bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Heating Mode and Temperature on the Microstructures, Electrical and Optical Properties of Molybdenum Thin Films
Authors: Zhao Haili , Xie Jingpei , Mao Aixia , Wang Aiqin , Chen Yanfang , Liang Tingting , Ma Douqin
Published: September 2018

In this paper, molybdenum (Mo) thin films are deposited on soda-lime glass (SLG) substrates by direct current magnetron sputtering and heated in three different modes at different temperatures, including substrate heating, annealing treatment, and both substrate heating and annealing treatment. The effects of heating temperature and heating mode on the structures, morphology, optical and electrical properties of Mo thin films were systematically investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM), atomic force microscope (AFM) and UV-visible spectrophotometer (UV-vis spectra). It is shown that as the substrate and annealing temperature increase, the crystallinity of Mo thin films is improved, and the grain sizes become bigger. Especially in the mode of both substrate heating and annealing treatment at higher temperature, the obtained Mo thin films show higher crystallinity and conductivity. Moreover, with the increase of substrate and annealing temperature in different heating modes, both the surface compactness of Mo films and the optical reflectance increase correspondingly. Furthermore, the Mo film, prepared at the substrate heating temperature of 400 °C and annealed at 400 °C, showed excellent comprehensive performance, and the resistivity is as low as 1.36 × 10−5 Ω·cm. Using this optimized Mo thin film as an electrode, copper indium gallium selenium (CIGS) solar cells have a maximum photo-conversion efficiency of 12.8%.
The Coupling Effect of O2 and H2S on the Corrosion of G20 Steel in a Simulating Environment of Flue Gas Injection in the Xinjiang Oil Field
Authors: Zhong Xiankang , Wang Yanran , Liang Jianjun , Chen Long , Song Xiaoqin
Published: September 2018

Flue gas injection for heavy oil recovery has received a great deal of attention, because it is more cost effective than lots of other injection methods. However, the corrosion could occur easily, because the flue gas usually contains corrosive gases such as CO2, H2S, and O2. In this work, the corrosion behaviors of G20 steel in flue gas injection environment simulating Xinjiang oil field (China) were investigated using weight loss measurement and surface characterization techniques. The effect of environments including the O2-containing environment, the H2S-containing environment, and the O2-H2S-coexisting environment on the corrosion of G20 steel in gas phase and liquid phase was discussed. The results show that the corrosion rate of G20 steel in the O2-H2S-coexisting environment is much higher than the sum of corrosion rates of the O2-containing environment and the H2S-containing environment, regardless of the gas phase and the liquid phase. This indicates that there is a coupling effect between O2 and H2S, which can further accelerate the corrosion of steel in O2-H2S-coexisting environment. The results of surface characterization demonstrate that in a typical flue gas injection environment, the corrosion products are composed of FeCO3, FeS, FeO(OH), and elemental sulfur. Elemental sulfur could obviously accelerate the corrosion of steel. Therefore, it can be considered that the coupling effect of O2 and H2S on corrosion of G20 steel in flue gas injection environment is caused by the formation of elemental sulfur in corrosion products.
An Authentication Code over Galois Rings with Optimal Impersonation and Substitution Probabilities
Authors: Ku-Cauich Juan Carlos , Morales-Luna Guillermo , Tapia-Recillas Horacio
Published: September 2018

Two new systematic authentication codes based on the Gray map over a Galois ring are introduced. The first introduced code attains optimal impersonation and substitution probabilities. The second code improves space sizes, but it does not attain optimal probabilities. Additionally, it is conditioned to the existence of a special class of bent maps on Galois rings.
Synthesis, Characterization, and Antifungal Property of Hydroxypropyltrimethyl Ammonium Chitosan Halogenated Acetates
Authors: Mi Yingqi , Tan Wenqiang , Zhang Jingjing , Wei Lijie , Chen Yuan , Li Qing , Dong Fang , Guo Zhanyong
Published: September 2018

Hydroxypropyltrimethyl ammonium chitosan halogenated acetates were successfully synthesized from six different haloacetic acids and hydroxypropyltrimethyl ammonium chloride chitosan (HACC) with high substitution degree, which are hydroxypropyltrimethyl ammonium chitosan bromacetate (HACBA), hydroxypropyltrimethyl ammonium chitosan chloroacetate (HACCA), hydroxypropyltrimethyl ammonium chitosan dichloroacetate (HACDCA), hydroxypropyltrimethyl ammonium chitosan trichloroacetate (HACTCA), hydroxypropyltrimethyl ammonium chitosan difluoroacetate (HACDFA), and hydroxypropyltrimethyl ammonium chitosan trifluoroacetate (HACTFA). These chitosan derivatives were synthesized by two steps: first, the hydroxypropyltrimethyl ammonium chloride chitosan was synthesized by chitosan and 3-chloro-2-hydroxypropyltrimethyl ammonium chloride. Then, hydroxypropyltrimethyl ammonium chitosan halogenated acetates were synthesized via ion exchange. The structures of chitosan derivatives were characterized by Fourier transform infrared spectroscopy (FTIR), 1H Nuclear magnetic resonance spectrometer (1H NMR), 13C Nuclear magnetic resonance spectrometer (13C NMR), and elemental analysis. Their antifungal activities against Colletotrichum lagenarium, Fusarium graminearum, Botrytis cinerea, and Phomopsis asparagi were investigated by hypha measurement in vitro. The results revealed that hydroxypropyltrimethyl ammonium chitosan halogenated acetates had better antifungal activities than chitosan and HACC. In particular, the inhibitory activity decreased in the order: HACTFA > HACDFA > HACTCA > HACDCA > HACCA > HACBA > HACC > chitosan, which was consistent with the electron-withdrawing property of different halogenated acetates. This experiment provides a potential idea for the preparation of new antifungal drugs by chitosan.
Estimating the Effective Elastic Parameters of Nodular Cast Iron from Micro-Tomographic Imaging and Multiscale Finite Elements: Comparison between Numerical and Experimental Results
Authors: Pereira Andre , Costa Marcio , Anflor Carla , Pardal Juan , Leiderman Ricardo
Published: September 2018

Herein, we describe in detail a methodology to estimate the effective elastic parameters of nodular cast iron, using micro-tomography in conjunction with multiscale finite elements. We discuss the adjustment of the image acquisition parameters, address the issue of the representative-volume choice, and present a brief discussion on image segmentation. In addition, the finite-element computational implementation developed to estimate the effective elastic parameters from segmented microstructural images is described, indicating the corresponding computational costs. We applied the proposed methodology to a nodular cast iron, and estimated the graphite elastic parameters through a comparison between the numerical and experimental results.
Study on Fracture-Split Performance of 36MnVS4 and Analysis of Fracture-Split Easily-Induced Defects
Authors: Shi Zhou , Kou Shuqing
Published: September 2018

The material 36MnVS4 is the second generation of connecting rod fracture-split material. However, it generates more quality defects during the fracture-split process. To investigate the causes of defects that occurred, the material properties and fracture-split performance of the 36MnVS4 are researched and compared with C70S6. The fracture-split easily-induced defects are also analyzed. By finite element simulation and experimental analysis, the results show that the 36MnVS4 has lower carbon content and more ferrite, therefore the fracture surface of the 36MnVS4 connecting rod is more prone to tears and the plastic deformation range is greater. The fracture speed of the 36MnVS4 connecting rod is 20% lower than that of the C70S6 connecting rod. The slower fracture separation rate increases the possibility of defects generation. The crack initiation position of the 36MnVS4 connecting rod is random, scattered, and unstable, and the 36MnVS4 has higher gap sensitivity. Therefore, the 36MnVS4 connecting rod is more prone to produce quality defects in the fracture-split process. By changing the cross-section design, the outer edge of the joint surface is changed to arc-shaped, which can improve the fracture-split process of the 36MnVS4 connecting rod and reduce the processing defects.
Removal of Pb2+ in Wastewater via Adsorption onto an Activated Carbon Produced from Winemaking Waste
Authors: Alguacil Francisco José , Alcaraz Lorena , García-Díaz Irene , López Félix Antonio
Published: September 2018

This work describes the adsorption of Pb2+ in aqueous solution onto an activated carbon (AC) produced from winemaking waste (cluster stalks). After characterizing the AC using Fourier transform infrared spectroscopy (FTIR) and micro-Raman spectroscopy, the influence of different physico-chemical factors (stirring rate, temperature, pH, adsorbent concentration, etc.) on its capacity to adsorb Pb2+ was examined. Kinetic and thermodynamic studies showed that the adsorption of the Pb2+ follows a pseudo-second-order kinetic model and fits the Langmuir isotherm model, respectively. The maximum adsorption capacity of the AC was 58 mg/g at 288 K temperature and pH of 4. In conclusion, ACs made from waste cluster stalks could be successfully used to remove Pb2+ from polluted water.
Effect of CaCl2 on Microstructure of Calciothermic Reduction Products of Ti2O3 to Prepare Porous Titanium
Authors: Yang Guobo , Xu Baoqiang , Wan Heli , Wang Fengkang , Yang Bin , Wang Zhijun
Published: September 2018

The compound CaCl2 plays a significant role in the process of direct calciothermic reduction of Ti2O3 to prepare porous titanium. In this paper, the effect of CaCl2 on reduction products by calciothermic reduction of Ti2O3 was investigated. Results show that the distribution of CaCl2 in reduction preform influences particle size and morphology differences in reduction products both on the surface and the inside. The CaCl2 is transferred to the surface of the Ti2O3 preform due to its volatilization before and throughout reduction. The content of CaCl2 in the surface zone of Ti2O3 preform is significantly higher than that in the interior during the reduction process, contributing to the formation of large Ti particles with a smooth shape on the surface, and small Ti particles with inherited morphology of Ti2O3 inside. More CaCl2 causes the aggregation of Ti particles to form large Ti particles which are advantageous as they connect and form a more solid porous titanium structure. The presence of a small amount of CaCl2 in the interior also results in the coexistence of small Ti and CaO particles, forming a loose structure with uniform distribution.
Hydrogen Embrittlement Susceptibility of R4 and R5 High-Strength Mooring Steels in Cold and Warm Seawater
Authors: Artola Garikoitz , Arredondo Alberto , Fernández-Calvo Ana Isabel , Aldazabal Javier
Published: September 2018

Hydrogen embrittlement susceptibility ratios calculated from slow strain rate tensile tests have been employed to study the response of three high-strength mooring steels in cold and warm synthetic seawater. The selected nominal testing temperatures have been 3 °C and 23 °C in order to resemble sea sites of offshore platform installation interest, such as the North Sea and the Gulf of Mexico, respectively. Three scenarios have been studied for each temperature: free corrosion, cathodic protection and overprotection. An improvement on the hydrogen embrittlement tendency of the steels has been observed when working in cold conditions. This provides a new insight on the relevance of the seawater temperature as a characteristic to be taken into account for mooring line design in terms of hydrogen embrittlement assessment.
Interpretation of Hydrophobization Behavior of Dodecylamine on Muscovite and Talc Surface through Dynamic Wettability and AFM Analysis
Authors: Jiang Hao , Gao Ya , Khoso Sultan Ahmed , Ji Wanying , Hu Yuehua
Published: September 2018

In this study, a new approach, “dynamic wettability”, and atomic force microscopy (AFM) imaging analysis techniques were successfully used to characterize the hydrophobization mechanism of the collector dodecylamine (DDA) on muscovite and talc surfaces. The attachment of bubbles to the minerals was studied through the dynamic contact angle to gain a detailed understanding of the hydrophobization mechanism of DDA on a muscovite and talc surface. AFM imaging and interaction forces were performed to explain the DDA adsorption mechanism on both minerals. Finally, flotation tests were performed to verify the effectiveness of these techniques. After treatments with DDA, the contact angles became much larger compared to initial angles, particularly for muscovite, and the attachment of bubbles on the talc surface was much easier than muscovite due to its natural hydrophobicity. From AFM imaging, both the muscovite and talc showed a similar tendency; the higher the DDA concentration, the more the adsorbed amount. However, the adsorbed amount of DDA on talc surface was obviously more than that on muscovite. As far as interaction forces are concerned, the maximum attractions occurred at certain different concentrations respectively for muscovite and talc and agreed well with the AFM-imaging results. Moreover, results obtained from flotation tests were promising and quite in agreement with the phenomenon of these techniques.
Effect of Storage Conditions on Phenolic Profiles and Antioxidant Activity of Litchi Pericarp
Authors: Deng Mei , Deng Yuanyuan , Dong Lihong , Ma Yongxuan , Liu Lei , Huang Fei , Wei Zhencheng , Zhang Yan , Zhang Mingwei , Zhang Ruifen
Published: September 2018

Changes of phenolic profiles and antioxidant activity of litchi pericarp during storage at 4 °C for seven days and at room temperature (RT) for 72 h were evaluated in this study. The contents of total phenolic and procyanidin decreased by 20.2% and 24.2% at 4 °C and by 37.8% and 47.8% at RT, respectively. Interestingly, the corresponding reductions of anthocyanins were 41.3% and 73%, respectively. Four phenolic compounds, including epicatechin, procyanidin A2, procyanidin B2, and quercetin-3-O-rutinoside-7-O-α-l-rhamnosidase were detected in litchi pericarp. Their contents after storage at 4 °C and at RT were decreased by 22.1–49.7% and 27.6–48.7%, respectively. The oxygen radical absorbance capacity (ORAC) and cellular antioxidant activity (CAA) of litchi pericarp decreased by 17.6% and 58.7% at 4 °C, and by 23.4% and 66.0% at RT, respectively. The results indicated that storage at 4 °C preserved more phenolics and retained higher antioxidant activity in litchi pericarp compared to storage at RT, suggesting that storage at 4 °C should be considered as a more effective method for slowing down the degradation of litchi pericarp phenolics.
Synthesis and Characterization of Bis[1]benzothieno[3,2-b:2′,3′-d]pyrroles: Quantitative Effects of Benzannulation on Dithieno[3,2-b:2′,3′-d]pyrroles
Authors: Wolfe Rylan , Culver Evan , Rasmussen Seth
Published: September 2018

The synthesis of four N-functionalized bis[1]benzothieno[3,2-b:2′,3′-d]pyrroles (BBTPs) is reported in order to provide a more detailed characterization of these fused-ring units, as well as increase the scope of known BBTP units available for application to conjugated materials. The optical, electronic, and structural properties of the resulting BBTP units have been compared to the parent N-alkyl- and N-aryl-dithieno[3,2-b:2′,3′-d]pyrroles (DTPs), as well as their corresponding 2,6-diphenyl derivatives, in order to fully quantify the relative electronic effects resulting from benzannulation of the parent DTP building block. Such comparative analysis reveals that benzannulation results in a red-shifted absorbance, but to a lesser extent than simple phenyl-capping of the DTP. More surprising is that benzannulation results in stabilization of the BBTP HOMO, compared to the destabilization normally observed with extending the conjugation length of the backbone.
Tangible Representational Properties: Implications for Meaning Making
Authors: Pontual Falcão Taciana
Published: September 2018

Tangible technologies are considered promising tools for learning, by enabling multimodal interaction through physical action and manipulation of physical and digital elements, thus facilitating representational concrete–abstract links. A key concept in a tangible system is that its physical components are objects of interest, with associated meanings relevant to the context. Tangible technologies are said to provide ‘natural’ mappings that employ spatial analogies and adhere to cultural standards, capitalising on people’s familiarity with the physical world. Students with intellectual disabilities particularly benefit from interaction with tangibles, given their difficulties with perception and abstraction. However, symbolic information does not always have an obvious physical equivalent, and meanings do not reside in the representations used in the artefacts themselves, but in the ways they are manipulated and interpreted. In educational contexts, meaning attached to artefacts by designers is not necessarily transparent to students, nor interpreted by them as the designer predicted. Using artefacts and understanding their significance is of utmost importance for the construction of knowledge within the learning process; hence the need to study the use of the artefacts in contexts of practice and how they are transformed by the students. This article discusses how children with intellectual disabilities conceptually interpreted the elements of four tangible artefacts, and which characteristics of these tangibles were key for productive, multimodal interaction, thus potentially guiding designers and educators. Analysis shows the importance of designing physical-digital semantic mappings that capitalise on conceptual metaphors related to children’s familiar contexts, rather than using more abstract representations. Such metaphorical connections, preferably building on physical properties, contribute to children’s comprehension and facilitate their exploration of the systems.
A Comparative Study of Magnetic Properties of Large Diameter Co Nanowires and Nanotubes
Authors: Fernandez-Roldan Jose Angel , Chrischon Dieivase , Dorneles Lucio Strazzabosco , Chubykalo-Fesenko Oksana , Vazquez Manuel , Bran Cristina
Published: September 2018

A comparative study of the magnetic properties of the arrays of Co nanowires and nanotubes with large external diameters (180 nm) has been carried out. The nanowires/nanotubes were grown by electrodeposition into the self-assembled pores of anodic alumina membranes. The experimental study of their magnetic behavior was focused on the angular dependence of hysteresis loops and their parameters. In both nanowire and nanotube arrays, from the analysis of experimental data, effective longitudinal magnetic anisotropy is concluded, which is stronger in the case of the nanotube array. In addition, the extremely small remanence observed for all loops indicates the important role played by magnetostatic interactions. Micromagnetic simulations were first performed considering intrinsic shape and magnetocrystalline anisotropy terms, together with an effective easy-plane anisotropy to account for those magnetostatic interactions. A qualitative agreement between experiments and simulations is found despite the complexity introduced by the intrinsic and extrinsic array properties (i.e., large diameters, grain structure, and array configuration). In addition, simulations were also carried out for individual nanowire/nanotube with a particular emphasis to understand their differences at the remanence, due to pure geometry contribution.
Z Probe, An Efficient Tool for Characterizing Long Non-Coding RNA in FFPE Tissues
Authors: Tripathi Manish K. , Zacheaus Chidi , Doxtater Kyle , Keramatnia Fatemeh , Gao Cuilan , Yallapu Murali M. , Jaggi Meena , Chauhan Subhash C.
Published: September 2018

Formalin-fixed paraffin embedded (FFPE) tissues are a valuable resource for biomarker discovery in order to understand the etiology of different cancers and many other diseases. Proteins are the biomarkers of interest with respect to FFPE tissues as RNA degradation is the major challenge in these tissue samples. Recently, non-protein coding transcripts, long non-coding RNAs (lncRNAs), have gained significant attention due to their important biological actions and potential involvement in cancer. RNA sequencing (RNA-seq) or quantitative reverse transcription-polymerase chain reaction (qRT-PCR) are the only validated methods to evaluate and study lncRNA expression and neither of them provides visual representation as immunohistochemistry (IHC) provides for proteins. We have standardized and are reporting a sensitive Z probe based in situ hybridization method to visually identify and quantify lncRNA in FFPE tissues. This assay is highly sensitive and identifies transcripts visible within different cell types and tumors. We have detected a scarcely expressed tumor suppressor lncRNA NRON (non-coding repressor of nuclear factor of activated T-cells (NFAT)), a moderately expressed oncogenic lncRNA UCA1 (urothelial cancer associated 1), and a highly studied and expressed lncRNA MALAT1 (metastasis associated lung adenocarcinoma transcript 1) in different cancers. High MALAT1 staining was found in colorectal, breast and pancreatic cancer. Additionally, we have observed an increase in MALAT1 expression in different stages of colorectal cancer.
Concentration of Lactoferrin in Human Milk and Its Variation during Lactation in Different Chinese Populations
Authors: Yang Zhenyu , Jiang Rulan , Chen Qi , Wang Jie , Duan Yifan , Pang Xuehong , Jiang Shan , Bi Ye , Zhang Huanmei , Lönnerdal Bo , Lai Jianqiang , Yin Shian
Published: September 2018

Background: Lactoferrin (Lf) is a multifunctional protein and one of the most abundant proteins in human milk. Various factors may affect its concentration in human milk, such as stage of lactation, ethnicity, and diet. Objectives: The objectives of the present study were to examine the dynamic change in milk Lf throughout the course of lactation and explore factors associated with milk Lf concentrations in various Chinese populations. Methods: This investigation was a part of a large cross-sectional study conducted in 11 provinces/autonomous regions/municipalities (Beijing, Gansu, Guangdong, Guangxi, Heilongjiang, Inner Mongolia, Shandong, Shanghai, Xinjiang, Yunnan, and Zhejiang) across China between 2011 and 2013. Lactating women (n = 6481) within 0–330 days postpartum were recruited in the original study. A sub-sample of 824 women was randomly selected, and milk Lf concentrations were determined by UPLC/MS. Results: The Lf concentration in milk from women delivering at term was 3.16 g/L, 1.73 g/L and 0.90 g/L for colostrum, transitional milk, and mature milk, respectively. Lf concentrations differed significantly between stages of lactation (colostrum vs. transitional milk, colostrum vs. mature milk, transitional milk vs. mature milk, all p < 0.001). Maternal BMI, age, mode of delivery, parturition, protein intake, and serum albumin concentration were not correlated with milk Lf concentration. However, milk Lf concentrations varied among different geographical regions (Guangdong (1.91 g/L) vs. Heilongjiang (1.44 g/L), p = 0.037; Guangdong (1.91 g/L) vs. Gansu (1.43 g/L), p = 0.041) and ethnicities (Dai (1.80 g/L) vs. Tibetan (0.99 g/L), p = 0.007; Han (1.62 g/L) vs. Tibetan (0.99 g/L), p = 0.002) in China. Conclusions: The concentration of Lf in human milk changes dynamically throughout lactation. Few maternal characteristics affect the milk Lf concentration, but it varies across different geographical regions and ethnicities in China.
Effects of Inflammation on Biomarkers of Vitamin A Status among a Cohort of Bolivian Infants
Authors: Burke Rachel M. , Whitehead Ralph D. , Figueroa Janet , Whelan Denis , Aceituno Anna M. , Rebolledo Paulina A. , Revollo Rita , Leon Juan S. , Suchdev Parminder S.
Published: September 2018

Globally, vitamin A deficiency (VAD) affects nearly 200 million children with negative health consequences. VAD can be measured by a retinol-binding protein (RBP) and serum retinol concentrations. Their concentrations are not always present in a 1:1 molar ratio and are affected by inflammation. This study sought to quantify VAD and its impact on infant mortality and infectious morbidity during the first 18 months of life in a cohort of mother-infant dyads in El Alto, Bolivia, while accounting for the previously mentioned measurement issues. Healthy mother-infant dyads (n = 461) were enrolled from two hospitals and followed for 12 to 18 months. Three serum samples were collected (at one to two, six to eight, and 12 to 18 months of infant age) and analyzed for RBP, and a random 10% subsample was analyzed for retinol. Linear regression of RBP on retinol was used to generate RBP cut-offs equivalent to retinol <0.7 µmol/L. All measures of RBP and retinol were adjusted for inflammation, which was measured by a C-reactive protein and alpha (1)-acid glycoprotein serum concentrations using linear regression. Infant mortality and morbidity rates were calculated and compared by early VAD status at two months of age. Retinol and RBP were weakly affected by inflammation. This association varied with infant age. Estimated VAD (RBP < 0.7 µmol/L) decreased from 71.0% to 14.8% to 7.7% at two, six to eight, and 12 to 18 months of age. VAD was almost nonexistent in mothers. Early VAD was not significantly associated with infant mortality or morbidity rates. This study confirmed a relationship between inflammation and vitamin A biomarkers for some subsets of the population and suggested that the vitamin A status in early infancy improves with age and may not have significantly affected morbidity in this population of healthy infants.
Foods Contributing to Macronutrient Intake of Women Living in Puerto Rico Reflect Both Traditional Puerto Rican and Western-Type Diets
Authors: Truesdell Emily , Schelske-Santos Michelle , Nazario Cruz María , Rosario-Rosado Rosa V. , McCann Susan E. , Millen Amy E. , Ramírez-Marrero Farah A. , Freudenheim Jo L.
Published: September 2018

Lack of variability in dietary intake within a population makes identification of relationships between diet and disease difficult. Studies in populations with greater interindividual variation can provide important insights. The Puerto Rican diet is in transition from a traditional to a more Western-type diet, resulting in greater interindividual variability. We identified foods contributing to absolute intake and variability in the intake of macronutrients among Puerto Rican women. One hundred women, aged 30–79, residents of San Juan, Puerto Rico, completed three, interviewer-administered, 24-h dietary recalls from which foods contributing to absolute intake and intake variability in intake of energy, fat, protein, carbohydrate and dietary fiber were determined. The overall prevalence of intake of foods was also calculated. Traditional Puerto Rican foods such as legumes, rice, and plantains were important contributors to the intake of calories and macronutrients as were foods more typical of Western diets including white bread and sweetened carbonated beverages. Identification of food sources of nutrients for this population with a diet in transition can contribute to the development of instruments to measure dietary intake and to understand the contribution of diet to the etiology of chronic disease among Puerto Rican women.
Serum Parathyroid Hormone, 25-Hydroxyvitamin D, and Risk of Alzheimer’s Disease: A Mendelian Randomization Study
Authors: Larsson Susanna C. , Traylor Matthew , Markus Hugh S. , Michaëlsson Karl
Published: September 2018

We conducted Mendelian randomization analyses to investigate the associations of serum parathyroid hormone (S-PTH) and serum 25-hydroxyvitamin D (S-25OHD) concentrations with Alzheimer’s disease (AD). Five and seven single nucleotide polymorphisms associated with S-PTH and S-25OHD concentrations, respectively, were used as instrumental variables. Data for AD were acquired from the International Genomics of Alzheimer’s Project (17,008 AD cases and 37,154 controls). Genetically higher S-PTH concentrations were not associated with AD (odds ratio per standard deviation increase in S-PTH = 1.11; 95% CI 0.97–1.26; p = 0.12). In contrast, all seven 25OHD-increasing alleles were inversely associated with AD and two of the associations were statistically significant (p < 0.05). The odds ratio of AD per genetically-predicted one standard deviation increase in S-25OHD was 0.86 (95% CI 0.78–0.94; p = 0.002). This study provides evidence that vitamin D may play a role in AD but found no significant association between S-PTH and AD.
Dietary Interventions for the Prevention of Type 2 Diabetes in High-Risk Groups: Current State of Evidence and Future Research Needs
Authors: Guess Nicola D.
Published: September 2018

A series of large-scale randomised controlled trials have demonstrated the effectiveness of lifestyle change in preventing type 2 diabetes in people with impaired glucose tolerance. Participants in these trials consumed a low-fat diet, lost a moderate amount of weight and/or increased their physical activity. Weight loss appears to be the primary driver of type 2 diabetes risk reduction, with individual dietary components playing a minor role. The effect of weight loss via other dietary approaches, such as low-carbohydrate diets, a Mediterranean dietary pattern, intermittent fasting or very-low-energy diets, on the incidence of type 2 diabetes has not been tested. These diets—as described here—could be equally, if not more effective in preventing type 2 diabetes than the tested low-fat diet, and if so, would increase choice for patients. There is also a need to understand the effect of foods and diets on beta-cell function, as the available evidence suggests moderate weight loss, as achieved in the diabetes prevention trials, improves insulin sensitivity but not beta-cell function. Finally, prediabetes is an umbrella term for different prediabetic states, each with distinct underlying pathophysiology. The limited data available question whether moderate weight loss is effective at preventing type 2 diabetes in each of the prediabetes subtypes.
Short-Term Fish Oil Treatment Changes the Composition of Phospholipids While Not Affecting the Expression of Mfsd2a Omega-3 Transporter in the Brain and Liver of the 5xFAD Mouse Model of Alzheimer’s Disease
Authors: Milanovic Desanka , Petrovic Snjezana , Brkic Marjana , Avramovic Vladimir , Perovic Milka , Ivkovic Sanja , Glibetic Marija , Kanazir Selma
Published: September 2018

Long-term fish oil (FO) supplementation is able to improve Alzheimer’s disease (AD) pathology. We aimed to determine the impact of short-term fish oil (FO) intake on phospholipids composition and plaque pathology in 5xFAD mice, a widely used animal model of AD. A 3-week-long FO supplementation administered at 3 months of age decreased the number of dense core plaques in the 5xFAD cortex and changed phospholipids in the livers and brains of wild-type (Wt) and 5xFAD mice. Livers of both genotypes responded by increase of n-3 and reciprocal decrease of n-6 fatty acids. In Wt brains, FO supplementation induced elevation of n-3 fatty acids and subsequent enhancement of n-6/n-3 ratio. However, in 5xFAD brains the improved n-6/n-3 ratio was mainly due to FO-induced decrease in arachidonic and adrenic n-6 fatty acids. Also, brain and liver abundance of n-3 fatty acids were strongly correlated in Wts, oppositely to 5xFADs where significant brain-liver correlation exists only for n-6 fatty acids. Expression of omega-3 transporter Mfs2a remained unchanged after FO supplementation. We have demonstrated that even a short-term FO intake improves the phospholipid composition and has a significant effect on plaque burden in 5xFAD brains when applied in early stages of AD pathology.
Maternal Stress Potentiates the Effect of an Inflammatory Diet in Pregnancy on Maternal Concentrations of Tumor Necrosis Factor Alpha
Authors: Lindsay Karen L. , Buss Claudia , Wadhwa Pathik D. , Entringer Sonja
Published: September 2018

Maternal inflammation during pregnancy is known to adversely impact fetal development, birth outcomes, and offspring physical and mental health. Diet and stress have been identified as important determinants of inflammation, yet their combined effects have not been examined in the context of pregnancy. The aim of this study was to examine the relationship between maternal diet with inflammatory potential and psychological stress, and to determine their interaction effect on concentrations of tumor necrosis factor (TNF)-α across pregnancy. We conducted a prospective longitudinal study of n = 202 women with three assessments during pregnancy, which included: ecological momentary assessment (EMA) of maternal stress using the perceived stress scale (PSS) short version; 24-h dietary recalls from which the dietary inflammatory index (DII) was computed; and serum measurements of TNF-α. Across pregnancy, higher perceived stress was associated with consumption of a more pro-inflammatory diet (r = 0.137; p < 0.05). In a linear regression model adjusted for covariates, DII was positively associated with TNF-α (B = 0.093, p = 0.010). The effect of the pro-inflammatory diet on concentrations of TNF-α was more pronounced in women reporting higher levels of stress (B = 0.134, p = 0.018 for DII*PSS interaction). These results highlight the need to consider nutrition and stress concurrently in the context of inflammation during pregnancy.
Morphology and Thermal Properties of Calcium Alginate/Reduced Graphene Oxide Composites
Authors: Zhao Wanting , Qi Yan , Wang Yue , Xue Yun , Xu Peng , Li Zichao , Li Qun
Published: September 2018

Calcium alginate (CaAlg) is a kind of biodegradable and eco-friendly functional material, and CaAlg/reduced graphene oxide (rGO) composites are expected to be applied as new textile, heat-generating, and flame-retardant materials. In this paper, the CaAlg/rGO composites were prepared by a sol-gel method and their morphological and thermal properties were studied. The results showed that the introduction of rGO can efficiently improve the thermal stability of CaAlg. Further study showed that rGO increased the carbon formation rate by 4.1%, indicating that the thermal stability was improved by the promotion of carbon formation. Moreover, the weight loss rate of the composites was faster at 180–200 °C than that of CaAlg, after which the rate was less comparatively, suggesting the better thermal stability of the composite. This maybe because the high heat transfer efficiency of rGO allowed the material to reach the temperature of the thermal decomposition of the glycan molecule chain within a short time, and then promoted carbon formation. The thermal cracking mechanism of the composites is proposed based on the experimental data.
Rhodamine-Functionalized Mechanochromic and Mechanofluorescent Hydrogels with Enhanced Mechanoresponsive Sensitivity
Authors: Wang Lijun , Zhou Wanfu , Tang Quan , Yang Haiyang , Zhou Qiang , Zhang Xingyuan
Published: September 2018

Smart materials responsible to external stimuli such as temperature, pH, solvents, light, redox agents, and mechanical or electric/magnetic field, have drawn considerable attention recently. Herein, we described a novel rhodamine (Rh) mechanophore-based mechanoresponsive micellar hydrogel with excellent mechanochromic and mechanofluorescent properties. We found with astonishment that, due to the favorable activation of rhodamine spirolactam in the presence of water, together with the stress concentration effect, the mechanoresponsive sensitivity of this hydrogel was enhanced significantly. As a result, the stress needed to trigger the mechanochromic property of Rh in the hydrogel was much lower than in its native polymer matrix reported before. The hydrogel based on Rh, therefore, exhibited excellent mechanochromic property even at lower stress. Moreover, due to the reversibility of color on/off, the hydrogel based on Rh could be used as a reusable and erasable material for color printing/writing. Of peculiar importance is that the hydrogel could emit highly bright fluorescence under sufficient stress or strain. This suggested that the stress/strain of hydrogel could be detected quantificationally and effectively by the fluorescence data. We also found that the hydrogel could respond to acid/alkali and exhibited outstanding properties of acidichromism and acidifluorochromism. Up to now, hydrogels with such excellent mechanochromic and mechanofluorescent properties have rarely been reported. Our efforts may be essentially beneficial to the design of the mechanochromic and mechanofluorescent hydrogels with enhanced mechanoresponsive sensitivity, fostering their potential applications in a number of fields such as damage or stress/strain detection.
Temporal Mixing Behavior of Conservative Solute Transport through 2D Self-Affine Fractures
Authors: Dou Zhi , Sleep Brent , Mondal Pulin , Guo Qiaona , Wang Jingou , Zhou Zhifang
Published: September 2018

In this work, the influence of the Hurst exponent and Peclet number (Pe) on the temporal mixing behavior of a conservative solute in the self-affine fractures with variable-aperture fracture and constant-aperture distributions were investigated. The mixing was quantified by the scalar dissipation rate (SDR) in fractures. The investigation shows that the variable-aperture distribution leads to local fluctuation of the temporal evolution of the SDR, whereas the temporal evolution of the SDR in the constant-aperture fractures is smoothly decreasing as a power-law function of time. The Peclet number plays a dominant role in the temporal evolution of mixing in both variable-aperture and constant-aperture fractures. In the constant-aperture fracture, the influence of Hurst exponent on the temporal evolution of the SDR becomes negligible when the Peclet number is relatively small. The longitudinal SDR can be related to the global SDR in the constant-aperture fracture when the Peclet number is relatively small. As the Peclet number increases the longitudinal SDR overpredicts the global SDR. In the variable-aperture fractures, predicting the global SDR from the longitudinal SDR is inappropriate due to the non-monotonic increase of the longitudinal concentration second moment, which results in a physically meaningless SDR.
Effect of the Length-to-Width Aspect Ratio of a Cuboid Packed-Bed Device on Efficiency of Chromatographic Separation
Authors: Chen Guoqiang , Ghosh Raja
Published: September 2018

In recent papers we have discussed the use of cuboid packed-bed devices as alternative to columns for chromatographic separations. These devices address some of the major flow distribution challenges faced by preparative columns used for process-scale purification of biologicals. Our previous studies showed that significant improvements in separation metrics such as the number of theoretical plates, peak shape, and peak resolution in multi-protein separation could be achieved. However, the length-to-width aspect ratio of a cuboid packed-bed device could potentially affect its performance. A systematic comparison of six cuboid packed-bed devices having different length-to-width aspect ratios showed that it had a significant effect on separation performance. The number of theoretical plates per meter in the best-performing cuboid packed-bed device was about 4.5 times higher than that in its equivalent commercial column. On the other hand, the corresponding number in the worst-performing cuboid-packed bed was lower than that in the column. A head-to-head comparison of the best-performing cuboid packed bed and its equivalent column was carried out. Performance metrics compared included the widths and dispersion indices of flow-through and eluted protein peaks. The optimized cuboid packed-bed device significantly outperformed its equivalent column with regards to all these attributes.
Barriers to Household Waste Recycling: Empirical Evidence from South Africa
Authors: Strydom Wilma F.
Published: September 2018

A small percentage of South Africans regularly recycle most of their recyclables, which was only 4% and 7.2% in 2010 and 2015, respectively. This empirical quantitative study, the first study on this scale in South Africa, aimed to ascertain the reasons why people do not recycle. This paper reports the results from a survey conducted among a representative sample of 2004 respondents in eleven of South Africa’s large urban areas. Each respondent selected three main reasons why people do not recycle from ten possible options as well as the one main reason. The results show that (i) insufficient space, (ii) no time, (iii) dirty and untidiness associated with recycling, (iv) lack of recycling knowledge, and (v) inconvenient recycling facilities are perceived as the main reasons why people do not recycle. Non-recycling households (74% of the respondents) give high priority to time and knowledge. Low recyclers—those that sporadically recycle few items—and young South Africans give high priority to services (inconvenient facilities and no curbside collection). Lack of knowledge is an important factor for people from dense settlements as well as the unemployed looking for work. Improved recycling services such as regular curbside collections have the potential to overcome time and space barriers. Recycling services as well as recycling knowledge will have to improve to encourage the youth, the unemployed, and those living in informal areas to recycle and realize the opportunities locked in the waste sector. The perceptions of respondents from non-recycling households differ from those from recycling households. The larger representation of non-recyclers in developing countries emphasize the importance of understanding local evidence when comparing and implementing results from developed countries. The learning from this study could also assist other developing countries to encourage household participation in recycling initiatives.
Stability and Gait Planning of 3-UPU Hexapod Walking Robot
Authors: Li Ruiqin , Meng Hongwei , Bai Shaoping , Yao Yinyin , Zhang Jianwei
Published: September 2018

The paper presents an innovative hexapod walking robot built with 3-UPU parallel mechanism. In the robot, the parallel mechanism is used as both an actuator to generate walking and also a connecting body to connect two groups of three legs, thus enabling the robot to walk with simple gait by very few motors. In this paper, forward and inverse kinematics solutions are obtained. The workspace of the parallel mechanism is analyzed using limit boundary search method. The walking stability of the robot is analyzed, which yields the robot’s maximum step length. The gait planning of the hexapod walking robot is studied for walking on both flat and uneven terrains. The new robot, combining the advantages of parallel robot and walking robot, has a large carrying capacity, strong passing ability, flexible turning ability, and simple gait control for its deployment for uneven terrains.
Validation of Aerosol Products from AATSR and MERIS/AATSR Synergy Algorithms—Part 1: Global Evaluation
Authors: Che Yahui , Mei Linlu , Xue Yong , Guang Jie , She Lu , Li Ying , Heckel Andreas , North Peter
Published: September 2018

The European Space Agency’s (ESA’s) Aerosol Climate Change Initiative (CCI) project intends to exploit the robust, long-term, global aerosol optical thickness (AOT) dataset from Europe’s satellite observations. Newly released Swansea University (SU) aerosol products include ATSR-2 (1995-2003) and AATSR(2002-2012) retrieval with a spatial resolution of 10 km. Recently an experimental version of a retrieval using AATSR/MERIS synergy was developed to provide four months of data for initial testing. In this study, both AATSR retrieval (SU/AATSR) and AATSR/MERIS synergy retrieval (SU/synergy) datasets are validated globally using Aerosol Robotic Network (AERONET) observations for March, June, September, and December 2008, as suggested by the Aerosol-CCI project. The analysis includes the impacts of cloud screening, surface parameterization, and aerosol type selections for two datasets under different surface and atmospheric conditions. The comparison between SU/AATSR and SU/synergy shows very accurate and consistent global patterns. The global evaluation using AERONET shows that the SU/AATSR product exhibits slightly better agreement with AERONET than the SU/synergy product. SU/synergy retrieval overestimates AOT for all surface and aerosol conditions. SU/AATSR data is much more stable and has better quality; it slightly underestimates fine-mode dominated and absorbing AOTs yet slightly overestimates coarse-mode dominated and non-absorbing AOTs.
Ultra-Wideband (UWB) Antenna Sensor Based Microwave Breast Imaging: A Review
Authors: Mahmud Md. Zulfiker , Islam Mohammad Tariqul , Misran Norbahiah , Almutairi Ali F. , Cho Mengu
Published: September 2018

Globally, breast cancer is reported as a primary cause of death in women. More than 1.8 million new breast cancer cases are diagnosed every year. Because of the current limitations on clinical imaging, researchers are motivated to investigate complementary tools and alternatives to available techniques for detecting breast cancer in earlier stages. This article presents a review of concepts and electromagnetic techniques for microwave breast imaging. More specifically, this work reviews ultra-wideband (UWB) antenna sensors and their current applications in medical imaging, leading to breast imaging. We review the use of UWB sensor based microwave energy in various imaging applications for breast tumor related diseases, tumor detection, and breast tumor detection. In microwave imaging, the back-scattered signals radiating by sensors from a human body are analyzed for changes in the electrical properties of tissues. Tumorous cells exhibit higher dielectric constants because of their high water content. The goal of this article is to provide microwave researchers with in-depth information on electromagnetic techniques for microwave imaging sensors and describe recent developments in these techniques.
An Autonomous Vehicle Navigation System Based on Inertial and Visual Sensors
Authors: Guang Xingxing , Gao Yanbin , Leung Henry , Liu Pan , Li Guangchun
Published: September 2018

The strapdown inertial navigation system (SINS) is widely used in autonomous vehicles. However, the random drift error of gyroscope leads to serious accumulated navigation errors during long continuous operation of SINS alone. In this paper, we propose to combine the Inertial Measurement Unit (IMU) data with the line feature parameters from a camera to improve the navigation accuracy. The proposed method can also maintain the autonomy of the navigation system. Experimental results show that the proposed inertial-visual navigation system can mitigate the SINS drift and improve the accuracy, stability, and reliability of the navigation system.