bluuebunny/crossref_metadata_2025 huggingface dataset:
Knowledge about E-Cigarettes and Tobacco Harm Reduction among Public Health Residents in Europe
Authors: Ferrara Pietro , Shantikumar Saran , Cabral Veríssimo Vítor , Ruiz-Montero Rafael , Masuet-Aumatell Cristina , Ramon-Torrell Josep ,   the EuroNet MRPH Working Group on Electronic Cigarettes and Tobacco Harm Reduction
Published: June 2019

Introduction: Although electronic cigarettes (e-cigarettes) and other tobacco-related products are becoming widely popular as alternatives to tobacco, little has been published on the knowledge of healthcare workers about their use. Thus, the aim of this study was to elicit the current knowledge and perceptions about e-cigarettes and tobacco harm reduction (THR) among medical residents in public health (MRPH). Material and Methods: A Europe-wide cross-sectional study was carried out amongst MRPH from the countries associated with the European Network of MRPH from April to October 2018 using an online questionnaire. Results: 256 MRPHs agreed to participate in the survey. Approximately half the participants were women (57.4%), with a median age of 30 years, and were mainly Italian (26.7%), Spanish (16.9%) and Portuguese (16.5%). Smoking prevalence was 12.9%. Overall, risk scores significantly differed for each investigated smoking product when compared with e-cigarettes; with tobacco cigarettes and snus perceived as more risky, and nicotine replacement therapy (NRT) and non-NRT oral medications seen as less risky (p < 0.01 for all). Regarding the effects of nicotine on health, the vast majority of MRPHs associated nicotine with all smoking-related diseases. Knowledge of THR was low throughout the whole sample. Conclusions: European MRPH showed a suboptimal level of knowledge about e-cigarettes and THR. Training programs for public health and preventive medicine trainees should address this gap.
Pregnancy with Heart Disease: Maternal Outcomes and Risk Factors for Fetal Growth Restriction
Authors: Nguyen Manh Thang , Bui Van Nhon , Le Thi Huyen , Vo Hoang Long , Nguyen Si Anh Hao , Trinh Thi Thu Huong , Nguyen Xuan Thuc , Vu Thi Nga , Minh Le Bui , Chu Dinh-Toi
Published: June 2019

Caring for children and mothers suffering from cardiac disease is highly challenging, with issues including late diagnosis as well as inadequate infrastructure and supply of drugs. We aimed to evaluate maternal outcomes among pregnant women suffering from heart disease with a live birth, and explored the risk factors for fetal growth restriction among these patients. A retrospective study was performed at the National Hospital of Obstetrics and Gynecology (Hanoi, Vietnam) over a 3-year period from 2014 to 2016. A total of 284 patients were enrolled in the study. Overall, most women were aged below 35 years and were diagnosed with heart disease before pregnancy. Of the women experiencing rheumatic heart disease, the prevalence of mitral valve regurgitation was the highest (40.14%), while the figure for aortic valve regurgitation was the lowest (4.23%). Of women with congenital heart defects, the most common defects were ventricular septal defect (VSD) and atrial septal defect (ASD) (19.37% and 16.55%, respectively), while 5.28% of mothers were diagnosed with tetralogy of Fallot and 1.76% with patent ductus arteriosus. Noted clinical presentations of the patients included palpitation (63.38%), breathlessness (23.59%), leg edema (8.45%), and chest pain (8.1%). The common complications in the study population included 16.90% of women having heart failure and 19.37% having arrhythmias. The incidence of fetal growth restriction was 9.15%. Hypertension (odds ratio (OR): 59.75, 95% confidence interval (CI): 9.1–392.17), the heart disease types (ASD (OR: 4.27, 95% CI: 1.19–15.29) and tetralogy of Fallot (OR: 6.82, 95% CI: 1.21–38.55)), and the complications (heart failure (OR: 10.34, 95% CI: 2.75–38.87) and pulmonary edema (OR: 107.16, 95% CI: 4.96–2313.93)) were observed as risk factors for intrauterine growth restriction. This study provides a cornerstone to promote further studies and to motivate people to apply evidence-based medical care for mothers with diagnosed cardiac disease in the antenatal and postnatal periods.
Leisure Activities of Healthy Children and Adolescents
Authors: Auhuber Lea , Vogel Mandy , Grafe Nico , Kiess Wieland , Poulain Tanja
Published: June 2019

The objective of the present study was to give a detailed overview on the leisure behavior of adolescents (frequency, differences between gender, age groups and social class, time trends, and inter-relations). In total, 1449 10- to 18-year-old German adolescents were included in the study. Participants answered questionnaires about their media use, physical activity, outdoor time, engagement in choir/orchestra and theater/dancing, social life and socio-economic status (SES). The results revealed that girls, children with lower SES as well as older children reported to use screen-based media more often and that girls, older children and children with lower SES were less physically active. In addition, boys and children with lower SES engaged less frequently in choir/orchestra and theater/dancing, while children with higher SES met their friends more often. The time trend analysis showed that mobile phone use increased drastically from 2011 to 2017, while engagement in choir/orchestra and theater/dancing decreased. Regarding the inter-relation between leisure activities, high screen times were significantly associated with less physical activity and less outdoor time. Physical activity, in contrast, was significantly related to better social life and more outdoor time. These findings highlight the growing importance of electronic media in adolescents’ lives and their tendency to displace other leisure activities.
Agglomerative Clustering of Enteric Infections and Weather Parameters to Identify Seasonal Outbreaks in Cold Climates
Authors: Stashevsky Pavel S. , Yakovina Irina N. , Alarcon Falconi Tania M. , Naumova Elena N.
Published: June 2019

The utility of agglomerative clustering methods for understanding dynamic systems that do not have a well-defined periodic structure has not yet been explored. We propose using this approach to examine the association between disease and weather parameters, to compliment the traditional harmonic regression models, and to determine specific meteorological conditions favoring high disease incidence. We utilized daily records on reported salmonellosis and non-specific enteritis, and four meteorological parameters (ambient temperature, dew point, humidity, and barometric pressure) in Barnaul, Russia in 2004–2011, maintained by the CliWaDIn database. The data structure was examined using the t-distributed stochastic neighbor embedding (t-SNE) method. The optimal number of clusters was selected based on Ward distance using the silhouette metric. The selected clusters were assessed with respect to their density and homogeneity. We detected that a well-defined cluster with high counts of salmonellosis occurred during warm summer days and unseasonably warm days in spring. We also detected a cluster with high counts of non-specific enteritis that occurred during unusually “very warm” winter days. The main advantage offered by the proposed technique is its ability to create a composite of meteorological conditions—a rule of thumb—to detect days favoring infectious outbreaks for a given location. These findings have major implications for understanding potential health impacts of climate change.
Effectiveness and Estimation of Cost-Effectiveness of a Group-Based Multicomponent Physical Exercise Programme on Risk of Falling and Frailty in Community-Dwelling Older Adults
Authors: Alhambra-Borrás Tamara , Durá-Ferrandis Estrella , Ferrando-García Maite
Published: June 2019

This study analyses the effectiveness and cost-effectiveness of a group-based multicomponent physical exercise programme aimed at reducing the risk of falling and frailty in community-dwelling older adults. This is a pretest–posttest non-equivalent control group design, with an intervention group and a comparison group. Participants were evaluated at baseline and after 9 months. The effectiveness analyses showed significant reduction in the risk of falling (−45.5%; p = 0.000) and frailty (−31%; p = 0.000) after the intervention for the participants in the physical exercise programme. Moreover, these participants showed an improvement in limitations in activities of daily living, self-care ability and the use of health resources, physical performance, balance and body mass index. The cost-effectiveness analyses showed that the intervention was cost-saving and more effective than usual care scenario. A novel group-based multicomponent physical exercise programme showed to be more effective and cost-effective than usual care for older adults suffering from risk of falling and frailty.
Heavy Metals in Agricultural Soils of the Lihe River Watershed, East China: Spatial Distribution, Ecological Risk, and Pollution Source
Authors: Chen Lian , Wang Genmei , Wu Shaohua , Xia Zhen , Cui Zhenang , Wang Chunhui , Zhou Shenglu
Published: June 2019

Concentrations of cadmium, chromium, copper, nickel, lead, and zinc in agricultural soils at 32 sites in the Lihe River Watershed of the Taihu region, East China, and their potential ecological risks and possible sources were investigated. Enrichment factor analysis demonstrated enrichment in the order Cd > Pb > Zn > Cu > Ni > Cr. The potential ecological risk index and risk assessment code analyses indicated that, of the metals studied, Cd posed the most significant ecological risk in the study area. Statistical analyses, GIS mapping, and enrichment factor analysis suggested that Cd, Pb, Cu, and Zn were derived mainly from anthropogenic sources, including agricultural, industrial, and vehicular emissions, while Cr and Ni were mainly from natural sources. Positive matrix factorization revealed that Cd, Cr, Cu, Ni, Pb, and Zn were sourced from industrial and vehicular emissions (73.7%, 21.3%, 71.4%, 20.3%, 75.0%, and 62.2%, respectively), the agricultural sector (26.3%, 36.3%, 6.8%, 38.9%, 15.7%, and 6.9%, respectively), and parent materials (0%, 42.4%, 21.8%, 40.8%, 9.2%, and 30.9%, respectively). It was recommended that strategies be implemented to reduce industrial point-source pollution.
Changes of Atmospheric and Blood Concentrations of Lead and Cadmium in the General Population of South Korea from 2008 to 2017
Authors: Ahn Jaeouk , Kim Nam-Soo , Lee Byung-Kook , Oh Inbo , Kim Yangho
Published: June 2019

We measured changes in atmospheric and blood levels of lead and cadmium in the South Korean general population during the past decade. Blood data of 16,873 adults were taken from the Korean National Health and Nutrition Examination Survey (KNHANES, 2008–2017). Atmospheric data were taken from 66 air quality monitoring sites in 16 different regions in South Korea. From 2008 to 2017, the geometric mean (GM) blood lead level decreased from 2.37 to 1.46 μg/dL (38.4% decrease), and the atmospheric lead concentration decreased by 61.0% in the overall population. During this time, the GM blood cadmium level decreased from 0.88 to 0.72 μg/L (18.2% decrease), and the atmospheric cadmium concentration decreased by 63.6%. Multiple linear regression analysis indicated that a half reduction in air lead was associated with a 0.09 μg/dL decrease in blood lead (95% CI: 0.03 to 0.15) in a subgroup of the metropolitan city population. However, a half reduction in air cadmium had no significant effect on blood cadmium. Multiple linear regression analyses indicated that the decrease in blood lead level over 10 years in Korea was related to the decrease in atmospheric lead concentration. However, the decrease in blood cadmium level during this time was not significantly associated with the decrease in atmospheric cadmium concentration. Our findings suggest that inhalation is a major source of lead exposure, but not of cadmium exposure. Ingestion of dietary cadmium presumably has a stronger impact on blood cadmium levels.
A Data Augmentation Strategy Based on Simulated Samples for Ship Detection in RGB Remote Sensing Images
Authors: Yan Yiming , Tan Zhichao , Su Nan
Published: June 2019

In this paper, we propose a data augmentation method for ship detection. Inshore ship detection using optical remote sensing imaging is a challenging task owing to an insufficient number of training samples. Although the multilayered neural network method has achieved excellent results in recent research, a large number of training samples is indispensable to guarantee the accuracy and robustness of ship detection. The majority of researchers adopt such strategies as clipping, scaling, color transformation, and flipping to enhance the samples. Nevertheless, these methods do not essentially increase the quality of the dataset. A novel data augmentation strategy was thus proposed in this study by using simulated remote sensing ship images to augment the positive training samples. The simulated images are generated by true background images and three-dimensional models on the same scale as real ships. A faster region-based convolutional neural network (Faster R-CNN) based on Res101netwok was trained by the dataset, which is composed of both simulated and true images. A series of experiments is designed under small sample conditions; the experimental results show that better detection is obtained with our data augmentation strategy.
The Effects of Poncirus fructus on Insulin Resistance and the Macrophage-Mediated Inflammatory Response in High Fat Diet-Induced Obese Mice
Authors: Kim Mia , Seol Mi Hyeon , Lee Byung-Cheol
Published: June 2019

Obesity is a chronic low-grade inflammatory condition in which hypertrophied adipocytes and adipose tissue immune cells, mainly macrophages, contribute to increased circulating levels of proinflammatory cytokines. Obesity-associated chronic low-grade systemic inflammation is considered a focal point and a therapeutic target in insulin resistance and metabolic diseases. We evaluate the effect of Poncirus fructus (PF) on insulin resistance and its mechanism based on inflammatory responses in high-fat diet (HFD)-induced obese mice. Mice were fed an HFD to induce obesity and then administered PF. Body weight, epididymal fat and liver weight, glucose, lipid, insulin, and histologic characteristics were evaluated to determine the effect of PF on insulin resistance by analyzing the proportion of macrophages in epididymal fat and liver and measured inflammatory gene expression. PF administration significantly decreased the fasting and postprandial glucose, fasting insulin, HOMA-IR, total-cholesterol, triglycerides, and low-density lipoprotein cholesterol levels. The epididymal fat tissue and liver showed a significant decrease of fat accumulation in histological analysis. PF significantly reduced the number of adipose tissue macrophages (ATMs), F4/80+ Kupffer cells, and CD68+ Kupffer cells, increased the proportion of M2 phenotype macrophages, and decreased the gene expression of inflammatory cytokines. These results suggest that PF could be used to improve insulin resistance through modulation of macrophage-mediated inflammation and enhance glucose and lipid metabolism.
Single Crystal FLIM Characterization of Clofazimine Loaded in Silica-Based Mesoporous Materials and Zeolites
Authors: Angiolini Lorenzo , Cohen Boiko , Douhal Abderrazzak
Published: June 2019

Clofazimine (CLZ) is an effective antibiotic used against a wide spectrum of Gram-positive bacteria and leprosy. One of its main drawbacks is its poor solubility in water. Silica based materials are used as drug delivery carriers that can increase the solubility of different hydrophobic drugs. Here, we studied how the properties of the silica framework of the mesoporous materials SBA-15, MCM-41, Al-MCM-41, and zeolites NaX, NaY, and HY affect the loading, stability, and distribution of encapsulated CLZ. Time-correlated single-photon counting (TCSPC) and fluorescence lifetime imaging microscopy (FLIM) experiments show the presence of neutral and protonated CLZ (1.3–3.8 ns) and weakly interacting aggregates (0.4–0.9 ns), along with H- and J-type aggregates (<0.1 ns). For the mesoporous and HY zeolite composites, the relative contribution to the overall emission spectra from H-type aggregates is low (<10%), while for the J-type aggregates it becomes higher (~30%). For NaX and NaY the former increased whereas the latter decreased. Although the CLZ@mesoporous composites show higher loading compared to the CLZ@zeolites ones, the behavior of CLZ is not uniform and its dynamics are more heterogeneous across different single mesoporous particles. These results may have implication in the design of silica-based drug carriers for better loading and release mechanisms of hydrophobic drugs.
Roles of E-cadherin and Noncoding RNAs in the Epithelial–mesenchymal Transition and Progression in Gastric Cancer
Authors: Bure Irina V. , Nemtsova Marina V. , Zaletaev Dmitry V.
Published: June 2019

The epithelial–mesenchymal transition (EMT) is thought to be at the root of invasive and metastatic cancer cell spreading. E-cadherin is an important player in this process, which forms the structures that establish and maintain cell–cell interactions. A partial or complete loss of E-cadherin expression in the EMT is presumably mediated by mechanisms that block the expression of E-cadherin regulators and involve the E-cadherin-associated transcription factors. The protein is involved in several oncogenic signaling pathways, such as the Wnt/β-catenin, Rho GTPase, and EGF/EGFR, whereby it plays a role in many tumors, including gastric cancer. Such noncoding transcripts as microRNAs and long noncoding RNAs—critical components of epigenetic control of gene expression in carcinogenesis—contribute to regulation of the E-cadherin function by acting directly or through numerous factors controlling transcription of its gene, and thus affecting not only cancer cell proliferation and metastasis, but also the EMT. This review focuses on the role of E-cadherin and the non-coding RNAs-mediated mechanisms of its expressional control in the EMT during stomach carcinogenesis.
Early Immunological Effects of Ischemia-Reperfusion Injury: No Modulation by Ischemic Preconditioning in a Randomised Crossover Trial in Healthy Humans
Authors: Lange Thomas H. , Eijken Marco , Baan Carla , Petersen Mikkel Steen , Bibby Bo Martin , Jespersen Bente , Møller Bjarne K.
Published: June 2019

Ischemic preconditioning (IPC) has been protective against ischemia-reperfusion injury (IRI), but the underlying mechanism is poorly understood. We examined whether IPC modulates the early inflammatory response after IRI. Nineteen healthy males participated in a randomised crossover trial with and without IPC before IRI. IPC and IRI were performed by cuff inflation on the forearm. IPC consisted of four cycles of five minutes followed by five minutes of reperfusion. IRI consisted of twenty minutes followed by 15 min of reperfusion. Blood was collected at baseline, 0 min, 85 min and 24 h after IRI. Circulating monocytes, T-cells subsets and dendritic cells together with intracellular activation markers were quantified by flow cytometry. Luminex measured a panel of inflammation-related cytokines in plasma. IRI resulted in dynamic regulations of the measured immune cells and their intracellular activation markers, however IPC did not significantly alter these patterns. Neither IRI nor the IPC protocol significantly affected the levels of inflammatory-related cytokines. In healthy volunteers, it was not possible to detect an effect of the investigated IPC-protocol on early IRI-induced inflammatory responses. This study indicates that protective effects of IPC on IRI is not explained by direct modulation of early inflammatory events.
Chain Structure in a Cross-Linked Polyurethane Magnetic Elastomer Under a Magnetic Field
Authors: Watanabe Mayuko , Takeda Yoshihiro , Maruyama Takayuki , Ikeda Junko , Kawai Mika , Mitsumata Tetsu
Published: June 2019

The morphology of magnetic particles with a size of 7.0 μm was observed for magnetic elastomers with a concentration of magnetic particles of 70 wt% using an X-ray microscope remolded into high resolution. Computed tomography images revealed that magnetic particles were distributed isotopically in the absence of a magnetic field, but they formed a chain structure in the polyurethane network under a magnetic field of 270 mT. It was also established, by image analysis, that magnetic elastomers had an anisotropic structure under the magnetic field.
Activation of TGF-β Canonical and Noncanonical Signaling in Bovine Lactoferrin-Induced Osteogenic Activity of C3H10T1/2 Mesenchymal Stem Cells
Authors: Li Yixuan , Zhang Wei , Ren Fazheng , Guo Huiyuan
Published: June 2019

Lactoferrin (LF) is known to modulate the bone anabolic effect. Previously, we and others reported that the effects of LF on the bone may be conferred by the stimulation of transforming growth factor β (TGF-β) signaling in the preosteoblast. However, the underlying molecular mechanisms of LF-induced osteogenic differentiation of mesenchymal stem cells (MSCs) has not been identified. In this study, we tested the hypothesis that the effects of LF on osteogenesis of MSCs required mediation by TGF-β Receptors and activating TGF-β signaling pathway. Using siRNA silencing technology, the knockdown of TGF-β Receptor II (TβRII) could significantly attenuate LF’s effect on the proliferation rate and alkaline phosphatase (ALP) activity of MSCs. It indicated that LF induced osteogenic activity that is dependent on TβRII in C3H10T1/2. Subsequently, it was shown that LF activated Smad2. Downregulating TGF-β Receptor I (TβRI) with SB431542 attenuated the expression of p-Smad2 and p-P38, also the LF-induced the osteogenic activity. Besides, the stimulation by LF on the expression of Osteocalcin (OCN), Osteopontin (OPN), Collagen-2a1 (Col2a1), and Fibroblast Growth Factor 2 (FGF2) were abolished by SB431542. These results confirmed that LF induced osteogenic activity though the TGF-β canonical and noncanonical signaling pathway. This study provided the first evidence of the signaling mechanisms of LF’s effect on osteogenesis in MSCs.
Extracellular-Signal Regulated Kinase: A Central Molecule Driving Epithelial–Mesenchymal Transition in Cancer
Authors: Olea-Flores Monserrat , Zuñiga-Eulogio Miriam Daniela , Mendoza-Catalán Miguel Angel , Rodríguez-Ruiz Hugo Alberto , Castañeda-Saucedo Eduardo , Ortuño-Pineda Carlos , Padilla-Benavides Teresita , Navarro-Tito Napoleón
Published: June 2019

Epithelial–mesenchymal transition (EMT) is a reversible cellular process, characterized by changes in gene expression and activation of proteins, favoring the trans-differentiation of the epithelial phenotype to a mesenchymal phenotype. This process increases cell migration and invasion of tumor cells, progression of the cell cycle, and resistance to apoptosis and chemotherapy, all of which support tumor progression. One of the signaling pathways involved in tumor progression is the MAPK pathway. Within this family, the ERK subfamily of proteins is known for its contributions to EMT. The ERK subfamily is divided into typical (ERK 1/2/5), and atypical (ERK 3/4/7/8) members. These kinases are overexpressed and hyperactive in various types of cancer. They regulate diverse cellular processes such as proliferation, migration, metastasis, resistance to chemotherapy, and EMT. In this context, in vitro and in vivo assays, as well as studies in human patients, have shown that ERK favors the expression, function, and subcellular relocalization of various proteins that regulate EMT, thus promoting tumor progression. In this review, we discuss the mechanistic roles of the ERK subfamily members in EMT and tumor progression in diverse biological systems.
Large Scale Linguistic Processing of Tweets to Understand Social Interactions among Speakers of Less Resourced Languages: The Basque Case
Authors: Fernandez de Landa Joseba , Agerri Rodrigo , Alegria Iñaki
Published: June 2019

Social networks like Twitter are increasingly important in the creation of new ways of communication. They have also become useful tools for social and linguistic research due to the massive amounts of public textual data available. This is particularly important for less resourced languages, as it allows to apply current natural language processing techniques to large amounts of unstructured data. In this work, we study the linguistic and social aspects of young and adult people’s behaviour based on their tweets’ contents and the social relations that arise from them. With this objective in mind, we have gathered over 10 million tweets from more than 8000 users. First, we classified each user in terms of its life stage (young/adult) according to the writing style of their tweets. Second, we applied topic modelling techniques to the personal tweets to find the most popular topics according to life stages. Third, we established the relations and communities that emerge based on the retweets. We conclude that using large amounts of unstructured data provided by Twitter facilitates social research using computational techniques such as natural language processing, giving the opportunity both to segment communities based on demographic characteristics and to discover how they interact or relate to them.
Identification and Virulence Characterization of Two Akanthomyces attenuatus Isolates Against Megalurothrips usitatus (Thysanoptera: Thripidae)
Authors: Du Cailian , Yang Bo , Wu Jianhui , Ali Shaukat
Published: June 2019

Megalurothrips usitatus (Bagnall) is one of the most harmful pests of leguminous plants. In order to expand our knowledge on the infection of M. usitatus by entomopathogenic fungi, two newly identified isolates of Akanthomyces attenuatus (Zare & Gams) were tested for their pathogenicity against M. usitatus. Both isolates of A. attenuatus (SCAUDCL-38 and SCAUDCL-56) were isolated from soil and were identified by morphological and molecular analyses. The adult females of M. usitatus were treated with five different concentrations (1 × 104, 1 × 105, 1 × 106, 1 × 107, and 1 × 108 conidia/mL) of the isolates. Our results revealed 76.25% and 57.5% mortality of M. usitatus after five days of treatment with 1 × 108 conidia/mL of SCAUDCL-38 and SCAUDCL-56, respectively. The median lethal concentrations (LC50) of SCAUDCL-38 and SCAUDCL-56 calculated through linear regression analysis after five days of fungal treatment of M. usitatus were 1.9 × 106 and 1.5 × 107 conidia/mL, respectively, whereas the median lethal time (LT50) observed for 1 × 108 conidia/mL of SCAUDCL-38 and SCAUDCL-56 were 3.52 days and 4.9 days, respectively. A. attenuatus isolates SCAUDCL-38 and SCAUDCL-56 are highly pathogenic strains of M. usitatus. These findings offer valuable information on the development and commercialization of alternative control measures against M. usitatus.
Three-Dimensional Characterization of Hardened Paste of Hydrated Tricalcium Silicate by Serial Block-Face Scanning Electron Microscopy
Authors: Zhao Yongjuan , Liu Xianping , Chen Bo , Yang Fei , Zhang Yongming , Wang Peiming , Robinson Ian
Published: June 2019

With the application of a three-dimensional (3D) characterization technique, serial block-face scanning electron microscopy (SBFSEM), the 3D microstructure of a hydrated cement monomineral, tricalcium silicate (C3S), was measured with nanoscale resolution. The 3D morphologies of anhydrous particles, hydrated products, and capillary pores were visualized. Closed and open pores were discovered inside an anhydrous particle. The size and distribution of both the anhydrous C3S particles and their capillary pores were analyzed quantitatively and the porosity was determined to be 9%. The distribution of pores was found to be in a good agreement with the inner and outer product model of Hu et. al., with an inner shell distance of 860 nm. Considering the spatial resolution of the instrument and the volume of sample measured, most pores in this experiment could be characterized as capillary pores.
Testing and Prediction of the Strength Development of Recycled-Aggregate Concrete with Large Particle Natural Aggregate
Authors: Li Changyong , Wang Fei , Deng Xiangsheng , Li Yizhuo , Zhao Shunbo
Published: June 2019

In this paper, a new recycled aggregate concrete (RAC) was produced with composite coarse aggregate and fine recycled aggregate. The composite coarse aggregate was mixed into continuous gradation by large particle natural aggregate with small particle recycled aggregate. To explore the time-dependent developments of the compressive strength and splitting tensile strength of this new RAC, 320 groups of cubic specimens were tested at different curing ages from 3 days to 360 days to measure the compressive and splitting tensile strengths. The amount of large particle natural aggregate varied from zero to 70% in mass of the total coarse aggregate. The water/cement ratio was taken as 0.60, 0.49, 0.41 and 0.36 to represent four strength grades of the RAC at about C20, C30, C40 and C50. Based on the tested results, the curves of the compressive and tensile strengths of the RAC that changed with curing age are plotted, which clearly exhibit that the amount of large particle natural aggregate had a rational range in different strength grades of the RAC which had better aging strength. When the RAC was no larger than C30 with a water/cement ratio of 0.60 and 0.49, the amount of large particle natural aggregate should be no more than 30%; when the RAC was no less than C40 with a water/cement ratio of 0.41 and 0.36, the amount of large particle natural aggregate should be no less than 50%. Along with the general prediction of the strength development of all the tested RAC, the optimal predictive formulas are proposed for the strength development of RAC with a rational amount of natural aggregate. Meanwhile, the strength developments of RAC with a rational amount of natural aggregate are assessed by the time-dependent models proposed by the ACI Committee 209 and CEB-FIP MC 2010.
Ultra-Broadband Absorption from 750.0 nm to 5351.6 nm in a Novel Grating Based on SiO2-Fe-Sandwich Substrate
Authors: Wu Zhaofeng , Liu Hanqing , Yang Hui , Liu Jibin , Liu Peiguo
Published: June 2019

In this paper, we design a three-part-period grating based on alternating Fe/SiO 2 sandwich structure, which can achieve an ultra-broadband absorption from 750.0 nm to 5351.6 nm. In particular, the absorbing efficiency can reach to more than 95% within 2158.8 nm, which is due to the well impedance matching of Fe with the free space, as well as due to the excitation of localized surface plasmon resonance and surface propagation plasmon resonance in the proposed structure. Furthermore, multiple period gratings are also discussed to broaden the absorption band. These results are very promising for applications in high-performance photovoltaics, nonlinear optics devices and protective equipment for laser weapons.
Comparative Study on Constitutive Models for 21-4N Heat Resistant Steel during High Temperature Deformation
Authors: Li Yiming , Ji Hongchao , Cai Zhongman , Tang Xuefeng , Li Yaogang , Liu Jinping
Published: June 2019

The Gleeble-1500D thermal simulation test machine was used to conduct the isothermal compression test on 21-4N at the strain rate ( ε ˙ ) of 0.01–10 s−1, the deformation temperature (T) of 1273–1453 K and the maximum deformation is 0.916. The data of the stress-strain (σ-ε) were obtained. Based on the σ-ε data, the Johnson-Cook (J-C), modified J-C, Arrhenius and Back-Propagation Artificial Neural Network (BP-ANN) models were established. The accuracy of four models were verified, analyzed and compared. The results show that J-C model has a higher accuracy only under reference deformation conditions. When the deformation condition changes greatly, the accuracy of J-C model is significantly reduced. The coupling effect of T and ε ˙ of modified J-C model is considered, and the prediction accuracy is greatly improved The Arrhenius model introduces Zener-Hollomon (Z) to represent the coupling effect of T and ε ˙ , it has a fairly high prediction accuracy. And it can predict flow stress (σ) accurately at different conditions. The accuracy of BP-ANN model is the highest, but its learning rate is low, the learning and memory are unstable. It has no memory for the weights and thresholds of the completed training. So, there are certain limitations of it in use. Finally, a Finite Element Method (FEM) of the isothermal compression experiment for four models were established, and the distribution of the equivalent stress field, equivalent strain field and temperature field with the deformation degree of 60% were obtained.
Design of Low RCS Circularly Polarized Patch Antenna Array Using Metasurface for CNSS Adaptive Antenna Applications
Authors: Li Jianxing , Khan Tayyab A. , Chen Juan , Raza Muhammad U. , Zhang Anxue
Published: June 2019

A low radar cross section (RCS) circularly polarized patch antenna array operating at the downlink S-band (2492 ± 5 MHz) of the Chinese Compass Navigation Satellite System (CNSS) is proposed. The low RCS is achieved by replacing the conventional metallic ground with an artificial magnetic conductor (AMC)-based metasurface. Two different AMC unit cells are designed having a phase difference within 180 ± 37° and combined in a chessboard-like configuration to realize the AMC-based metasurface. Furthermore, the AMC-based metasurface is utilized as the ground of the CNSS array for wideband RCS reduction. A wideband RCS reduction from 6 GHz to 17 GHz is achieved due to the wideband diffusion property of the AMC unit cells. The maximum RCS reduction is more than 14 dB at 13.3 GHz irrespective of the polarization direction of the incident waves. Moreover, the circular polarization (CP) performance is realized by embedding a circular slot on the patch radiator of the antenna element. The radiation characteristics of the CNSS array are hardly impacted by the inclusion of the metasurface-based ground. The proposed CNSS array has been fabricated and measured. The measurement results are in reasonable agreement with the simulations. The proposed CNSS array can be a good candidate for CNSS adaptive antenna applications where low RCS is simultaneously demanded.
Effects of Expansive Agents on the Early Hydration Kinetics of Cementitious Binders
Authors: Miao Miao , Liu Qingyang , Zhou Jian , Feng Jingjing
Published: June 2019

The addition of expansive agents could overcome the main disadvantages of raw concrete including high brittleness and low tensile strength. Few studies have investigated the early hydration kinetics of expansive cementitious binders, though the findings from the early hydration kinetics are helpful for understanding their technical performances. In this study, mixtures of 3CaO•3Al2O3•CaSO4 and CaSO4 (i.e., ZY-type™ expansive agent) with different proportions of mineral admixtures (e.g., fly ash and slag) were added into cement pastes to investigate the early hydration kinetics mechanism of expansive cementitious binders. Early hydration heat evolution rate and cumulative hydration heat were measured by isothermal calorimeter. Kinetic parameters were estimated based on the Krstulovic–Dabic model and Knudsen equations. Mechanical performances of expansive cementitious binders were tested in order to evaluate if they met the basic requirements of shrinkage-compensating materials in technical use. The early hydration heat released from cementitious binders containing ZY-type™ expansive agent was much greater than that released by pure cement, supporting the idea that addition of the expansive agent would improve the reaction of cement. The early hydration kinetic rates were decreased due to the reactions of the mineral admixture (e.g., fly ash or slag) and the ZY-type™ expansive agent in the cement system. The hydration reaction of cementitious binders containing ZY-type™ expansive agent obeyed the Krstulovic–Dabic model well. Three processes are involved in the hydration reaction of cementitious binders containing ZY-type™ expansive agent. These are nucleation and crystal growth (NG), interactions at phase boundaries (I), and diffusion (D). The 14-day expansion rates of cementitious binders containing ZY-type™ expansive agent are in the range of 2.0 × 10−4 to 3.5 × 10−4, which could meet the basic requirements of anti-cracking performances in technical use according to Chinese industry standard JGJ/T 178-2009. This study could provide an insight into understanding the effects of expansive agents on the hydration and mechanical performances of cementitious binders.
Study on ASJ Cutting of TC18, Based upon Multivariate Nonlinear Regression and SA-BP-AGA
Authors: Lin Jie , Zhou Xin , Zhang Hui , Wang Fengchao , Xu Qiwen , Guo Chuwen
Published: June 2019

TC18 titanium alloy has been widely applied, but is considered as a difficult machining material. Taking the kerf angle as the quality criterion, this paper studied the cutting performance of TC18 by the use of an abrasive slurry jet (ASJ), based upon multivariate nonlinear regression and SA-BP-AGA. Cutting experiments were carried out according to the Taguchi orthogonal method. The experimental factors included traverse speed, standoff distance, pressure and slurry concentration, with five levels set, respectively. Meanwhile, a characterization method of the major influencing factors was proposed. A multiple nonlinear regression model and a back propagation artificial neural network (BP) prediction model, based on adaptive genetic algorithm (AGA), were established. The reliability was verified by statistics equations for the 22 groups of the fitting or training model and the three groups of experimental results. The BP-AGA and Simulated annealing algorithm (SA) were used to form a set of prediction optimization systems, called integrated SA-BP-AGA. Finally, the results showed that the main factor influencing the kerf angle is the slurry concentration. BP-AGA is easier to model, offers better robustness and is more accurate than a multivariate nonlinear regression model. The best kerf angle can be predicted by the integration system. The study results can improve the performance for the machining of TC18 by ASJ.
Dimensionless Analysis for Investigating the Quality Characteristics of Aluminium Matrix Composites Prepared through Fused Deposition Modelling Assisted Investment Casting
Authors: Singh Sunpreet , Prakash Chander , Antil Parvesh , Singh Rupinder , Królczyk Grzegorz , Pruncu Catalin I.
Published: June 2019

The aluminium matrix composites (AMCs) have become a tough competitor for various categories of metallic alloys, especially ferrous materials, owing to their tremendous servicing in the diversified application. In this work, additional efforts have been made to formulate a mathematical model, by using dimensionless analysis, able to predict the mechanical characteristics of the AMCs that have already been optimized and characterized by the authors. Here, the experimental and statistical data obtained from the Taguchi L18 orthogonal array and analysis of variance (ANOVA) have been used. They permit collection of the output responses and allow the identification of significant process parameters, respectively, which thereafter were used to design the mathematical model. Second order polynomial equations have been obtained from the specific output response and the relevant input parameter were incorporated with the highest level of contribution. The obtained quadratic equations indicate the regression values (R2) equal to unity, hence, proving the performances of the fit. The results demonstrate that the developed mathematical models present very high accuracy for predicting the output responses.
The Effect of SiC Content on Microstructure and Microwave Heating Rate of h-BN/SiC Ceramics Fabricated by Spark Plasma Sintering
Authors: Lun Huilin , Zeng Yi , Xiong Xiang , Zhao Lei , Li Dongling , Ye Ziming , Qian Tianxiao
Published: June 2019

Hexagonal boron nitride/silicon carbide (h-BN/SiC) ceramics were fabricated by a spark plasma sintering (SPS) method. Phase and microstructure of ceramics were characterized and observed, respectively, using the X-ray diffraction, scanning electron microscope and electron probe microanalysis. The effect of molar ratios of SiC to h-BN on the microstructure, relative density, hardness, thermal conductivity, and the heating rate by microwaves on the ceramics were investigated. The results showed that the orientation of flake-like h-BN was significantly influenced by SiC content in h-BN/SiC ceramics. With the increasing of SiC content, the h-BN flakes gradually became an isotropic distribution from the preferred orientation aligning in a SPS pressure direction. The relative density of h-BN/SiC ceramics was 97.6 ± 0.9% at a molar ratio of SiC to h-BN of 40/60 mol%. The preferential orientation of h-BN flakes contributed to a relatively high thermal conductivity along the SPS pressure direction, which was beneficial to increasing the heating rate of h-BN/SiC ceramics in microwave fields.
A Study on Modified Bitumen with Metal Doped Nano-TiO2 Pillared Montmorillonite
Authors: Jin Jiao , Chen Bozhen , Liu Lang , Liu Ruohua , Qian Guoping , Wei Hui , Zheng Jianlong
Published: June 2019

TiO2 pillared montmorillonite (T/M) modifiers have been studied to alleviate the aging of asphalt pavement and degrade automobile exhaust, but the photocatalytic activity of ordinary TiO2 is not good enough. In this study, in order to improve the photocatalytic performance of T/M, different metal (Ce, Cu, Fe) doped modifiers were prepared based on T/M. Metal doped TiO2 pillared montmorillonite was prepared by the sol-gel method. The modifier was characterized by X-ray diffraction (XRD) and an Ultraviolet visible (UV-Vis) spectrophotometer. The results show that TiO2 with different metal ions successfully entered into the layer of organic montmorillonite (OMMT) to form a pillared structure. Compared with the undoped TiO2 pillared montmorillonite (T/M), the optical absorption edge of the metal doped TiO2 pillared montmorillonite has an obvious red shift. In addition, the influences of the different content of modifiers on the properties of the original bitumen and catalytic capacities for automobile exhaust were also investigated. The results show that Ce doped TiO2 (Ce-T/M) pillared montmorillonite has the best improvement in high temperature performance and ultraviolet (UV) resistance of bitumen. In the experiment of automobile exhaust degradation, the degradation law of NO and HC showed Cu-T/M > Ce-T/M > Fe-T/M > T/M. These three kinds of metal ions can effectively improve the photocatalytic degradation efficiency of T/M.
Antimicrobial and Immunomodulatory Properties and Applications of Marine-Derived Proteins and Peptides
Authors: Kang Hee Kyoung , Lee Hyung Ho , Seo Chang Ho , Park Yoonkyung
Published: June 2019

Marine organisms provide an abundant source of potential medicines. Many of the marine-derived biomaterials have been shown to act as different mechanisms in immune responses, and in each case they can significantly control the immune system to produce effective reactions. Marine-derived proteins, peptides, and protein hydrolysates exhibit various physiologic functions, such as antimicrobial, anticancer, antioxidant, antihypertensive, and anti-inflammatory activities. Recently, the immunomodulatory properties of several antimicrobial peptides have been demonstrated. Some of these peptides directly kill bacteria and exhibit a variety of immunomodulatory activities that improve the host innate immune response and effectively eliminate infection. The properties of immunomodulatory proteins and peptides correlate with their amino acid composition, sequence, and length. Proteins and peptides with immunomodulatory properties have been tested in vitro and in vivo, and some of them have undergone different clinical and preclinical trials. This review provides a comprehensive overview of marine immunomodulatory proteins, peptides, and protein hydrolysates as well as their production, mechanisms of action, and applications in human therapy.
In Silico Transcriptomic Analysis of Wound-Healing-Associated Genes in Malignant Pleural Mesothelioma
Authors: Rouka Erasmia , Beltsios Eleftherios , Goundaroulis Dimos , Vavougios Georgios D. , Solenov Evgeniy I. , Hatzoglou Chrissi , Gourgoulianis Konstantinos I. , Zarogiannis Sotirios G.
Published: June 2019

Background and objectives: Malignant pleural mesothelioma (MPM) is a devastating malignancy with poor prognosis. Reliable biomarkers for MPM diagnosis, monitoring, and prognosis are needed. The aim of this study was to identify genes associated with wound healing processes whose expression could serve as a prognostic factor in MPM patients. Materials and Methods: We used data mining techniques and transcriptomic analysis so as to assess the differential transcriptional expression of wound-healing-associated genes in MPM. Moreover, we investigated the potential prognostic value as well as the functional enrichments of gene ontologies relative to microRNAs (miRNAs) of the significantly differentially expressed wound-healing-related genes in MPM. Results: Out of the 82 wound-healing-associated genes analyzed, 30 were found significantly deregulated in MPM. Kaplan–Meier analysis revealed that low ITGAV gene expression could serve as a prognostic factor favoring survival of MPM patients. Finally, gene ontology annotation enrichment analysis pointed to the members of the hsa-miR-143, hsa-miR-223, and the hsa-miR-29 miRNA family members as important regulators of the deregulated wound healing genes. Conclusions: 30 wound-healing-related genes were significantly deregulated in MPM, which are potential targets of hsa-miR-143, hsa-miR-223, and the hsa-miR-29 miRNA family members. Out of those genes, ITGAV gene expression was a prognostic factor of overall survival in MPM. Our results highlight the role of impaired tissue repair in MPM development and should be further validated experimentally.
Effect of Al2O3 on the Formation of Calcium Ferrite in the Solid State
Authors: Bai Kaikai , Shen Jiangwei , Zhu Zhenglu , Zuo Haibin , Pan Yuzhu , Wang Jingsong , Xue Qingguo
Published: June 2019

Pure chemical reagents Fe2O3, Al2O3, and Ca(OH)2 were used to investigate the formation of calcium ferrite in the solid state. The phase composition of the prepared samples was determined using X-ray powder diffraction and by SEM. The TG-DSC analysis was performed to analyze the decomposition behavior and formation of calcium ferrites. The formation rate of calcium ferrite was determined by in-situ X-ray diffraction (XRD) and by the K-value method. The X-ray diffraction analysis was performed using Pt as the internal standard for application of the K-value method. The formation of Ca2Fe2O5 (C2F) occurred much earlier than the formation of CaFeO4 (CF). C2F and CF were formed at approximately 600 °C and 700–800 °C, respectively. With an increase of Al2O3 content, there was a tendency to decrease the melting temperature. There was a heating scheme in this study (i.e., 10 °C per minute to 1250 °C under a flowing atmosphere of high-purity air). The total amount of CF increased with an increase of the Al2O3 content, and the Al2O3 content reaching the maximum value of CF was 1.4%. As the Al2O3 content increased from 1.4% to 2.8%, the total amount of CF reduced slightly. When the Al2O3 concentration was greater than 2.8%, the content of CF generated significantly decreased with the increase of Al2O3.