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Serious Game for Children with Autism to Learn Vocabulary: An Experimental Evaluation
No full textThe use of serious games (SGs) to provide intervention for various skills to children with autism spectrum disorder (ASD) has increased in the recent years. However, the potential of these games has not been utilized to provide learning of vocabulary to children with ASD. In designing games for children with ASD, there is a need to consider components specifically from the perspectives of ASD and the generic components that can support from the theoretical, content, and game design aspects. In the absence of any existing framework to design games for children with ASD, this article first introduces a framework named serious game design framework (SGDF), constructed to provide support throughout the design process. This framework was constructed based on the extensive review of the literature on ASD and existing SGDFs. The article then focuses on the design and development of a SG prototype based on SGDF. An experimental evaluation prototype was conducted to examine the effectiveness using the withdrawal design of single-subject research design (SSRD) in improving the receptive identification of vocabulary items among children with autism before and after using the prototype. The receptive identification of vocabulary items is measured in terms of the number of correct responses given and the number of attempts made to identify the correct response. The pre- and post-evaluations of the SG prototype show that learning of vocabulary items among children with ASD improved after using the game and they retained items at the end of weeks 1 and 2 following the withdrawal of intervention
Identification of novel chemical structures of sulfo-imidazolium zwitterionic-type salt basis on 2D NMR analysis
No full textThe reaction of the equimolar mixture of imidazole and 1,4-butanesultone was performed at 90 °C in ethylbenzene for 12 h and the zwitterionic and ionic structures of the product investigated by the NMR analysis. The present work displayed the great importance of 2D NMR analysis on the structure elucidation of this sulfonic acid functionalized liquid salt. The results of NMR analysis demonstrate that 4-imidazole-1-yl-butane-1-sulfonic acid did not exist and really a mixture of zwitterionic and ionic compounds is produced
Multiple resistive switching behaviours of CH3NH3PbI3 perovskite film with different metal electrodes
No full textThe utilization of defects in organic-inorganic hybrid perovskite materials such as CH3NH3PbI3 is beneficial for memory applications. In this work, a simple CH3NH3PbI3 memory device with various commonly used electrodes such as aluminium (Al), silver (Ag), and gold (Au) yielded different switching behaviours. Using Al in ITO/CH3NH3PbI3/Al device reveals Resistive Random Access Memory (ReRAM) behaviour with a SET voltage of 4.5 V and can be RESET by applying a negative sweep voltage above 1.3 V due to the formation of iodide vacancy filament. Interestingly, by using Ag and Au cathodes to replace Al, yielded Write-Once-Read-Many (WORM) resistive switching characteristics. The conversion process from OFF to ON occur at around 4.7 V and 4.0 V for Ag and Au, respectively. The “shorting effect” remains even though a reverse voltage was applied indicating data retention. These fabricated devices could contribute to further understanding of selecting the right electrodes and open up new possibility of studies in the direction of resistive switching memory applications
Synthesis and fluorescence studies of selected N-aryl-2-aminoquinolines: Effect of hydrogen bonding, substituents and ESIPT on their fluorescence quantum yields
No full textN-aryl-2-aminoquinolines have been widely synthesised and used in biological applications. However, their luminescence properties have not been studied in detail. Herein a series of N-aryl-2-aminoquinolines was synthesised from substitution reaction between 2-chloroquinoline and anilines with different substituent groups gave sufficient yield from 72–90%. The fluorescence behaviour was investigated in toluene, ethyl acetate and ethanol. The result shows that fluorescence quantum yield of N-aryl-2-aminoquinolines was the highest in toluene, followed by in ethyl acetate and the lowest in ethanol. Quenched emission observed in ethanol is caused by site-specific fluorophore-solvent hydrogen bonding interactions, inducing deactivation of the quinolinyl ring system. The bell-shaped Hammett plot of various substituted compounds suggested that both strong electron donating and electron withdrawing groups caused significant quenching in the fluorescence quantum yields. Therefore, most types of substituent groups on the phenyl moiety, hydrogen bonding between the fluorophore and solvent, and excited-state intramolecular proton transfer (ESIPT) were found as crucial contributors to fluorescence quenching of N-aryl-2-aminoquinolines
Synergistic inhibition of melanoma xenografts by Brequinar sodium and Doxorubicin
No full textMalignant melanoma continues to be a fatal disease for which novel and long-term curative breakthroughs are desired. One such innovative idea would be to assess combination therapeutic treatments – by way of combining two potentially effective and very different therapy. Previously, we have shown that DHODH inhibitors, A771726 and Brequinar sodium (BQR) induced cell growth impairment in melanoma cells. Similar results were seen with DHODH RNA interference (shRNA). In the present study, we showed that combination of BQR with doxorubicin resulted in synergistic and additive cell growth inhibition in these cells. In addition, in vivo studies with this combination of drugs demonstrated an almost 90% tumor regression in nude mice bearing melanoma tumors. Cell cycle regulatory proteins, cyclin B1 and its binding partner pcdc-2 and p21 were significantly downregulated and upregulated respectively following the combined treatment. Given that we have observed synergistic effects with BQR and doxorubicin, both in vitro and in vivo, these drugs potentially represent a new combination in the targeted therapy of melanoma
A novel damage index for online monitoring of RC slabs under monotonic loading by integration of process controlling into acoustic emission technique
No full textThis study introduces a novel structural health monitoring scheme for cementitious composite slabs with the aid of acoustic emission (AE) technique coupled with statistical process controlling (SPC) method. The adopted framework is an integrated monitoring solution that effectively relates current state (damaged) to reference state of the structure. Evaluation of the latter was made possible using autoregressive model incorporating a set of damage-sensitive feature. In order to provide a benchmark damage indicator, the collected data were processed using control chart analysis. The damage indicators for the former was similarly obtained and then compared with the benchmark to gauge the structural damage. These control charts offer a robust framework meticulously identifying inconsistency in the damage-sensitive feature imposed over the monitoring period. Linear and quadratic projections were also incorporated into SPC model to enhance identification of system transition to other damage states
Manipulating of nanometer spacing dual-wavelength by controlling the apodized grating depth in microring resonators
No full textWe propose a passive photonic design for an optically pumped laser system and tunable dual-wavelength generation application by employing optical nonlinear mode coupling of two coupled III–V semiconductor microring resonators, which is connected to a pump and drop waveguide buses. One of the two rings contains a grating, whereas the other has a planar surface. The mechanism underlying the dual-wavelength generation can be explained via the resonance detuning of the spectra that results in nonlinear mode mixing. The tunability of the wavelengths can be achieved by altering the grating depth of the microring resonator and the power coupling coefficients. In the grating design of the microring resonators, we have selected a trapezoidal-profiled apodized grating to obtain low reflectivity at the sidelobes. A time-domain traveling wave (TDTW) analysis yields an InGaAsP core refractive index of 3.3. This core is surrounded by a grating InP cladding with a refractive index of 3.2. We further confirm that the propagation of a Gaussian pulse input with a power of 10 mW and a bandwidth of 0.76 ps is well confined within the system mode propagation. The results show a 2:1 fan-out of two spectrally separate signals, which can be employed for compact and high functional sources on chips
Alpha-cluster preformation probability in even-even actinide nuclei
No full textThe preformation probability of alpha cluster in the even-even actinide nuclei was determined using the cluster-formation model. The actinides chosen were with high and low intensity of alpha-decay mode. The results showed well production of preformation probability, which had consistence with other even-even heavy alpha-decay nuclei. Actinides have alpha cluster preformation before the emission as the heavy nuclei. The behavior of the preformation probability indicated new submagic shell at N = 142 and 146 and clearly confirmed those of N = 126 and 152
Mode-locked thulium doped fiber laser with zinc oxide saturable absorber for 2 μm operation
No full textIn this work, a 2.0-µm mode-locked thulium doped fiber laser is demonstrated using zinc oxide (ZnO) as the saturable absorber (SA) in a thulium doped fiber laser (TDFL). The ZnO nanorods was prepared by the facile hydrothermal method, and then embedded in polyethylene oxide composite film to form the SA. The laser is capable of generating soliton pulses at a central wavelength of 1945.45 nm with a 3-dB bandwidth of 3.47 nm. The pulse width is measured to be 1.395 ps, only slightly higher than the calculated transform-limited pulse width of 1.15 ps. The peak power of the generated mode-locked pulses is then calculated to be as high as 41.88 W, with a signal-to-noise ratio of 50.5 dB. The fabricated ZnO film in this work would allow the generation of mode-locked pulses, which could be useful for applications in spectroscopy and medicine due to the eye-safe and highly sensitive nature of the 2.0-µm region
Determination of Flow Patterns in Vertical Upward Two-Phase Flow Channel via Void Fraction Profile
No full textTwo-phase flow happens widely in the industrial plants and certain equipment. This paper attempts to study the characteristics of two-phase flow in a vertical piping system. This was achieved by comparing the void fraction, in the working fluid, by employing Constant Electric Current Method (CECM) with the actual observation using high-speed camera. The experiment requires a complete set of two-phase flow system information and was conducted based on various flow conditions. In order to carry out this experiment, the two-phase flow loop was constructed using a specific experimental apparatus and components. The flow channels were constructed using three pipes with three different inner diameters of 21.0 mm, 47.0 mm and 95.0 mm. The flow direction was vertical upward co-current flow with liquid superficial velocity range of 0.025 m/s to 3.0 m/s and gas superficial velocity range of 0.025 m/s to 3.0 m/s, depending on the size of the pipe. The flow pattern investigation focuses on experimental work, which was based on systematic observation and measurements using a high-speed camera and some measuring apparatus. The void fraction measurement using the CECM sensor was integrated into two-phase flow system with constant electric current running in the pipe and data acquisition system controlled virtually via LabVIEW software. Both result of the flow pattern and void fraction graph were then compared to determine the type of flow pattern from the void fraction graph. Information from the previous studies and experiments were collected and the assumption of any theoretical simplifications were used as a reference. According to the result, the flow pattern in pipe can be easily determined using CECM