ways Forward
Authors: Hijazi Ihab , Donaubauer Andreas , Kolbe Thomas H.
Published: August 2018

Information mined from building information models as well as associated geographical data and Geographic Information System (GIS) analyses can increase the success of construction processes and asset management, including buildings, roads, and public facilities. The integration of information from both domains requires high expertise in both spheres. The existing B.Sc and M.Sc. programs linked to the built environment at the Technical University of Munich offer courses for the Building Information Model (BIM) and GIS that are distributed among study programs in Civil Engineering, Architecture, and Geomatics. Students graduating as professionals in one of these domains rarely know how to solve pre-defined technical problems associated with the integration of information from BIM and GIS. Students in such programs seldom practice skills needed for the integration of information from BIM and GIS at a level that is needed in working life. Conversely, the technologies in both domains create artificial boundaries that do not exist in reality—for example, water and electricity would not be of use if the utilities terminated in front of buildings. To bring a change and bridge the gap between BIM and GIS, a change in the teaching methods of BIM/GIS needs to be considered. The Technical University of Munich (TUM) has developed a master’s course (M.Sc. course) for students in Geoinformatics which focuses on competencies required to achieve BIM/GIS integration. This paper describes the course development process and provides a unique perspective on the curriculum and subjects. It also presents the course objective, course development, the selection and development of learning materials, and the assessment of the intended learning outcome of the course. The developed course is validated through a questionnaire, and feedback is provided by participants of the BIM/GIS integration workshop representing a panel of experts in the domain.
Exploring Railway Network Dynamics in China from 2008 to 2017
Authors: Huang Yaping , Lu Shiwei , Yang Xiping , Zhao Zhiyuan
Published: August 2018

China’s high speed rail (HSR) network has been rapidly constructed and developed during the past 10 years. However, few studies have reported the spatiotemporal changes of railway network structures and how those structures have been affected by the operation of high speed rail systems in different periods. This paper analyzes the evolving network characteristics of China’s railway network during each of the four main stages of HSR development over a 10-year period. These four stages include Stage 1, when no HSR was in place prior to August 2008; Stage 2, when several HSR lines were put into operation between August 2008, and July 2011; Stage 3, when the network skeleton of most main HSR lines was put into place. This covered the period until January 2013. Finally, Stage 4 covers the deep intensification of several new HSR lines and the rapid development of intercity-HSR railway lines between January 2013, and July 2017. This paper presents a detailed analysis of the timetable-based statistical properties of China’s railway network, as well as the spatiotemporal patterns of the more than 2700 stations that have been affected by the opening of HSR lines and the corresponding policy changes. Generally, we find that the distribution of both degrees and strengths are characterized by scale-free patterns. In addition, the decreasing average path length and increasing network clustering coefficient indicate that the small world characteristic is more significant in the evolution of China’s railway network. Correlations between different network indices are explored, in order to further investigate the dynamics of China’s railway system. Overall, our study offers a new approach for assessing the growth and evolution of a real railway network based on train timetables. Our study can also be referenced by policymakers looking to adjust HSR operations and plan future HSR routes.
Analyzing the Tagging Quality of the Spanish OpenStreetMap
Authors: Almendros-Jiménez Jesús M. , Becerra-Terón Antonio
Published: August 2018

In this paper, a framework for the assessment of the quality of OpenStreetMap is presented, comprising a batch of methods to analyze the quality of entity tagging. The approach uses Taginfo as a reference base and analyses quality measures such as completeness, compliance, consistence, granularity, richness and trust . The framework has been used to analyze the quality of OpenStreetMap in Spain, comparing the main cities of Spain. Also a comparison between Spain and some major European cities has been carried out. Additionally, a Web tool has been also developed in order to facilitate the same kind of analysis in any area of the world.
Aggregation of Human Trophoblast Cells into Three-Dimensional Culture System Enhances Anti-Inflammatory Characteristics through Cytoskeleton Regulation
Authors: Seno Kotomi , Munakata Yasuhisa , Sano Michiya , Kawahara-Miki Ryouka , Takahashi Hironori , Ohkuchi Akihide , Iwata Hisataka , Kuwayama Takehito , Shirasuna Koumei
Published: August 2018

Background: Three-dimensional (3D) culture changes cell characteristics and function, suggesting that 3D culture provides a more physiologically relevant environment for cells compared with 2D culture. We investigated the differences in cell functions depending on the culture model in human trophoblast cells (Sw.71). Methods: Sw.71 cells were incubated in 2D monolayers or simple 3D spheroids. After incubation, cells were corrected to assess RNA-seq transcriptome or protein expression, and culture medium were corrected to detect cytokines. To clarify the role of actin cytoskeleton, spheroid Sw.71 cells were treated mycalolide B (inhibitor of actin polymerization) in a 3D culture. Results: RNA-seq transcriptome analysis, results revealed that 3D-cultured cells had a different transcriptional profile compared with 2D-cultured cells, especially regarding inflammation-related molecules. Although interleukin-6 (IL-6) mRNA level was higher in 3D-culured cells, its secretion levels were higher in 2D-cultured cells. In addition, the levels of mRNA and protein expression of regnase-1, regulatory RNase of inflammatory cytokine, significantly increased in 3D culture, suggesting post-translational modification of IL-6 mRNA via regnase-1. Treatment with mycalolide B reduced cell-to-cell contact to build 3D formation and increased expression of actin cytoskeleton, resulting in increased IL-6 secretin. Conclusion: Cell dimensionality plays an essential role in governing the spatiotemporal cellular outcomes, including inflammatory cytokine production and its negative regulation associated with regnase-1.
Developing Hollow-Channel Gold Nanoflowers as Trimodal Intracellular Nanoprobes
Authors: Ye Sunjie , Wheeler May C. , McLaughlan James R. , Tamang Abiral , Diggle Christine P. , Cespedes Oscar , Markham Alex F. , Coletta P. Louise , Evans Stephen D.
Published: August 2018

Gold nanoparticles-enabled intracellular surface-enhanced Raman spectroscopy (SERS) provides a sensitive and promising technique for single cell analysis. Compared with spherical gold nanoparticles, gold nanoflowers, i.e., flower-shaped gold nanostructures, can produce a stronger SERS signal. Current exploration of gold nanoflowers for intracellular SERS has been considerably limited by the difficulties in preparation, as well as background signal and cytotoxicity arising from the surfactant capping layer. Recently, we have developed a facile and surfactant-free method for fabricating hollow-channel gold nanoflowers (HAuNFs) with great single-particle SERS activity. In this paper, we investigate the cellular uptake and cytotoxicity of our HAuNFs using a RAW 264.7 macrophage cell line, and have observed effective cellular internalization and low cytotoxicity. We have further engineered our HAuNFs into SERS-active tags, and demonstrated the functionality of the obtained tags as trimodal nanoprobes for dark-field and fluorescence microscopy imaging, together with intracellular SERS.
Chitosan-Based Nanofibrous Membrane Unit with Gradient Compositional and Structural Features for Mimicking Calcified Layer in Osteochondral Matrix
Authors: Liu Jiaoyan , Fang Qing , Yu Xiaofeng , Wan Ying , Xiao Bo
Published: August 2018

Chitosan (CH), silk fibroin (SF), and hydroxyapatite (HA) were used to prepare CH/SF/HA composites and the resulting composites were electrospun into nanofibrous membrane units with gradient compositional and structural features. The optimal membrane unit was used together with CH/HA and CH/SF composites to fabricate a type of three-layer scaffold that is intended for osteochondral repair. The bottom layer of the scaffold was built with CH/HA composites and it served as a subchondral layer, the integrated nanofibrous membrane unit functioned as the middle layer for mimicking the calcified layer and the top layer was constructed using CH/SF composites for acting as a chondral layer. The nanofibrous membrane unit was found to be permeable to some molecules with limited molecular weight and was able to prevent the seeded cells from migrating cross the unit, functioning approximately like the calcified layer in the osteochondral matrix. Layered scaffolds showed abilities to promote the growth of both chondrocytes and osteoblasts that were seeded in their chondral layer and bony layer, respectively, and they were also able to support the phenotype preservation of seeded chondrocytes and the mineralization of neotissue in the bony layer. Results suggest that this type of layered scaffolds can function as an analogue of the osteochondral matrix and it has potential in osteochondral repair.
Clinically Relevant Anti-Inflammatory Agents for Chemoprevention of Colorectal Cancer: New Perspectives
Authors: Mohammed Altaf , Yarla Nagendra Sastry , Madka Venkateshwar , Rao Chinthalapally V.
Published: August 2018

Substantial efforts are underway for prevention of early stages or recurrence of colorectal cancers (CRC) or new polyp formation by chemoprevention strategies. Several epidemiological, clinical and preclinical studies to date have supported the chemopreventive potentials of several targeted drug classes including non-steroidal anti-inflammatory drugs (NSAIDs) (aspirin, naproxen, sulindac, celecoxib, and licofelone), statins and other natural agents—both individually, and in combinations. Most preclinical trials although were efficacious, only few agents entered clinical trials and have been proven to be potential chemopreventive agents for colon cancer. However, there are limitations for these agents that hinder their approval by the food and drug administration for chemoprevention use in high-risk individuals and in patients with early stages of CRC. In this review, we update the recent advancement in pre-clinical and clinical development of selected anti-inflammatory agents (aspirin, naproxen, sulindac, celecoxib, and licofelone) and their combinations for further development as novel colon cancer chemopreventive drugs. We provide further new perspectives from this old research, and insights into precision medicine strategies to overcome unwanted side-effects and overcoming strategies for colon cancer chemoprevention.
Augmented Insulin and Leptin Resistance of High Fat Diet-Fed APPswe/PS1dE9 Transgenic Mice Exacerbate Obesity and Glycemic Dysregulation
Authors: Lee Yi-Heng , Hsu Hao-Chieh , Kao Pei-Chen , Shiao Young-Ji , Yeh Skye Hsin-Hsien , Shie Feng-Shiun , Hsu Shu-Meng , Yeh Chih-Wen , Liu Hui-Kang , Yang Shi-Bing , Tsay Huey-Jen
Published: August 2018

Alzheimer’s disease (AD), a progressive neurodegenerative disease is highly associated with metabolic syndromes. We previously demonstrated that glycemic dysregulation and obesity are augmented in high fat diet (HFD)-treated APPswe/PS1dE9 (APP/PS1) transgenic mice. In the current study, the underlying mechanism mediating exacerbated metabolic stresses in HFD APP/PS1 transgenic mice was further examined. APP/PS1 mice developed insulin resistance and, consequently, impaired glucose homeostasis after 10 weeks on HFD. [18F]-2-fluoro-2-deoxy-d-glucose ([18F]-FDG) positron emission tomography showed that interscapular brown adipose tissue is vulnerable to HFD and AD-related pathology. Chronic HFD induced hyperphagia, with limited effects on basal metabolic rates in APP/PS1 transgenic mice. Excessive food intake may be caused by impairment of leptin signaling in the hypothalamus because leptin failed to suppress the food intake of HFD APP/PS1 transgenic mice. Leptin-induced pSTAT3 signaling in the arcuate nucleus was attenuated. Dysregulated energy homeostasis including hyperphagia and exacerbated obesity was elicited prior to the presence of the amyloid pathology in the hypothalamus of HFD APP/PS1 transgenic mice; nevertheless, cortical neuroinflammation and the level of serum Aβ and IL-6 were significantly elevated. Our study demonstrates the pivotal role of AD-related pathology in augmenting HFD-induced insulin and leptin resistance and impairing hypothalamic regulation of energy homeostasis.
Na/K-ATPase Signaling and Cardiac Pre/Postconditioning with Cardiotonic Steroids
Authors: Marck Pauline V. , Pierre Sandrine V.
Published: August 2018

The first reports of cardiac Na/K-ATPase signaling, published 20 years ago, have opened several major fields of investigations into the cardioprotective action of low/subinotropic concentrations of cardiotonic steroids (CTS). This review focuses on the protective cardiac Na/K-ATPase-mediated signaling triggered by low concentrations of ouabain and other CTS, in the context of the enduring debate over the use of CTS in the ischemic heart. Indeed, as basic and clinical research continues to support effectiveness and feasibility of conditioning interventions against ischemia/reperfusion injury in acute myocardial infarction (AMI), the mechanistic information available to date suggests that unique features of CTS-based conditioning could be highly suitable, alone /or as a combinatory approach.
The Therapeutic Strategy of HDAC6 Inhibitors in Lymphoproliferative Disease
Authors: Cosenza Maria , Pozzi Samantha
Published: August 2018

Histone deacetylases (HDACs) are master regulators of chromatin remodeling, acting as epigenetic regulators of gene expression. In the last decade, inhibition of HDACs has become a target for specific epigenetic modifications related to cancer development. Overexpression of HDAC has been observed in several hematologic malignancies. Therefore, the observation that HDACs might play a role in various hematologic malignancies has brought to the development of HDAC inhibitors as potential antitumor agents. Recently, the class IIb, HDAC6, has emerged as one potential selective HDACi. This isoenzyme represents an important pharmacological target for selective inhibition. Its selectivity may reduce the toxicity related to the off-target effects of pan-HDAC inhibitors. HDAC6 has also been studied in cancer especially for its ability to coordinate a variety of cellular processes that are important for cancer pathogenesis. HDAC6 has been reported to be overexpressed in lymphoid cells and its inhibition has demonstrated activity in preclinical and clinical study of lymphoproliferative disease. Various studies of HDAC6 inhibitors alone and in combination with other agents provide strong scientific rationale for the evaluation of these new agents in the clinical setting of hematological malignancies. In this review, we describe the HDACs, their inhibitors, and the recent advances of HDAC6 inhibitors, their mechanisms of action and role in lymphoproliferative disorders.
Correction: Chang, C.-H.; et al. Secreted Protein Acidic and Rich in Cysteine (SPARC) Enhances Cell Proliferation, Migration, and Epithelial Mesenchymal Transition, and SPARC Expression Is Associated with Tumor Grade in Head and Neck Cancer. Int. J. Mol. Sci. 2017, 18, 1556
Authors: Chang Chih-Hau , Yen Meng-Chi , Liao Ssu-Hui , Hsu Yu-Ling , Lai Chung-Sheng , Chang Kao-Ping , Hsu Ya-Ling
Published: August 2018

We would like to submit the correction to our published paper [1]. [...]
Genetic and Physio-Biochemical Characterization of a Novel Premature Senescence Leaf Mutant in Rice (Oryza sativa L.)
Authors: He Yan , Zhang Zhihong , Li Liangjian , Tang Shaoqing , Wu Jian-Li
Published: August 2018

Premature senescence greatly affects the yield production and the grain quality in plants, although the molecular mechanisms are largely unknown. Here, we identified a novel rice premature senescence leaf 85 (psl85) mutant from ethyl methane sulfonate (EMS) mutagenesis of cultivar Zhongjian100 (the wild-type, WT). The psl85 mutant presented a distinct dwarfism and premature senescence leaf phenotype, starting from the seedling stage to the mature stage, with decreasing level of chlorophyll and degradation of chloroplast, declined photosynthetic capacity, increased content of malonaldehyde (MDA), upregulated expression of senescence-associated genes, and disrupted reactive oxygen species (ROS) scavenging system. Moreover, endogenous abscisic acid (ABA) level was significantly increased in psl85 at the late aging phase, and the detached leaves of psl85 showed more rapid chlorophyll deterioration than that of WT under ABA treatment, indicating that PSL85 was involved in ABA-induced leaf senescence. Genetic analysis revealed that the premature senescence leaf phenotype was controlled by a single recessive nuclear gene which was finally mapped in a 47 kb region on the short arm of chromosome 7, covering eight candidate open reading frames (ORFs). No similar genes controlling a premature senescence leaf phenotype have been identified in the region, and cloning and functional analysis of the gene is currently underway.
Comparative Analysis of Transcriptomes to Identify Genes Associated with Fruit Size in the Early Stage of Fruit Development in Pyrus pyrifolia
Authors: Jiang Shuang , An Haishan , Luo Jun , Wang Xiaoqing , Shi Chunhui , Xu Fanjie
Published: August 2018

Pear (Pyrus L.) is an important commercial fruit in the world. The fruit size is one of the important characters in fruit quality. The previous research reported that the fruit size of pear was mainly caused by the number of cell in about 40 days after blossom (DAB) in nature. However, studies about the mechanisms underlying cell division in young fruit development are very limited in pear. Two pear accessions codenamed ‘GH59B’ with big fruit and ‘GH81S’ with small fruit in three stages were sampled and the RNA-seq high-throughput sequencing was used to evaluate changes of gene transcription levels in the early stage of fruit development. The difference of cell size among two samples was little in 40 DAB, implying that the difference of the fruit size was caused by the number of the cell. More than 274,517,982 high quality reads from six libraries of fruit development were sequenced. A total of 797 differentially expressed genes (DEGs) were identified. Three cytokinin dehydrogenase genes and two gibberellin 2-beta-dioxygenase gene were identified in the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to zeatin and gibberellin. Their expression was upregulated at 20 DAB in ‘GH81S’ and at 30 DAB in ‘GH59B’, suggesting that the small fruit size might be related to the early degradation of cytokinin and gibberellin inducing a short period of cell division. A total of 38 DEGs of transcription factors were found and 23 DEGs including NAC, ERF and bHLH transcription factors were highly related with cytokinin dehydrogenase and gibberellin dioxygenase genes. Altogether, the results of the present study provide information from a comprehensive gene expression analysis and insight into the molecular mechanism underlying the difference of fruit size in Pyrus pyrifolia.
Neutrophil Extracellular Traps as an Adhesion Substrate for Different Tumor Cells Expressing RGD-Binding Integrins
Authors: Monti Marcello , De Rosa Viviana , Iommelli Francesca , Carriero Maria Vincenza , Terlizzi Cristina , Camerlingo Rosa , Belli Stefania , Fonti Rosa , Di Minno Giovanni , Del Vecchio Silvana
Published: August 2018

Neutrophil extracellular traps (NETs), in addition to their function as a host defense mechanism, play a relevant role in thrombus formation and metastatic dissemination of cancer cells. Here we screened different cancer cell lines endogenously expressing a variety of integrins for their ability to bind to NETs. To this end, we used NETs isolated from neutrophil-like cells as a substrate for adhesion assays of HT1080, U-87 MG, H1975, DU 145, PC-3 and A-431 cells. Levels of α5, αIIb, αv, β1, β3 and β5 chains were determined by western blot analysis in all cell lines and levels of whole integrins on the plasma membrane were assessed by fluorescence-activated cell sorting (FACS) analysis. We found that high levels of α5β1, αvβ3 and αvβ5 enhance cell adhesion to NETs, whereas low expression of α5β1 prevents cell attachment to NETs. Excess of cyclic RGD peptide inhibited cell adhesion to NETs by competing with fibronectin within NETs. The maximal reduction of such adhesion was similar to that obtained by DNase 1 treatment causing DNA degradation. Our findings indicate that NETs from neutrophil-like cells may be used as a substrate for large screening of the adhesion properties of cancer cells expressing a variety of RGD-binding integrins.
Nest Population Structure and Wood Litter Consumption by Microcerotermes indistinctus (Isoptera) in a Seasonally Dry Tropical Forest, Northeastern Brazil
Authors: R. B. Barca Reberth , F. Lucena Emanuelly , Vasconcellos Alexandre
Published: August 2018

Termites are abundant arthropods in tropical ecosystems and actively participate in the process of litter decomposition. The objective of this study was to evaluate the population structure of Microcerotermes indistinctus in arboreal nests and to estimate their contribution to the consumption of wood litter in an area of Caatinga, a type of seasonally dry tropical forest located in the Brazilian semi-arid region. The populations of fifteen nests were quantified and separated into castes, “larvae”, and eggs. Wood blocks of four typical Caatinga species were offered to termites under laboratory conditions. Litter production was estimated in the area over the course of one year. The mean population size of M. indistinctus was 73,897 individuals/nest, while the mean nest density in the area was 25 active nests/ha. Total consumption of the four types of wood was estimated to be 10.5 mg of wood/g termite (fresh weight)/day. Based on consumption and population size, M. indistinctus consumes 0.35% of the total litter and 1.71% of the annual production of branches and twigs in the area. Wood-consuming termites are highly affected by anthropogenic disturbances in the semi-arid region of Brazil, putting the ecosystem services they perform related to the process of litter decomposition at risk.
Intravenous Colistin Monotherapy versus Combination Therapy against Carbapenem-Resistant Gram-Negative Bacteria Infections: Meta-Analysis of Randomized Controlled Trials
Authors: Cheng I-Ling , Chen Yu-Hung , Lai Chih-Cheng , Tang Hung-Jen
Published: August 2018

This meta-analysis aims to compare intravenous colistin monotherapy and colistin-based combination therapy against carbapenem-resistant gram-negative bacteria (GNB) infections. PubMed, Embase, and Cochrane databases were searched up to July 2018. Only randomized controlled trials (RCTs) evaluating colistin alone and colistin-based combination therapy in the treatment of carbapenem-resistant GNB infections were included. The primary outcome was all-cause mortality. Five RCTs including 791 patients were included. Overall, colistin monotherapy was associated with a risk ratio (RR) of 1.03 (95% confidence interval (CI), 0.89–1.20, I2 = 0%) for all-cause mortality compared with colistin-based combination therapy. The non-significant difference was also detected in infection-related mortality (RR, 1.23, 95% CI, 0.91–1.67, I2 = 0%) and microbiologic response (RR, 0.86, 95% CI, 0.72–1.04, I2 = 62%). In addition, no significant difference was observed in the subgroup analysis—high or low dose, with or without a loading dose, carbapenem-resistant Acinetobacter baumannii infections, and in combination with rifampicin. Finally, colistin monotherapy was not associated with lower nephrotoxicity than colistin combination therapy (RR, 0.98; 95% CI, 0.84–1.21, I2 = 0%). Based on the analysis of the five RCTs, no differences were found between colistin monotherapy and colistin-based combination therapy against carbapenem-resistant GNB infections, especially for A. baumannii infections.
Salivary Biomarkers of Oxidative Stress in Children with Chronic Kidney Disease
Authors: Maciejczyk Mateusz , Szulimowska Julita , Skutnik Anna , Taranta-Janusz Katarzyna , Wasilewska Anna , Wiśniewska Natalia , Zalewska Anna
Published: August 2018

There are still missing non-invasive biomarkers of chronic kidney disease (CKD) in children. Therefore, the aim of the study was to evaluate oxidative stress indicators in the non-stimulated (NWS) and stimulated saliva (SWS) of CKD children (n = 25) and healthy controls (n = 25). Salivary antioxidants (catalase (CAT), peroxidase (Px), superoxide dismutase (SOD), uric acid (UA), reduced glutathione (GSH), albumin), redox status (total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI)), and oxidative damage products (advanced glycation end products (AGE), advanced oxidation protein products (AOPP), malondialdehyde (MDA)) were evaluated. We have demonstrated the significantly higher activity of SWS GPx and SOD, as well as elevated concentrations of UA and albumin in NWS and SWS of CKD children vs. the control group. TAC, TOS and OSI were significantly higher only in SWS, while oxidative damage products (AGE, AOPP and MDA) were significantly higher in both NWS and SWS of CKD children. ROC analysis showed a considerably high diagnostic value of AOPP in both NWS and SWS of CKD children compared to controls (AUC = 0.92; 0.98). CKD is responsible for disturbances in salivary antioxidant systems and oxidative damage to proteins and lipids. Salivary AOPP can be a potential biomarker of CKD in children.
Brazilian Bimodal Bilinguals as Heritage Signers
Authors: Quadros Ronice Müller de , Lillo-Martin Diane
Published: August 2018

This paper presents an analysis of heritage signers: bimodal bilinguals, who are adult hearing children of Deaf parents who acquired sign language at home with their parents and the spoken language from the surrounding community. Analyzing heritage language with bimodal bilinguals who possess pairs of languages in different modalities provides a new kind of evidence for understanding the heritage language phenomenon as well as for theoretical issues regarding human language. Language production data were collected from four Brazilian bimodal bilinguals separately in both sign and speech, as well as from monolingual comparison Deaf signers and hearing speakers. The data were subsequently analyzed for various grammatical components. As with other types of heritage speakers, we observed a great degree of individual variation in the sign (heritage) language of balanced participants who patterned similarly to the monolingual signers, compared to those whose use of sign language differed greatly from monolinguals. One participant showed some weaknesses in the second (spoken) language. We approach the variation in language fluency in the two languages by considering the different contexts of language development and continuing use.
Process Parameter Effects on Biocompatible Thermoplastic Sheets Produced by Incremental Forming
Authors: Sabater Marc , Garcia-Romeu M. Luisa , Vives-Mestres Marina , Ferrer Ines , Bagudanch Isabel
Published: August 2018

There has been increasing interest in the processes that enable part customization and small-batch production in recent years. The prosthetic sector, in which biocompatible materials are used, is one of the areas that requires these types of processes; Incremental Sheet Forming (ISF) technology can meet these requirements. However, the biocompatible thermoplastic polymers formed by this technology have not yet been tested. Hence, the aim of this paper is to cover this gap in our knowledge by analyzing the effects of process parameters on the ISF process with the aim of optimizing these parameters before the actual production of, in this case, customized prostheses. Tests with polycaprolactone (PCL) and ultra-high molecular weight polyethylene (UHMWPE) were performed. Maximum force, surface roughness and maximum depth were statistically analyzed by means of response surface methodology and survival analysis. Spindle speed and tool diameter were shown to be the most influential process parameters in terms of maximum forming force and surface roughness for both materials. In contrast, survival analysis applied to maximum depth showed a greater influence of tool diameter in PCL sheets and a greater influence of spindle speed in the case of UHMWPE.
Corrosion Behavior and Mechanism of Basalt Fibers in Sodium Hydroxide Solution
Authors: Tang Chunhong , Jiang Hao , Zhang Xu , Li Guangyao , Cui Junjia
Published: August 2018

In this paper, the corrosion mechanism and tensile properties of basalt fibers in sodium hydroxide (NaOH) solution with various concentrations and temperatures were studied. The hydroxyl ions disrupt the –Si–O–Si– and –Si–O–Al– bonds leading to the formation of insoluble hydroxides. With the continuation of the hydration reaction, a hydration layer (corrosion shell) with high content of calcium, iron, manganese and titanium ions was formed on the fiber surface. The corrosion shell enabled an increase in the strength and elongation at break of basalt fibers, significantly. Results showed that the tensile strength of fibers was strongly dependent on temperature and concentration. After the basalt fibers were immersed in 1 mol/L NaOH solution at 50 °C for 1 h, 3 h, 6 h, 1 day and 3 days, their retention ratios of strength were 67.6%, 57.8%, 52.5%, 49.0%, 58.2%, respectively. Higher temperature accelerated the corrosion rate of basalt fibers, shortened the formation time of the corrosion shell and increased mass loss. From 25 to 70 °C, the mass loss of fibers increased from 2.4% to 33.8% for fibers immersed in 1 mol/L NaOH for 3 days. The experimental results from quantitative x-ray fluorescence (XRF) showed that the mass loss of basalt fibers was mainly due to the leaching of silicon, aluminum and potassium ions.
Eco-Friendly Cavity-Containing Iron Oxides Prepared by Mild Routes as Very Efficient Catalysts for the Total Oxidation of VOCs
Authors: Sanchis Rut , Alonso-Domínguez Daniel , Dejoz Ana , Pico María Pilar , Álvarez-Serrano Inmaculada , García Tomás , López María Luisa , Solsona Benjamín
Published: August 2018

Iron oxides (FeOx) are non-toxic, non-expensive and environmentally friendly compounds, which makes them good candidates for many industrial applications, among them catalysis. In the present article five catalysts based on FeOx were synthesized by mild routes: hydrothermal in subcritical and supercritical conditions (Fe-HT, Few200, Few450) and solvothermal (Fe-ST1 and Fe-ST2). The catalytic activity of these catalysts was studied for the total oxidation of toluene using very demanding conditions with high space velocities and including water and CO2 in the feed. The samples were characterized by X-ray diffraction (XRD), scanning and high-resolution transmission electron microscopy (SEM and HRTEM), X-ray photoelectron spectroscopy (XPS) and nitrogen adsorption-desorption isotherms. It was observed that the most active catalyst was a cavity-containing porous sample prepared by a solvothermal method with a relatively high surface area (55 m2 g−1) and constituted by flower-like aggregates with open cavities at the catalyst surface. This catalyst displayed superior performance (100% of toluene conversion at 325 °C using highly demanding conditions) and this performance can be maintained for several catalytic cycles. Interestingly, the porous iron oxides present not only a higher catalytic activity than the non-porous but also a higher specific activity per surface area. The high activity of this catalyst has been related to the possible synergistic effect of compositional, structural and microstructural features emphasizing the role of the surface area, the crystalline phase present, and the properties of the surface.
Combined Calorimetry, Thermo-Mechanical Analysis and Tensile Test on Welded EN AW-6082 Joints
Authors: Wiechmann Philipp , Panwitt Hannes , Heyer Horst , Reich Michael , Sander Manuela , Kessler Olaf
Published: August 2018

Wide softening zones are typical for welded joints of age hardened aluminium alloys. In this study, the microstructure evolution and distribution of mechanical properties resulting from welding processes of the aluminium alloy EN AW-6082 (AlSi1MgMn) was analysed by both in-situ and ex-situ investigations. The in-situ thermal analyses included differential scanning calorimetry (DSC), which was used to characterise the dissolution and precipitation behaviour in the heat affected zone (HAZ) of welded joints. Thermo-mechanical analysis (TMA) by means of compression tests was used to determine the mechanical properties of various states of the microstructure after the welding heat input. The necessary temperature–time courses in the HAZ for these methods were measured using thermocouples during welding. Additionally, ex-situ tensile tests were done both on specimens from the fusion zone and on welded joints, and their in-depth analysis with digital image correlation (DIC) accompanied by finite element simulations serve for the description of flow curves in different areas of the weld. The combination of these methods and the discussion of their results make an essential contribution to understand the influence of welding heat on the material properties, particularly on the softening behaviour. Furthermore, the distributed strength characteristic of the welded connections is required for an applicable estimation of the load-bearing capacity of welded aluminium structures by numerical methods.
Computing Topological Indices and Polynomials for Line Graphs
Authors: Imran Shahid , Siddiqui Muhammad Kamran , Imran Muhammad , Nadeem Muhammad Faisal
Published: August 2018

A topological index is a number related to the atomic index that allows quantitative structure–action/property/toxicity connections. All the more vital topological indices correspond to certain physico-concoction properties like breaking point, solidness, strain vitality, and so forth, of synthetic mixes. The idea of the hyper Zagreb index, multiple Zagreb indices and Zagreb polynomials was set up in the substance diagram hypothesis in light of vertex degrees. These indices are valuable in the investigation of calming exercises of certain compound systems. In this paper, we computed the first and second Zagreb index, the hyper Zagreb index, multiple Zagreb indices and Zagreb polynomials of the line graph of wheel and ladder graphs by utilizing the idea of subdivision.
An Efficient Polymer Inclusion Membrane-Based Device for Cd Monitoring in Seawater
Authors: Ait Khaldoun Ibrahim , Mitiche Lynda , Sahmoune Amar , Fontàs Clàudia
Published: August 2018

A novel and simple device that includes a polymer inclusion membrane (PIM) has been prepared and tested for the first time to detect low concentration levels of cadmium in seawater. The ionic liquid trihexyl (tetradecyl) phosphonium chloride (THTDPCl) has been shown to be an effective extractant when incorporated in a PIM that uses cellulose triacetate (CTA) as a polymer. However, it has been reported that the use of a plasticizer is mandatory to ensure an effective transport, which uses both ultrapure water and a nitric acid solution as a stripping phase. A special device incorporating a PIM made of 50% CTA, 40% nitrophenyl octyl ether (as a plasticizer), and 10% THTDPCl, effectively allows the quantitative transport and preconcentration of 10 µg L−1 Cd from seawater samples to a stripping phase consisting of 0.5 M HNO3 solution. This study shows that the efficiency of the PIM system is not affected by high salinity nor the presence of large amounts of other ions, and can thus facilitate Cd monitoring in seawater samples.
Crack Propagation Mechanisms for Creep Fatigue: A Consolidated Explanation of Fundamental Behaviours from Initiation to Failure
Authors: Liu Dan , Pons Dirk John
Published: August 2018

Background—Creep-fatigue damage is generally identified as the combined effect of fatigue and creep. This behaviour is macroscopically described by crack growth, wherein fatigue and creep follow different principles. Need—Although the literature contains many studies that explore the crack-growth path, there is a lack of clear models to link these disparate findings and to explain the possible mechanisms at a grain-based level for crack growth from crack initiation, through the steady stage (this is particularly challenging), ending in structural failure. Method—Finite element (FE) methods were used to provide a quantitative validation of the grain-size effect and the failure principles for fatigue and creep. Thereafter, a microstructural conceptual framework for the three stages of crack growth was developed by integrating existing crack-growth microstructural observations for fatigue and creep. Specifically, the crack propagation is based on existing mechanisms of plastic blunting and diffusion creep. Results—Fatigue and creep effects are treated separately due to their different damage principles. The possible grain-boundary behaviours, such as the mismatch behaviour at grain boundary due to creep deformation, are included. The framework illustrates the possible situations for crack propagation at a grain-based level, particularly the situation in which the crack encounters the grain boundary. Originality—The framework is consistent with the various creep and fatigue microstructure observations in the literature, but goes further by integrating these together into a logically consistent framework that describes the overall failure process at the microstructural level.
Mechanisms for Improvement of Weld Appearance in Autogenous Fiber Laser Welding of Thick Stainless Steels
Authors: Zhang Mingjun , Chen Shun , Zhang Yingzhe , Chen Genyu , Bi Zhuming
Published: August 2018

High-power fiber laser welding is an efficient and effective way to produce heavy section structures. However, there is a significant challenge in producing the welds with free of imperfections such as nail-head-shaped welds, spatters, and root sagging. This is partially due to a lack of understanding of the welding mechanism of high-power fiber laser. In this paper, we were especially interested in the mechanism to improve the appearance of welds, and we focused on the autogenous laser welding on thick stainless steel plates by a 10 kW fiber laser. To look into the relations of process parameters and the quality of welds, a high-speed imaging system was applied to observe the molten pool flow and vapor plume during the welding process. The appearances of welds subjected to different welding conditions were analyzed. The results showed that (1) nail-head-shaped welds were suppressed by using a gas jet during laser welding process. (2) In the forward welding, a gentle upwelling molten metal flow on the rear keyhole wall, a deeper weld pool and a weaker vapor plume resulted in no spatter. (3) The gravity affected the formation of underfills and root sagging significantly during autogenous laser welding of thick plates. (4) When the workpiece was placed vertically in the transverse position, the welding process was stable without an aggregation of molten melt at the back surface. Moreover, the mechanisms of forming root sagging and humps were different at the top surface.
Thermodynamic Reassessment of the Na-Cu and Na-K Binary Systems
Authors: Trofimov Evgeny , Samoilova Olga , Zaitseva Olga , Vakhitova Elena
Published: August 2018

The Na-Cu and Na-K systems are of significant interest due to the use of liquid sodium and melt of sodium and potassium in the nuclear industry as a cooling agent in nuclear reactors. In the present work, thermodynamic modeling of phase equilibria in the Na-Cu and Na-K systems is carried out, based on the available published experimental data. This modeling was done using the “FactSage” software package (version 7.0). The set of Redlich-Kister equation parameters was obtained, which allows one to describe the dependence of Gibbs energy from composition and temperature for solutions that can be formed in the studied systems. Phase diagrams (T-x diagrams) of the investigated systems were calculated.
Effects of Electromagnetic Stirring on the Cast Austenitic Stainless Steel Weldments by Gas Tungsten Arc Welding
Authors: Jeng Sheng-Long , Su Dai-Ping , Lee Jing-Ting , Huang Jiunn-Yuan
Published: August 2018

Cast austenitic stainless steel (CASS) often contains high contents of silicon, phosphorus, and sulfur to prompt low melting phases to form in the welds. As a result, welding defects can be induced to degrade the welds. This study’s purpose was to investigate the effects of electromagnetic stirring (EMS) on the CASS weldments. The results showed that the ferrites in the heat affected zone (HAZ) had tortuous grain boundaries, while those that were close to the fusion lines had transformed austenites. EMS could reduce the influence of the welding heat to make the grain boundaries less tortuous and the transformed austenites smaller. Although their temperature profiles were almost the same, the gas-tungsten-arc-welding (GTAW) weld had smaller grains with massive ferrite colonies and more precipitates, while the GTAW+EMS weld had denser ferrite colonies with multi-orientations, but fewer precipitates. The hardness of the base metals and HAZs were typically higher than that of the welds. For both of the welds, the root was the region with the highest hardness. The hardness decreased from the root to the cap regions along the thickness direction. The GTAW weld had a higher hardness than the GTAW+EMS weld. At room temperature, the GTAW+EMS weld had a higher notched tensile strength and elongation than the GTAW weld. This could be attributed to the observation that the GTAW+EMS weld had dense and intersecting dendrites and that more austenites were deformed during tensile testing.
Modeling of Microstructure Evolution of Ti6Al4V for Additive Manufacturing
Authors: Salsi Emilio , Chiumenti Michele , Cervera Miguel
Published: August 2018

AM processes are characterized by complex thermal cycles that have a deep influence on the microstructural transformations of the deposited alloy. In this work, a general model for the prediction of microstructure evolution during solid state transformations of Ti6Al4V is presented. Several formulations have been developed and employed for modeling phase transformations in other manufacturing processes and, particularly, in casting. The proposed model is mainly based on the combination and modification of some of these existing formulations, leading to a new overall model specifically dedicated to AM. The accuracy and suitability of the integrated model is enhanced, introducing new dedicated features. In fact the model is designed to deal with fast cooling and re-heating cycles typical of AM processes because: (a) it is able to consider incomplete transformations and varying initial content of phases and (b) it can take into account simultaneous transformations.The model is implemented in COMET, an in-house Finite Element (FE)-based framework for the solution of thermo-mechanical engineering problems. The validation of the microstructural model is performed by comparing the simulation results with the data available in the literature. The sensitivity of the model to the variation of material parameters is also discussed.
Dynamic Disorder of Fe3+ Ions in the Crystal Structure of Natural Barioferrite
Authors: Krzątała Arkadiusz , Panikorovskii Taras L. , Galuskina Irina O. , Galuskin Evgeny V.
Published: August 2018

A natural barioferrite, BaFe3+12O19, from a larnite–schorlomite–gehlenite vein of paralava within gehlenite hornfels of the Hatrurim Complex at Har Parsa, Negev Desert, Israel, was investigated by Raman spectroscopy, electron probe microanalysis, and single-crystal X-ray analyses acquired over the temperature range of 100–400 K. The crystals are up to 0.3 mm × 0.1 mm in size and form intergrowths with hematite, magnesioferrite, khesinite, and harmunite. The empirical formula of the barioferrite investigated is as follows: (Ba0.85Ca0.12Sr0.03)∑1(Fe3+10.72Al0.46Ti4+0.41Mg0.15Cu2+0.09Ca0.08Zn0.04Mn2+0.03Si0.01)∑11.99O19. The strongest bands in the Raman spectrum are as follows: 712, 682, 617, 515, 406, and 328 cm−1. The structure of natural barioferrite (P63/mmc, a = 5.8901(2) Å, c = 23.1235(6) Å, V = 694.75(4) Å3, Z = 2) is identical with the structure of synthetic barium ferrite and can be described as an interstratification of two fundamental blocks: spinel-like S-modules with a cubic stacking sequence and R-modules that have hexagonal stacking. The displacement ellipsoids of the trigonal bipyramidal site show elongation along the [001] direction during heating. As a function of temperature, the mean apical Fe–O bond lengths increase, whereas the equatorial bond lengths decrease, which indicates dynamic disorder at the Fe2 site.