bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Waste Industrial Dust Safety Characteristics
Authors: Tureková Ivana , Mračková Eva , Marková Iveta
Published: June 2019

This article deals with the assessment of the hazards of dust waste generated by modern CNC (computer numerical control) technologies from the processing of resin-containing plastic composites. The change of the original material into dusty waste predicts the emergence of new hazardous characteristics such as flammability, explosiveness and adverse effects on employee health. The aim of this article is to determine the experimental measurement of dust particle size, its thermal degradation and safety characteristics. Sieve analysis showed that the representative sample contained a 93.8% weight of particles with a size of less than 0.4 mm. Three degrees of thermal degradation of industrial dust samples and heat production (exo reaction ∑ΔH = 9172.9 J/g) were determined by TG (thermogravimetry), DTA (differential thermal analysis) and DSC (differential scanning calorimetr) methods. The measurement safety characteristics such as the lower explosion limit, the maximum explosion pressure, the maximum pressure rise rate, and the calculated cubic constant confirmed that the dust is an explosive, and is determined as explosion class St1 (determined by Cubic constant).
Family Affluence Based Inequality in Oral Health-Related Quality of Life in a Population of Lithuanian Adolescents
Authors: Zaborskis Apolinaras , Kavaliauskienė Aistė , Šidlauskas Antanas
Published: June 2019

Background: The social inequalities in oral health have had increasing attention in recent years. The present study aimed to explore the impact of family affluence on Oral Health-Related Quality of Life (OHRQoL) among Lithuanian adolescents aged 11–18 years. Methods: The cross-sectional, population-based study included a representative sample of 881 adolescents aged 11–18 years (mean = 15.55; SD = 1.51) randomly selected from 20 schools in Lithuania. The schoolchildren completed questionnaires to evaluate their OHRQoL using a Lithuanian version of the Child Perceptions Questionnaire (CPQ). The adolescents’ family affluence was indirectly assessed by inquiring whether they possessed various modern life items. In dental examination, the severity of malocclusion was predetermined by the Index of Complexity, Outcome, and Need (ICON). The relationship among variables was examined employing the negative binomial regression and the path analysis. Results: The sum score of CPQ as a whole and the sum scores of all four domains were significantly associated with family affluence, indicating higher OHRQoL among adolescents from more affluent families. The severity of malocclusion had a significant association with emotional and social well-being domains of OHRQoL only. Conclusion: This study evidences the family affluence based inequality in OHRQoL among Lithuanian adolescents.
Prevalence of Leptospira Infection in Rodents from Bangladesh
Authors: Krijger Inge M. , Ahmed Ahmed A. A. , Goris Marga G. A. , Groot Koerkamp Peter W. G. , Meerburg Bastiaan G.
Published: June 2019

Worldwide, Leptospira infection poses an increasing public health problem. In 2008, leptospirosis was recognised as a re-emerging zoonosis of global importance with South-East Asia being one of the most significant centres of the disease. Rodents are thought to be the most important host for a variety of Leptospira serovars. Because Bangladesh offers a suitable humid climate for the survival of these pathogenic bacteria, the presence of rodents could be a serious risk for human infection, especially in peri-urban areas or locations where food is stored. In order to gain more understanding of the multi-host epidemiology, a prevalence study was conducted in Comilla, Bangladesh to determine the presence of pathogenic Leptospira species in rodents. Real-time Polymerase Chain Reaction (qPCR) and sequencing showed that 13.1% (61/465) of the trapped rodents were infected with pathogenic Leptospira. Sequencing of the qPCR products identified the presence of three species: Leptospira interrogans, Leptospira borgpetersenii, and Leptospira kirschneri. Rodents of the genus, Bandicota, were significantly more likely to be positive than those of the genus, Rattus and Mus. Our results confirm the importance of rodents as hosts of pathogenic Leptospira and indicate that human exposure to pathogenic Leptospira may be considerable, also in places where food (rice) is stored for longer times. This study emphasizes the need to improve rodent management at such locations and to further quantify the public health impacts of this neglected emerging zoonosis in Bangladesh.
Association between Household Food Insecurity and Asthma in Korean Adults
Authors: Park Seo-Hee , Park Byung-Jin , Jung Dong-Hyuk , Kwon Yu-Jin
Published: June 2019

Household food insecurity has been associated with noncommunicable diseases. The aim of this study was to investigate the association between household food insecurity and asthma in Korean adults. Household food security statuses were classified into three groups: Food-secure household, food-insecure household without hunger, and food-insecure household with hunger. The odds ratios and 95% confidence intervals for the presence of asthma according to household food security status were calculated using multiple logistic regression analyses after adjusting for confounding factors. A total of 14,770 participants were included in the analysis. The prevalence of asthma was 2.6% in those with a secure food status, 3.2% in those with an insecure food status without hunger, and 7.6% in those with an insecure food status with hunger (p < 0.001). Compared with that in participants with a household food secure status, the odds ratios (95% confidence intervals) for asthma were 1.12 (0.73–1.73) in those with a food-insecure household without hunger status and 2.44 (1.33–4.46) in those with a food-insecure household with hunger status after additionally adjusting for confounding factors. We found that household food insecurity with hunger was significantly associated with asthma prevalence in Korean adults. Implementation of household food security screening and public health intervention could be helpful to prevent and reduce asthma in adults.
The Search for Environmental Justice: The Story of North Birmingham
Authors: Allen Shauntice , Fanucchi Michelle V. , McCormick Lisa C. , Zierold Kristina M.
Published: June 2019

Environmental justice is a rising social movement throughout the world. Research is beginning to define the movement and address the disparities that exist among communities exposed to pollution. North Birmingham, a community made up of six neighborhoods in Jefferson County, Alabama, in the United States, is a story of environmental injustice. Heavy industry, including the 35th Avenue Superfund Site, has caused significant environmental pollution over time, leaving residents concerned that their health and well-being are at risk from continued exposure. For years, pollution has impacted the community, and residents have fought and challenged industry and government. The United States (U.S.) Environmental Protection Agency (EPA), the U.S. Agency for Toxic Substances and Disease Registry (ATSDR), and the Jefferson County Department of Health (JCDH) in Alabama have historically played a role in working with the community regarding their health concerns. In this manuscript, we describe a city entrenched in environmental injustice. We provide the history of the community, the responsible parties named for the contamination, the government’s involvement, and the community’s response to this injustice. Through this manuscript, we offer insight into a global concern that challenges local communities on a daily basis.
Mechanisms of Adiponectin Action
Authors: Fiaschi Tania
Published: June 2019

Adiponectin, the most abundant secreted adipokine, has received great attention from the scientific community since its discovery [...]
Bone Matrix Levels of Dickkopf and Sclerostin are Positively Correlated with Bone Mass and Strength in Postmenopausal Osteoporosis
Authors: Ueland Thor , Stilgren Lis , Bollerslev Jens
Published: June 2019

Wnt signaling plays a pivotal role in maintaining bone mass. Secreted pathway modulators such as sclerostin (SOST) and Dickkopfs (DKKs) may influence bone mass inhibiting the canonical Wnt pathway. We evaluated whether bone protein content of secreted Wnt antagonists is related to age, bone mass, and strength in postmenopausal osteoporosis. We measured cortical and trabecular bone contents of SOST and Dickkopf-1 (DKK1) in combined extracts obtained after ethylenediaminetetraacetic acid and guanidine hydrochloride extraction in 56 postmenopausal women aged 47–74 (mean, 63) yr with a previous distal forearm fracture and a hip or spine Z-score less than 0. Our findings were (i) SOST and DKK1 protein levels were higher in trabecular bone, (ii) cortical and trabecular DKK1 and trabecular SOST correlated positively with bone matrix levels of osteocalcin (r between 0.28 and 0.45, p < 0.05), (iii) cortical DKK1 correlated with lumbar spine bone mineral density (BMD) (r = 0.32, p < 0.05) and femoral neck BMD (r = 0.41, p < 0.01), and (iv) cortical DKK1 and SOST correlated with apparent bone volumetric density and compressive strength (r between 0.34 and 0.51, p < 0.01). In conclusion, cortical bone matrix levels of DKK1 and SOST were positively correlated with bone mass and bone strength in postmenopausal osteoporotic women.
Role of Leukotriene B4 Receptor-2 in Mast Cells in Allergic Airway Inflammation
Authors: Kwon Sun-Young , Kim Jae-Hong
Published: June 2019

Mast cells are effector cells in the immune system that play an important role in the allergic airway inflammation. Recently, it was reported that BLT2, a low-affinity leukotriene (LT) B4 receptor, plays a pivotal role in the pathogenesis of allergic airway inflammation through its action in mast cells. We observed that highly elevated expression levels of BLT2 are critical for the pathogenesis leading to allergic airway inflammation, and that if BLT2 expression is downregulated by siBLT2-mediated knockdown, allergic inflammation is dramatically alleviated. Furthermore, we demonstrated that BLT2 mediates the synthesis of vascular endothelial growth factor (VEGF) and Th2 cytokines, such as interleukin (IL)-13, in mast cells during allergic inflammation. Based on the critical roles of BLT2 in mast cells in allergic inflammation, anti-BLT2 strategies could contribute to the development of new therapies for allergic airway inflammation.
A Novel Reporter Mouse Uncovers Endogenous Brn3b Expression
Authors: Miltner Adam M. , Mercado-Ayon Yesica , Cheema Simranjeet K. , Zhang Pengfei , Zawadzki Robert J. , La Torre Anna
Published: June 2019

Brn3b (Pou4f2) is a class-4 POU domain transcription factor known to play central roles in the development of different neuronal populations of the Central Nervous System, including retinal ganglion cells (RGCs), the neurons that connect the retina with the visual centers of the brain. Here, we have used CRISPR-based genetic engineering to generate a Brn3b-mCherry reporter mouse without altering the endogenous expression of Brn3b. In our mouse line, mCherry faithfully recapitulates normal Brn3b expression in the retina, the optic tracts, the midbrain tectum, and the trigeminal ganglia. The high sensitivity of mCherry also revealed novel expression of Brn3b in the neuroectodermal cells of the optic stalk during early stages of eye development. Importantly, the fluorescent intensity of Brn3b-mCherry in our reporter mice allows for noninvasive live imaging of RGCs using Scanning Laser Ophthalmoscopy (SLO), providing a novel tool for longitudinal monitoring of RGCs.
Dietary Supplementation with Sea Bass (Lateolabrax maculatus) Ameliorates Ulcerative Colitis and Inflammation in Macrophages through Inhibiting Toll-Like Receptor 4-Linked Pathways
Authors: Chen Jiali , Jayachandran Muthukumaran , Zhang Wenxia , Chen Lingyuqing , Du Bin , Yu Zhiling , Xu Baojun
Published: June 2019

Sea bass (Lateolabrax maculatus) is a kind of food material commonly consumed in daily life. In traditional Chinese medicinal books, it has been indicated that sea bass can be applied for managing many inflammation-associated conditions. However, the studies on the pharmacological mechanisms of inflammation of sea bass remain scarce. Hence, this study aims to investigate the molecular mechanisms of the anti-inflammatory activity of sea bass. Anti-inflammatory activities of sea bass were assessed using dextran sulfate sodium (DSS)-induced colitis in a mice model and lipopolysaccharide (LPS)-activated macrophages model. Low body weight and short colon length were observed in DSS-fed mice that were significantly recovered upon sea bass treatments. Moreover, the colon histopathology score showed that sea bass-treated mice had decreased crypt damage, focal inflammation infiltration and the extent of inflammation, suggesting that treatment with sea bass could attenuate intestinal inflammation. In addition, the in-vitro study conjointly indicated that sea bass could suppress the inflammatory mediators in LPS-activated macrophage by inhibiting the TLR4-linked pathway. The present findings demonstrated that sea bass has an inhibitory effect on TLR4 signaling; thus, it could be a promising candidate for treating inflammation-associated conditions. A further justification for the clinical application of sea bass in treating inflammation-associated conditions is necessary.
Biocontrol and Action Mechanism of Bacillus amyloliquefaciens and Bacillus subtilis in Soybean Phytophthora Blight
Authors: Liu Dong , Li Kunyuan , Hu Jiulong , Wang Weiyan , Liu Xiao , Gao Zhimou
Published: June 2019

With the improper application of fungicides, Phytophthora sojae begins to develop resistance to fungicides, and biological control is one of the potential ways to control it. We screened two strains of Bacillus; Bacillus amyloliquefaciens JDF3 and Bacillus subtilis RSS-1, which had an efficient inhibitory effect on P. sojae. They could inhibit mycelial growth, the germination of the cysts, and the swimming of the motile zoospores. To elucidate the response of P. sojae under the stress of B. amyloliquefaciens and B. subtilis, and the molecular mechanism of biological control, comparative transcriptome analysis was applied. Transcriptome analysis revealed that the expression gene of P. sojae showed significant changes, and a total of 1616 differentially expressed genes (DEGs) were detected. They participated in two major types of regulation, namely “specificity” regulation and “common” regulation. They might inhibit the growth of P. sojae mainly by inhibiting the activity of ribosome. A pot experiment indicated that B. amyloliquefaciens and B. subtilis enhanced the resistance of soybean to P. sojae, and their control effects of them were 70.7% and 65.5%, respectively. In addition, B. amyloliquefaciens fermentation broth could induce an active oxygen burst, NO production, callose deposition, and lignification. B. subtilis could also stimulate the systemic to develop the resistance of soybean by lignification, and phytoalexin.
Cell-Free, Embryo-Specific sncRNA as a Molecular Biological Bridge between Patient Fertility and IVF Efficiency
Authors: Timofeeva Angelika V. , Chagovets Vitaliy V. , Drapkina Yulia S. , Makarova Nataliya P. , Kalinina Elena A. , Sukhikh Gennady T.
Published: June 2019

Small noncoding RNAs (sncRNAs) are key regulators of the majority of human reproduction events. Understanding their function in the context of gametogenesis and embryogenesis will allow insight into the possible causes of in vitro fertilization (IVF) implantation failure. The aim of this study was to analyze the sncRNA expression profile of the spent culture media on day 4 after fertilization and to reveal a relationship with the morphofunctional characteristics of gametes and resultant embryos, in particular, with the embryo development and implantation potential. Thereto, cell-free, embryo-specific sncRNAs were identified by next generation sequencing (NGS) and quantified by reverse transcription coupled with polymerase chain reaction (RT-PCR) in real-time. Significant differences in the expression level of let-7b-5p, let-7i-5p, piR020401, piR16735, piR19675, piR20326, and piR17716 were revealed between embryo groups of various morphological gradings. Statistically significant correlations were found between the expression profiles of piR16735 and piR020401 with the oocyte-cumulus complex number, let-7b-5p and piR020401 with metaphase II oocyte and two pronuclei embryo numbers, let-7i-5p and piR20497 with the spermatozoid count per milliliter of ejaculate, piR19675 with the percentage of linearly motile spermatozoids, let-7b-5p with the embryo development grade, and let-7i-5p with embryo implantation. According to partial least squares discriminant analysis (PLS-DA), the expression levels of let-7i-5p (Variable Importance in Projection score (VIP) = 1.6262), piR020401 (VIP = 1.45281), and piR20497 (VIP = 1.42765) have the strongest influences on the implantation outcome.
Mechanisms Underlying Spontaneous Action Potential Generation Induced by Catecholamine in Pulmonary Vein Cardiomyocytes: A Simulation Study
Authors: Umehara Shohei , Tan Xiaoqiu , Okamoto Yosuke , Ono Kyoichi , Noma Akinori , Amano Akira , Himeno Yukiko
Published: June 2019

Cardiomyocytes and myocardial sleeves dissociated from pulmonary veins (PVs) potentially generate ectopic automaticity in response to noradrenaline (NA), and thereby trigger atrial fibrillation. We developed a mathematical model of rat PV cardiomyocytes (PVC) based on experimental data that incorporates the microscopic framework of the local control theory of Ca2+ release from the sarcoplasmic reticulum (SR), which can generate rhythmic Ca2+ release (limit cycle revealed by the bifurcation analysis) when total Ca2+ within the cell increased. Ca2+ overload in SR increased resting Ca2+ efflux through the type II inositol 1,4,5-trisphosphate (IP3) receptors (InsP3R) as well as ryanodine receptors (RyRs), which finally triggered massive Ca2+ release through activation of RyRs via local Ca2+ accumulation in the vicinity of RyRs. The new PVC model exhibited a resting potential of −68 mV. Under NA effects, repetitive Ca2+ release from SR triggered spontaneous action potentials (APs) by evoking transient depolarizations (TDs) through Na+/Ca2+ exchanger (APTDs). Marked and variable latencies initiating APTDs could be explained by the time courses of the α1- and β1-adrenergic influence on the regulation of intracellular Ca2+ content and random occurrences of spontaneous TD activating the first APTD. Positive and negative feedback relations were clarified under APTD generation.
Dynamics of an Ongoing Wolbachia Spread in the European Cherry Fruit Fly, Rhagoletis cerasi (Diptera: Tephritidae)
Authors: Schebeck Martin , Feldkirchner Lukas , Stauffer Christian , Schuler Hannes
Published: June 2019

Numerous terrestrial arthropods are infected with the alphaproteobacterium Wolbachia. This endosymbiont is usually transmitted vertically from infected females to their offspring and can alter the reproduction of hosts through various manipulations, like cytoplasmic incompatibility (CI), enhancing its spread in new host populations. Studies on the spatial and temporal dynamics of Wolbachia under natural conditions are scarce. Here, we analyzed Wolbachia infection frequencies in populations of the European cherry fruit fly, Rhagoletis cerasi (L.), in central Germany—an area of an ongoing spread of the CI-inducing strain wCer2. In total, 295 individuals from 19 populations were PCR-screened for the presence of wCer2 and their mitochondrial haplotype. Results were compared with historic data to understand the infection dynamics of the ongoing wCer2 invasion. An overall wCer2 infection frequency of about 30% was found, ranging from 0% to 100% per population. In contrast to an expected smooth transition from wCer2-infected to completely wCer2-uninfected populations, a relatively scattered infection pattern across geography was observed. Moreover, a strong Wolbachia-haplotype association was detected, with only a few rare misassociations. Our results show a complex dynamic of an ongoing Wolbachia spread in natural field populations of R. cerasi.
Effect of Short Term Intensive Lifestyle Intervention on Hepatic Steatosis Indexes in Adults with Obesity and/or Type 2 Diabetes
Authors: Reginato Elisa , Pippi Roberto , Aiello Cristina , Sbroma Tomaro Emilia , Ranucci Claudia , Buratta Livia , Bini Vittorio , Marchesini Giulio , De Feo Pierpaolo , Fanelli Carmine
Published: June 2019

Background: Non-alcoholic fatty liver disease (NAFLD) has an estimated prevalence of 20–30% in the general population and even higher in individuals with metabolic risk factors. The aim of this study was to evaluate the effect of a lifestyle intervention program on surrogate markers of hepatic steatosis in obesity and/or type 2 diabetes patients, enrolled in the C.U.R.I.A.Mo. (Centro Universitario di Ricerca Interdipartimentale Attività Motoria) trial. Methods: 102 subjects (56 females and 46 males, aged between 23 and 78) with type 2 diabetes, obesity or a BMI of at least 25 kg/m2 with comorbidities, participated in the intensive phase of a multidisciplinary lifestyle intervention program at the Healthy Lifestyle Institute of the University of Perugia (C.U.R.I.A.Mo.). Six indices related to NAFLD (Visceral Adiposity Index, Fatty Liver index, Non-Alcoholic Fatty Liver Disease liver fat score and liver fat equation, hepatic steatosis index and TyG index) were calculated before and after a three-month multidisciplinary lifestyle intervention. Results: The intervention improved the anthropometric and clinical parameters in the total population, the obese and/or diabetics. Data showed a significant weight loss, a reduced waist circumference, triglycerides, and an improvement in Mediterranean diet adherence. Hepatic steatosis indices were significantly reduced in the total population and in different subgroups (males, females, obesity and diabetes).
HDL and LDL: Potential New Players in Breast Cancer Development
Authors: Cedó Lídia , Reddy Srinivasa T. , Mato Eugènia , Blanco-Vaca Francisco , Escolà-Gil Joan Carles
Published: June 2019

Breast cancer is the most prevalent cancer and primary cause of cancer-related mortality in women. The identification of risk factors can improve prevention of cancer, and obesity and hypercholesterolemia represent potentially modifiable breast cancer risk factors. In the present work, we review the progress to date in research on the potential role of the main cholesterol transporters, low-density and high-density lipoproteins (LDL and HDL), on breast cancer development. Although some studies have failed to find associations between lipoproteins and breast cancer, some large clinical studies have demonstrated a direct association between LDL cholesterol levels and breast cancer risk and an inverse association between HDL cholesterol and breast cancer risk. Research in breast cancer cells and experimental mouse models of breast cancer have demonstrated an important role for cholesterol and its transporters in breast cancer development. Instead of cholesterol, the cholesterol metabolite 27-hydroxycholesterol induces the proliferation of estrogen receptor-positive breast cancer cells and facilitates metastasis. Oxidative modification of the lipoproteins and HDL glycation activate different inflammation-related pathways, thereby enhancing cell proliferation and migration and inhibiting apoptosis. Cholesterol-lowering drugs and apolipoprotein A-I mimetics have emerged as potential therapeutic agents to prevent the deleterious effects of high cholesterol in breast cancer.
Microstructure Development during Low-Current Resistance Spot Welding of Aluminum to Magnesium
Authors: Cooke Kavian O. , Khan Tahir I.
Published: June 2019

Resistance spot welding of aluminum (Al5754) to magnesium (AZ31B) alloys results in the formation of a variety of solidification microstructures and intermetallic compounds that may affect the in-service performance of the weld. This study evaluates the relationship between the welding parameters and the properties of the weld nugget that is formed, and clarifies the morphological and microstructural evolutions within the weld regions during the low-current “small-scale” resistance spot welding of Al5754 to AZ31B. The investigations included a combination of microstructural characterization and thermodynamic analysis of the weld region. The results show that the welding time and clamping force parameters have significant effects on the properties of the nugget formed. The optimal welding parameters were found to be 300 ms welding time and 800 N clamping force. Weld nuggets formed with lower welding time and clamping force were undersized and contained extensive porosity. Meanwhile, a clamping force above 800 N caused gross deformation of the test samples and the expulsion of the molten metal during the welding process. The most significant microstructural changes occurred at the weld/base metal interfaces due to the formation of Al17Mg12 and MgAl2O4 intermetallic compounds as well as significant compositional variation across the weld pool. The thermal gradient across the weld pool facilitated the formation of several microstructural transitions between equiaxed and columnar dendrites.
On the Relationship of the Degrees of Correspondence of Dialects and Distances
Authors: Onishi Takuichiro
Published: June 2019

This study analyzes the relationship between the degrees of resemblance and distances between dialects based on several dialectological atlases. This analysis investigates various correspondence data with respect to total valid data in setting reference places and comparison places. The degree of correspondence (DC) can be calculated by quantifying the degree of resemblance. I adopt a great-circular distance for the distance between the source and a comparison place. It is possible to graph the data with distances and DCs along the X and Y axes, respectively. The analysis yields five main results. (1) DC has an inverse relationship with distance in most places, here called the main sequence. However, there are exceptional places called peculiar groups. (2) One of the peculiar groups was caused by in-migration. (3) Another peculiar group is found on islands having very narrow land areas divided by the sea. (4) The main sequence can be classified into two types of linguistic classes. The grammatical data show a stepping slope instead of a gentle slope in the lexical data. (5) The main sequence shows a precise linear relationship over a narrow area.
Effects of Cooling Rate on the Solidification and Microstructure of Nickel-Based Superalloy GTD222
Authors: Gao Bo , Sui Yanfei , Wang Hongwei , Zou Chunming , Wei Zunjie , Wang Rui , Sun Yanle
Published: June 2019

In this work, the microstructure and solidification behavior of nickel-based superalloy GTD222 at different cooling rates are studied. The solidification of the superalloy GTD222 proceeds as follows: L → L + γ, L → L + γ + MC, L → L + (γ/γ′)-Eutectic and L → η phase. Due to alloying element redistribution, the temperature of the solidus GTD222 superalloy, 1310 °C, is slightly lower than the temperature of the liquidus, which is 1360 °C. It was found that the dendrite arm spacing of the alloy decreased with the increase of the cooling rate from 200 μm at 2.5 K/min to 100 μm at 20 K/min.
Effect of Irrigants on the Push-Out Bond Strength of Two Bioceramic Root Repair Materials
Authors: Alamoudi Ruaa A. , Abu Zeid Sawsan T.
Published: June 2019

The purpose of this study was to compare different irrigants’ effect on two EndoSequence root repair materials’ push-out bond strength. Sixty root slices were filled either with EndoSequence premixed fast-set putty or regular-set paste, and then immersed either in sodium hypochlorite, chlorhexidine gluconate, or saline (as control) for 30 min, after which the slices were subjected to the push-out test. The surface structures were evaluated with Scanning Electron Microscopy and Fourier Transform Infrared. Fast-set putty exhibited greater displacement resistance when immersed in saline and subjected to adhesive failure mode, while regular-set paste showed greater resistance when immersed in chlorhexidine and subjected to cohesive failure mode. Infrared analysis showed changes in organic filler, and carbonate and phosphate bands after using irrigants. The lowest carbonate/phosphate ratio was found for chlorhexidine in both materials. Therefore, sodium hypochlorite reduced EndoSequence root repair materials’ displacement resistance markedly.
The Utilization of Recycled Masonry Aggregate and Recycled EPS for Concrete Blocks for Mortarless Masonry
Authors: Pavlu Tereza , Fortova Kristina , Divis Jakub , Hajek Petr
Published: June 2019

The main aim of this paper is to carry out the environmentally based enhancement of a concrete mixture containing recycled materials whilst considering natural resource consumption as well as mechanical and thermal property levels. The developed concrete is intended to be used in mortarless masonry wall structures. Ten concrete mixtures with different types and replacement rates of recycled masonry aggregate and recycled expanded polystyrene were prepared, and their mechanical and thermal properties were experimentally investigated. It was found that the use of recycled masonry aggregate led to better thermal properties while maintaining sufficient mechanical properties. On the contrary, the addition of recycled expanded polystyrene did not significantly affect the thermal properties of concrete, but the mechanical properties considerably declined. For this reason, the recycled masonry aggregate is suitable to use as an aggregate for concrete masonry blocks for wall structures.
Drug Release Kinetics of Electrospun PHB Meshes
Authors: Kundrat Vojtech , Cernekova Nicole , Kovalcik Adriana , Enev Vojtech , Marova Ivana
Published: June 2019

Microbial poly(3-hydroxybutyrate) (PHB) has several advantages including its biocompatibility and ability to degrade in vivo and in vitro without toxic substances. This paper investigates the feasibility of electrospun PHB meshes serving as drug delivery systems. The morphology of the electrospun samples was modified by varying the concentration of PHB in solution and the solvent composition. Scanning electron microscopy of the electrospun PHB scaffolds revealed the formation of different morphologies including porous, filamentous/beaded and fiber structures. Levofloxacin was used as the model drug for incorporation into PHB electrospun meshes. The entrapment efficiency was found to be dependent on the viscosity of the PHB solution used for electrospinning and ranged from 14.4–81.8%. The incorporation of levofloxacin in electrospun meshes was confirmed by Fourier-transform infrared spectroscopy and UV-VIS spectroscopy. The effect of the morphology of the electrospun meshes on the levofloxacin release profile was screened in vitro in phosphate-buffered saline solution. Depending upon the morphology, the electrospun meshes released about 14–20% of levofloxacin during the first 24 h. The percentage of drug released after 13 days increased up to 32.4% and was similar for all tested morphologies. The antimicrobial efficiency of all tested samples independent of the morphology, was confirmed by agar diffusion testing.
Structural and Electrical Characterization of 2” Ammonothermal Free-Standing GaN Wafers. Progress toward Pilot Production
Authors: Key Daryl , Letts Edward , Tsou Chuan-Wei , Ji Mi-Hee , Bakhtiary-Noodeh Marzieh , Detchprohm Theeradetch , Shen Shyh-Chiang , Dupuis Russell , Hashimoto Tadao
Published: June 2019

Free-standing gallium nitride (GaN) substrates are in high demand for power devices, laser diodes, and high-power light emitting diodes (LEDs). SixPoint Materials Inc. has begun producing 2” GaN substrates through our proprietary Near Equilibrium AmmonoThermal (NEAT) growth technology. In a single 90 day growth, eleven c-plane GaN boules were grown from free-standing hydride vapor phase epitaxy (HVPE) GaN substrates. The boules had an average X-ray rocking curve full width at half maximum (FWHM) of 33 ± 4 in the 002 reflection and 44 ± 6 in the 201 reflection using 0.3 mm divergence slits. The boules had an average radius of curvature of 10.16 ± 3.63 m. The quality of the boules was highly correlated to the quality of the seeds. A PIN diode grown at Georgia Tech on a NEAT GaN substrate had an ideality factor of 2.08, a high breakdown voltage of 1430 V, and Baliga’s Figure of Merit of >9.2 GW/cm2. These initial results demonstrate the suitability of using NEAT GaN substrates for high-quality MOCVD growth and fabrication of high-power vertical GaN switching devices.
Unmanned Ground Vehicle Modelling in Gazebo/ROS-Based Environments
Authors: Rivera Zandra B. , De Simone Marco C. , Guida Domenico
Published: June 2019

The fusion of different technologies is the base of the fourth industrial revolution. Companies are encouraged to integrate new tools in their production processes in order to improve working conditions and increase productivity and production quality. The integration between information, communication technologies and industrial automation can create highly flexible production models for products and services that can be customized through real-time interactions between consumer, production and machinery throughout the production process. The future of production, therefore, depends on increasingly intelligent machinery through the use of digital systems. The key elements for future integrated devices are intelligent systems and machines, based on human–machine interaction and information sharing. To do so, the implementation of shared languages that allow different systems to dialogue in a simple way is necessary. In this perspective, the use of advanced prototyping tools like Open-Source programming systems, the development of more detailed multibody models through the use of CAD software and the use of self-learning techniques will allow for developing a new class of machines capable of revolutionizing our companies. The purpose of this paper is to present a waypoint navigation activity of a custom Wheeled Mobile Robot (WMR) in an available simulated 3D indoor environment by using the Gazebo simulator. Gazebo was developed in 2002 at the University of Southern California. The idea was to create a high-fidelity simulator that gave the possibility to simulate robots in outdoor environments under various conditions. In particular, we wanted to test the high-performance physics Open Dynamics Engine (ODE) and the sensors feature present in Gazebo for prototype development activities. This choice was made for the possibility of emulating not only the system under analysis, but also the world in which the robot will operate. Furthermore, the integration tools available with Solidworks and Matlab-Simulink, well known commercial platforms of modelling and robotics control respectively, are also explored.
Ulva lactuca, A Source of Troubles and Potential Riches
Authors: Dominguez Herminia , Loret Erwann P.
Published: June 2019

Ulva lactuca is a green macro alga involved in devastating green tides observed worldwide. These green tides or blooms are a consequence of human activities. Ulva blooms occur mainly in shallow waters and the decomposition of this alga can produce dangerous vapors. Ulva lactuca is a species usually resembling lettuce, but genetic analyses demonstrated that other green algae with tubular phenotypes were U. lactuca clades although previously described as different species or even genera. The capacity for U. lactuca to adopt different phenotypes can be due to environment parameters, such as the degree of water salinity or symbiosis with bacteria. No efficient ways have been discovered to control these green tides, but the Mediterranean seas appear to be protected from blooms, which disappear rapidly in springtime. Ulva contains commercially valuable components, such as bioactive compounds, food or biofuel. The biomass due to this alga collected on beaches every year is beginning to be valorized to produce valuable compounds. This review describes different processes and strategies developed to extract these different valuable components.
Tissue Oxygen Saturation Change on Upper Extremities After Ultrasound-Guided Infraclavicular Brachial Plexus Blockade; Prospective Observational Study
Authors: Karahan Mahmut Alp , Binici Orhan , Büyükfırat Evren
Published: June 2019

Background and Objective: The aim of this study was to investigate whether tissue oxygen saturation (StO2) is a reliable and objective method for assessing the adequacy of infraclavicular block and to describe the time course of StO2 changes. Materials and Methods: In this prospective observational study, StO2 was measured in 40 patients planned for elective hand surgery under infraclavicular block. Noninvasive StO2 monitoring was used prior to ultrasound-guided infraclavicular brachial plexus block and during the first 30 min of the blockade. Sensory and motor blocks were evaluated every 5 min followed by pinprick testing and Bromage scale. Results: Preanesthetic median StO2 values of the blocked side and nonblocked side were similar (p = 0.532), whereas the postanesthetic values of the blocked side were higher. At the fifth minute and the following minute, measurements compared to the nonblocked side (p < 0.001). The median StO2 values increased significantly, which increased by 4.5% at 5 min, by another 5.5% at 30 min, and by an average of 1% from 5 to 30 min compared to the baseline values in the blocked side. The responses of the patients to the questions probed in the pinprick test and Bromage scale were fully compatible with the data obtained by the near-infrared spectroscopy (NIRS) method. Conclusions: StO2 monitoring may provide a useful instrument for rapid evaluation of the success of regional anesthesia in the upper extremity.
An Investigation of Oxidative Stress and Thiol/Disulphide Homeostasis in Graves’ Disease
Authors: Agan Veysel , Celik Hakim , Eren Mehmet Ali , Agan Fatma Zehra , Erel Ozcan , Neselioglu Salim , Koyuncu Ismail , Gonel Ataman
Published: June 2019

Background and objectives: The aim of this study was to research oxidative stress and thiol/disulphide homeostasis in Graves’ patients. Materials and Methods: The study included 33 Graves’ patients (research group) and 35 healthy subjects (control group). Serum oxidative stress and thiol/disulphide homeostasis (a new and automated spectrophotometric method developed by Erel and Neselioglu) parameters were studied and compared between the groups. Results: The native and total thiol levels and the native thiol/total thiol ratio were lower in patients with Graves’ disease compared to the control group (p < 0.001, p < 0.001, and p = 0.006, respectively). TOS (total antioxidant status), PC (protein carbonyl), OSI (Oxidative stress index), and disulphide/native thiol and disulphide/total thiol ratios were determined to be higher in the Graves’ disease group than in the control group (p < 0.001, p = 0.001, p = 0.001, p = 0.004, and p = 0.006, respectively). In the Graves’ disease group, the free triiodothyronine (FT3) and free thyroxine (FT4) levels were significantly positively correlated with impaired thiol/disulphide homeostasis and oxidative stress parameters (p < 0.05). Conclusion: The results of the current study demonstrated that oxidative stress and thiol/disulphide homeostasis increased towards disulphide formation due to thiol oxidation in Graves’ disease. In addition, a positive correlation of FT3 and FT4 was observed with oxidative stress parameters and impaired thiol/disulphide homeostasis.
Gas Permeation of Sulfur Thin-Films and Potential as a Barrier Material
Authors: Jia Xicheng , Bennett Thomas D. , Cowan Matthew G.
Published: June 2019

Elemental sulfur was formed into poly(ether sulfone)-supported thin-films (ca. 10 µm) via a melt-casting process. Observed permeabilities of C2H4, CO2, H2, He, and N2 through the sulphur thin-films were <1 barrer. The sulfur thin-films were observed to age over a period of ca. 15 days, related to the reversion of polymerized sulfur to the S8 allotrope. This structural conversion was observed to correlate with an increase in the permeability of all gases.
The Path to Type-II Superconductivity
Authors: Huebener Rudolf P.
Published: June 2019

Following the discovery of superconductivity by Heike Kamerlingh Onnes in 1911, research concentrated on the electric conductivity of the materials investigated. Then, it was Max von Laue who in the early 1930s turned his attention to the magnetic properties of superconductors, such as their demagnetizing effects in a weak magnetic field. As a consultant at the Physikalisch-Technische Reichsanstalt in Berlin, von Laue was in close contact with Walther Meissner at the Reichsanstalt. In 1933, Meisner together with Robert Ochsenfeld discovered the perfect diamagnetism of superconductors (Meissner–Ochsenfeld effect). This was a turning point, indicating that superconductivity represents a thermodynamic equilibrium state and leading to the London theory and the Ginzburg–Landau theory. In the early 1950s in Moscow, Nikolay Zavaritzkii carried out experiments on superconducting thin films. In the theoretical analysis of his experiments, he collaborated with Alexei A. Abrikosov and for the first time they considered the possibility that the coherence length ξ can be smaller than the magnetic penetration depth λ m . They called these materials the “second group”. Subsequently, Abrikosov discovered the famous Abrikosov vortex lattice and the superconducting mixed state. The important new field of type-II superconductivity was born.
Effect of Electron Beam Method on Processing of Titanium Technogenic Material
Authors: Vutova Katia , Vassileva Vania , Stefanova Vladislava , Amalnerkar Dinesh , Tanaka Takeshi
Published: June 2019

This study reveals the efficiency of the electron beam processing of titanium technogenic material with a high level of impurities and the quality of the obtained metal in correlation to process parameters which are discussed. The influence of the beam power and melting time on the composition variation, morphologies, hardness of metal samples and mass losses is investigated. Based on the different technological parameters, the removal efficiency of impurities is also discussed, and the corresponding experiments are carried out in order to make a comparison. Different thermal process conditions are realized during the single-melt operation. Chemical and metallographic analyses are performed, and the results are discussed. The hardness of the titanium decreases by prolonging the time of the electron beam processing. A maximal overall removal efficiency of 99.975% is seen at 5.5 kW beam power for a 40 min melting time and the best purification of Ti (99.996%) is achieved.
Effect of Microstructure and Texture on Mechanical Properties of Resistance Spot Welded High Strength Steel 22MnB5 and 5A06 Aluminium Alloy
Authors: Jiang Xiaoqing , Chen Shujun , Gong Jinlong , Lu Zhenyang
Published: June 2019

The present study aims to investigate the effect of microstructure and texture on mechanical properties of resistance spot welding of high strength steel 22MnB5 and 5A06 aluminium alloy as a function of welding parameters. The pseudo-nugget zones (NZs) at the steel side have undergone full recrystallisation with a fine-grained ferrite structure containing a small amount of retained austenite and a high hardness of approximately 500 HV, which is a 35% increase in hardness compared to the base material (BM) with fine lath martensitic structure. The NZs at the Al side contain both a recrystallisation texture and shear texture. Higher tensile shear strength with increasing weld time could be linked to the random texture at the Al side. The highest tensile shear strength was achieved at an intermetallic layer thickness of 4 mm.
Design of Rigidity and Breaking Strain for a Kirigami Structure with Non-Uniform Deformed Regions
Authors: Taniyama Hiroki , Iwase Eiji
Published: June 2019

We modeled a kirigami structure by considering the influence of non-uniform deforming cuts in order to theoretically design the mechanical characteristics of the structure. It is known that the end regions of kirigami structures are non-uniformly deformed when stretched, because the deformation is inhibited at the regions close to both the ends connected to the uncut region in the longitudinal direction. The non-uniform deformation affects the overall mechanical characteristics of the structure. Our model was intended to elucidate how cuts at both ends influence these characteristics. We focused on the difference in the deformation degree caused by a cut between the regions close to the ends and the center of the stretched kirigami device. We proposed a model comprising of connected springs in series with different rigidities in the regions close to the ends and the center. The spring model showed good prediction tendency with regard to the curve of the stress–strain diagram obtained using the tensile test with a test piece. Therefore, the results show that it is possible to theoretically design the mechanical characteristics of a kirigami structure, and that such a design can well predict the influence of cuts, which induce non-uniform deformation at both ends.
Chaotic Micromixer Based on 3D Horseshoe Transformation
Authors: Zhang He , Li Xin , Chuai Rongyan , Zhang Yingjie
Published: June 2019

To improve the efficiency of mixing under laminar flow with a low Reynolds number (Re), a novel three-dimensional Horseshoe Transformation (3D HT) was proposed as the basis for the design of a micromixer. Compared with the classical HT, the Lyapunov exponent of the 3D HT, which was calculated based on a symbolic dynamic system, proved the chaotic enhancement. Based on the 3D HT, a micromixer with a mixing length of 12 mm containing six mixing units was obtained by sequentially applying “squeeze”, “stretch”, “twice fold”, “inverse transformation”, and “intersection” operations. Numerical simulation and Peclet Number (Pe) calculations indicated that when the squeeze amplitude 0 < α < 1/2, 0 < β < 1/2, the stretch amplitude γ > 4, and Re ≥ 1, the mass transfer in the mixer was dominated by convective diffusion induced by chaotic flow. When Re = 10, at the outlet of the mixing chamber, the simulated mixing index was 96.4%, which was far less than the value at Re = 0.1 (σ = 0.041). Microscope images of the mixing chamber and the curve trend of pH buffer solutions obtained from a mixing experiment were both consistent with the results of the simulation. When Re = 10, the average mixing index of the pH buffer solutions was 91.75%, which proved the excellent mixing efficiency of the mixer based on the 3D HT.