bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbon Nanotubes in Tyre Rubbers. Part 3: Study of the Effect of Nanotubes in Silica-filled Tread Rubbers
Authors: Batrshina R.R. , Mokhnatkin A.M. , Dorozhkin V.P. , Mokhnatkina E.G. , Muradyan V.E. , Mukhtarov A.R.
Published: September 2018

The processing and mechanical properties of green and vulcanised tread rubbers based on styrene butadiene rubber and polybutadiene with the addition of natural rubbers filled with silica and containing single-walled carbon nanotubes (SCNTs) were studied. Two types of rubber were manufactured: one containing untreated SCNTs and stearic acid, ensuring the presence of – COOH groups, and the other with treated SCNTs. The properties of these composites were compared. In both cases, the introduction of SCNTs leads to an increase in the cohesion strength of the green rubber mixes, to an improvement in their vulcanisation properties, and to an increase in their Mooney viscosity. In contrast to tread rubbers filled with carbon black, in the case of filling with silica the Payne effect decreases. The dynamic and other mechanical properties of the vulcanisates change in different ways. The wear resistance, like other service properties, is improved.
Combination of Cyclic Fatigue Testing and Materials Characterisation to Investigate Ageing of Elastomers
Authors: Kroth T. , Lellinger D. , Alig I. , Wallmichrath M.
Published: September 2018

Cyclic fatigue testing and elastomer characterisation were combined to study changes in material properties and network structure of elastomers during thermal ageing. Natural rubber containing a typical additive package with carbon black was studied as a model material. The samples were aged at different temperatures in air or under a nitrogen atmosphere. The fatigue life in number of cycles to failure (S-N curves) was determined from force- and displacement-controlled fatigue tests on tensile bar specimens after different thermal ageing times. Changes in mechanical properties and crosslink density were studied by tensile tests, dynamic mechanical analysis, stress relaxation experiments, compression set measurements, swelling measurements and solid-state NMR. Changes in network density during thermal ageing are related to the interplay between the formation of new crosslinks and chain scission. The average molecular mass of the network chains was found to be a suitable parameter for comparing different characterisation methods. An initial decrease in the molecular mass between two crosslinking points due to post-curing is followed by an increase due to chain scission. A similar trend was found for fatigue life in number of cycles to failure (N) in force-controlled fatigue tests: an increase in N for short ageing times is followed by a decrease after longer ageing times.
The Synthesis and Properties of Novolacs Based on Ternary Mixtures Containing Phenol, Phenolphthalein, and Phthalimidine-containing Bisphenols and of Crosslinked Copolymers Based on them
Authors: Machulenko L.N. , Nechaev A.I. , Donetskaya S.A. , Potopaeva A.A. , Salazkin S.N. , Klemenkova Z.S. , Buzin M.I.
Published: September 2018

By the interaction of formaldehyde with mixtures of phenol, phenolphthalein, and phthalimidine-containing bisphenols in the presence of an acidic catalyst, new co-oligophenol formaldehyde novolacs and crosslinked copolymers based on them are produced. Their properties are studied.
Polypropylene-based Nanostructured Materials
Authors: Kravchenko T.P. , Gorbunova I.Yu. , Filatov S.N. , Kerber M.L. , Rakov E.G. , Kireev V.V.
Published: September 2018

The effect of nanosized carbon additives on the properties and crystallisation of polypropylene was investigated. It was shown that the introduction of carbon nanoparticles affects the crystallisation rate and the properties of polypropylene.
Chlorinated Isoprene Rubbers in Adhesive Composites
Authors: Zuev A.A. , Lyusova L.R. , Boreiko N.P.
Published: September 2018

Now there is not a single area of industry that can do without adhesive elastomer materials. Composites based on synthetic rubbers comprise 75% of the total volume of adhesive materials produced, which is due to the combination of unique properties typical of the elastomer base of the adhesive. The base of many imported adhesives for the bonding of rubber to metal is chlorinated natural rubber. As an alternative, chlorinated synthetic isoprene rubber has been proposed, developed at the Scientific Research Institute for Synthetic Rubber in St Petersburg. The chlorinated isoprene rubber was compared with imported chlorinated natural rubber in adhesive composites, and the physicomechanical properties of mixes based on a blend of chlorinated rubber and nitrile butadiene rubber were investigated. The investigation was conducted on chlorinated natural rubber of grade Pergut S20, chlorinated isoprene rubber SKI-3, and nitrile butadiene rubbers of grades BNKS-28AMN and SKN-26S. The influence of the ratio of chlorinated rubber to nitrile butadiene rubber and the technological factors of mix preparation on the properties of films produced from them was established. It was shown that, in terms of the level of properties, home-produced chlorinated rubber can be used as the base for adhesives for hot bonding of rubber to metal instead of imported Pergut S20.
The Rheological Properties of Composite Materials Based on High-density Polyethylene
Authors: Anpilogova V.S. , Kravchenko T.P. , Nikolaeva N.Yu. , Lin Nei Zo , Osipchik V.S.
Published: September 2018

The rheological properties of nanocomposites based on high-density polyethylene are considered. The advantages of introducing carbon nanotubes and laproxide as modifiers of high-density polyethylene to control their rheological properties are shown.

The promise of composite materials is not in doubt. A considerable number of studies have been devoted to this group of materials. However, many aspects of the practical realisation of the properties of these materials remain inadequately developed [1].
The Structure and Thermal Conductivity of Multicomponent Polymer Composites Filled with Hollow Ceramic and Silicone Microspheres
Authors: Volkov D.P. , Zarichnyak Yu.P. , Marova A.A.
Published: September 2018

The structure of polymer composites has been investigated, and a procedure has been developed for calculating their effective thermal conductivity. Thermal conductivity measurements have been carried out, and the results of calculations have been compared with the authors' own experimental data and with independent experimental data, and also with manufacturers' data which are shown to be hundreds of percent too low.
Optimising the Production of Combined Filter/Sorption Composite Materials
Authors: Genis A.V. , Kuznetsov A.V. , Il'yutkina G.M. , Polyakov L.V.
Published: September 2018

The main relationships governing the production of combined filter/sorption materials by plying-up with the application of adhesive melts have been studied. It has been established that the use of single-stage bonding technology makes it possible to improve the physical and physicomechanical properties of multilayer non-woven mats. The possibility of optimising the plying-up process by using multiple non-linear regression analysis has been demonstrated. Materials with service properties suitable for use in protective clothing have been obtained.
The Influence of the Chemical Composition and Concentration of Components of a Polymer/Nanoparticle Mixture on their Flow Temperature
Authors: Matseevich T.A. , Kovriga O.V. , Askadskii A.A.
Published: September 2018

A scheme has been developed for calculating the flow temperature, Tf, of a system containing a polymer and nanoparticles. The chemical structure of the polymer and nanoparticles, the intermolecular interaction between polymer and nanoparticle when the latter is modified with polar groups, the van der Waals volume and the molecular weight of the polymer, and the concentration and shape of the nanoparticles were taken into account. The dependences of Tf on the radius of the nanoparticles, their concentration, and the number of polar groups grafted to their surface have been established. The calculation scheme has been computerised and is a separate option in the ‘Kaskad’ computer program developed by INEOS.
An Investigation of the Effect of Taurit Filling of Rubber Mixes for the Coating of Radial Lorry Tyre Breakers
Authors: Mindubaev R.R. , Mokhnatkin A.M. , Dorozhkin V.P. , Mokhnatkina E.G.
Published: September 2018

The results of investigating the effect of the shungite analogue Taurit (grade TSD) on the properties (measured on an RPA 2000 instrument) of a breaker rubber mix and of a rubber compound based on synthetic isoprene rubber SKI-3 are set out. Different methods of introducing Taurit have been tested: 10 parts into the rubber at the stage of its production; 10 parts into the standard rubber mix at the first stage of mixing; 10 parts into the rubber subjected to preliminary mechanical plasticisation in a laboratory internal mixer at a temperature of 100°C. The introduction of Taurit into the rubber in small quantities in order to reduce the proportion of rubber constituent in the rubber mix has also been tested. The test results have been compared with results for standard rubber mixes and rubber compounds. When Taurit is introduced into rubber at the stage of its production, the cohesive strength of the rubber mix and the rate of its vulcanisation and also the dynamic modulus components G′ and G″ are increased. When Taurit is introduced into plasticised rubber, again G′ and G″ are increased, there is an increase in plasticity, and the elastic recovery of the rubber mix is reduced. The breaker rubber compound from this mix has the best adhesion to metal cord and the highest dynamic strength. Data on the Payne effect indicate a better carbon black particle distribution when Taurit is introduced into the rubber at the stage of its production. Reduction in the proportion of rubber constituent in the rubber mix leads to a deterioration in the carbon black particle distribution.
The Effect of Pigments on the Flammability Characteristics of a Rubber Compound Based on Methylvinylsiloxane Rubber
Authors: Barbot'ko S.L. , Naumov I.S. , Vol'nyi O.S. , Alifanov E.V.
Published: September 2018

When parts manufactured from polymeric materials are used in different sectors of industry, the use of different colours may be required. The use of pigments of different chemical nature and often possessing catalytic activity may lead to a change in fire hazard characteristics. The effect of several inorganic pigments based on carbon black and metal compounds on the flammability characteristics of a rubber compound of grade VR-42 (white-coloured) based on methylvinylsiloxane rubber has been investigated. A comparison with a standard rubber compound containing magnesium hydroxide has been carried out. The considerable influence of the presence of carbon pigment with nanosized particles on improvement in residual burning (smouldering) time by comparison with the base combination has been shown. No statistically significant change in this characteristic has been established for a coloured rubber compound of grade VR-42 by comparison with the base combination when mineral pigments of different colours and based on metal compounds are introduced.
Investigating the Limiting Mechanical Properties of Nanocomposites Based on High-Density Polyethylene
Authors: Dikanova N.S. , Matseevich A.V. , Kovriga O.V. , Askadskii A.A. , Kravchenko T.P. , Aristov V.M.
Published: September 2018

The effects of nanotubes and modifiers on the elastic modulus and forced elasticity limit of high-density polyethylene were studied. It was found that a very low concentration of multiwalled nanotubes (0.1 wt%) leads to a considerable (twofold) increase in the elastic modulus and a certain increase in the forced elasticity limit. This is connected with the experimentally found increase in the degree of crystallinity of polyethylene when it is filled with the given nanoparticles.
A Comparative Study of the Structure and Properties of Certain Types of Oligodiene
Authors: Shabunina N.A. , Voronchikhin V.D. , Lesik E.I. , Berestyuk A.V. , Karmanova O.V. , Shutilin Yu.F.
Published: September 2018

Using methods of IR spectroscopy (Fourier infrared spectrometer; PerkinElmer) and gel permeation chromatography (Agilent 1200; Agilent Technologies), we studied the microstructure and molecular characteristics of four types of diene oligomer (DO) of different functionality. The dynamic viscosity, η, of DOs was measured on a rotary viscometer (LVDV-II + Pro; Brookfield). A comparative analysis of the obtained results makes it possible to predict the dispersion and the plasticising effect of DOs in polymer–oligomer composites. The temperature dependences of η for different DOs differ in the temperature range 20–60°C; at temperatures of 80°C and above, the values of h are practically identical, i.e. their processing properties are the same, and the replacement of one DO with another will not lead to any need to alter the processing regime of the composites.
The Thermal Processes within Polyethylene in Mixtures with a High Content of Inorganic Components after Plastic Deformation under High Pressure
Authors: Zhorin V.A. , Kiselev M.R.
Published: September 2018

Mixtures of polyethylene and 80% germanium dioxide, magnesium, magnesium oxide, and sodium chloride were subjected to plastic deformation under a pressure of 0.5–4.0 GPa, and were then investigated by differential scanning calorimetry. The enthalpy of melting of the polymer in certain mixtures reached 300 J/g. On thermograms of deformed mixtures, exothermic processes were observed. The observed thermal effects are possibly due to interphase interaction at the phase boundary.
Investigation of the Relaxation Mechanical Properties of Nanocomposites Based on High-Density Polyethylene
Authors: Dikanova N.S. , Matseevich A.V. , Kovriga O.V. , Askadskii A.A. , Kravchenko T.P. , Aristov V.M.
Published: September 2018

The effect of nanotubes and nanofibres on the stress relaxation of nanocomposites based on high-density polyethylene (HDPE) was studied. It was found that a very low concentration of multiwall nanotubes (0.1 wt%) leads to a significant increase in the relaxing stresses over the entire period of relaxation. Generalised curves of the relaxation process were plotted, and it was found that the greatest reinforcing effect is rendered by the multiwall nanotubes with the greatest specific surface.
High-impact Composites of Polypropylene and Nitrile Butadiene Rubber with Improved Compatibility of the Polymer Components, Obtained by Melt Reactive Compounding. Part 1: The Influence of the Nature of the Polar Vinyl Monomer on the Impact Strength and Deformation Strength Properties of the Composites
Authors: Kazakov Yu.M. , Volkov A.M. , Ryzhikova I.G. , Vol'fson S.I.
Published: September 2018

The effect of the components of the modifying system on the impact strength and deformation strength characteristics of polypropylene/nitrile butadiene rubber (NBR) composites obtained by reactive compounding was investigated. Studies were conducted on composites containing 23 wt% BNKS-18AMN nitrile butadiene rubber and peroxide modifying system coagents – polar vinyl monomers: maleic anhydride (MA), its polyester with monoethylene glycol (MEG), and a complex of MEG with aromatic amine antioxidant Diaphene FP (DFP). At the same time, we introduced presynthesised compatibilisers based on blends of polypropylene with elastomers of different polarity: ternary ethylene propylene diene copolymer (EPDM) and an NBR modified by grafting of MA or MEG + DFP. It was established that, in this series of coagents, the MEG + DFP complex ensures the most effective dispersion of the BNKS-18AMN phase in the polypropylene matrix during reactive compounding of composites and, in accordance with this, leads to a significant increase in their impact strength and elongation at break. Here, the greatest specificity and effectiveness are possessed by compatibilisers into which an elastomer phase has been introduced: blends of polypropylene with non-polar EPDM, modified with MA, or blends with polar BNKS-18AMN, modified with an MEG + DFP complex.
The Filling of Polyether Ether Ketones as a Way of Producing Composites with High Service Properties
Authors: Mikitaev A.K. , Salamov A.Kh. , Beev A.A. , Beeva D.A.
Published: September 2018

Aromatic polyether ether ketones are polymers whose volume of production is now increasing at a rapid rate, which is due to the important array of service properties of these polymers. Certain processing characteristics of composites based on polyether ether ketones are considered in this paper.
An Investigation of the Effect of Laser Radiation on the Dielectric Parameters of Polymethyl Methacrylate
Authors: Torshkhoeva Z.S. , Akhriev A.S. , Kunizhev B.I.
Published: September 2018

The effect of laser radiation on the dielectric parameters of polymethyl methacrylate at a frequency of 50 kHz in the 170–420 K temperature range was investigated. It was shown that the laser pulse treatment of specimens leads to considerable changes in their dielectric permittivity and dielectric loss tangent.
A Study of the Laws Governing the Modification of Polyimide Materials used in Multilayer Structures of Space Vehicles
Authors: Kramarev D.V. , Osipchik V.S. , Chalaya N.M. , Berezina A.B. , Kolesnikov A.V.
Published: September 2018

The effect of modifying additives on the kinetics of imidisation of polyamido acid and the physicomechanical properties of the obtained materials was investigated. The optimum parameters for the moulding of polyimide films were established.
Polymer Fireproofing Agents for Lowering the Flammability of Cellulose Materials
Authors: Akhrarov B.B. , Allamuratov M.U. , Mukhamedgaliev B.A.
Published: September 2018

Certain questions concerning the development of new polymer fireproofing agents for cellulose materials are considered. The mechanisms of the fireproofing characteristics of the new polymers are clarified.
An Investigation of the Mechanical Properties of Nanocomposites Based on Polyepoxy Isocyanurates and Monodispersed Carbon Nanoparticles
Authors: Galitseiskii K.B. , Petunova M.D. , Afanas'ev E.S. , Starozhitskii M.V. , Kovriga O.V. , Askadskii A.A.
Published: September 2018

Nanocomposites based on polyepoxy isocyanurate crosslinked systems of different chemical composition were produced in order to investigate the specific effect of technical nanocarbon on each individual polymer network. Monodispersed carbon particles were produced by methane chlorination conducted in a continuous reactor in a non-equilibrium regime with a chlorine deficit. The dependences of the forced elasticity limit, stress relaxation, etc., on the degree of filling were analysed. The possibility of interphase interaction between a specific polyepoxy isocyanurate network and ‘nanofiller’ was investigated. It was shown that a fairly low concentration (1 wt%) of monodispersed carbon particles of 20–25 nm size leads to a 25–30% increase in the elastic modulus and forced elasticity limit; similarly, the relaxation characteristics are also increased. It was established that improvement in a number of such properties is connected with the greater influence of interphase interactions between the polymer and filler on account of the large surface layer area.
The Effect of Dissipation on the Moulding of Composite Articles in Closed Moulds
Authors: Baranov A. V. , Yunitskii S.A.
Published: September 2018

The flow and heat exchange in the process of impregnation of filler by non-Newtonian fluid during the moulding of composite articles in closed moulds are investigated. Flow is described by the modified Brinkman equation. From the rheological point of view, the medium comprises a power-law fluid. In writing the energy equation, a single-temperature model is used. Dissipative heat generation is taken into account. The problem is solved by the numerical finite difference method. The effect of dissipation (the Brinkman number) on the distribution of the mass-average temperature over the length of the cavity with different Péclet numbers is shown.
The Internet as a Context: Exploring Its Impacts on National Identity in 36 Countries
Authors: Lu Jia , Yu Xin
Published: September 2018

The rise of the Internet brings up a debate about its role in eroding or strengthening national identity. Taking the perspective of media ecology, this article saw the Internet as a context and explored its impacts on social context in which national identity is constructed. Using the data from the World Values Survey (2010–2014), this article carried out multilevel analyses with 50,240 respondents in 36 countries. The results illustrate how online distribution of information, power, and freedom affects cognition, affection, and action of national identity. National identity is eroded by information distribution but is strengthened by power distribution. Power distribution and freedom distribution work together to neutralize and regulate the effects of information distribution.
Cost-effectiveness of colorectal cancer screening programmes using sigmoidoscopy and immunochemical faecal occult blood test
Authors: Senore Carlo , Hassan Cesare , Regge Daniele , Pagano Eva , Iussich Gabriella , Correale Loredana , Segnan Nereo
Published: September 2018

Objective

Several European countries are implementing organized colorectal cancer (CRC) screening programmes using faecal immunochemical test (FIT) and/or flexible sigmoidoscopy (FS), but the cost-effectiveness of these programmes is not yet available. We aimed to assess cost-effectiveness, based on data from the established Piedmont screening programme.

Methods

Using the Piedmont programme data, a Markov model was constructed comparing three strategies in a simulated cohort of 100,000 subjects: single FS, biennial FIT, or sequential strategy (FS + FIT offered to FS non-responders). Estimates for CRC incidence and mortality prevention were derived from studies of organized screening. Cost analysis for FS and FIT was based on data from organized programmes. Incremental cost-effectiveness ratios (ICER) between the different strategies were calculated. Sensitivity and probabilistic analyses were performed.

Results

Direct costs for FS, and for FIT at first and subsequent rounds, were estimated as €160, €33, and €21, respectively. All the simulated strategies were effective (10–17% CRC incidence reduction) and cost-effective vs. no screening (ICER <€1000 per life-year saved). FS and FS + FIT were the only cost-saving strategies, with FS least expensive (€15 saving per person invited). FS + FIT and FS were the only non-dominated strategies. FS + FIT were more effective and cost-effective than FS (ICER €1217 per life-year saved). The residual marginal uncertainty was mainly related to parameters inherent to FIT effectiveness and adherence.

Conclusions

Organized CRC screening programmes are highly cost-effective, irrespective of the test selected. A sequential approach with FS and FIT appears the most cost-effective option. A single FS is the least expensive, but convenient, approach.
Borderline Personality Features Mediate the Association Between ADHD, ODD, and Relational and Physical Aggression in Girls
Authors: Babinski Dara E. , McQuade Julia D.
Published: September 2018

Objective: This study investigates borderline personality features (BPF) as a mediator of the association between ADHD and ODD symptoms and aggression in girls. Method: Parents of 118 girls ( Mage = 11.40 years old) with and without ADHD completed ratings of ADHD and ODD severity, and parents and youth provided ratings of physical and relational aggression. Results: ADHD, ODD, and their subfactors were significantly correlated with BPF, and these variables were associated with aggression measures. BPF fully mediated the association between total ODD symptom severity and relational and physical aggression by parent and youth report. At the subfactor level, BPF fully mediated the association between hyperactivity/impulsivity and oppositional behavior and physical and relational aggression. Conclusion: These findings add to a growing literature showing the relevance of BPF as a risk factor for poor social functioning in youth and point to the importance of continued work examining BPF among girls with ADHD and ODD.
Active controller design for precision computerized numerical control machine tool systems
Authors: Fu Cheng-Biao , Tian An-Hong , Li Yu-Chung , Yau Her-Terng
Published: September 2018

The control of a tri-axis computerized numerical control machine tool platform, which is driven by an AC servo motor is discussed in this paper. To establish a system model, the particle swarm optimization algorithm was used to transform the X–Y platform of a machine tool into a transfer function before simulation and verification of digital control was done using MATLAB. The control methods used in this study include proportional-integral-derivative control, quantitative feedback design theory and sliding mode control. They were realized with C# and the errors of motion trajectories generated by the controllers were observed. It was concluded that of the three methods studied, sliding mode control produced the lowest error rate.
A social safety net? Rejection sensitivity and political opinion sharing among young people in social media
Authors: Bäck Emma A , Bäck Hanna , Fredén Annika , Gustafsson Nils
Published: September 2018

One reason why people avoid using social media to express their opinions is to avert social sanctions as proposed by the spiral of silence theory. We here elaborate on individual-level sensitivity to social rejection in relation to voicing political opinions on social media sites. Given the uncertainty about sharing political views in social media, and the fact that social acceptance, or rejection, can be easily communicated through, for instance, likes, or a lack of likes, we argue that rejection sensitive individuals are less likely to share political information in social media. Combining an analysis of unique survey data on psychological characteristics and online political activity with focus group interviews with Swedish youth supports our argument, showing that rejection sensitive individuals are less inclined to engage politically in social media. The results extend on previous research by establishing the role of rejection sensitivity in political engagement in social media.
Development and validation of Cognitive Training Intervention for Alzheimer’s disease (CTI-AD): A picture-based interventional program
Authors: Bajpai Swati , Tripathi Manjari , Pandey RM , Dey A.B , Nehra Ashima
Published: September 2018

Introduction

Alzheimer’s disease is a gradual and progressive disorder which cripples the person’s functionality due to cognitive decline. Many clinicopathological and pharmacological therapy has the potential to slow down the progression of the disease but has limited efficacy. One complimentary approach that has emerged is cognitive training interventions which have shown synergistic effect with the drug therapy. Nevertheless, many cognitive interventions lack on specificities of the intervention due to which its efficacy gets scrutinized.

Objective

To describe the foundation, content, and development of Cognitive Training Intervention for Alzheimer’s disease (CTI-AD) along with the treatment feasibility based on a pilot study.

Materials and methods

A culture-specific picture-based eight weeks cognitive training manual was developed based on extensive review and focused group discussions. It was standardized on 63 older participants (48 healthy controls (HC); 15 early Alzheimer’s disease cases).

Results

All the tasks were progressive in nature and were found effective in discriminating the cognitive performance of early Alzheimer’s disease and HC throughout the intervention period. Moreover, it also improved early Alzheimer’s disease performance on the memory (HC: 1st week/8th week = 21.6 ± 5.7/57.3 ± 19.0; early Alzheimer’s disease: 1st week/8th week = 48.5 ± 22.9/60.5 ± 21.8); attention (HC: 1st week/8th week = 90.2 ± 18.0/196.9 ± 28.0; early Alzheimer’s disease: 1st week/8th week = 216.6 ± 78.2/286.8 ± 87.0) and language (HC: 1st week/8th week = 29.8 ± 9.4/115.3 ± 31.1; early Alzheimer’s disease: 1st week/8th week = 211.8 ± 68.4/270.4 ± 104.9) domains, respectively, from the baseline level.

Conclusion

The current manual (CTI-AD) is one of the first promising non-pharmacological program developed nationally with a strong theoretical base to cater to the tertiary needs of the older adults with early Alzheimer’s disease.
Times Have Changed: Using a Pictorial Smartphone App to Collect Time–Use Data in Rural Zambia
Authors: Daum Thomas , Buchwald Hannes , Gerlicher Ansgar , Birner Regina
Published: September 2018

One challenge of collecting socioeconomic data, such as data on time-use, is recall biases. While time-use researchers have continuously developed new methods to make data collection more accurate and easy, these methods are difficult to use in developing countries, where study participants may have low literacy levels and no clock-based concepts of time. To contribute to the closing of this research gap, we developed a picture-based smartphone app called Time-Tracker that allows data recording in real time to avoid recall biases. We pilot tested the app in rural Zambia, collecting 2,790 data days. In this article, we compare the data recorded with the app to data collected with 24-hours recall questions. The results confirm the literature on recall biases, suggesting that using the app leads to valid results. We conclude that smartphone apps using visual tools provide new opportunities for researchers collecting socioeconomic data in developing countries.
Portraits of Ganas: The College-Going Pathways of Undocumented Students at a Texas HBCU
Authors: Allen Taryn Ozuna , Zhang Yi (Leaf) , Romo Enrique
Published: September 2018

The process of pursuing a higher education degree can be particularly complicated for undocumented students as they navigate the K-16 pipeline. Ganas, or the desire to succeed, is a cultural value that can serve a motivation to overcome educational obstacles. Using portraiture, this article highlights the ways students demonstrated ganas in the ways they prioritized relationships, honored parental sacrifices, and demonstrated resilience. Recommendations for research and practice are offered.
Investing Time for Your In-Game Boyfriends and BFFs: Time as Commodity and the Simulation of Emotional Labor in Mystic Messenger
Authors: Ganzon Sarah Christina
Published: September 2018

Mystic Messenger is a real-time mobile dating simulator and otome game that simulates how people fall in love online. In this essay, I will look at significant parallels between casual games and otome games and point out the ways in which both define women as players and consumers of games. By focusing on Mystic Messenger, I examine the ways in which the game’s real-time simulation of emotional labor becomes a way of policing women’s desires, a way of reinforcing nurturing roles over women’s desires, and a way of literally commodifying the assumedly female player’s leisure time. Furthermore, I also examine player practices and discussions of cheating within the player community, tagging these as light forms of resistances and ways in which various individuals in the community assert their identity and their agency over their own time.
Assessment Through the Short Physical Performance Battery of the Functionality in Individuals With Metabolic Syndrome Exposed to Whole-Body Vibration Exercises
Authors: Paineiras-Domingos Laisa Liane , da Cunha Sá-Caputo Danúbia , Reis A.S. , Francisca Santos A. , Sousa-Gonçalves Cíntia Renata , dos Anjos Elzi Martins , dos Santos Pereira Mario José , Sartorio Alessandro , Bernardo-Filho Mario
Published: September 2018

Physical activity is recommended in the management of individuals with metabolic syndrome (MetS), and recent studies have suggested whole-body vibration exercise (WBVe) for this population. The aim of this study was to evaluate the functionality through the Short Physical Performance Battery (SPPB) in individuals with MetS after WBVe. The SPPB evaluates the balance, the gait speed, and the lower limb strength (five-chair stand [5CS] test). Forty-four individuals with MetS were divided into WBVe (WBVeG) and control (CG) groups. The individuals of the WBVeG performed 10 sessions of WBVe in an oscillating/vibratory platform (OVP), barefoot, for 3 minutes at the peak-to-peak displacements of 2.5, 5.0, and 7.5 mm, with a resting period of 1 minute (total time: 18 minutes/session). The frequencies ranged from 5 up to 14 Hz. The individuals of the CG performed all the steps of the study, but the OVP was turned off. Before the first and after the tenth session, the individuals performed the SPPB. Significant responses were found in the WBVeG, analyzing the total score of the SPPB ( P = .005), the balance test ( P = .01), the gait speed ( P = .006), and the 5CS test ( P = .03), resulting in the improvement of the functionality of individuals with MetS.
An efficient pricing algorithm for American options with double stochastic volatilities and double jumps
Authors: Zhang Sumei
Published: September 2018

The purpose of the paper is to provide an efficient pricing algorithm for American options with stochastic volatilities and jumps. This paper extends the double Heston model with double exponential jumps and derives the characteristic function of the model by Feynman–Kac theorem. With the obtained characteristic function, this paper also extends the Fourier-cosine expansion method for pricing Bermudan options to the model. Based on the COS method, this paper approximates American options by using Richardson extrapolation schemes on a series of Bermudan options and provides a pricing algorithm for American put options. Numerical results show that the proposed pricing algorithm is efficient, especially for short-term American put options.
Conceptualising a policy framework for the implementation of medical marijuana in the Caribbean territory of Barbados
Authors: Griffith Alana DD , Cohall Damian H
Published: September 2018

Unlike the recent global trend of a decline in the prohibition of the use of Cannabis sativa for recreational and medical uses, Barbados and other small island states in the Caribbean have maintained their prohibitive legislation and policies on the use of the herb. A negative social construct of the use of cannabis and its effects in the consciousness of many in the Caribbean have contributed to the maintenance of the prohibitive policies towards the use of the herb. This article highlights the negative societal construct of the herb and its impact on the youth as two critical factors limiting the implementation of medical marijuana laws. It conceptualises a possible policy framework that would address this issue by enabling a phased implementation of the use of medicinal products from marijuana in the management of selected conditions from an evidence-based vantage point. Barbados would need to evaluate the mechanisms under current prohibitive legislation and create amendments to allow for an incremental approach on the use of the plant or products thereof for medicinal purposes in light of societal concerns. The policy framework should result in discreet enforceable mechanisms to facilitate and monitor the importation and development of efficacious and safe medicinal products for prescribing to authorised patients throughout the island’s healthcare system.
Caudal mandibular fracture repair using three-dimensional printing, presurgical plate contouring and a preformed template to aid anatomical fracture reduction
Authors: Southerden Peter , Barnes Duncan M
Published: September 2018

Case summary

Two cats were presented with mandibular fractures following head trauma. Following a CT scan, both were diagnosed with fractures of the ramus. The CT scans were used to print three-dimensional (3D) models of the mandibular fractures, which were used to pre-contour stainless steel mini-plates. These were fixed to the models and the screw positions used to produce a stainless steel template. The template was used as a pattern during surgery to drill holes in the ramus so that the pre-contoured mini-plates could be fixed in the exact same position as they had been on the 3D model. The fractures healed in both cats achieving normal jaw function and occlusion.

Relevance and novel information

Conventional techniques used to treat caudal mandibular fractures in cats, such as maxillomandibular fixation and bignathic encircling and retaining device (BEARD), are associated with significant patient morbidity and postoperative complications. Internal rigid fixation is difficult because of small bone size, requirement for considerable plate contouring and difficulty in achieving accurate anatomical reduction of caudal mandibular fractures. These are the first reported cases of mini-plate fixation of caudal mandibular fractures in cats using 3D models, pre-contouring of bone plates and the use of a template to facilitate accurate plate positioning, which may provide an alternative technique suitable for fixing caudal mandibular fractures in cats.
Gay Acquaintanceship and Attitudes toward Homosexuality: A Conservative Test
Authors: DellaPosta Daniel
Published: September 2018

Does acquaintanceship with gays and lesbians produce more accepting attitudes toward homosexuality and gay rights? Although most scholars and laypeople would likely answer in the affirmative, previous work has struggled to answer this question because of the difficulty in disentangling social influence from social selection. Using panel data from the 2006 to 2010 editions of the General Social Survey, this study provides a conservative test of the contact hypothesis for gay acceptance. People who had at least one gay or lesbian acquaintance at baseline exhibited larger attitude changes at two- and four-year follow-ups with regard to support for same-sex marriage and moral acceptance of homosexuality. Furthermore, this contact effect extended even, and perhaps especially, to people who otherwise displayed more negative prior attitudes and lower propensities for gay and lesbian acquaintanceship.
Standing Tall on Their Shoulders: Essential Eponyms in Shoulder Surgery
Authors: Villacis Diego C , Popkin Charles A , Nowell Jared A , Qayyum Usama , Brabston Eugene W , Jobin Charles M , Ahmad Christopher S , Levine William N
Published: September 2018

There has been enormous advancement in the field of shoulder surgery since its initial establishment as a subspecialty. This is due in large part to the numerous contributions made by clinicians who came before us. This review of eponyms in shoulder surgery provides the opportunity to honor our predecessors and their contributions as well as promote the correct use of eponyms going forward.
O texto autobiográfico em sala de aula do ensino fundamental
Authors: Rocha Flávia Cavalcante , Zavam Aurea Suely
Published: September 2018

Com este trabalho, objetivamos contribuir com o ensino e a aprendizagem da produção escrita por meio da produção de textos autobiográficos por alunos do 9º ano do Ensino Fundamental de uma escola pública de Fortaleza-CE. Concebemos uma sequência didática, baseada na proposta de Dolz, Noverraz e Schneuwly (2004), como recurso metodológico para verificar o desempenho dos alunos nos textos escritos assim como para comprovar a eficiência de tal procedimento como proposta de ensino. Desse modo, para desenvolver a competência dos alunos na produção de textos, sobretudo os escritos, seguimos, ainda, as orientações dos Parâmetros Curriculares Nacionais de Língua Portuguesa, e mais recentemente da Base Nacional Comum Curricular, que norteiam o trabalho com gêneros textuais em sala de aula e certificam que é necessário contemplar a diversidade de textos e gêneros, não apenas por sua relevância social, mas também porque textos pertencentes a diferentes gêneros são organizados de diferentes formas. Apresentamos, então, atividades direcionadas para o trabalho com o gênero autobiografia em sala de aula. Nessa perspectiva, trabalhamos a produção escrita, intencionando valorizar a identidade dos alunos e ressaltar a sua importância como indivíduos participativos e críticos na sociedade onde vivem. Em síntese, este trabalho se propõe a investir na melhoria das práticas de leitura e escrita e pode ser constituído como uma iniciativa pedagógica de aplicação do Modelo Ideológico de Letramento preconizado por Street (2014).
The Fabrication of Freestanding Heterogeneous Copper-Tin Films with Meniscus Brush Plating Electrodeposition
Authors: Scott Kimberly Y. , Halajko Anna , Amatucci Glenn G.
Published: September 2018

A meniscus brush plating electrodeposition technique was utilized in conjunction with a post deposition heat treatment to formulate freestanding copper-tin alloy films for negative electrodes of lithium-ion batteries. The described fabrication technique intertwined the electrode and current collector for improved cell volume utilization and stability. Two designs were examined to establish the best diffusivity to form electrochemically proficient copper-tin alloys. Fabrication was optimized to promote diffusion of copper and tin and to form the desired intermetallic phase of Cu6Sn5. This improved design fabricated films with competitive areal capacities above 1000 mAh/cc and 2.5 mAh/cm2 for the complete electrode and current collector structure.
Investigation of The Electrode Pathway of Quinoline Azo Dye Compound via Convolutive Voltammetry and Digital Simulation
Authors: Al-Owais A. , El-Hallag I. S.
Published: September 2018

The electrochemical behavior and the electrode reaction of quinolone azo dye compound was investigated using convolutive cyclic voltammetry at mercury electrode in 50% (v/v) ethanolic Britton-Robinson solutions of pH 2.5 – 12.0. Four electrons slow reduction wave was consumed in acidic and alkaline solutions corresponding to the reduction of the more easily N = N center. A second more cathodic irreversible , pH – dependent, 2-electron wave represents the reduction of quinolone ring. Cyclic voltammetry and convolution transforms were used to determine the kinetic parameters of the electroactive species.The extracted electrochemical parameters were confirmed via digital simulation.Controlled potential coulometry technique was used for calculation the overall number of electrons involved in electrode reaction.
ZnO Nanoflakes on Pb Plates with Antibacterial Effects by Electrochemical and Hydrothermal Deposition
Authors: Shyu Yow-Chyun , Chieh Tsai Shin , Su Wei Min , Lu Chien-Cheng , Weng Cheng-Yuan , Shan Lee Yu , Hao Hong Chen , Lin Jing-Jenn , Lin Chia Feng , Yu Chang-Tze Ricky , Chen Yi Cian , Yu Tzu-Yi , Chen Hsian
Published: September 2018

ZnO nanoflakes were grown on the lead (Pb) plates using the electro- hydrothermal deposition methods. To investigate the influence of electrodeposition current, the ZnO seed layer was electrodeposited on the lead plates at a larger current of 160 mA (current density of 40 mA/cm2) and a smaller current of 12 mA (current density of 3mA/cm2), respectively. Then, ZnO nanoflakes were grown on top of the seed layer. Multiple analyses including field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), photoluminescence (PL) were performed on the ZnO nanostructures/Pb plates. Furthermore, surface con-tact angle measurements were conducted to study the hydrophobic properties and OD 600 antibacterial tests were used to investigate the antiseptic effects. Results indicate that the ZnO nanoflakes with the seed layer grown at a lower current of 12 mA exhibited good hydrop-hobic properties and strong antibacterial effects. ZnO nanoflakes/Pb plates show promising for future anti-radiation, antibacterial, and waterproof lead clothing applications.
Trace Determination of Lead and Cadmium using Graphene/[Ru(NH3)6]3+/Nafion Modi-fied Glassy Carbon Electrodes
Authors: Palisoc Shirley , Natividad Michelle , Mae Calde Diana Mae , Rosopa Elias Rafael
Published: September 2018

Graphene/[Ru(NH3)6]3+/nafion modified glassy carbon electrodes were fabricated using the drop coating technique. The fab-ricated electrodes were characterized using scanning electron microscopy (SEM) and cyclic voltammetry (CV). Simultaneous detection of lead (Pb2+) and cadmium (Cd2+) was done via anodic stripping voltammetry (ASV). The effects of varying the amounts of graphene and [Ru(NH3)6]3+ on the transport and sensing properties of the modified electrodes were determined. SEM results showed that the deposited films were smooth and uniform. CV results showed that the peak currents increase monotonically with the amounts of graphene and [Ru(NH3)6]3+. ASV results showed that modification of the GCE with graphene, [Ru(NH3)6]3+ and Nafion greatly enhanced the electrode’s sensitivity in detecting Pb2+ and Cd2+. This can be attributed to the high surface area-to-volume ratio of graphene, the mediation of elec-tron transfer by [Ru(NH3)6]3+ and the antifouling and cationic exchange capabilities of Nafion. The highest peak current for both Pb2+ and Cd2+ were obtained from the electrode modified with 1.5 mg [Ru(NH3)6]3+ and 3.0 mg graphene. A linear relationship between the peak current and metal concentration was obtained in the range of 1.4 ppb to 20 ppb for both Pb2+ and Cd2+ with a detection limit of 1.4 ppb. The modified electrodes were successful in detecting Cd2+ in real water samples. ASV results were verified using atomic absorption spec-troscopy.
Preparation of CuPc/RGO Nanocomposites and Their Electrocatalytic Behaviors for Oxygen Reduction Reaction
Authors: Zuo Guofang , Wang Peng , Li Zhifeng , Yang Jiandong
Published: September 2018

In this paper, copper phthalocyanine/reduced graphene oxide (CuPc/RGO) nanocomposites were synthesized by aromatic π-π stacking interaction and well characterized by scanning electron microscopy (SEM) and fluorescence spectrometry. The composites were modified on the surface of glass carbon electrode (GCE) and their electrochemical behaviors of CuPc/RGO for electrocatalytic oxygen reduction reaction (ORR) were studied by cyclic voltammetry (CV). The study showed when the mass ratio of RGO to CuPc in composite achieved 1:1, the composite film performed excellent electrocatalytic activity towards the ORR.
Manganese(III) Porphyrin as Electrocatalyst for Hydrogen Evolution Reaction
Authors: Alenezi Khalaf
Published: September 2018

5,10,15,20-tetraphenyl-21H,23H-porphine manganese(III) chloride (Mn(TPP)Cl) has been evaluated as electrocatalyst for Hydrogen Evolution Reaction (HER) in the presence of triethylamine hydrochloride (Et3NHCl) as source of proton. The direct reduction of Et3NHCl on vitreous carbon electrode occurs at Ep -1.6 V vs Ag/AgCl in [Bu4N][BF4]-CH3CN. Interestingly, in the presence of Mn(TPP)Cl as electrocatalyst the reduction potential shifts to -1.20 V. Based on gas chromatography analysis, the formation of H2 gas, with a current efficiency of ca. 58% after 2 h, is observed with a yield of 8 μmoles and a turnover of 2.5. However, the chemical yield at carbon electrode was about 35%. These results reflect the exquisite electrocatalytic efficiency of Mn(TPP)Cl in Hydrogen Evolution Reaction (HER).