bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of Polymethylsilsesquioxane Content to the Thermal Stability of Meta-Aramid Fiber Insulation Paper
Authors: Zheng Wei , Xie Jufang , Zhang Jingwen , Tang Chao , Zhao Zhongyong
Published: November 2018

Polymethylsilsesquioxane (PMSQ) nanoparticles with mass percentages of 0, 2.5, 5.0, 7.2, 9.4 wt %, respectively, were constructed by molecular dynamics methods in this paper. Composite molecular models were established using PMSQ and MPIA (poly-metaphenylene isophthalamide) fiber. The influence of different PMSQ contents on the thermal stability of meta-aramid insulation paper was analyzed from the parameters of mechanical property, interaction energy, and mean square displacement. The results showed that the trend of mechanical properties decreased with the increase of PMSQ content. When the PMSQ content was 2.5 wt %, the mechanical properties of the composited model were the best, which was about 24% higher than that of the unmodified model. From an intermolecular bonding and nonbonding point of view, the energy parameters of composite model with the 2.5 wt % content was better than those of the composite model with other contents. Therefore, it is considered that MPIA can interact better with the 2.5 wt % content PMSQ composite model. When the PMSQ content is 2.5 wt %, the overall chain movement in the composite model is slower than that of the unmodified model, which can effectively inhibit the diffusion movement of the MPIA chain. In general, the thermal stability of composite molecular models MPIA and PMSQ (2.5 wt %) was better improved.
Preparation of Assembled Carbon Soot Films and Hydrophobic Properties
Authors: Zhao Lei , Zhao Kang , Yan Wei-Guo , Liu Zhifeng
Published: November 2018

In this paper, a simple, inexpensive, and rapid method for the fabrication of controlled layer candle soot film has been reported by interface self-assembly and transferred method. The mechanism of candle soot self-assembly is explained and their morphology, elemental composition, optical, and wetting properties are characterized. The uniformity and thickness of prepared films especially depend on the concentration of candle soot mixed solution (alcohol and deionized water). The results show that the optimal concentration of candle soot solution is approximately ~0.2% wt/mL. In addition, the absorption spectra of the controlled-layer candle soot films are determined by the number of layers and the surface morphology. The hydrophobic properties of candle soot films are closely related to their layer number. When these films reach to the fourth layer, the water contact angle and roll-off angle are measured as 142° ± 2° and 6°, respectively. The controlled assembly CS films have the potential application in photo/electrocatalysis, solar cells, lithium-ion batteries, and water splitting.
Model Establishment of a Co-Based Metal Matrix with Additives of WC and Ni by Discrete Element Method
Authors: Chen Xiuyu , Huang Guoqin , Tan Yuanqiang , Huang Hui , Guo Hua , Xu Xipeng
Published: November 2018

A metal matrix is an indispensable component of metal-bonded diamond tools. The composition design of a metal matrix involves a number of experiments, making costly in terms of time, labor, and expense. The discrete element method (DEM) is a potential way to relieve these costs. The aim of this work is to demonstrate a methodology for establishing and calibrating metal matrix’s DEM model. A Co-based metal matrix with WC and Ni additives (CoX–WC–Ni) was used, in which the Co-based metal was Co–Cu–Sn metal (CoX). The skeletal substances in the metal matrix were treated as particles in the model, and the bonding substances were represented by the parallel bond between particles. To describe the elasticity of the metal matrix, a contact bond was also loaded between particles. A step-by-step calibration procedure with experimental tests of three-point bending and compression was proposed to calibrate all microcosmic parameters involved during the establishment of DEM models: first for the CoX matrix, then for the CoX–WC matrix and CoX–Ni matrix, and finally for the CoX–WC–Ni matrix. The CoX–WC–Ni DEM model was validated by the transverse rupture strength (TRS) of two new compositions and the results indicated that the model exhibited a satisfactory prediction ability with an error rate of less than 10%.
Equivalent Properties of Transition Layer Based on Element Distribution in Laser Bending of 304 Stainless Steel/Q235 Carbon Steel Laminated Plate
Authors: Li Zihui , Wang Xuyue , Luo Yonghao
Published: November 2018

Compared with the single-component metal plate, there is a special transition layer on the joint interface between two kinds of materials in the stainless steel-carbon steel laminated plate (SCLP). In order to describe the finite element model of laser bending accurately, it is of great significance to determine material properties of the transition layer. Based on the element distribution, an equivalent method is adopted to calculate thermal conductivity, thermal expansion coefficient, elastic modulus, density, Poisson’s ratio, and specific heat capacity of transition layer. The electron probe experiments show that the transition layer is formed by interfacial element diffusion with thickness of 7 μm. Besides, the volume fraction of stainless steel (46.63%) and carbon steel (53.37%) in the transition layer is tested by energy dispersive spectrometer, respectively. Through the equivalent method, a laser bending model of SCLP is simulated by ANSYS software to predict the bending angle under different parameters. The experimental verification shows that the maximum of bending angle errors is 3.74%, which is lower than the maximum 4.93% of errors calculated by the mean value method. The analysis verifies that the laser bending model is feasible and contributes to improving the accuracy of modeling SCLP in the laser bending process.
Inequalities on Sasakian Statistical Manifolds in Terms of Casorati Curvatures
Authors: Lee Chul Woo , Lee Jae Won
Published: November 2018

A statistical structure is considered as a generalization of a pair of a Riemannian metric and its Levi-Civita connection. With a pair of conjugate connections ∇ and ∇ * in the Sasakian statistical structure, we provide the normalized scalar curvature which is bounded above from Casorati curvatures on C-totally real (Legendrian and slant) submanifolds of a Sasakian statistical manifold of constant φ -sectional curvature. In addition, we give examples to show that the total space is a sphere.
Ball Convergence of an Efficient Eighth Order Iterative Method Under Weak Conditions
Authors: Sharma Janak Raj , Argyros Ioannis K. , Kumar Sunil
Published: November 2018

The convergence order of numerous iterative methods is obtained using derivatives of a higher order, although these derivatives are not involved in the methods. Therefore, these methods cannot be used to solve equations with functions that do not have such high-order derivatives, since their convergence is not guaranteed. The convergence in this paper is shown, relying only on the first derivative. That is how we expand the applicability of some popular methods.
Random Best Proximity Points for α-Admissible Mappings via Simulation Functions
Authors: Kongban Chayut , Kumam Poom , Martínez-Moreno Juan
Published: November 2018

In this paper, we introduce a new concept of random α -proximal admissible and random α - Z -contraction. Then we establish random best proximity point theorems for such mapping in complete separable metric spaces.
Tsallis Entropy of Fuzzy Dynamical Systems
Authors: Markechová Dagmar
Published: November 2018

This article deals with the mathematical modeling of Tsallis entropy in fuzzy dynamical systems. At first, the concepts of Tsallis entropy and Tsallis conditional entropy of order q , where q is a positive real number not equal to 1, of fuzzy partitions are introduced and their mathematical behavior is described. As an important result, we showed that the Tsallis entropy of fuzzy partitions of order q > 1 satisfies the property of sub-additivity. This property permits the definition of the Tsallis entropy of order q > 1 of a fuzzy dynamical system. It was shown that Tsallis entropy is an invariant under isomorphisms of fuzzy dynamical systems; thus, we acquired a tool for distinguishing some non-isomorphic fuzzy dynamical systems. Finally, we formulated a version of the Kolmogorov–Sinai theorem on generators for the case of the Tsallis entropy of a fuzzy dynamical system. The obtained results extend the results provided by Markechová and Riečan in Entropy, 2016, 18, 157, which are particularized to the case of logical entropy.
Preparation of Polybenzimidazole Hollow-Fiber Membranes for Reverse Osmosis and Nanofiltration by Changing the Spinning Air Gap
Authors: Wang Xiao , Jayaweera Palitha , Alrasheed Radwan , Aljlil Saad , Alyousef Yousef , Alsubaei Mohammad , AlRomaih Hamad , Jayaweera Indira
Published: November 2018

High-performance polybenzimidazole (PBI) hollow-fiber membranes (HFMs) were fabricated through a continuous dry-jet wet spinning process at SRI International. By adjusting the spinning air gap from 4″ (10.2 cm) to 0.5″ (1.3 cm), the HFM pore sizes were enlarged dramatically without any significant change of the fiber dimensional size and barrier layer thickness. When fabricated with an air gap of 2.5″ (6.4 cm) and a surface modified by NaClO solution, the PBI HFM performance was comparable to that of a commercial reverse osmosis (RO) HFM product from Toyobo in terms of salt (NaCl) rejection and water permeability. The PBI RO HFM was positively surface charged in acidic conditions (pH < 7), which enhanced salt rejection via the Donnan effect. With an air gap of 1.5″ (3.8 cm), the PBI HFM rejected MgSO4 and Na2SO4 above 95%, a result that compares favorably with that achieved by nanofiltration. In addition, the PBI HFM has a defect-free structure with an ultra-thin barrier layer and porous sublayer. We believe PBI HFMs are ideal for water purification and can be readily commercialized.
A Contribution for the Valorisation of Sheep and Goat Cheese Whey through Nanofiltration
Authors: Macedo Antónia , Monteiro Joana , Duarte Elizabeth
Published: November 2018

The amount of cheese whey generated from the production of speciality sheep and goat cheese is significantly growing due to the acclaimed nutritional and medicinal benefits of the milk from these species. However, most of the cheese whey generated has no applications, thus giving rise to environmental problems. This work focuses on the study of the performance of the nanofiltration process for recovering the permeates of ultrafiltration from sheep and goat cheese whey. Nanofiltration experiments were carried out with membranes of nanofiltration (NF) in total recirculation and concentration modes, at 25 °C. Nanofiltration of the ultrafiltration permeates from sheep cheese whey was done at a pressure of 3.0 × 106 Pa and a circulation velocity of 1.42 m·s−1, until a volume concentration factor (VCF) of 2.5. Nanofiltration of the permeates from ultrafiltration of goat cheese whey was performed at a pressure of 2.0 × 106 Pa and a circulation velocity of 0.94 m·s−1, until a VCF of 2.0. From the results, it was concluded that osmotic pressure was the most important factor affecting the performance of the process. In both cases, the final permeates had a much lower organic load and its future use in the process of cheese making should be evaluated.
Optimization of A354 Al-Si-Cu-Mg Alloy Heat Treatment: Effect on Microstructure, Hardness, and Tensile Properties of Peak Aged and Overaged Alloy
Authors: Toschi Stefania
Published: November 2018

The aim of the present work is the study of T6 heat treatment of A354 (Al-Si-Cu-Mg) casting alloy. The heat treatment was optimized by maximizing mechanical strength of the alloy while keeping the treatment cost effective, reducing treatment time and temperature. Due to the presence of low melting compounds, a double stage solution treatment was proposed. The first stage was aimed at the homogenization and dissolution of the low melting phase while a second stage at a higher temperature was evaluated to foster dissolution of Cu/Mg rich intermetallics and keep the solution time and temperature as low as possible. Microstructural investigations were performed through optical and electronic microscopy, which allowed the assessment of the evolution of intermetallic phases during the solution treatment. Artificial aging was studied at different temperatures from 160 °C to 210 °C where the peak aging condition was identified. Over aging of the heat treated alloy was evaluated by soaking T6 samples at 200, 245, and 290 °C for up to 168 h. Tensile behavior of the T6 and over-aged alloy (i.e., after soaking at 210 °C for 50 h) was evaluated at room temperature. Results showed that the proposed treatment allowed the enhancement of mechanical properties of the alloy in comparison to industrial practice treatment, maintaining a good level of ductility and conferring a superior resistance to long-term high temperature exposure.
Bainite and Martensite: Developments and Challenges
Authors: Garcia-Mateo Carlos
Published: November 2018

Both microstructures, martensite and bainite, although share some common features, when studied in further detail depict a plethora of subtle differences that make them unique. [...]
A Study on the Machining Characteristics of Curved Workpiece Using Laser-Assisted Milling with Different Tool Paths in Inconel 718
Authors: Kim Eun Jung , Lee Choon Man
Published: November 2018

Difficult-to-cut materials are being increasingly used in many industries because of their superior properties, including high corrosion resistance, heat resistance and specific strength. However, these same properties make the materials difficult to machine using conventional machining techniques. Laser-assisted milling (LAM) is one of the effective method for machining difficult-to-cut materials. In laser-assisted milling, the machining occur after the workpiece is locally preheated using a laser heat source. Laser-assisted milling has been studied by many researchers on flat workpiece or micro end-milling. However, there is no research on the curved shape using laser assisted milling. This study investigated the use of laser-assisted milling to machine a three-dimensional curved shape workpiece based on NURBS (Non-uniform rational b-spline). A machining experiment was performed on Inconel 718 using different tool paths (ramping, contouring) under various machining conditions. Finite elements analysis was conducted to determine the depth of cut. Cutting force, specific cutting energy and surface roughness characteristics were measured, analyzed and compared for conventional and LAM machining. LAM significantly improved these machining characteristics, compared to conventional machining. There results can be applied to the laser-assisted milling of various three-dimensional shapes.
Self-Renewal and Differentiation of Adipose-Derived Stem Cells (ADSCs) Stimulated by Multi-Axial Tensile Strain in a Pneumatic Microdevice
Authors: Chiu Chih-Hao , Tong Yun-Wen , Yeh Wen-Ling , Lei Kin Fong , Chen Alvin Chao-Yu
Published: November 2018

Adipose-derived stem cells (ADSCs) were suggested for treating degenerative osteoarthritis, suppressing inflammatory responses, and repairing damaged soft tissues. Moreover, the ADSCs have the potential to undergo self-renewal and differentiate into bone, tendon, cartilage, and ligament. Recently, investigation of the self-renewal and differentiation of the ADSCs has become an attractive area. In this work, a pneumatic microdevice has been developed to study the gene expression of the ADSCs after the stimulation of multi-axial tensile strain. The ADSCs were cultured on the microdevice and experienced multi-axial tensile strain during a three-day culture course. Self-renewal and differentiation abilities were investigated by mRNA expressions of NANOG, sex determining region Y-box 2 (SOX2), octamer-binding transcription factor 4 (OCT4), sex determining region Y-box9 (SOX9), peroxisome proliferator-activated receptor gamma (PPAR-γ), and runt-related transcription factor 2 (RUNX2). The result showed that the genes related self-renewal were significantly up-regulated after the tensile stimulation. Higher proliferation ratio of the ADSCs was also shown by cell viability assay. The microdevice provides a promising platform for cell-based study under mechanical tensile stimulation.
Underground Vertical Seismic Profiling with Conventional and Fiber-Optic Systems for Exploration in the Kylylahti Polymetallic Mine, Eastern Finland
Authors: Riedel Marko , Cosma Calin , Enescu Nicoleta , Koivisto Emilia , Komminaho Kari , Vaittinen Katri , Malinowski Michał
Published: November 2018

Seismic reflection methods have been used for the exploration of mineral resources for several decades. However, despite their unmatched spatial resolution and depth penetration, they only have played a minor role in mineral discoveries so far. Instead, mining and exploration companies have traditionally focused more on the use of potential field, electric and electromagnetic methods. In this context, we present a case study of an underground Vertical Seismic Profiling (VSP) experiment, which was designed to image a (semi-)massive sulfide deposit located in the Kylylahti polymetallic mine in eastern Finland. For the measurement, we used a conventional VSP with three-component geophones and a novel fiber-optic Distributed Acoustic Sensing (DAS) system. Both systems were deployed in boreholes located nearby the target sulfide deposit, and used in combination with an active seismic source that was fired from within the underground tunnels. With this setup, we successfully recorded seismic reflections from the deposit and its nearby geological contrasts. The recording systems provided data with a good signal-to-noise ratio and high spatial resolution. In addition to the measurements, we generated a realistic synthetic dataset based on a detailed geological model derived from extensive drilling data and petrophysical laboratory analysis. Specific processing and imaging of the acquired and synthetic datasets yielded high-resolution reflectivity images. Joint analysis of these images and cross-validation with lithological logging data from 135 nearby boreholes led to successful interpretation of key geological contacts including the target sulfide mineralization. In conclusion, our experiment demonstrates the value of in-mine VSP measurements for detailed resource delineation in a complex geological setting. In particular, we emphasize the potential benefit of using fiber-optic DAS systems, which provide reflection data at sufficient quality with less logistical effort and a higher acquisition rate. This amounts to a lower total acquisition cost, which makes DAS a valuable tool for future mineral exploration activities.
Implementation of a Single Quadrupole Mass Spectrometer for Fingerprint Analysis: Venenum bufonis as a Case Study
Authors: Wei Wenlong , Wang Xia , Hou Jinjun , Yao Changliang , Feng Zijin , Zhang Jianqing , Han Sumei , Deng Yanping , Huang Yong , Wu Wanying , Guo Dean
Published: November 2018

The mass spectrometry (MS) has been widely used for profiling chemical components of traditional Chinese medicine (TCM). However, there are few studies reporting quality control of TCM based on mass spectrometry fingerprint (MSF) due to its complicated operation and high cost. The aim of this study was to extend the application of MSF for quality evaluation of TCM. In this study, an MSF based on single quadrupole mass spectrometry method was established, and was successfully used for the quality control of Venenum bufonis (VB), a famous TCM which was used clinically for cancer treatment in China. The results showed that the superiority of MSF for more chemical information exposure and the finding of more potential chemical markers (eight versus four) compared with the traditional photo-diode array (a kind of ultra violet detector, PDA). Besides, the performance of MSF was also validated by similarity and principle component analysis (PCA) of MS data acquired on two other mass spectrometry (low-resolution, triple quadrupole, QQQ, and high-resolution, quadruple time-of-flight, Q-TOF), showing high consistency with QQQ and Q-TOF, but robustness with few parameters’ settings. Based on our study, MSF could be widely applied for the quality control of TCM.
Synthesis and Anticancer Activity Evaluation of Hydrolyzed Derivatives of Panaxnotoginseng Saponins
Authors: Xu Lei , Xiao Shengnan , Yuan Weihui , Cui Jiongmo , Su Guangyue , Zhao Yuqing
Published: November 2018

To increase the antitumor activity of ginsenosides and acetylsalicylic acid, acid hydrolysis products of Panaxnotoginseng saponin were used as raw materials to be combined with salicylic acid to obtain ginsenoside salicylic acid derivatives. All derivatives were assessed for anti-cancer activity. A total of 20 target compounds were designed and synthesized. The cytotoxic activity on five cancer cell lines, including human colon cancer (HT-29), gastric cancer (BGC-823), cervical cancer (Hela), human breast cancer (MCF-7), human lung cancer cells (A549), and two normal cancer cell lines (human gastric epithelial cells (GES-1), and human ovarian epithelial cells (IOSE144)) was evaluated following treatment with the compounds. The results showed that all compounds inhibited the growth of cancer cells. Compounds 1a, 3a, 7a, 1b, 2b, 3b and 8b showed strong anticancer activity. For MCF-7 cells, compound 3b showed the strongest inhibitory activity, IC50 = 2.56 ± 0.09 μM. In the cytotoxicity test, all compounds showed low toxicity or no toxicity (IC50 > 100 μM). In addition, a cell cycle distribution assay and wound healing assay demonstrated that compound 3b specifically inhibited MCF-7 proliferation and migration ability. Our results indicate that compound 3b represents a promising compound for further cancer studies.
Enhanced Electrocatalytic Activity and Stability toward the Oxygen Reduction Reaction with Unprotected Pt Nanoclusters
Authors: Liu Jing , Yin Jiao , Feng Bo , Xu Tao , Wang Fu
Published: November 2018

The Pt particles within diameters of 1–3 nm known as Pt nanoclusters (NCs) are widely considered to be satisfactory oxygen reduction reaction (ORR) catalysts due to higher electrocatalytic performance and cost effectiveness. However, the utilization of such smaller Pt NCs is always limited by the synthesis strategies, stability and methanol tolerance of Pt. Herein, unprotected Pt NCs (~2.2 nm) dispersed on carbon nanotubes (CNTs) were prepared via a modified top-down approach using liquid Li as a solvent to break down the bulk Pt. Compared with the commercial Pt/C, the resultant Pt NCs/CNTs catalyst (Pt loading: 10 wt.%) exhibited more desirable ORR catalytic performance in 0.1 M HClO4. The specific activity (SA) and mass activity (MA) at 0.9 V for ORR over Pt NCs/CNTs were 2.5 and 3.2 times higher than those over the commercial Pt/C (Pt loading: 20 wt.%). Meanwhile, the Pt NCs/CNTs catalyst demonstrated more satisfactory stability and methanol tolerance. Compared with the obvious loss (~69%) of commercial Pt/C, only a slight current decrease (~10%) was observed for Pt NCs/CNTs after the chronoamperometric measurement for 2 × 104 s. Hence, the as-prepared Pt NCs/CNTs material displays great potential as a practical ORR catalyst.
Inhibition Effect of Graphene on Space Charge Injection and Accumulation in Low-Density Polyethylene
Authors: Li Zhonglei , Su Jingang , Du Boxue , Hou Zhaohao , Han Chenlei
Published: November 2018

Space charge injection and accumulation is attracting much attention in the field of dielectric insulation especially for electronic devices, power equipment and so on. This paper proposes using the inhibition effect of graphene for the injection and accumulation of space charge in low-density polyethylene (LDPE). Scanning electron microscope (SEM) and transmission electron microscopy (TEM) images were employed to observe the dispersion of graphene with a two-dimensional structure in LDPE. The time-dependent space charge dynamic behaviors of graphene/LDPE nanocomposites with the filler content of 0, 0.003, 0.005, 0.007 and 0.01 wt % were characterized by the pulsed electro-acoustic (PEA) test at 40, 60 and 80 °C, and the charge mobility was evaluated by its depolarization processes. The experimental results show that for the undoped LDPE film, large amounts of space charges were injected from the electrodes into samples, especially at 60 and 80 °C. The graphene/LDPE nanocomposites with a filler content of 0.005 wt % could markedly suppress the space charge injection and accumulation even at 80 °C, which is attributed to the large quantities of graphene-polymer in interface regions. These interface regions introduced numbers of deep trap sites within the forbidden band of nanocomposites, which can reduce the de-trapping rate of charges and suppress the space charge accumulation in the polymer bulks. The graphene/LDPE nanocomposites are suggested for dielectric applications, intending the inhibition of space charge injection and accumulation.
A DFT Screening of M-HKUST-1 MOFs for Nitrogen-Containing Compounds Adsorption
Authors: Zong Shibiao , Zhang Yajing , Lu Na , Ma Pan , Wang Jianguo , Shi Xue-Rong
Published: November 2018

To develop promising adsorbent candidates for adsorptive denitrogenation, we screened the adsorption of NO, NO2, and NH3 in 19 M-HKUST-1 (M = Be, Fe, Ni, Cr, Co, Cu, V, Zn, Mo, Mn, W, Sn, Ti, Cd, Mg, Sc, Ca, Sr, and Ba) systematically using first-principle calculations. Of these, four variants of M-HKUST-1 (M = Ni, Co, V, and Sc) yield more negative adsorption Gibbs free energy ΔGads than the original Cu-HKUST-1 for three adsorbates, suggesting stronger adsorbate binding. Ti-HKUST-1, Sc-HKUST-1, and Be-HKUST-1 are predicted to have the largest NO, NO2, and NH3 adsorption energies within the screened M-HKUST-1 series, respectively. With the one exception of NO2 dissociation on V-HKUST-1, dissociative adsorption of NO, NO2, and NH3 molecules on the other considered M-HKUST-1 is energetically less favorable than molecular adsorption thermodynamically. The barrier calculations show that the dissociation is difficult to occur on Cu-HKUST-1 kinetically due to the very large dissociation barrier. Electronic analysis is provided to explain the bond nature between the adsorbates and M-HKUST-1. Note that the isostructural substitution of Cu to the other metals is a major simplification of the system, representing the ideal situation; however, the present study provides interesting targets for experimental synthesis and testing.
Direct and Long-Term Metabolic Consequences of Lowly vs. Highly-Digestible Starch in the Early Post-Weaning Diet of Mice
Authors: Fernández-Calleja José M. S. , Bouwman Lianne M. S. , Swarts Hans J. M. , Oosting Annemarie , Keijer Jaap , Van Schothorst Evert M.
Published: November 2018

Starches of low and high digestibility have different metabolic effects. Here, we examined whether this gives differential metabolic programming when fed in the immediate post-weaning period. Chow-fed mice were time-mated, and their nests were standardized and cross-fostered at postnatal days 1–2. After postnatal week (PW) 3, individually housed female and male offspring were switched to a lowly-digestible (LDD) or highly-digestible starch diet (HDD) for three weeks. All of the mice received the same high-fat diet (HFD) for nine weeks thereafter. Energy and substrate metabolism and carbohydrate fermentation were studied at the end of the HDD/LDD and HFD periods by extended indirect calorimetry. Glucose tolerance (PW 11) and metabolic flexibility (PW14) were analyzed. Directly in response to the LDD versus the HDD, females showed smaller adipocytes with less crown-like structures in gonadal white adipose tissue, while males had a lower fat mass and higher whole body fat oxidation levels. Both LDD-fed females and males showed an enlarged intestinal tract. Although most of the phenotypical differences disappeared in adulthood in both sexes, females exposed to LDD versus HDD in the early post-weaning period showed improved metabolic flexibility in adulthood. Cumulatively, these results suggest that the type of starch introduced after weaning could, at least in females, program later-life health.
Genome-Wide Association Studies of Estimated Fatty Acid Desaturase Activity in Serum and Adipose Tissue in Elderly Individuals: Associations with Insulin Sensitivity
Authors: Marklund Matti , Morris Andrew P. , Mahajan Anubha , Ingelsson Erik , Lindgren Cecilia M. , Lind Lars , Risérus Ulf
Published: November 2018

Fatty acid desaturases (FADS) catalyze the formation of unsaturated fatty acids and have been related to insulin sensitivity (IS). FADS activities differ between tissues and are influenced by genetic factors that may impact the link to IS. Genome-wide association studies of δ-5-desaturase (D5D), δ-6-desaturase (D6D) and stearoyl-CoA desaturase-1 (SCD) activities (estimated by product-to-precursor ratios of fatty acids analyzed by gas chromatography) in serum cholesterol esters (n = 1453) and adipose tissue (n = 783, all men) were performed in two Swedish population-based cohorts. Genome-wide significant associated loci were evaluated for associations with IS measured with a hyperinsulinemic euglycemic clamp (n = 554). Variants at the FADS1 were strongly associated with D5D in both cholesterol esters (p = 1.9 × 10−70) and adipose tissue (p = 1.1 × 10−27). Variants in three further loci were associated with D6D in cholesterol esters (FADS2, p = 3.0 × 10−67; PDXDCI, p = 4.8 × 10−8; and near MC4R, p = 3.7 × 10−8) but no associations with D6D in adipose tissue attained genome-wide significance. One locus was associated with SCD in adipose tissue (PKDL1, p = 2.2 × 10−19). Genetic variants near MC4R were associated with IS (p = 3.8 × 10−3). The FADS cluster was the main genetic determinant of estimated FADS activity. However, fatty acid (FA) ratios in adipose tissue and cholesterol esters represent FADS activities in separate tissues and are thus influenced by different genetic factors with potential varying effects on IS.
Milk Other Than Breast Milk and the Development of Asthma in Children 3 Years of Age. A Birth Cohort Study (2006–2011)
Authors: El-Heneidy Asmaa , Abdel-Rahman Manar E. , Mihala Gabor , Ross Lynda J. , Comans Tracy A.
Published: November 2018

Prevalence of asthma in Australian children is amongst the highest in the world. Although breastfeeding positively influences infant immunity, early introduction of Milk Other than Breast Milk (MOTBM) may also play an important role in the development of Asthma. The aim of this study was to investigate the association between the introduction of MOTBM in the first six months after birth and the development of reported persistent asthma in 3-year olds. A sample of 1121 children was extracted from the Environments for Healthy Living longitudinal birth cohort study. Introduction of MOTBM during the first six months after birth increased almost two-fold the risk of development of persistent asthma after adjusting for other covariates (Adjusted Relative Risk (ARR): 1.71, 95% CI: 1.03–2.83, p = 0.038). This study indicates that the introduction of MOTBM in the first six months of life is a risk factor for asthma incidence among 3-year old children. This result is important in explaining the benefits of breastfeeding as part of public health interventions to encourage mothers to increase breastfeeding initiation and duration, and avoid the introduction of MOTBM in the first six months after childbirth.
Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR Trial
Authors: Ziegenfuss Tim N. , Kedia Anurag W. , Sandrock Jennifer E. , Raub Betsy J. , Kerksick Chad M. , Lopez Hector L.
Published: November 2018

Withania somnifera (Ashwagandha) is an Ayurvedic herb categorized as having “rasayana” (rejuvenator), longevity, and revitalizing properties. Sensoril® is a standardized aqueous extract of the roots and leaves of Withania somnifera. Purpose: To examine the impact of Sensoril® supplementation on strength training adaptations. Methods: Recreationally active men (26.5 ± 6.4 years, 181 ± 6.8 cm, 86.9 ± 12.5 kg, 24.5 ± 6.6% fat) were randomized in a double-blind fashion to placebo (PLA, n = 19) or 500 mg/d Sensoril® (S500, n = 19). Body composition (DEXA), muscular strength, power, and endurance, 7.5 km cycling time trial, and clinical blood chemistries were measured at baseline and after 12 weeks of supplementation and training. Subjects were required to maintain their normal dietary habits and to follow a specific, progressive overload resistance-training program (4-day/week, upper body/lower body split). 2 × 2 mixed factorial ANOVA was used for analysis and statistical significance was set a priori at p ≤ 0.05. Results: Gains in 1-RM squat (S500: +19.1 ± 13.0 kg vs. PLA +10.0 ± 6.2 kg, p = 0.009) and bench press (S500: +12.8 ± 8.2 kg vs. PLA: +8.0 ± 6.0 kg, p = 0.048) were significantly greater in S500. Changes in DEXA-derived android/gynoid ratio (S500: +0.0 ± 0.14 vs. PLA: +0.09 ± 0.1, p = 0.03) also favored S500. No other between-group differences were found for body composition, visual analog scales for recovery and affect, or systemic hemodynamics, however, only the S500 group experienced statistically significant improvements in average squat power, peak bench press power, 7.5 km time trial performance, and perceived recovery scores. Clinical chemistry analysis indicated a slight polycythemia effect in PLA, with no other statistical or clinically relevant changes being noted. Conclusions: A 500 mg dose of an aqueous extract of Ashwagandha improves upper and lower-body strength, supports a favorable distribution of body mass, and was well tolerated clinically in recreationally active men over a 12-week resistance training and supplementation period.
Factors Affecting Intracellular Delivery and Release of Hydrophilic Versus Hydrophobic Cargo from Mesoporous Silica Nanoparticles on 2D and 3D Cell Cultures
Authors: Desai Diti , Åkerfelt Malin , Prabhakar Neeraj , Toriseva Mervi , Näreoja Tuomas , Zhang Jixi , Nees Matthias , Rosenholm Jessica M.
Published: November 2018

Intracellular drug delivery by mesoporous silica nanoparticles (MSNs) carrying hydrophilic and hydrophobic fluorophores as model drug cargo is demonstrated on 2D cellular and 3D tumor organoid level. Two different MSN designs, chosen on the basis of the characteristics of the loaded cargo, were used: MSNs with a surface-grown poly(ethylene imine), PEI, coating only for hydrophobic cargo and MSNs with lipid bilayers covalently coupled to the PEI layer as a diffusion barrier for hydrophilic cargo. First, the effect of hydrophobicity corresponding to loading degree (hydrophobic cargo) as well as surface charge (hydrophilic cargo) on intracellular drug release was studied on the cellular level. All incorporated agents were able to release to varying degrees from the endosomes into the cytoplasm in a loading degree (hydrophobic) or surface charge (hydrophilic) dependent manner as detected by live cell imaging. When administered to organotypic 3D tumor models, the hydrophilic versus hydrophobic cargo-carrying MSNs showed remarkable differences in labeling efficiency, which in this case also corresponds to drug delivery efficacy in 3D. The obtained results could thus indicate design aspects to be taken into account for the development of efficacious intracellular drug delivery systems, especially in the translation from standard 2D culture to more biologically relevant organotypic 3D cultures.
Synthesis and Characterization of a Biomimetic Formulation of Clofazimine Hydrochloride Microcrystals for Parenteral Administration
Authors: Murashov Mikhail D. , Diaz-Espinosa Jennifer , LaLone Vernon , Tan Joel W. Y. , Laza Raluca , Wang Xueding , Stringer Kathleen A. , Rosania Gus R.
Published: November 2018

Clofazimine (CFZ) is a broad spectrum antimycobacterial agent recommended by the World Health Organization as a first line treatment for leprosy and second line treatment for multidrug resistant tuberculosis. Oral administration of CFZ leads to a red skin pigmentation side effect. Since CFZ is a weakly basic, red phenazine dye, the skin pigmentation side effect results from lipophilic partitioning of the circulating, free base (neutral) form of CFZ into the skin. Here, we developed a stable and biocompatible formulation of CFZ-HCl microcrystals that mimics the predominant form of the drug that bioaccumulates in macrophages, following long term oral CFZ administration. In mice, intravenous injection of these biomimetic CFZ-HCl microcrystals led to visible drug accumulation in macrophages of the reticuloendothelial system with minimal skin accumulation or pigmentation. In fact, no skin pigmentation was observed when the total amount of CFZ-HCl administered was equivalent to the total oral dose leading to maximal skin pigmentation. Thus, parenteral (injected or inhaled) biomimetic formulations of CFZ-HCl could be instrumental to avoid the pigmentation side effect of oral CFZ therapy.
Chitosan-Polylactide/Hyaluronic Acid Complex Microspheres as Carriers for Controlled Release of Bioactive Transforming Growth Factor-β1
Authors: Min Qing , Liu Jiaoyan , Li Jing , Wan Ying , Wu Jiliang
Published: November 2018

Chitosan(CH)-polylactide(PLA) copolymers containing varied PLA percentages were synthesized using a group-protection method and one of them with solubility in water-based solvents was used to prepare CH-PLA/hyaluronic acid (HA) complex microspheres for the delivery of transforming growth factor-β1 (TGF-β1). An emulsification processing method was developed for producing TGF-β1-loaded CH-PLA/HA microspheres using sodium tripolyphosphate (TPP) as ionic crosslinker and the size of the microspheres was devised to the micron level in order to achieve high encapsulating efficiency. The encapsulating efficiency, swelling property and release administration of the microspheres could be synergistically regulated by PLA component, the applied TPP dose and the incorporated HA amount. In comparison to CH/HA microspheres, the CH-PLA/HA microspheres had greatly reduced TGF-β1 release rates and were able to administrate the TGF-β1 release at controlled rates over a significant longer period of time. The released TGF-β1 was detected to be bioactive when compared to the free TGF-β1. These results suggest that the presently developed CH-PLA/HA complex microspheres have promising potential in delivering TGF-β1 for cartilage repair applications where the applied TGF-β1 amount in the early stage needs to be low whilst the sustained TGF-β1 release at an appropriate dose in the later stage has to be maintained
Comparative Study on Excretive Characterization of Main Components in Herb Pair Notoginseng-Safflower and Single Herbs by LC–MS/MS
Authors: Lu Ying-Yuan , Song Jin-Yang , Li Yan , Meng Yu-Qing , Zhao Ming-Bo , Jiang Yong , Tu Peng-Fei , Guo Xiao-Yu
Published: November 2018

The herbal medicine combination of notoginseng-safflower has been commonly used clinically for the prevention and treatment of cardiovascular diseases. A reliable liquid chromatography-tandem mass spectrometry (LC–MS/MS) method was developed for simultaneous determination of six bioactive components (hydroxysafflor yellow A, notoginsenoide R1, ginsenoside Rb1, Re, Rd, and Rg1) in rat urine and feces after oral administration of notoginseng total saponins (NS), safflower total flavonoids (SF), and the combination of NS and SF (CNS). The chromatographic separation was achieved on a Waters HSS T3 column under gradient elution with acetonitrile and water containing formic acid as the mobile phase. The calibration curves were linear, with correlation coefficient (r) > 0.99 for six components. The intra- and interday precision (RSD) and accuracy (RE) of QC samples were within −14.9% and 14.9%, respectively. The method was successfully applied to study of the urinary and fecal excretion of six bioactive constituents following oral administration of NS, SF, and CNS in rats. Compared to the single herb, the cumulative excretion ratios of six constituents were decreased in the herbal combination. The study indicated that the combination of notoginseng and safflower could reduce the renal and fecal excretion of the major bioactive constituents and promote their absorption in rats.
Diatoms Green Nanotechnology for Biosilica-Based Drug Delivery Systems
Authors: Terracciano Monica , De Stefano Luca , Rea Ilaria
Published: November 2018

Diatom microalgae are the most outstanding natural source of porous silica. The diatom cell is enclosed in a three-dimensional (3-D) ordered nanopatterned silica cell wall, called frustule. The unique properties of the diatom frustule, including high specific surface area, thermal stability, biocompatibility, and tailorable surface chemistry, make diatoms really promising for biomedical applications. Moreover, they are easy to cultivate in an artificial environment and there is a large availability of diatom frustules as fossil material (diatomite) in several areas of the world. For all these reasons, diatoms are an intriguing alternative to synthetic materials for the development of low-cost drug delivery systems. This review article focuses on the possible use of diatom-derived silica as drug carrier systems. The functionalization strategies of diatom micro/nanoparticles for improving their biophysical properties, such as cellular internalization and drug loading/release kinetics, are described. In addition, the realization of hybrid diatom-based devices with advanced properties for theranostics and targeted or augmented drug delivery applications is also discussed.
Development of Paroxetine Hydrochloride Single Layer Controlled-Release Tablets Based on 32 Factorial Design
Authors: Yang Yao , Huang Zhengwei , Zhang Xuan , Li Jinyuan , Huang Ying , Chen Wanxin , Pan Xin , Wu Chuanbin
Published: November 2018

Major depressive disorder (MDD) is one of the main contributors to disability and suicide mortality globally. Paroxetine hydrochloride (PHH) is the most potent antidepressant used for MDD treatment. Due to its reduced side effects PAXIL® CR is a widely-used controlled-release formulation of PHH. However, the complicated double-layer production of PAXIL® CR faces the risk of layer separation. In this study, PHH enteric coating single layer controlled-release tablets (PHH-EC-SLTs) were designed as a simplified substitution of PAXIL® CR through a rational formulation screening. The optimized PHH-EC-SLTs showed similar release behaviors in vitro to PAXIL® CR and the release profiles corresponded to a zero-order release model (R2 = 0.9958). Polymer matrix erosion was the main release mechanism, according to the fitting exponents n > 1 in the Korsmeyer-Pappas model. Crucial pharmacokinetic parameters including peak-reaching time (Tmax), peak concentration (Cmax) and the area under the blood level-time curve (AUC0-48) of PHH-EC-SLTs and PAXIL® CR had no significant difference (p > 0.05) and the relative bioavailability (F = 97.97%) of PHH-EC-SLTs demonstrated their similar pharmacokinetic profiles in vivo. In view of avoiding layer separation risk and simplifying the preparation processing, the self-made PHH-EC-SLTs could be considered as a safe and economic alternative to PAXIL® CR.
N-(2-Hydroxy)-propyl-3-trimethylammonium, O-Mysristoyl Chitosan Enhances the Solubility and Intestinal Permeability of Anticancer Curcumin
Authors: Silva Daniella S. , M. dos Santos Danilo , Almeida Andreia , Marchiori Leonardo , Campana-Filho Sérgio P. , Ribeiro Sidney J. L. , Sarmento Bruno
Published: November 2018

An amphiphilic derivative of chitosan containing quaternary ammonium and myristoyl groups, herein named as ammonium myristoyl chitosan (DMCat), was synthesized by reacting glycidyltrimethylammonium chloride (GTMAC) and myristoyl chitosan (DMCh). The success of the modification was confirmed using Fourier-transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance (NMR) spectroscopy. The average degrees of alkylation and quaternization ( D Q ¯ ) were determined by using 1H NMR and conductometric titration. The zeta potential of the micelles was higher than 28 mV while its average size and encapsulation efficiency ranged from 280 nm to 375 nm and 68% to 100%, respectively. The in vitro cytotoxicity of the unloaded and curcumin (CUR)-loaded micelles was tested against Caco-2 and HT29-MTX intestinal epithelial cell lines. The results showed no cytotoxic effect from loaded and unloaded micelles as compared to free CUR. In the permeability test, it was observed that both types of micelles, i.e., DMCh and DMCat, improved CUR permeability. Additionally, higher permeability was verified for both systems in Caco-2/HT29-MTX:Raji B because of the mucoadhesive character of chitosan and its ability to open tight junctions. The results indicated that DMCat micelles, due to the physico-chemical, improved characteristics may be a promising carrier to encapsulate CUR aiming cancer therapy.
Development of a Dynamic Model and Control System for Load-Following Studies of Supercritical Pulverized Coal Power Plants
Authors: Sarda Parikshit , Hedrick Elijah , Reynolds Katherine , Bhattacharyya Debangsu , Zitney Stephen E. , Omell Benjamin
Published: November 2018

Traditional energy production plants are increasingly forced to cycle their load and operate under low-load conditions in response to growth in intermittent renewable generation. A plant-wide dynamic model of a supercritical pulverized coal (SCPC) power plant has been developed in the Aspen Plus Dynamics® (APD) software environment and the impact of advanced control strategies on the transient responses of the key variables to load-following operation and disturbances can be studied. Models of various key unit operations, such as the steam turbine, are developed in Aspen Custom Modeler® (ACM) and integrated in the APD environment. A coordinated control system (CCS) is developed above the regulatory control layer. Three control configurations are evaluated for the control of the main steam; the reheat steam temperature is also controlled. For studying servo control performance of the CCS, the load is decreased from 100% to 40% at a ramp rate of 3% load per min. The impact of a disturbance due to a change in the coal feed composition is also studied. The CCS is found to yield satisfactory performance for both servo control and disturbance rejection.
Production Process Optimization of Metal Mines Considering Economic Benefit and Resource Efficiency Using an NSGA-II Model
Authors: Wang Xunhong , Gu Xiaowei , Liu Zaobao , Wang Qing , Xu Xiaochuan , Zheng Minggui
Published: November 2018

The optimization of the production process of metal mines has been traditionally driven only by economic benefits while ignoring resource efficiency. However, it has become increasingly aware of the importance of resource efficiency since mineral resource reserves continue to decrease while the demand continues to grow. To better utilize the mineral resources for sustainable development, this paper proposes a multi-objective optimization model of the production process of metal mines considering both economic benefits and resource efficiency. Specifically, the goals of the proposed model are to maximize the profit and resource utilization rate. Then, the fast and elitist Non-Dominated Sorting Genetic Algorithm (NSGA-II) is used to optimize the multi-objective optimization model. The proposed model has been applied to the optimization of the production process of a stage in the Huogeqi Copper Mine. The optimization results provide a set of Pareto-optimal solutions that can meet varying needs of decision makers. Moreover, compared with those of the current production indicators, the profit and resource utilization rate of some points in the optimization results can increase respectively by 2.99% and 2.64%. Additionally, the effects of the decision variables (geological cut-off grade, minimum industrial grade and loss ratio) on objective functions (profit and resource utilization rate) were discussed using variance analysis. The sensitivities of the Pareto-optimal solutions to the unit copper concentrate price were studied. The results show that the Pareto-optimal solutions at higher profits (with lower resource utilization rates) are more sensitive to the unit copper concentrate prices than those obtained in regions with lower profits.