bluuebunny/crossref_metadata_2025 huggingface dataset:
PEAT-CONTAINING COMPOSITION CONTAINING MAGNESIA BINDER
Authors: Mitina Natalia A. , Lotov Vasiliy A. , Kovaleva Margarita A. , Kopanitsa Natali O.
Published: August 2018

Based on the new hydraulic magnesia binder, the compositions of the peat-containing composite material have been proposed and investigated. Hydraulic magnesia binder is an astringent composition of hydration-reaction hardening, which consists of an active caustic magnesia powder and a mixing fluid. As the fluid mixing an aqueous solution of magnesium bicarbonate Mg(HCO3)2 with a concentration of 13 g/l was used. Hardening forms water-insoluble products - magnesium hydroxide Mg(OH)2 and magnesium bicarbonates of general formula MgCO3·zMg(OH)2·nH2O, which makes it possible to harden and used products based on such a binder as in the air, and in water. The use of peat as a filler of the developed compositions will make it possible to obtain lightweight waterproof materials and products of heat-insulating purpose. It has been shown that the peat-and-magnesian compositions of all compositions have a hydration hardening coefficient of more than 1.0, which indicates intensification of the hydration and hardening processes in water conditions in comparison with air and large strength parameters. Using XRD the phase composition of peat products and peat- magnesium hardening compositions was established. Thermal analysis showed the presence of magnesium hydrogencarbonates in samples of compositions that are in the form of slightly crystallized neoplasms. Investigations by electron microscopy confirmed the presence of hydrocarbons such as magnesium particles dipingite Mg5(CO3)4(OH)2·5H2O and hydromagnesite Mg5(CO3)4(OH)2·4H2O in the form of thin plates with the vertical direction of crystallization. Increased water resistance of compositions based on hydraulic magnesia binder with non-water-resistant filler peat is due to mineralization of peat particles due to their impregnation with a solution of magnesium bicarbonate and the formation of water-soluble magnesium hydrogen carbonates in the loose porous structure of peat.
HEAT OF HYDRATION OF DIETHYLSULFONE BY QUANTUM CHEMICAL CALCULATION
Authors: Mkhitaryan Ashot S. , Papanyan Zakar K. , Gabrielyan Liana S. , Markarian Shiraz A.
Published: August 2018

The quantum chemical study of the hydration of diethyl sulfone was performed by using Gaussian 09 software package. The conformational analysis of the isolated molecule of diethyl sulfone is performed by the restricted Hartree-Fock (RHF) and the density functional theory (DFT/B3PW91) methods with 6-311++G(d,p) extended basis set. The analysis of the potential energy surface revealed the existence of four stable conformers of diethyl sulfone with different degrees of degeneracy. The nature of stationary points on the potential energy surface is verified by the complete gas phase optimization and the vibrational analysis. The global minimum is the conformer with two (CCSC) dihedral angles equal 180°. The fractional population distribution of different conformers is determined by Boltzmann distribution. The average energy of the diethyl sulfone molecule in vacuum is calculated. To account the effect of solvent the self-consistent reaction field (SCRF) method, particularly, solvent model based on electron density (SMD), was employed. It is shown, that solvent affects on the relative population of conformers. The thermodynamic parameters, in particular enthalpy, for the conformers of diethyl sulfone are determined both in the gas phase and in the aqueous solution. The average energy of diethyl sulfone in water is calculated. It is shown, that although the dissolution of crystalline diethyl sulfone in water is an endothermic process, the hydration of diethyl sulfone molecules occurs with the release of heat. The heat of dissolution of diethyl sulfone calculated by the density functional theory is consistent with the experimental data.
DETERMINATION OF CHLORHEXIDINE DIGLUCONATE IN DISINFECTANTS
Authors: Andreev Sergey V. , Belyaev Evgeny S. , Ivanova Anna O. , Novikova Elvina A. , Ishchenko Anatoly A.
Published: August 2018

Chlorhexidine digluconate has been widely used in lenticular compositions, skin antiseptics and other ready-to-use disinfectants. This is due to its low toxicity, as well as a wide range of antimicrobial effects. A commonly used method for the analysis of commercially available chlorhexidine digluconate (usually available as a 20% aqueous solution) is high-performance liquid chromatography. In this article, the main methods of analysis used to determine chlorhexidine digluconate in disinfectants and skin antiseptics are considered. A new simple technique for the determination of chlorhexidine digluconate in technical products and disinfectants based on acid-base titration in alcohol-ketone is developed. It is shown that in this medium hydrochloric acid interacts with two nitrogen atoms of the chlorhexidine digluconate molecule. The end point of the titration is established by the transition of the blue color to green in the presence of bromophenol blue. The range of measured concentrations is from 0.1 to 2.0 mass%. The relative error of the method is 2.5% with the confidence probability P = 0.95. A comparison of the diode array detector and the charged aerosol detector for the determination of chlorhexidine digluconate has been performed. It is shown that a charged aerosol detector can be used to analyze chlorhexidine digluconate in cases where it is difficult to analyze with an ultraviolet or diode array detector. However, the sensitivity of the detector of charged aerosols is significantly lower than that of the diode matrix, and the linearity range is smaller. All methods were tested on model samples, as well as on samples of disinfectants, skin antiseptics, soaps and wipes with antibacterial effect.
PHYSICAL AND CHEMICAL AND BIOLOGICAL MONITORING IN CENTRAL RUSSIA: INVESTIGATION OF QUALITY OF ATMOSPHERIC AIR AND SOIL IN TERRITORY OF RODNIKI CITY
Authors: Dunaev Anatoly M. , Rumyantsev Igor V. , Agapova Irina B. , Grinevich Vladimir I. , Vergel Konstantin N. , Gundorina Svetlana F.
Published: August 2018

Air and soil quality assessment at the Rodniki town, Ivanovo Region, was performed using physical chemical analysis and biomonitoring techniques: soil and snow analysis, moss biomonitoring, fluctuating asymmetry (IFA) for the silver birch (Betula pendula Roth.). Elemental content in moss, soil and snow samples was determined by neutron activation analysis (NAA) and atomic absorption spectrometry (AAS). A total of 40 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, In, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, Ta, W) was determined by NAA. To determine concentrations of Pb, Cd, and Cu AAS technique was used. To reveal potential sources of element-pollutants the descriptive statistics and factor analysis were applied in OriginPro 8 and SPSS 17.0 software packages for Windows. To evaluate the contribution to the metal content in moss from anthropogenic sources, enrichment factors (EF) were calculated. Distribution maps were prepared to point out areas most affected by pollution and to characterize the main deposition patterns of pollutants. To create GIS maps QGIS software was used. The complex assessment of the air and soil quality of the Rodniki town and its vicinity showed an acceptable level of the contamination. It was established that the main source of pollution is the machine-building plant situated in the north of the town. This plant causes soil contamination by Zn, As, Fe, and Co. The IFA values successfully confirm the obtained concentration data. Besides, it was established that the soil contamination has a bigger influence on IFA than atmospheric pollution. Measures for nature conservation are suggested.
Representations of the East: Orientalism in Emily Eden’s Travel Writing
Authors: Svendsen Amalie Due
Published: August 2018

The publication of Orientalism by Edward W. Said in 1978 gave rise to a new area of studies examining how representations of the East were influenced by an Orientalist discourse, which functioned to maintain and justify Western hegemony. Emily Eden’s letters from her travels in Colonial India are examples of such representations, as they depict her meeting with and perception of the colonial Other. I argue that Eden’s writing displays Orientalism, as she tends to dissociate herself from the Indians through othering, in order to preserve her national identity. However, Eden’s letters are distinguished from other Orientalist travel writing in the sense that she does not articulate justification of Western superiority. Thus, I argue, that the Orientalist discourse demonstrated in Eden’s letters serves the personal purpose of self-definition rather than the political purpose of justifying colonial rule.
Aligned Drawings of Planar Graphs
Authors: Mchedlidze Tamara , Radermacher Marcel , Rutter Ignaz
Published: August 2018

Let $G$ be a graph that is topologically embedded in the plane and let $\mathcal A$ be
an arrangement of pseudolines intersecting the drawing of $G$. An
aligned drawing of $G$ and $\mathcal A$ is a planar polyline drawing
$\Gamma$ of $G$ with an arrangement $A$ of lines so that $\Gamma$ and
$A$ are homeomorphic to $G$ and $\mathcal A$. We show that if $\mathcal A$ is
stretchable and every edge $e$ either entirely lies on a pseudoline or it has
at most one intersection with $\mathcal A$, then $G$ and $\mathcal A$ have a
straight-line aligned drawing. In order to prove this result, we
strengthen a result of Da Lozzo et al. [Da Lozzo et al. GD 2016], and prove that
a planar graph $G$ and a single pseudoline $\mathcal L$ have an aligned drawing
with a prescribed convex drawing of the outer face. We also study the less
restrictive version of the alignment problem with respect to one line,
where only a set of vertices is given and we
need to determine whether they can be collinear. We show that the problem
is $\mathcal{NP}$-complete but fixed-parameter tractable.
A Faster Algorithm for Maximum Induced Matchings on Circle Graphs
Authors: Ward Max , Gozzard Andrew , Wise Michael , Datta Amitava
Published: August 2018

Circle graphs have applications to RNA bioinformatics, computational chemistry, and VLSI design. Additionally, many problems that are intractable on general graphs are efficient for circle graphs. This has driven research into algorithms for circle graphs. One well known graph problem is to find a maximum induced matching. This is NP-Hard, even for bipartite graphs. No algorithm for this problem that works directly on circle graphs has been proposed. However, since circle graphs are included in interval filament graphs, algorithms for this class can be applied to circle graphs. Unfortunately, this entails a large computational cost of $O(|V|^6)$ time. We propose an algorithm that operates directly on circle graphs, and requires only $O(|V|^3)$ time.
Stage-dependent remodeling of projections to motor cortex in ALS mouse model revealed by a new variant retrograde-AAV9
Authors: Commisso Barbara , Ding Lingjun , Varadi Karl , Gorges Martin , Bayer David , Boeckers Tobias M , Ludolph Albert C , Kassubek Jan , Müller Oliver J , Roselli Francesco
Published: August 2018

Amyotrophic lateral sclerosis (ALS) is characterized by the progressive degeneration of motoneurons in the primary motor cortex (pMO) and in spinal cord. However, the pathogenic process involves multiple subnetworks in the brain and functional MRI studies demonstrate an increase in functional connectivity in areas connected to pMO despite the ongoing neurodegeneration. The extent and the structural basis of the motor subnetwork remodeling in experimentally tractable models remain unclear. We have developed a new retrograde AAV9 to quantitatively map the projections to pMO in the SOD1(G93A) ALS mouse model. We show an increase in the number of neurons projecting from somatosensory cortex to pMO at presymptomatic stages, followed by an increase in projections from thalamus, auditory cortex and contralateral MO (inputs from 20 other structures remains unchanged) as disease advances. The stage- and structure-dependent remodeling of projection to pMO in ALS may provide insights into the hyperconnectivity observed in ALS patients.
How the cerebellum learns to build a sequence
Authors: Shadmehr Reza
Published: August 2018

Rabbits can learn the biological analogue of a simple recursive function by relying only on the neurons of the cerebellum.
Genetic diversity and antimicrobial resistance ofSalmonellaserotypes recovered throughout the beef production chain and from patients with salmonellosis
Authors: Realpe-Quintero Mauricio , Barba-León Jeannette , Pérez-Montaño Julia A. , Pacheco-Gallardo Carlos , González-Aguilar Delia , Dominguez-Arias Rosa M. , Cabrera-Diaz Elisa
Published: August 2018

Salmonellais one of the major foodborne pathogens worldwide. The antimicrobial resistance (AMR) of this foodborne pathogen has raised a great concern in recent years. Studies on the frequency and characterization ofSalmonellaserotypes can help to improve our knowledge on the epidemiology of this pathogen. The purpose of this study was to compare the serotypes, AMR and genetic profiles ofSalmonellaisolates recovered from raw beef throughout the beef production chain and from human feces associated with clinical cases of salmonellosis. The serotype, AMR and pulsed-field gel electrophoresis profile of 243Salmonella entericaisolates recovered from beef carcasses (n = 78), ground beef (n = 135), and human feces from clinical cases of salmonellosis (n = 30) were compared. Forty-three differentSalmonellaserotypes were identified and regardless of the source, the top five corresponded to Typhimurium, Give, Group B (partially serotyped), Infantis and Anatum. Twelve serotypes from beef carcasses were also found in ground beef, showing their presence throughout the beef production chain.SalmonellaTyphimurium, Infantis, Anatum and Montevideo were the only serotypes identified in all sample types. Resistance to tetracyclines was the most frequent (41.2%) followed by resistance to aminoglycosides (37%), folate pathway inhibitors (21%), quinolones (20.2%), phenicols (17.1%), penicillins (15.6%) and cephems (7%). Multidrug resistance was observed in 28.8% of the isolates, and those from human feces showed resistance to a larger number of antimicrobials. Great concern arises from the resistance and reduced susceptibility observed to quinolones and cephalosporins because these drugs are the first line of treatment for invasiveSalmonellainfections. Twenty-seven distinct pulse-types were detected among 238 isolates. Clustering analysis for the most frequent serotypes identified groups of isolates with similar AMR profiles. Multidrug resistance spreading throughout the food production chain should be continually monitored and its importance emphasized.
The effect of walking speed on the foot inter-segment kinematics, ground reaction forces and lower limb joint moments
Authors: Sun Dong , Fekete Gusztáv , Mei Qichang , Gu Yaodong
Published: August 2018

Background

Normative foot kinematic and kinetic data with different walking speeds will benefit rehabilitation programs and improving gait performance. The purpose of this study was to analyze foot kinematics and kinetics differences between slow walking (SW), normal walking (NW) and fast walking (FW) of healthy subjects.

Methods

A total of 10 healthy male subjects participated in this study; they were asked to carry out walks at a self-selected speed. After measuring and averaging the results of NW, the subjects were asked to perform a 25% slower and 25% faster walk, respectively. Temporal-spatial parameters, kinematics of the tibia (TB), hindfoot (HF), forefoot (FF) and hallux (HX), and ground reaction forces (GRFs) were recorded while the subjects walked at averaged speeds of 1.01 m/s (SW), 1.34 m/s (NW), and 1.68 m/s (FW).

Results

Hindfoot relative to tibia (HF/TB) and forefoot relative to hindfoot (FF/HF) dorsiflexion (DF) increased in FW, while hallux relative to forefoot (HX/FF) DF decreased. Increased peak eversion (EV) and peak external rotation (ER) in HF/TB were observed in FW with decreased peak supination (SP) in FF/HF. GRFs were increased significantly with walking speed. The peak values of the knee and ankle moments in the sagittal and frontal planes significantly increased during FW compared with SW and NW.

Discussion

Limited HF/TB and FF/HF motion of SW was likely compensated for increased HX/FF DF. Although small angle variation in HF/TB EV and FF/HF SP during FW may have profound effects for foot kinetics. Higher HF/TB ER contributed to the FF push-off the ground while the center of mass (COM) progresses forward in FW, therefore accompanied by higher FF/HF abduction in FW. Increased peak vertical GRF in FW may affected by decreased stance duration time, the biomechanical mechanism maybe the change in vertical COM height and increase leg stiffness. Walking speed changes accompanied with modulated sagittal plane ankle moments to alter the braking GRF during loading response. The findings of foot kinematics, GRFs, and lower limb joint moments among healthy males may set a reference to distinguish abnormal and pathological gait patterns.
Observer‐based robust adaptive force‐position controller design for quadruped robots with actuator faults
Authors: Farid Yousef , Majd Vahid Johari , Ehsani‐Seresht Abbas
Published: August 2018

This paper deals with the robust adaptive tracking control problem for an uncertain quadruped robot subject to the time‐varying actuator faults. First, the desired interaction forces of the robot legs with the ground are calculated using a pseudo‐inverse method. The proposed scheme includes a sliding‐mode angular velocity observer, an adaptive fault estimator, and an adaptive sliding‐mode force‐position controller. The amplitude of the actuator faults and the upper bounds of the lumped uncertainties are adaptively estimated, and appropriate modifications are provided to the joint torque control signal. The tracking errors of the overall closed‐loop system, as well as the fault estimation error, are guaranteed to converge to the neighborhood of the origin using the Lyapunov stability theorem. Finally, numerical simulations are exhibited to demonstrate the performance of the developed method.
Digitally Tunable Microfluidic Bioprinting of Multilayered Cannular Tissues
Authors: Pi Qingmeng , Maharjan Sushila , Yan Xiang , Liu Xiao , Singh Bijay , van Genderen Anne Metje , Robledo‐Padilla Felipe , Parra‐Saldivar Roberto , Hu Ning , Jia Weitao , Xu Changliang , Kang Jian , Hassan Shabir , Cheng Haibo , Hou Xu , Khademhosseini Ali , Zhang Yu Shrike
Published: August 2018

Despite advances in the bioprinting technology, biofabrication of circumferentially multilayered tubular tissues or organs with cellular heterogeneity, such as blood vessels, trachea, intestine, colon, ureter, and urethra, remains a challenge. Herein, a promising multichannel coaxial extrusion system (MCCES) for microfluidic bioprinting of circumferentially multilayered tubular tissues in a single step, using customized bioinks constituting gelatin methacryloyl, alginate, and eight‐arm poly(ethylene glycol) acrylate with a tripentaerythritol core, is presented. These perfusable cannular constructs can be continuously tuned up from monolayer to triple layers at regular intervals across the length of a bioprinted tube. Using customized bioink and MCCES, bioprinting of several tubular tissue constructs using relevant cell types with adequate biofunctionality including cell viability, proliferation, and differentiation is demonstrated. Specifically, cannular urothelial tissue constructs are bioprinted, using human urothelial cells and human bladder smooth muscle cells, as well as vascular tissue constructs, using human umbilical vein endothelial cells and human smooth muscle cells. These bioprinted cannular tissues can be actively perfused with fluids and nutrients to promote growth and proliferation of the embedded cell types. The fabrication of such tunable and perfusable circumferentially multilayered tissues represents a fundamental step toward creating human cannular tissues.
Recent Advances and Perspectives in the Synthesis of HeterocyclesviaZinc Catalysis
Authors: Keerthi Krishnan K. , Ujwaldev Sankuviruthiyil M. , Saranya Salim , Anilkumar Gopinathan , Beller Matthias
Published: August 2018

Among the various metal catalysts, zinc salts have enormous potential due to their availability, low toxicity, eco‐friendliness and inexpensive nature. Biologically zinc is an essential element in our daily lives and it possesses a wide range of applications in pharmaceutical as well as material sciences. In synthetic organic chemistry, the main role of zinc salts is as a Lewis acid catalyst. The importance of the synthesis of heterocycles is attested by the vast number of applications of these compounds in the chemical and pharmaceutical industries. The environmentally benign nature of zinc, its abundance and the Lewis acid character of most of its compounds make it a suitable catalyst for heterocycle synthesis. This is the first review exclusively on zinc‐catalyzed heterocycle synthesis and deals with the recent applications, especially using tandem/domino or one‐pot reaction strategies and covers the literature from 2008 to 2018.

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Transition Metal‐free gem‐difluorocyclopropanation of Alkenes with CF3SiMe3−NaI System: a Recipe for Electron‐deficient Substrates
Authors: Nosik Pavel S. , Ryabukhin Sergey V. , Grygorenko Oleksandr O. , Volochnyuk Dmitriy M.
Published: August 2018

Reaction of various electron‐deficient alkenes, as well as functionalized styrene derivatives with CF3SiMe3−NaI system is studied. Relative reactivity of the substrates is established. It is shown that many α,β‐unsaturated esters can be difluorocyclopropanated efficiently under “slow addition protocol” conditions, which provides access to mono‐ and spirocyclic gem‐difluorocyclopropyl‐substituted carboxylic acids with good yields (36–79% for two steps) on up to 100 g scale.

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Addition of Mineral‐Coated Microparticles to Soluble Interleukin‐1 Receptor Antagonist Injected Subcutaneously Improves and Extends Systemic Interleukin‐1 Inhibition
Authors: Clements Anna E. B. , Leiferman Ellen M. , Chamberlain Connie S. , Vanderby Ray , Murphy William L.
Published: August 2018

IL‐1 receptor antagonist (IL‐1Ra) inhibits the pro‐inflammatory activity of IL‐1β. However, its short in vivo half‐life and high dose required to inhibit IL‐1β may limit its use in all but a few clinical scenarios. This study examines whether the addition of mineral‐coated microparticles (MPs) to a solution of IL‐1Ra extends its ability to inhibit IL‐1β activity when administered as a subcutaneous injection. MPs efficiently bind proteins in solution and provide sustained protein delivery. In vitro assays demonstrate that IL‐1Ra released from MPs is biologically active and inhibits IL‐1β activity. When MPs are added to an IL‐1Ra solution and injected subcutaneously into a murine model, serum IL‐1Ra is elevated for a longer duration compared to the treatment with the IL‐1Ra solution alone. Further, the addition of MPs to the IL‐1Ra solution results in the inhibition of IL‐1β activity for 7 days. A novel MP formulation that layered IL‐1Ra throughout the coating extends inhibition of IL‐1β activity in vivo for at least 14 days, suggesting potential for long‐term IL‐1β inhibition. Overall addition of MPs to an IL‐1Ra solution injected subcutaneously prolongs the duration of elevated serum concentration of IL‐1Ra and extends its ability to inhibit IL‐1β activity.
Empowerment and Accountability and Multi‐layered Contexts of Influences: Parenting and the Avoidance of Harm in Harare, Zimbabwe
Authors: Wini Dari Noreen Kudzanai , Mawodza Obdiah , Mingo Ericka , Olson Bradley D.
Published: August 2018

In this paper, the authors discuss multi‐level systems for parenting in Harare, Zimbabwe. At the micro‐system level, the Tirere Pamwe parenting program is a supportive, empowering prototype, designed to educate parents on child development, with a special focus on socio‐emotional development, from birth to age 18 years. The program has been delivered to a diverse group of parents, in diverse settings, which has helped to bring a greater contextual relevance to parenting practices, and seems thereby to have increased the mental well‐being of children. At the macro‐system level, international law and Zimbabwaean laws emphasise the need to protect children from both physical and psychological harm. These different layers are examined through the varying theoretical perspectives of community psychologist Julian Rappaport (, , , , ), such as his emphasis on paradox, empowerment, second‐order change, and narrative.
High‐strength, tough, rapidly self‐recoverable, and fatigue‐resistant hydrogels based on multi‐network and multi‐bond toughening mechanism
Authors: Zhuang Zhenzhen , Wu Linlin , Ma Xiaofeng , Diao Wenjing , Fang Ying
Published: August 2018

Constructing double network (DN) or triple network (TN) with two or three asymmetric independent polymer networks are very useful structural platforms to integrate different mechanisms for dissipating energy and maintaining elasticity for designing tough hydrogels. To reveal the roles of different cross‐linked networks with hierarchical bond energy across multiple length scales in the gel network, here we fabricate chemical–physical hybrid cross‐linked polyacrylamide/Agar/poly(vinyl alcohol) (PAM/Agar/PVA) TN hydrogels through multi‐network and multi‐bond toughening mechanism design, and compare these TN gels with single network and DN gels. Under deformation, the covalently cross‐linked PAM first network remain intact to maintain their original configuration, while the dynamic and reversible nanoscale hydrogen bonds in Agar second network and microcrystalline domain in PVA third network successively break to gradually dissipate energy and then recombine to recover the network, which lead to excellent mechanical strength (compression strength 2.6 MPa, tensile strength 197 kPa), toughness (energy dissipation up to 374 kJ/m3 at 200% strain), excellent recoverability (~87% toughness recovery after 15 min resting at room temperature), and self‐healing properties. The combination of high‐strength, self‐recovery, and self‐healing properties makes PAM/Agar/PVA TN gels promising candidates for further functional application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46847.
Amino‐functionalized magnetic zirconium alginate beads for phosphate removal and recovery from aqueous solutions
Authors: Luo Huayong , Rong Hongwei , Zhang Tian C. , Zeng Xueyang , Wan Jun
Published: August 2018

Amino‐functionalized magnetic zirconium alginate beads with an interpenetrating network (Fe3O4/PAM/SA–Zr) were prepared, characterized, and then tested as a novel biomass adsorbent for phosphate removal and recovery. The hydrogel beads exhibited outstanding thermostability and possessed a magnetic response. The effects of the pH, dosage, initial phosphate concentration, interference ions, and temperature on the removal of phosphate were investigated. The kinetics, isotherms, and thermodynamics of the adsorption were studied. Notably, the adsorption of phosphate was endothermic, feasible, and spontaneous with a maximum uptake capacity of 42.23 mg‐P/g at an optimized pH of 2.0. The phosphate could be desorbed effectively with a 0.2 mol/L NaOH solution, and the adsorbent exhibited a good reusability. The possible adsorption mechanisms were verified by zeta potential, Fourier transform infrared spectroscopy, and X‐ray photoelectron spectroscopy analyses. Continuous phosphate‐adsorption tests were conducted in a fixed‐bed columns packed with Fe3O4/PAM/SA–Zr, and the breakthrough curves were predicted by the Adams–Bohart, Thomas, and Yoon–Nelson models, respectively. The suitability of the hydrogel beads for the treatment of real wastewater was also tested. These hydrogel beads should be a promising adsorbent for phosphate removal and recovery from aqueous solutions, with the advantages of a high uptake capacity, good reusability, and easy magnetic separation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46897.
Research on the electrospun foaming process to fabricate three‐dimensional tissue engineering scaffolds
Authors: Zhao Peng , Cao Mingyi , Gu Haibing , Gao Qing , Xia Neng , He Yong , Fu Jianzhong
Published: August 2018

Three‐dimensional (3D) tissue engineering scaffolds were fabricated by an electrospun foaming process. A two‐dimensional (2D) membrane was fabricated first by the electrospinning technology, and then a sodium borohydride gas foaming process was used to expand the 2D membrane to a 3D tissue engineering scaffold. The effects of six process parameters on the foamed height of 3D scaffolds were systematically studied during fabrication using a L27(313) orthogonal design table. The mechanism of the gas foaming process was investigated by a porosity analysis and a scanning electron microscopy analysis of the scaffolds' surface and cross‐sectional morphology. Finally, wettability experiments and L929 fibroblast adhesion and proliferation experiments were carried out on the 3D scaffolds. The results showed that the concentration of polycaprolactone (PCL) has the most significant effect on height, and the optimal process parameters were 8 wt % PCL solution, 15 kV voltage, 4 mL h−1 flow rate, 20 cm distance, 60 min spinning time, and 5 g sodium borohydride. The 2D membrane with a smaller fiber diameter and higher porosity was more easily foamed. The fabricated 3D scaffold had good wettability, and cell absorbance (OD value) increased by 25.34% on day 7 over that of the 2D electrospun nanofibrous scaffold. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46898.
pH‐sensitive hydrogel based on carboxymethyl chitosan/sodium alginate and its application for drug delivery
Authors: Xie Cong‐Xia , Tian Ting‐Cui , Yu Shi‐Tao , Li Lu
Published: August 2018

Carboxymethyl chitosan sodium salt (CMCS)/sodium alginate (SA), a pH‐sensitive hydrogel composed of CMCS and SA crosslinked by 1‐ethyl‐3‐(3‐dimethyl aminopropyl) carbodiimide (EDC) and N‐hydroxysuccinimide, has been evaluated in vitro as a potential carrier for protein drug delivery of bovine serum albumin (BSA). The crosslinked structures, pore morphologies, and mechanical properties of the composite CMCS/SA hydrogel at different pH have been characterized by Fourier‐transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and dynamic mechanical analysis (DMA). The swelling behavior of the prepared hydrogel was assessed at different pH values, 1.2, 4.0, 6.86, 7.4, and 9.0. The in vitro slow release ability of the CMCS/SA hydrogel was assessed at 37°C and pH 1.2 or pH 7.4 to simulate gastrointestinal and mouth environments in vivo. The efficiency was found to be greater than 90% at pH 7.4. The composite CMCS/SA hydrogel showed no cytotoxic effect toward L‐929 cells according to the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide test. These findings demonstrate that the composite hydrogel has promising potential for drug delivery. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46911.
Performance of silk‐polypyrrole bilayer actuators under biologically relevant conditions
Authors: Hagler J. R. , Peterson B. N. , Murphy A. R. , Leger J. M.
Published: August 2018

Biocompatible actuators that are capable of controlled movement and can function under biologically relevant conditions are of significant interest for biomedical applications. Previously, we have demonstrated that a composite material of silk biopolymer and the conducting polymer poly(pyrrole) (PPy) can be formed into a functional bilayer bending actuator. Further, these silk‐PPy composites can generate forces comparable to human muscle (>0.1 MPa) making them ideal candidates for interfacing with biological tissues. Here, we explore the performance of these silk‐PPy composite bilayer actuators under biologically relevant conditions including exposure to proteins, serum, enzymes, and biologically relevant temperatures. Free‐end bending actuation performance, current response, force generation, and mass degradation under these conditions were investigated. We find that under the conditions tested here, the performance of our silk‐PPy composites is sensitive to both protein serum and enzyme type, as well as to the temperature at which the devices are actuated. However, the silk‐PPy actuators retained their functionality under all conditions tested, demonstrating the ability to bend, generate forces, and conduct currents at comparable levels to devices tested under standard operating conditions. The results suggest that our silk‐PPy actuators are promising candidates for implantation in vivo and for interfacing with biological systems. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46922.
Prospecting for cytotoxic and antiprotozoal 4‐aryl‐4H‐chromenes and 10‐aryldihydropyrano[2,3‐f]chromenes
Authors: Martin Erlon F. , Mbaveng Armelle T. , de Moraes Milene H. , Kuete Victor , Biavatti Maique W. , Steindel Mario , Efferth Thomas , Sandjo Louis P.
Published: August 2018

Different studies reported that genetic predisposition or metabolic dysfunction are the risk factors for cancer. Infectious parasitic diseases were listed among factors that predispose to cancer. Because of the resemblance between the life cycle of cancer cells and some parasites, this study aimed to prepare pyran derivatives with cytotoxic and antiprotozoal potencies. Therefore, 7 chromenes, 10 pyranocoumarins, and an unexpected intermediate were obtained from a multi‐reagent one‐pot reaction. These compounds were evaluated for their cytotoxicity on sensitive and resistant leukemia cancer cells lines and against two protozoan parasites, namely Trypanosoma cruzi and Leishmania amazonensis amastigote. Promising cytotoxicity (IC50 values of less than 1 µM) was obtained for two of the synthetic products (12 and 15). Compound 12 induced apoptosis and cell cycle arrest in CCRF‐CEM leukemia cells in G0/G1 while compound 15 and doxorubicin induced apoptosis and arrest in the S and G2/M phases. Ten of these products showed trypanocidal activity, while only five of them were weakly active on L. amazonensis. Three of the obtained pyrans showed significant cytotoxicity and antitrypanocidal activity, simultaneously. Nevertheless, all antiparasitic compounds revealed potency with low selectivity toward THP‐1 cells used as host.
rGO Functionalized with a Highly Electronegative Keplerate‐Type Polyoxometalate for High‐Energy‐Density Aqueous Asymmetric Supercapacitors
Authors: Dong Yina , Chen Li , Chen Weilin , Zheng Xiaotao , Wang Xinlong , Wang Enbo
Published: August 2018

Keplerate‐type polyoxometalates represent a large series of high nuclear molecular clusters; for example, (NH4)42[MoVI72MoV60O372(CH3COO)30(H2O)72] ({Mo132}) is a kind of spherical heteropoly blue with a large overall negative charge and an electron density and topological structure similar to C60. {Mo132} is a good bifunctional material that can be used as an electron acceptor or donor, which is advantageous to accelerate electron transmission in supercapacitors. Herein, a nanocomposite of rGO functionalized with a Keplerate‐type polyoxometalate {Mo132} was prepared by a facile chemical reduction method and used to construct supercapacitors for the first time. The electrochemical performance of the supercapacitors can be significantly improved due to the excellent redox properties, high electronegativity, and hollow porous structures of {Mo132}, in addition to the outstanding conductivity of rGO. The {Mo132}‐rGO nanocomposite electrode exhibited an excellent gravimetric specific capacitance of 617.3 F g−1 at a current density of 5 A g−1 in 1 m Li2SO4 electrolyte. An aqueous asymmetric supercapacitor with a voltage range of 2.1 V, with the {Mo132}‐rGO nanocomposite as the negative electrode and modified activated carbon as the positive electrode, exhibited a high energy density of 31.6 Wh kg−1 with a power density of 207.7 W kg−1 and favorable cycling stability.
Composite Adaptive Control of Uncertain Euler‐Lagrange Systems with Parameter Convergence without PE Condition
Authors: Basu Roy Sayan , Bhasin Shubhendu , Kar Indra Narayan
Published: August 2018

This work proposes a novel composite adaptive controller for uncertain Euler‐Lagrange (EL) systems. The composite adaptive law is strategically designed to be proportional to the parameter estimation error in addition to the tracking error, leading to parameter convergence. Unlike conventional adaptive control laws which require the regressor function to be persistently exciting (PE) for parameter convergence, the proposed method guarantees parameter convergence from a milder initially exciting (IE) condition on the regressor. The IE condition is significantly less restrictive than PE, since it does not rely on the future values of the signal and that it can be verified online. The proposed adaptive controller ensures exponential convergence of the tracking and the parameter estimation errors to zero once the sufficient IE condition is met. Simulation results corroborate the efficacy of the proposed technique and also establishes it's robustness property in the presence of unmodeled bounded disturbance.
Sliding Mode Observer Controller Design for a Two Dimensional Aeroelastic System with Gust Load
Authors: Yuan Jiaxin , Qiu Zhan , Wang Fuxin
Published: August 2018

The aim of this paper is to develop state estimation and sliding mode control schemes for the vibration suppression of an underactuated wing aeroelastic system in the presence of a gust load disturbance. Ignoring structural elastic deformation and using the concentrated elastic system (spring) to simulate the overall elastic deformation, this aeroelastic model consists of a straight wing and spring system, describing flap and pitch freedoms. The corresponding dynamic motion equation is established using the Lagrange method, and the gust is modeled as a typical “1‐cosine” gust. The aerodynamic lift and moment on the wing are computed by strip theory. The open loop system exhibits the limit cycle oscillations (LCOs) at a certain freestream velocity. The objective is to design a control system for suppressing the LCOs. For the purpose of control, a single trailing‐edge control surface is used. It is assumed that only the pitch angle is measured and the remaining state variables needed for full state feedback are estimated by the designed observer. Then an integral sliding surface is put forward on the estimation space; a new continuous reaching law is proposed to reduce the chattering phenomena. The finite‐time reachability of the predesigned sliding surface is proved and guaranteed by the designed sliding mode control law. The sufficient condition for the asymptotic stability of the closed‐loop system composed of the sliding mode dynamics and the error dynamical system is derived in terms of linear matrix inequality (LMI). The effectiveness of the proposed strategy is finally demonstrated by simulation results.
Iterative Learning Control for a Class of Fractional Order Distributed Parameter Systems
Authors: Lan Yong‐Hong , Liu Li , Luo Yi‐Ping
Published: August 2018

This paper concerns a second‐order P‐type iterative learning control (ILC) scheme for a class of fractional order linear distributed parameter systems. First, by analyzing of the control and learning processes, a discrete system for P‐type ILC is established and the ILC design problem is then converted to a stability problem for such a discrete system. Next, a sufficient condition for the convergence of the control input and the tracking errors is obtained by using generalized Gronwall inequality, which is less conservative than the existing one. By incorporating the convergent condition obtained into the original system, the ILC scheme is derived. Finally, the validity of the proposed method is verified by a numerical example.
Functional brain network centrality is related to APOE genotype in cognitively normal elderly
Authors: Wink Alle Meije , Tijms Betty M. , ten Kate Mara , Raspor Eva , de Munck Jan C. , Altena Ellemarije , Ecay‐Torres Mirian , Clerigue Montserrat , Estanga Ainara , Garcia‐Sebastian Maite , Izagirre Andrea , Martinez‐Lage Alvarez Pablo , Villanua Jorge , Barkhof Frederik , Sanz‐Arigita Ernesto
Published: August 2018

Introduction

Amyloid plaque deposition in the brain is an early pathological change in Alzheimer's disease (AD), causing disrupted synaptic connections. Brain network disruptions in AD have been demonstrated with eigenvector centrality (EC), a measure that identifies central regions within networks. Carrying an apolipoprotein (APOE)‐ε4 allele is a genetic risk for AD, associated with increased amyloid deposition. We studied whether APOE‐ε4 carriership is associated with EC disruptions in cognitively normal individuals.

Methods

A total of 261 healthy middle‐aged to older adults (mean age 56.6 years) were divided into high‐risk (APOE‐ε4 carriers) and low‐risk (noncarriers) groups. EC was computed from resting‐state functional MRI data. Clusters of between‐group differences were assessed with a permutation‐based method. Correlations between cluster mean EC with brain volume, CSF biomarkers, and psychological test scores were assessed.

Results

Decreased EC in the visual cortex was associated with APOE‐ε4 carriership, a genetic risk factor for AD. EC differences were correlated with age, CSF amyloid levels, and scores on the trail‐making and 15‐object recognition tests.

Conclusion

Our findings suggest that the APOE‐ε4 genotype affects brain connectivity in regions previously found to be abnormal in AD as a sign of very early disease‐related pathology. These differences were too subtle in healthy elderly to use EC for single‐subject prediction of APOE genotype.
Computed tomography provides enhanced techniques for longitudinal monitoring of progressive intracranial volume loss associated with regional neurodegeneration in ovine neuronal ceroid lipofuscinoses
Authors: Russell Katharina N. , Mitchell Nadia L. , Anderson Nigel G. , Bunt Craig R. , Wellby Martin P. , Melzer Tracy R. , Barrell Graham K. , Palmer David N.
Published: August 2018

Introduction

The neuronal ceroid lipofuscinoses (NCLs; Batten disease) are a group of fatal neurodegenerative lysosomal storage diseases of children caused by various mutations in a range of genes. Forms associated with mutations in two of these, CLN5 and CLN6, are being investigated in well‐established sheep models. Brain atrophy leading to psychomotor degeneration is among the defining features, as is regional progressive ossification of the inner cranium. Ongoing viral‐mediated gene therapy trials in these sheep are yielding encouraging results. In vivo assessment of brain atrophy is integral to the longitudinal monitoring of individual animals and provides robust data for translation to treatments for humans.

Methods

Computed tomography (CT)‐based three‐dimensional reconstruction of the intracranial volume (ICV) over time reflects the progression of cortical brain atrophy, verifying the use of ICV measurements as a surrogate measure for brain size in ovine NCL.

Results

ICVs of NCL‐affected sheep increase for the first few months, but then decline progressively between 5 and 13 months in CLN5−/− sheep and 11–15 months in CLN6−/− sheep. Cerebral ventricular volumes are also increased in affected animals. To facilitate ICV measures, the radiodensities of ovine brain tissue and cerebrospinal fluid were identified. Ovine brain tissue exhibited a Hounsfield unit (HU) range of (24; 56) and cerebrospinal fluid a HU range of (−12; 23).

Conclusions

Computed tomography scanning and reconstruction verify that brain atrophy ovine CLN5 NCL originates in the occipital lobes with subsequent propagation throughout the whole cortex and these regional differences are reflected in the ICV loss.
Slit‐Window Technique: An Innovation That Simplifies Lateral Sinus Floor Elevation
Authors: Ranaan Justin , Bassir Seyed Hossein , Maksoud Mohamed , Guze Kevin
Published: August 2018

Introduction

Implant placement in an atrophic posterior maxilla is challenging due to sinus pneumatization and presence of insufficient bone volume. Sinus floor elevation (SFE) is a feasible approach to increase the available alveolar bone dimensions. It is known that the maxillary sinus has a potential for healing and bone formation without the need of bone grafts or bone substitutes. However, current graft‐free sinus SFE approaches are technique sensitive and non‐reliable in consistent bone formation. This paper introduces the slit‐window technique as a novel and simple technique to perform graft‐free sinus floor elevation.

Case Presentation

A 66‐year‐old male presented with edentulous regions in the posterior maxilla and bilateral sinus pneumatization. The treatment included SFE using the graft‐free slit‐window technique on the right site and traditional lateral SFE with bone augmentation on the left site. Two implants were placed simultaneously during sinus lift procedures in each side. The slit‐window technique was performed using a rigid barrier membrane in conjunction with stabilizing bony slits to tent the Schneiderian membrane superiorly. Healing was uneventful for implants in both sides. Six months postoperatively, the amount of bone formation in the non‐grafted site was comparable to that of the grafted site.

Conclusion

Slit‐window sinus floor elevation procedure is a simple technique to elevate the floor of the sinus without the need for bone grafting.
Er,Cr:YSGG Laser Debridement of an Infected Socket for Immediate Implant Placement: A Case Report
Authors: Waasdorp Jonathan A.
Published: August 2018

Introduction

Immediate implants offer several advantages for patients, and evidence suggests they can be performed in sites with apical infection following thorough debridement. This report demonstrates the successful use of a unique erbium chromium‐doped:yttrium scandium gallium, and garnet (Er,Cr:YSGG) laser tip to degranulate a deep apical infection otherwise inaccessible to traditional instruments prior to implant placement.

Case Presentation

One case is presented where a failing mandibular left incisor with a deep peri‐apical infection was replaced with an immediate dental implant. Following removal of the tooth and debridement with conventional instruments, the socket was Er,Cr:YSGG laser‐ablated with a 26‐mm long radial firing tip. The granulation tissue was removed on the laser tip, and an immediate implant was placed which was successfully restored.

Conclusions

This report demonstrates a technique using an Er,Cr:YSGG laser with radial firing tip for debridement of extraction sites. It is a relevant, useful tool in the armamentarium as the laser energy is directed both apically and laterally. This provides a minimally invasive way to debride the site that does not entail osseous removal.
Minimally Invasive Pouch Roll Technique to Augment Peri‐Implant Soft Tissue With an 810‐nm Photoablative Diode Laser: Report of Three Cases
Authors: Giannelli Marco , Lorenzini Luca , Bani Daniele
Published: August 2018

Introduction

Second‐stage surgery for dental implant uncovering offers an opportunity to surgically correct ridge deficiencies in esthetic areas, or simply to enhance thickness of the marginal gingiva for a more stable interface with the implant. This case report illustrates an alternative laser‐aided approach to perform peri‐implant soft tissue augmentation by the pouch roll technique.

Case Presentation

Five implants in three patients with a mild horizontal ridge deficiency and minimal keratinized marginal gingiva were corrected at the time of implant uncovering using a λ 810‐nm photoablative diode laser for atraumatic selective de‐epithelialization and soft tissues incision, featuring minimal surgical trauma and patients’ discomfort.

Conclusion

Within the limitation of the small number of patients, the described method for correction of mild buccal ridge deficiencies allowed fast healing, satisfactory clinical and esthetic results, rapid prosthetic restoration and no need for local or systemic analgesics, with obvious advantages for the patients.