bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Epoxy Modifier on Flame Retardancy and Rheological Behaviour of ABS/Montmorillonite Composites
Authors: Liu Bo , Wan Chaoying , Zhang Yong , Zhang Yinxi , Su Yu , Ji Jiliang
Published: September 2018

Acrylonitrile–butadiene–styrene resin (ABS) composites were prepared by melt intercalation of organically modified montmorillonite (OMMT) with or without pre-treatment by liquid epoxy resin. The morphology, flame retardancy and rheological properties of the composites were studied. Morphology observation using X-ray diffractometer (XRD) and transmission electron microscopy (TEM) reveals that the processing conditions used for epoxy modification have a great influence on the morphology and structure of the composites. With the direct addition of epoxy, the ABS/MMT composite has an intercalated structure; while with the pre-treatment of MMT with epoxy, the composite has an exfoliated structure in which MMT is well dispersed at nano-scale. Cone analysis results show that those composites with an intercalated structure have a slightly lower heat release rate (HRR) than the ones with an exfoliated structure, indicating a slight difference in flame retardancy between the two. The viscoelastic behaviour of the composites was measured by using a parallel plate rheometer. In the low frequency zone, the composites with an exfoliated structure exhibited a distinct storage modulus plateau and a solid-like response, and they had a higher storage modulus and viscosity than the ones with an intercalated structure.
Carrageenan-g-Poly(sodium Acrylate)/Kaolin Superabsorbent Hydrogel Composites: Synthesis, Characterisation and Swelling Behaviour
Authors: Pourjavadi A. , Hosseinzadeh H. , Mahdavinia G.R. , Zohuriaan-Mehr M.J.
Published: September 2018

A novel superabsorbent hydrogel composite based on kappa-carrageenan (κC) was prepared by graft copolymerisation of acrylic acid (AA) in the presence of kaolin using methylenebisacrylamide (MBA) as a crosslinking agent and ammonium persulfate (APS) as an initiator. The synthetic variables (i.e. AA, MBA and APS concentration, and the amount of kaolin) affecting the water absorbency of the resulting superabsorbent composite were studied. Evidence of grafting and kaolin interaction was obtained by comparing the FTIR spectra of the initial substrates and of the superabsorbent composite. A new absorption band at 1722 cm−1 in the composite spectrum confirmed the kaolin-organic polymer linkage. Increasing the amount of kaolin and the MBA concentration caused the water absorbency of the superabsorbent composite to decrease. The effect of various salt media and pH on the swelling of the superabsorbent was studied. The swelling kinetics of the synthesised composite was also investigated.
Prediction of Deformation of Asymmetric Hybrid Composites from Cure Monitoring Results of Non-Hybrid Composites
Authors: Jung Kyungho , Kang Tae Jin , Kim Jae-Hong , Park Jong Kyoo , Lee Byoungho , Kim Youngmin
Published: September 2018

The prediction and estimation of residual stress in the fabrication of hybrid composites is one of the most important issues relating to these materials. The dimensional changes in three carbon woven fabric/phenolic composites were estimated using embedded sensors during cure. The contributions of the cure shrinkage and thermal contraction to the dimensional changes were separately assessed. The out-of-plane deformation of three asymmetric interply hybrid composites was predicted using FEM analysis based on the curing monitoring results, and it was also estimated experimentally using a 3-D scanning system. In the exceptional case that two constituents of an asymmetric hybrid composite had similar shrinkage, the experimental and numerical results exhibited quite a large difference, although they agreed well for general cases.
The Effect of Tri(n-butyl) Tin(IV) –2– [3–Benzoyl phenyl] Propionate on the Degradation and Stabilisation of PVC in Inert and Oxidative Atmospheres
Authors: Iqbal Azhar , Ishaq Muhammad , Sarwar Muhammad Ilyas , Frormann Lars
Published: September 2018

Tri(n-butyl) tin(IV)–2–[3–benzoyl phenyl] propionate has been used to enhance the shelf life of rigid poly (vinyl chloride) (PVC). Studies of the thermal degradation of PVC have been a prime focus for a long time. Different substances have been tried to control and stabilise the process of thermal degradation. In the present work the aforementioned stabiliser has been used for this purpose. The samples of PVC containing different amounts of the stabiliser were prepared and treated at 190 ± 3 °C. The effect of the stabiliser on the degradation in nitrogen and air environments was studied through conductometric and spectroscopic measurements.

The stabiliser was effective in slowing down the process of degradation. It also increased the initial induction period, i.e. the time during which no sign of degradation were observed. About 3% of stabiliser reduced the rate of the degradation of PVC by half, and almost doubled the induction period. It was more efficient in nitrogen than in air. These findings indicate that tri(n-butyl) tin(IV)–2–[3–benzoyl phenyl] propionate is a good inhibitor as well as an effective retarder.
Preparation of Nanometre Carbon Fibres by Using a Blend Approach
Authors: Zhang Wang-xi , Wang Yan-zhi
Published: September 2018

PMMA/PAN core/shell microspheres were synthesised by polymerising methyl methacrylate (MMA) or acrylonitrile(AN) at 75 °C for 5 h in a soapless emulsion system, using ammonium persulfate (APS) as a radical initiator. It has been shown that in the first-stage reaction the initiator APS significantly accelerated the reaction rate. However, when the APS concentration reached 0.9% (based on the amount of the monomers), this tendency lessened.

In the second-stage core/shell reaction, the effect of initiator on reaction rate was not so pronounced. Transmission electron microscope (TEM), fourier transform infrared (FT-IR), thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) were used to characterise the structure and properties of seeded PMMA core and/or PMMA/PAN core/shell polymers. The core/shell morphology was clearly displayed and the diameter of the core is ca. 350 nm whereas the shell thickness was ca. 100 nm. Both the PMMA core and the PMMA/PAN core/ shell polymers had weak and strong endothermic peaks when heated in the range of 340–390 °C, but the latter showed a characteristic exothermic peak which corresponded with the crosslinking reaction of polyacrylonitrile macromolecules at ca. 600 °C. A mixture was obtained by blending the core/shell polymers with high density polyethylene, then spinning to form composite fibres, which were thermally stabilised in air at 180 °C for 1 h and carbonised in nitrogen at 1000 °C to obtain nanometre-sized carbon fibres.
Effect of Epoxy-Functionalised Core-Shell Particles on Properties of Poly(Butylenes Terephthalate) (PBT)
Authors: Wu Guangfeng , Ji Wei , Sun Shulin , Zhang Huixuan
Published: September 2018

Glycidyl methacrylate (GMA) functional core-shell impact modifiers of butyl acrylate as a core and methyl methacrylate as a shell (gACR) have been prepared by a multi-step seeded emulsion polymerisation. FTIR spectroscopy results show that GMA had been grafted onto ACR and the GMA content in gACR was measured by titration of the epoxy groups. DMA was used to characterise the mechanical properties of the PBT/gACR blends. DSC results showed that the melting point of PBT shifted to lower temperature with an increase in GMA content. Scanning electron microscopy (SEM) images showed that the dispersion of gACR in PBT was uniform. The optimum recipes for gACR toughened PBT had a GMA content of 3% (wt) in gACR resins. The gACR particle size was about 350 nm and the gACR content was 20% (wt) in PBT resins. The notched impact strength of PBT/gACR blends exceeded 440 J/m. It was confirmed that functional core-shell impact modifiers are efficient in toughening PBT.
Modelling of Strength and Stiffness Behaviour of Natural Fibre Reinforced Polypropylene Composites
Authors: Taha I. , El-Sabbagh A. , Ziegmann G.
Published: September 2018

The mechanical behaviour (strength and stiffness) of natural fibre reinforced thermoplastics is investigated on the example of an injection moulded sisal-polypropylene system. An analytical model based on the rule of mixtures is developed to predict the mechanical behaviour of such composites. Considering interfacial characteristics this model accounts for the different modes of load transfer between matrix and fibre and their changeover. Close agreement between model and experimental results was achieved at low fibre contents (below 20 wt.%) as well as at higher contents (exceeding 40 wt.%). The model was finally verified against the experimental data and against available literature results.
Kinetic Model for the Thermal Degradation of Poly(Methylphenylsiloxane)
Authors: Sun J.T. , Huang Y.D.
Published: September 2018

The kinetics of the thermal degradation of polymethylphenylsiloxane (PMPS) were investigated by dynamic thermogravimetric analysis. The thermal degradation of PMPS has two processes: “unzipped degradation” and “rearranged degradation”. The corresponding kinetic parameters of the two stages were determined using the Kissinger and Friedman methods respectively. The results showed that the value of the activation energy (E) obtained from the Friedman method was in good agreement with that obtained by the Kissinger method. For “unzipped degradation”, E was 164.2 kJ/mol and 168.2 kJ/mol, and for “rearranged degradation”, E was 228.6 kJ/mol and 232.0 kJ/mol. The Arrhenius pre-exponential factor (A) and reaction order (n) for the two stages were also discussed. A kinetic model was built by using the obtained kinetic parameters, and the results obtained by the model were in good agreement with the measured value.
Preparation and Characterisation of Epoxy Composites Filled with Silica Nanoparticles
Authors: Ou Cheng-Fang , Shiu Ming-Chin
Published: September 2018

A series of epoxy/SiO2 composites, containing 0.5, 1, 3, 5, and 7 wt.% SiO2 nanoparticles, were prepared by solution blending. Differential scanning calorimetry (DSC) indicated that the glass transition temperatures (Tg) of the composites were higher than that of the pure epoxy and rose as the SiO2 content increased. The decomposition temperatures (Td) of the composites were always higher than that of the pure epoxy, the maximum increase of 20.8 °C being achieved with the addition of 5 wt.% SiO2. The light transmittance of the composites was still higher than 80% with up to 7 wt.% SiO2. The water permeability of the composites decreased with increasing SiO2 content, and the 7 wt.% SiO2 produced a composite with the maximum permeability decrease of 56.3%. Scanning electron microscopy (SEM) showed that finer silica was dispersed in the epoxy matrix without large agglomerates.
Preparation and Characterization of Polyurethane/Multiwalled Carbon Nanotube Composites
Authors: Guo Shuzhong , Zhang Chao , Wang Weizhi , Liu Tianxi , Tjiu Wuiwui Chauhari , He Chaobin , Zhang Wei-De
Published: September 2018

Multiwalled carbon nanotube (MWNT)/polyurethane (PU) nanocomposites have been prepared by the combination of in-situ polymerization and solution-casting approach. A homogeneous dispersion of MWNTs throughout PU matrix is observed by scanning electron microscopy on the fracture surfaces of the composites. Strong interfacial adhesion between the MWNTs and the PU matrix, as evidenced by the presence of broken but strongly embedded MWNTs in the matrix, is favorable to stress transfer from polymer matrix to the nanotubes. Mechanical tests (by tensile testing and dynamic mechanical analysis) show that, compared with neat PU, both the Young's modulus and the tensile strength of the composites are significantly improved by about 90%, with incorporating only 1 wt.% MWNTs. And most importantly, the elongation-at-break of PU/carbon nanotube (CNT) composites is greatly improved by about 500%, indicating that the toughness of neat PU is remarkably enhanced by adding CNTs into the matrix. The fine dispersion of CNTs and strong interfacial adhesion between the CNTs with the matrix are responsible for the simultaneous and significant enhancement in the strengthening and toughening of PU matrix. In addition, the thermal stability of PU was also improved after incorporating CNTs into the matrix.
Research on Fiber Placement Trajectory Design Algorithm for the Free-Form Surface with Given Ply Orientation Information
Authors: Peiyuan Wang , Yong Li , Xianfeng Wang , Jun Xiao
Published: September 2018

Aiming at the traditional fixed-angle trajectory design methods in automatic composite fiber placement, a novel trajectory design algorithm based on given ply orientation information of the free-form surface is proposed. Firstly, the initial reference path is constructed with the given points and modified fiber-placement directions that are calculated by weighted average algorithm. Then, “feature section” method is carried out to solve the full-spreadability issue and all other center paths are generated by the parallel equidistant path generation method based on geodesic theory of the classic differential geometry. Finally, the Newton-Raphson iteration algorithm is applied to solve the intersection issue between fiber path and boundary, which can realize the integrated placement at the boundary area. Based on the above algorithms, the CAD module of the trajectory planning for the free-form surface with given ply orientation information is developed with the environment of CATIA V5R18, and is validated by simulations. The results show that the above algorithms can accomplish the trajectory design based on the ply orientation information and make a positive exploration on the variable angle trajectory design in automatic fiber placement.
Simulation Study of Fracture Behavior in a FMLs Specimen by 3D Elastic-Plastic Finite Element Model
Authors: Xin Song , Zheng Liu , Jiazhen Zhang
Published: September 2018

Fiber metal laminates (FMLs) commonly occur in airplane structures and are of great interest in the aerospace industry due to their superior properties. This study simulates fracture behavior in a FMLs specimen subjected to quasi-static loading conditions by a 3D elastic-plastic finite element model in ABAQUS. Cohesive elements are used to model the interlaminar delamination, and the ABAQUS damage model for fiber-reinforced materials is used to predict behavior of the fiber-reinforced epoxy layer. The materials strength can be predicted by the simplified 3D elastic-plastic finite element model. Predictions accuracy of model are tested by the experimental results and good consistency acquired. The models presented in this study can shorten the period of new style FMLs research and the cost cut down largely.
Compressive Property of Basalt Fiber in Composite with Nano-indentation
Authors: Tong Lili , Zhou Limin , Wang Zhenqing
Published: September 2018

The compressive property of a single basalt fiber in basalt/epoxy and basalt/PCBT composite was investigated by nano-indentation with the application of conical-pyramidal Berkovich tip. The nano-indentation test involved a load from 30 mn to 200 mn. Every indent was produced on section of a single fiber. Area function was selected according to the depth of the indent. The results showed that compressive modulus and hardness of basalt fiber is higher than those of glass fiber and carbon fiber in the same matrix. The modulus of basalt fiber behave differently when embed in different matrixes.
Experimental and Numerical Study of Tool Effect on Curing Deformation for the Composite Missile Structure
Authors: Jinrui Ye , Guangquan Yue , Boming Zhang , Shan Lu , Kai Cheng
Published: September 2018

Composite missile structure is complicated in shape and fabricated by soft-film-assisted Resin Transfer Molding (RTM). The cylindrical tool of composite missile structure was studied in the paper. A completed method of analyzing and estimating the tool deformation was presented. The analysis models and three-dimensional finite element method (FEM) for cure process of composite integrated structure were developed. Thermal deformation and cure shrink were considered in analysis models and the evolution of residual stresses in the entire cure process was studied. The strain and temperature fields in the cylinder-shaped mold of composite missile structure were measured respectively using optical fiber grating and thermocouple. The experimental results show a good agreement with the finite element analysis. The deformation of the tool is added to the composite missile simulation model as a displacement loading to analyze the effects of the tool's curing deformation on the part. The results are valuable for the tool design, tool deformation control, and elimination for the composite missile structure.
Research on Stability Condition of Polar Winding on the Dished Head
Authors: Wang Rongguo , Yang Fan , Liu Wenbo , Jiao Weicheng , He Xiaodong
Published: September 2018

The polar winding, as a kind of non-geodesic winding, is in a serious slippage trend. Based on the Theoretical Model of the filament winding, this paper outlines a kind of numerical methods for determining the stability condition of the polar winding on the composite pressure vessel with dished head. At last, through the providing some examples, this paper shows the stable trend on the dished dome during polar winding to optimize the design result.
Compatibility and Anti-oxidation Properties of Study on Liquid Oxygen Compatibility with Nano-modified Epoxy Composites
Authors: Wang Rongguo , Zhang Chenwei , Liu Wenbo
Published: September 2018

Nano-sized silica particles were synthesized by sol-gel reaction. Epoxy resin/nano-silica composites were prepared by high-speed mixing after ultrasonic dispersion. By using electron microscopy and scanning electron microscope (SEM) techniques, the particle dispersion in the epoxy resin/nano-silica composites is studied. Anti-oxidation properties of the materials were investigated by thermogravimetric analysis (TGA) in the oxygen. The compatibility of the nano-composites with liquid oxygen was ranked according to the liquid oxygen sensitivity impact test results by the ASTM D2512 liquid oxygen (LOX) impact test. The results showed that the nano-modification method can significantly improve the liquid oxygen compatibility of epoxy composites.
Swelling Behavior Study of Physically Crosslinked Gelatin Hydrogels
Authors: Qiao Congde , Cao Xiaolu , Wang Fei
Published: September 2018

A series of physically crosslinked gelatin networks were prepared and the effects of salt, pH, temperature and polymer concentration on the swelling properties of gelatin hydrogels were studied in detail. The swelling equilibrium of the gelatin networks can be described as a simple superposition of polyelectrolyte behavior and polyampholyte behavior. It was found that high temperature, low gelatin concentration and deviation from the isoelectric point can promote the swelling of the polymer networks. Moreover, the swelling kinetics of gelatin hydrogels at different salt concentration solutions was also investigated. It is found that the rate of swelling of gelatin could be described by a second-order rate equation, which indicated that the structure of the gelatin networks is homogenous.
Preparation of Epoxy Sizing Agent for Carbon Fiber by Phase Inversion Emulsification
Authors: Liu Jianye , Ge Heyi , Chen Juan , Liu Huashi
Published: September 2018

The epoxy resin and epoxidized polybutadiene were used to prepare the emulsion type epoxy sizing agent for carbon fiber by phase inversion emulsification method. Effects of weight ratio of mixed emulsifiers and emulsifiers/resin (ωe/r), shear rate and dripping speed of water on properties of emulsion were investigated by centrifugal sedimentation analysis, particle size analysis and zeta potential measurement. Results showed that the optimal emulsion was obtained when weight ratio of polyoxyethylene nonylphenol phosphoric ammonium (NP-10A) and polyoxyethylene styrenated phenol ether (602) was 2:1, ωe/r was 12%, shear rate was 10000 r/min. Conductivity of emulsion by different ωe/r was also investigated to represent the variation of conductivity during emulsification process.
Flexed-plate Low Energy Impact of an Epoxy-Carbon Fibre Laminate
Authors: Martínez A.B. , Xiang G. , Arencón D.
Published: September 2018

A model for predicting the contact duration, force, indentation, displacement and restitution coefficient has been developed for the low energy impact with an hemispherical tip of a composite laminated plate. The model is based in the Hertz law and the thin plate small deflection theory. The governing equations for the motion were first proposed and then solved. Several tests were conducted using two weight drop tower testers with different test geometries. Comparison between the model predictions and the experimental results shows a very good agreement between the modelled and the experimental forces, contact times, displacements, depth of penetration and restitution coefficients.
Friction and Wear of Epoxy Composites Containing Silica Nanoparticles Grafted by Hyperbranched Aromatic Polyamide
Authors: Yu Ying , Rong Min Zhi , Zhang Ming Qiu
Published: September 2018

Nano-sized SiO2 particles grafted with hyperbranched aromatic polyamide were employed as fillers for fabricating epoxy based composites. The hyperbranched aromatic polyamide was selected because its terminal amine groups could take part in the curing reaction of epoxy resin and covalently connect silica nanoparticles with the matrix. The experimental results proved the occurrence of this reaction, and indicated that the presence of the grafted SiO2 in epoxy does not change the overall curing mechanism of epoxy. In comparison to the composites filled with untreated nano-SiO2 particles, the composites with the grafted nano-SiO2 exhibited significantly improved sliding wear resistance and reduced frictional coefficient owing to the strong filler/matrix interfacial bonding. Moreover, hyperbranched aromatic polyamide grafted nano-SiO2 was more effective to enhance tribological properties of epoxy than linear polymers grafted versions.
Effect of Molecular Weight of Polycarboxylate-type Superplasticizer on the Rheological Properties of Cement Pastes
Authors: Peng Xiongyi , Yi Conghua , Qiu Xueqing , Deng Yonghong
Published: September 2018

In order to study the effect of molecular weight of polycarboxylate-type superplasticizer (PC) on the rheological properties of cement pastes, PCs with different molecular weights (low, medium, high) were synthesized, and used as superplasticizers for cement suspensions. The effect of molecular weight of PC on the zeta potential, adsorption, and rheological behaviour of the corresponding cement suspensions were investigated systematically. Among the PCs, PC with a medium molecular weight always produced the lowest apparent viscosity for cement pastes at the same shear rate. Compared to PC with a low molecular weight, PC with a high molecular weight presented a stronger initial dispersing ability and a weaker dispersing stabilizing ability for cement pastes. In addition, PC with a low molecular weight had an advantage over PC with a high molecular weight for reducing the viscosity of paste in the low added dosage or low water/cement ratio, but the latter had the advantage of reducing the viscosity of the paste when the added dosage or water/cement ratio was high. This understanding of the rheological properties of cement pastes incorporating PC will provide an important reference for the application and synthesis of PC with high efficiency.
Tensile and Impact Properties of Different Morphological Parts of Sugar Palm Fibre-Reinforced Unsaturated Polyester Composites
Authors: Sahari J. , Sapuan S.M. , Ismarrubie Z.N. , Rahman M.Z.A.
Published: September 2018

The present study investigated the tensile and impact behaviour of unsaturated polyester composites reinforced by fibre from different parts of the sugar palm tree. Sugar palm fibre i.e. sugar palm frond (SPF), sugar palm bunch (SPB), black sugar palm fibre ( ijuk) and sugar palm trunk (SPT) which have high content of cellulose, low density, abundance and low cost, have the potential for polymer reinforcement. All composites were fabricated and labelled as SPF/PE, SPB/PE, ijuk/PE and SPT/PE. It was found that SPF/PE had the highest tensile strength which was 15.179 MPa (±2.425) followed by SPB/PE, ijuk/PE and SPT/PE with 12.809 MPa (±1.580), 11.473 MPa (±0.536) and 9.817 MPa (±1.890) respectively. For the impact strength analysis, SPF/PE showed the highest value (8.091 kJ m-2). Generally, SPF/PE had better tensile and impact properties than the other composites, due its high cellulose content.
Effect of Audit and Feedback on Physician Adherence to Clinical Practice Guidelines for Pneumonia and Sepsis
Authors: Trent Stacy A. , Havranek Edward P. , Ginde Adit A. , Haukoos Jason S.
Published: September 2018

The objective was to estimate the effect of feedback with blinded peer comparison on emergency physician adherence to guidelines for appropriate antibiotic administration for inpatient pneumonia and completion of the 3-hour Surviving Sepsis Bundle for severe sepsis. The authors performed a quasi-experiment using a stepped wedge design at a single urban safety net hospital. Attending emergency physicians were randomized into 6 clusters. Once a cluster crossed into the intervention group, physicians in that cluster began receiving detailed feedback with blinded peer comparison on their adherence to guidelines for pneumonia and sepsis. Feedback with blinded peer comparison significantly improved guideline adherence from 52% without feedback to 65% with feedback (difference = 13%, 95% confidence interval = 4% to 22%). In adjusted analyses, the odds of providing guideline adherent care were 1.8 (95% confidence interval = 1.01-3.2) after the introduction of feedback with blinded peer comparison. Feedback with blinded peer comparison significantly improved emergency physician guideline adherence.
Behavior-Specific Praise: An Effective, Efficient, Low-Intensity Strategy to Support Student Success
Authors: Ennis Robin Parks , Royer David James , Lane Kathleen Lynne , Menzies Holly M. , Oakes Wendy Peia , Schellman Liane Elizabeth
Published: September 2018

Behavior-specific praise (BSP) is a low-intensity strategy that can be used to reinforce appropriate responding in the classroom. BSP occurs when a teacher observes particular student behavior and compliments the student for the appropriate response with the intent that students will continue to engage in the appropriate behavior. In this article, we describe a step-by-step process for using BSP in classrooms with all students, including those at risk for emotional and behavioral disorders.
Antimicrobial activity of essential oils against foodborne multidrug-resistant enterococci and aeromonads in planktonic and biofilm state
Authors: Quendera Ana P , Barreto António S , Semedo-Lemsaddek Teresa
Published: September 2018

The selection and use of natural compounds with antimicrobial activity against foodborne pathogens is of major importance. The present study evaluated the antimicrobial activity of commercial essential oils against multidrug-resistant Enterococcus spp. and Aeromonas spp. Cymbopogon flexuosus and Thymus vulgaris essential oils presented the highest inhibitory zones against both bacterial groups ( p < 0.05). Subsequent determination of the minimum inhibitory concentrations showed values between 0.47 and 1.9 mg/ml for Aeromonas spp. and from 1.9 to 15 mg/ml for Enterococcus spp. The antimicrobial effect of C. flexuosus and T. vulgaris essential oils was also assessed against biofilms. Bacteria in biofilm state were subjected to 30 min or 1 h of exposure to each essential oil and eradication ability estimated by colony counting. Both essential oils exhibited antimicrobial activity against preformed Aeromonas biofilms, but were unable to successfully eradicate biofilms produced by enterococci, in the conditions under investigation. Nonetheless, the presumptive use of essential oils in the food industry should be considered in further investigations.
Postmortem Diagnosis of Heart-hand Syndrome Associated With a 7p22.1p22.3 Deletion in a 16-week-old Fetus
Authors: Tessier Aude , Callier Patrick , LeMeur Nathalie , Frebourg Thierry , Sabourin Jean-Christophe , Patrier Sophie
Published: September 2018

We report a male fetus with a 6.8 Mb deletion on chromosome 7p22.1p22.3 at 16 weeks of gestation. The fetus presented a heart-hand syndrome with great artery malposition, bilateral radial ray deficiency, a single pelvic kidney, and growth retardation. This deletion involves a minimal deleted region for cardiac malformation and the RAC1 gene, previously described in limb anomalies in mice. This fetus is the third human case with limb defects and RAC1 deletion.
(Re)defining disability culture: Perspectives from the Americans with Disabilities Act generation
Authors: Forber-Pratt Anjali J
Published: September 2018

The present study examined the views of students with varying physical disabilities on disability culture in a post-Americans with Disability Act society. Qualitative, participatory research methods were used to observe approximately 30 disabled students and conduct in-depth interviews with four disabled students. The main objective was initially to answer the following question: Do disabled students recognize an identifiable disability culture at that particular university, and if so, what does it look like? While the sheer presence of disabled students does not automatically equate to a robust disability culture, it became apparent that there was a disability culture at this site, and therefore the research question was refined to: What are the features of disability culture according to this population? The participants were all students at an institute of higher education in the Midwestern United States. The researcher self-identifies as having a disability. Using in vivo coding for analysis to preserve the voices of the participants themselves, the results indicated that there was a disability culture and the key values defining this culture included independence, social justice, and giving back to others.
The effect of education through mobile phone short message service on promoting self-care in pre-diabetic pregnant women: A randomized controlled trial
Authors: Abbaspoor Zahra , Amani Anis , Afshari Poorandokht , Jafarirad Sima
Published: September 2018

Introduction

Gestational diabetes is increasing in developed and developing countries. This study aimed to evaluate the effect of SMS messaging on the self-care among pre-diabetic pregnant women.

Methods

This randomized controlled trial conducted on 100 pre-diabetic pregnant women referred to Ahvaz Health Centers, Iran, Sep to Dec, 2016. Women were randomly assigned into the face to face education group and short message systems in addition to the face to face education group. Self-care variables were compared between the groups. Data was analyzed using chi-square, independent and paired t-tests.

Results

There was no difference regard to FBG and OGTT, but there was a significant difference between groups in physical activity level ( P<0.001) and in all food groups except bread and cereals after the intervention ( P<0.05).

Conclusion

The education through a short text message system seem couldn't control the blood sugar, but it could promote physical activity and food additives of pre-diabetic pregnant women.
Impact of telemedicine on the clinical outcomes and healthcare costs of patients with chronic heart failure and mid-range or preserved ejection fraction managed in a multidisciplinary chronic heart failure programme: A sub-analysis of the iCOR randomized trial
Authors: Jiménez-Marrero Santiago , Yun Sergi , Cainzos-Achirica Miguel , Enjuanes Cristina , Garay Alberto , Farre Nuria , Verdú Jose M , Linas Anna , Ruiz Pilar , Hidalgo Encarnación , Calero Esther , Comín-Colet Josep
Published: September 2018

Background

The efficacy of telemedicine in the management of patients with chronic heart failure and left ventricular ejection fraction ≥40% is poorly understood. The aim of our analysis was to evaluate the efficacy of a telemedicine-based intervention specifically in these patients, as compared to standard of care alone.

Methods

The Insuficiència Cardiaca Optimització Remota (iCOR) study was a single centre, randomised, controlled trial, designed to evaluate a telemedicine intervention added to an existing hospital/primary care multidisciplinary, integrated programme for chronic heart failure patients. 178 participants were randomised to telemedicine or usual care, and were followed for six months. For the present sub-analysis, only iCOR participants (n = 116) with left ventricular ejection fraction ≥40% were included. The primary study endpoint was the incidence of an acute non-fatal heart failure event, defined as a new episode of worsening of symptoms and signs consistent with acute heart failure requiring intravenous diuretic therapy. The healthcare-related costs in each study group were also evaluated.

Results

The incidence of the first occurrence of the primary endpoint was significantly lower in the telemedicine arm (22% vs 56%, p<0.001), with a hazard ratio of 0.33 comparing to the usual care arm (95% confidence interval 0.17–0.64). Telemedicine was also associated with lower mean overall chronic heart failure care-related costs compared to usual care (8163€ vs 4993€, p=0.001). The results were consistent in both left ventricular ejection fraction of 40–49% and left ventricular ejection fraction ≥50% patients.

Conclusions

Our results suggest that telemedicine is a promising strategy for the management of chronic heart failure patients with left ventricular ejection fraction ≥40%. These findings should be replicated in larger cohorts.
Gas-phase metal ion chelation investigated with IRMPD spectroscopy: A brief review of Robert Dunbar’s contributions
Authors: Oomens Jos , Polfer Nicolas C , Berden Giel , Eyler John R
Published: September 2018

With the passing of Prof. Robert C. Dunbar on 31 October 2017, the field of ion chemistry lost one of its modern heroes. Throughout his career in mass spectrometry, two of his main research interests involved the interaction of trapped ions with electromagnetic radiation and the chelation motifs of metal ions with organic ligands. The focus of his early career was on the fundamental processes that take place in molecules upon ultraviolet and infrared excitation. From 2003 to 2017, his scientific interests shifted to more structural questions, notably to resolving the structures and binding motifs of metal ion chelation complexes by application of infrared photodissociation spectroscopy. These experiments were carried out during numerous visits to the (Free Electron Laser for Infrared eXperiments) (FELIX) facility in the Netherlands and were complemented by extensive theoretical investigations by Rob. As a tribute to our friend, we present in this contribution a brief review of this work.
A mixed methods systematic review of multimodal non-pharmacological interventions to improve cognition for people with dementia
Authors: Chalfont Garuth , Milligan Christine , Simpson Jane
Published: September 2018

Objective

Multimodal non-pharmacological interventions have been argued to have the potential to complement current pharmacological approaches to improving quality of life for people living with dementia. The aim of this review was to identify, synthesise and appraise the evidence for the effectiveness of multimodal non-pharmacological interventions for improving cognitive function specifically.

Method

After a comprehensive search strategy including grey literature, 26 studies were reviewed. The inclusion criteria concerned adults with a primary diagnosis of dementia. Studies used two or more different modes of intervention, and measured a cognitive outcome. Due to differences in the conceptualisations of the term ‘multimodal’, a typology of modes and methods was developed to facilitate classification of candidate studies.

Results

Twenty-one group studies and five case studies were found. Group studies used two or three modes of intervention and multiple methods to implement them. Interventions utilised were cognitive, physical, psychological and psychosocial, nutrition, fasting, gut health, sleep hygiene, stress reduction, detoxification, hormonal health and oxygen therapy. Five individual case studies were found in two separate papers. Each personalised patient treatment utilised in-depth assessments and prescribed up to nine different modes. In 19 (90%) of the 21 group comparisons, participants were reported to have cognitive improvements, stability with their dementia or a delay in their decline. The extent of these improvements in terms of meaningful clinical change was variable.

Conclusion

Multimodal non-pharmacological interventions have the potential to complement singular therapeutic approaches by addressing multiple modifiable risk factors currently understood to contribute towards cognitive decline.
Contaminants and their Levels of Retention in Extruded, Recycled Poly(Ethylene Terephthalate) from Curbside Collection. Part 1: Extraction Kinetics and Particle Size Effects
Authors: Konkol L.M. , Cross R.F. , Harding I.H. , Kosior E.
Published: September 2018

In the first phase of our studies of the contaminants and their levels in curbside-collected poly(ethylene terephthalate) (PET) subjected to a recycling process, we analysed the washed and dried, shredded PET (flake). Of the semi-volatile contaminants found, 26 were below the US FDA threshold of 215 ppb and six were above. Additionally, it was found that surface levels of contaminants far exceeded average concentrations in the bulk of the flake, raising questions about the appropriateness of sampling procedures. In this second phase (again using dichloromethane Soxhlet extractions for the most part), we examined contaminant levels after the flake was subjected to vacuum extrusion, to complete the recycling process. Initially amorphous, extruded pellets were annealed to introduce crystallinity and allow grinding, in order to examine the effect of particle size. Much reduced concentrations of contaminants were found (all <215ppb). There were no significant differences in contaminant levels as a function of particle size, thus indicating a uniform distribution throughout the extruded material and no need for particle size reduction before sampling and analysis. However, whilst 3 h was sufficient to obtain quantitative extractions from the ground, annealed particles in each size range (0-300 μm, >300-425 μm and >425-700 μm), approximately 8 h were required for the unground annealed pellets.
Mechanical and Dynamic Mechanical Properties of Vinyltriethoxysilane Grafted EPDM-g-VTES/LLDPE Blends
Authors: Alagar M. , Majeed S.S.M. Abdul , Premkumar S.
Published: September 2018

The mechanical and dynamic mechanicalproperties of vinyltriethoxysilane (VTES) grafted ethylene propylene diene terpolymer/linear low density polyethylene (EPDM-g-VTES/LLDPE) blends have been evaluated with special reference to the effect of blend ratio. Mechanical properties such as tensile strength, Young's modulus and hardness increase with increase in LLDPE content in the blends and with increasing concentration of dicumyl peroxide (DCP), whereas the elongation at break decreases. Increasing the amount of LLDPE in the blends increases the storage and loss moduli because of the improvement in crystallinity.
Use of Recycled Tyre Material in Natural Rubber-Based Tyre Tread Cap Compound: Part I
Authors: Bandyopadhyay S. , Agrawal S. L. , Mandot S. K. , Mandal N. , Dasgupta S. , Mukhopadhyay R. , Deuri A.S. , Ameta Suresh C.
Published: September 2018

For both environmental and economic reasons, there is a continuing broad-based interest in recycling of scrap rubber and in the development of recycling technologies. Among all the polymeric materials, the reuse of rubber vulcanisate is the most difficult, being thermosetting in nature the crosslinks formed are not easily broken down. In the present work, three different types of recycled materials (coarse reclaim, superfine reclaim and de-vulcanised rubber) were used in a natural rubber (NR) based bias tyre tread cap compound. Various quantities of the above ingredients were used as a replacement for virgin natural rubber. Chemical characterisation of the recycled material, the mixed rubber compound rheometric properties, unaged and air-aged stress strain properties, hardness, fatigue to failure, Demattia crack initiation, crack propagation, abrasion loss, volume fraction, rebound resilience, elastic modulus and dynamic mechanical properties were performed. In all levels of usage, the superfine reclaim rubber retained the properties to a greater extent when compared to the other recycled materials used in the study.
Incorporation of Waste Textile Fabric in High Density Polyethylene Matrix
Authors: Finkler Maira , Nunes Regina C.R. , Zattera Ademir J. , Zeni Mara
Published: September 2018

An alternative approach for the reuse of waste textiles fabric (WTF) of cotton and polyacrylonitrile was investigated with the purpose of to reinforce high density polyethylene (HDPE) and in addition, a new methodology for obtaining the composites was also developed. It was found that the resulting mechanical properties tested were function of the fibers content. In order to improve the performance of these composite materials, 5 phr (part hundred resin) of maleic anhydride grafted high density polyethylene (HDPEgMAH) was used as compatibiliser. It is believed that the addition of a reactive compatibilizer to the system increased both the compatibility among components of the composite material and interfacial interactions.
Effect of Chemically Treated Buffing Dust on Technological Properties of Tyre Tread Compounds
Authors: Wellappili Champa J. , de Silva Karnika , Dharmatilake Malani , Denawaka Indra
Published: September 2018

Polymer blends have become a very important subject for scientific investigation because of their growing commercial acceptance. This research aimed to investigate the possibilities of blending chemically treated buffing dust, a cheap reinforcing filler in virgin natural rubber (NR) systems to obtain improved properties. A series of experiments were carried out with three types of blend - namely NR with untreated buffing dust, fatty acid (FA) treated buffing dust and De-link treated buffing dust.

Pre-conditioning of buffing dust by treating with De-link showed improvements in all properties when compared to blends with untreated buffing dust. Further improvement of physical properties was achieved through a blending process where buffing dust was first treated with a FA, before the actual blending with NR compound was carried out. FA based activator seems to improve the miscibility of the two phase through possible plasticizing action thereby improving the physical properties of the end product. It is clear that the incorporation of the FA could be a cheaper alternative to achieve better dispersibility of buffing dust in NR phase to improve the properties of blends.
Investigation on Ageing Characteristics of Short Nylon-6 Fibre Reinforced NBR Composites
Authors: Rajesh C. , Manoj K.C. , Unnikrishnan G. , Purushothaman E.
Published: September 2018

The ageing characteristics of nylon 6 fibre reinforced NBR composites have been analysed by exposing them to degrading agents such as heat and gamma (γ) radiation. The effects of fibre loading, curing systems and bonding agents on the retention of tensile properties of the composite samples which were exposed to these degrading agents have been studied. The addition of fibres improves the ageing resistance of NBR. The DCP cured composites exhibit a reduction in their ability to retain the elastic modulus as the thermal ageing period increases from 7 to 14 days, whereas sulfur cured composites show a reverse trend. The efficiency for the retention of modulus of sulfur cured samples increases as the dosage of γ-radiation increases from 5 to 10 Mrad whereas a higher dose of 15 Mrad lowers it. However, the DCP cured samples show a continuous reduction in their ability to retain modulus. The composite system containing hexa-resorcinol as the bonding agent has better resistance to heat and γ-radiation than the unbonded one.
Native American-Identified Students’ Transition to College: A Theoretical Model of Coping Challenges and Resources
Authors: Rodriguez Adrian A. , Mallinckrodt Brent
Published: September 2018

Interviews with 10 first-year Native American students at a predominately White institution focused on perceptions of risk and protective factors for persistence. Grounded theory analyses suggested a model of mixed resources from two clusters of sources that assist adaptation. Participants generally experienced very high anxiety during the initial 6 to 8 weeks on campus. To cope, they tended to rely initially on established relationships with family and close others off-campus. As participants became more familiar with the university, they formed new connections with faculty, staff, and campus peers. Participants also became more resilient in the face of obstacles through use of internal coping strategies. Through this transition process, participants became involved in various campus support programs or organizations and resolved to further explore their Native American heritage. First-year transition efforts should consider interventions to help Native American-identified students to manage anxiety and form connections on campus very early in their initial semester.
Selective modulation of tonically active GABAA receptor functional subgroups by G-proteins and protein kinase C
Authors: O’Neill Nathanael , Sylantyev Sergiy
Published: September 2018

Ionotropic receptors of γ-aminobutyric acid (GABAARs) produce two forms of inhibitory signaling: phasic inhibition triggered by activation of synaptic GABAARs at GABAergic synapses, and tonic inhibition generated in large part through persistent activation of extrasynaptic GABAARs. It has recently been demonstrated that tonic inhibition may also involve spontaneously opening GABAARs (s-GABAARs) whose activation does not require binding of γ-aminobutyric acid (GABA). Here, we examine intracellular mechanisms modulating GABAARs’ tonic effects in rat dentate gyrus granule cells (DGCs). Cellular control of s-GABAARs-delivered tonic current appears to involve signaling inputs from G-protein-dependent and -independent molecular cascades, whereas tonic GABA-dependent current in DGCs is regulated by protein kinase C. The intracellular agents that modulate s-GABAAR-generated inhibition could thus represent a generic mechanism controlling signal integration in central neural circuits.
Conditions of gas–solid two-phase flow formed in a vertical screw conveyor
Authors: Xiaoxia Sun , Wenjun Meng , Yuan Yuan
Published: September 2018

This study investigates the velocity and pressure distributions of gas flow field in a vertical screw conveyor through EDEM simulation. Results show that the vertical velocity of gas is the highest and that the minimum pressure is negative, which is at the exit, thereby aiding in the upward transportation of particles. The particle state in the vertical screw conveyor is obtained without considering gas (EDEM simulation) and by considering gas (EDEM + FLUENT simulation), respectively. Investigation of the relationship among the screw critical speed, screw diameter, and particle size shows that the conditions of gas–solid two-phase flow form in the vertical screw conveyor. A test is designed to verify the correctness of the conclusions. The results of this study lay a foundation for the development of design methods based on gas–solid two-phase flow in a vertical screw conveyor.