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Perylene Tetracarboxylic Diimide: Characterization and Its Role in the Electrical Properties of an Ag/N-BuHHPDI/PEDOT:PSS/p-Si Heterojunction Device
No full textThis paper reports on the thin film characterization of a synthesized small molecular semiconductor N-butyl-N′-(6-hydroxyhexyl) perylene-3,4,9,10-tetracarboxylic acid diimide (N-BuHHPDI) and its potential use in Ag/N-BuHHPDI/PEDOT:PSS/p-Si heterojunction device. The device is fabricated using spin coating of a conducting polymer PEDOT:PSS on p-Si substrate followed by thermal deposition of a 100-nm-thin layer of N-BuHHPDI. To complete the fabrication of Ag/N-BuHHPDI/PEDOT:PSS/p-Si heterostructure, silver (Ag) is used as the top electrode. The device shows non-ohmic and asymmetrical current–voltage (I–V) characteristics in dark conditions at 25°C which confirm the successful formation of rectifying heterojunction. Various diode parameters such as ideality factor (n), barrier height (ϕb), series resistance (Rs) and charge carrier mobility across the interface of the heterojunction are measured from the I–V characteristics. The non-ideal behavior of the diode is correlated with the film morphology obtained by atomic force microscopy. Fourier transformed infrared spectroscopy is performed to confirm the successful preparation of N-BuHHPDI. The fluorescence lifetime (22 ns) of the N-BuHHPDI thin film is measured via fluorescence spectroscopy. Different charge conduction mechanisms including the dominant one are studied for the fabricated device. © 2019, The Minerals, Metals & Materials Society
The Moderating Effects of Social Media Usage towards Fan Attachment in MotoGP
No full textThe purpose of this study was to investigate the relationships between MotoGP fans’ attachment with their favorite teams’ Facebook pages. Data were collected through survey method. The questionnaires were completed by 384 fans. Data were analyzed using Statistical Package of Social Science. Sport fans who have formed strong connections to their favorite team may be termed loyal fans. One popular communication tool for such fans is Facebook, which has been found to be an important medium for sharing news and events, yet few studies have examined the moderating of Facebook use in a sport context. Adopting the relational approach examining the determinants of sport-fan attachment, this study examined how Facebook use moderates the building of fan attachment. All independent variables together explain 78 percent of the variance (R Square) in Team Attachment which is highly significant as indicates by the f values 336.845. Findings revealed the t values of team attraction, social media and team involvement are positively related to team attachment. Facebook use was found to significantly reinforce their attachment. Specific implications for both theory and practice are discussed. Overall, respondents indicated they preferred content related to players, including injury and movement, as well as race result, suggesting they might prefer using Facebook as another way to receive information instead of choosing to actively engage with their favorite team. However, because results from modeling suggest engaging individuals on Facebook has positive impacts on future behavioral intentions, sport marketers should consider engaging individuals on Facebook while still fulfilling their need for information about players and game results. © 2020, Hampstead Psychological Associates. All rights reserved
Ternary molybdenum disulfide nanosheets-cobalt oxide nanocubes-platinum composite as efficient electrocatalyst for hydrogen evolution reaction
No full textA high-performance ternary composite electrocatalyst, consisting of a molybdenum disulfide-cobalt oxide-platinum (Mo–Co–Pt) composite is synthesized by facile hydrothermal methods and then used as an electrocatalyst for hydrogen evolution reaction (HER). The ternary composite of Mo–Co–Pt is characterized using transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and linear sweep voltammetry. The as-synthesized Mo–Co–Pt-modified glassy carbon electrode shows better electrocatalytic performance than that of pure molybdenum disulfide (MoS2) nanosheets and cobalt oxide (Co3O4) nanocubes. Besides, the ternary composite electrode exhibits Pt-like performance along with the smallest Tafel slope and superior electrocatalytic stability in an acidic medium. Based on BET specific surface area and electrochemical impedance spectroscopy measurements, the MoS2 nanosheets and Pt nanoparticles enhance HER activity of the Co3O4 nanocubes in the ternary composite due to the synergistic effect between the two-dimensional structure and large surface area of MoS2 nanosheets and excellent electrocatalytic activity of the Pt nanoparticles. © 2020 Elsevier Lt
Energy use analysis of the variable refrigerant flow (VRF) system versus the multi - split unit using TRNSYS
No full textThe usage of air - conditioning in the residential and commercial buildings is becoming necessary because of the enormous demand for thermal comfort and healthy indoor environment. In achieving human thermal comfort and healthy indoor environment in a large building, there are many types of air conditioning systems that can be used, including the multi - split type unit and the variable refrigerant flow (VRF) system. The present research analyses the annual energy use of the existing ACMV system (multi - split type ceiling cassette unit) installed in the examined building, which located in the tropical area and compares it with a VRF system. The TRNSYS software is used to simulate both of these systems in accordance with the existing building’s characteristics and its operation. The existing building’s characteristics and its operation are obtained by conducting the site survey and field measurements in the building. In the current paper, the bin method is used to estimate the annual energy consumption for these systems. Based on the simulation results, the existing ACMV system consumes more energy in comparison to the VRF system by 13.62%. In addition, the annual operating cost of these systems has shown that the VRF system has a lower annual operating cost in comparison to the existing ACMV system by 13.63%. Besides that, the VRF system can accommodate an estimated payback period of around 6.6 years and an internal rate of return of 12.75%. The result has suggested that the VRF system has a great potential in energy savings and could reduce the electricity consumption in a large building significantly. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature
Politeness strategies of the pembayun(s) in the bride-kidnapping practices of sasak culture
No full textBride-kidnapping is considered a violation of human rights in many cultures worldwide, but among the Sasak people of Lombok, it has deep customary implications. While the act itself is consensual between the couple, it is an occasion for the families to confront each other and discuss settlements or dispute the offers between each other. The negotiation is a show of tradition or customary norms where politeness strategies is observed during the discussions between the two disputing parties affected by the bride-kidnapping. During the discussions, rituals such as Sejati, Selabar, and Sorong Serah are conducted to neutralise anxiety, address face attacks and reduce disputes that may have arisen due to the bridekidnapping. In these three rituals, the language resources of the representatives of both families, also known as Pembayun (adat leaders), is to negotiate and come to a settlement through polite discourse. This study is an ethnographic enquiry and data were analysed based on Brown and Levinson's model of politeness. The study revealed that the most preferred strategy was negative politeness used by both the Pembayun in the bridekidnapping rituals. The notion of politeness and the strategies in which it is achieved in communication is culture-bound and culture-specific. © 2020 Universiti Putra Malaysia Press
Genomic Insights into Two Colistin-Resistant Klebsiella pneumoniae Strains Isolated from the Stool of Preterm Neonate During the First Week of Life
No full textBackground: Klebsiella pneumoniae is a major opportunistic pathogen frequently associated with nosocomial infections, and often poses a major threat to immunocompromised patients. In our previous study, two K. pneumoniae (K36 and B13), which displayed resistance to almost all major antibiotics, including colistin, were isolated. Both isolates were not associated with infection and isolated from the stools of two preterm neonates admitted to the neonatal intensive care unit (NICU) during their first week of life. Materials and Methods: In this study, whole genome sequencing was performed on these two clinical multidrug resistant K. pneumoniae. We aimed to determine the genetic factors that underline the antibiotic-resistance phenotypes of these isolates. Results: The strains harbored blaSHV-27, blaSHV-71, and oqxAB genes conferring resistance to cephalosporins, carbapenems, and fluoroquinolones, respectively, but not harboring any known plasmid-borne colistin resistance determinants such as mcr-1. However, genome analysis discovered interruption of mgrB gene by insertion sequences gaining insight into the development of colistin resistance. Conclusion: The observed finding that points to a scenario of potential gut-associated resistance genes to Gram negative (K. pneumoniae) host in the NICU environment warrants attention and further investigation. © Copyright 2020, Mary Ann Liebert, Inc., publishers 2020
The impact of big data on firm performance in hotel industry
No full textBig data has increasingly appeared as a frontier of opportunity in enhancing firm performance. However, it still is in early stages of introduction and many enterprises are still un-decisive in its adoption. The aim of this study is to propose a theoretical model based on integration of Human-Organization-Technology fit and Technology-Organization-Environment frameworks to identify the key factors affecting big data adoption and its consequent impact on the firm performance. The significant factors are gained from the literature and the research model is developed. Data was collected from top managers and/or owners of SMEs hotels in Malaysia using online survey questionnaire. Structural Equation Modelling (SEM) is used to assess the developed model and Adaptive Neuro-Fuzzy Inference Systems (ANFIS) technique is used to prioritize adoption factors based on their importance levels. The results showed that relative advantage, management support, IT expertise, and external pressure are the most important factors in the technological, organizational, human, and environmental dimensions. The results further revealed that technology is the most important influential dimension. The outcomes of this study can assist the policy makers, businesses and governments to make well-informed decisions in adopting big data. © 2019 Elsevier B.V
Evolution of sustainability in global green building rating tools
No full textGreen building rating tools (GBRTs) are well-known and important instruments for assessing building sustainability. GBRTs constantly upgrade to meet rapid development, one of which is achieving a reasonable balance among the “three pillars” of sustainability, namely, environmental, social and economic sustainability. This study analyzes the changes and trends in the three sustainability pillars of GBRT and reinforces the previous GBRT longitudinal studies in terms of research sample, time span, equal terms, and research depth. Ten global GBRTs are selected by specific screening principles, and a unified criterion framework is presented to compare these selected GBRTs on equal terms. The changes of GBRTs are then analyzed on three levels, namely, categories, subcategories, and criteria. The results show that in the past three decades, there is a continuous decrease in the weight of the environmental category, an obvious increase in the weight of the social category and a little rise in the wight of the “economic” category. “Pollution,” “physical comfort,” and “flexibility” are identified as “sensitive criteria” of environmental, social, and economic categories, respectively, given their significant changes; they are also critical factors for the evolution of GBRT for the past three decades. © 2020 Elsevier Lt
Characteristics and health effect of heavy metals on non-exhaust road dusts in Kuala Lumpur
No full textThis study aimed to assess the concentrations and health effect of trace metals [cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn)] on the road dust of selected locations in the city of Kuala Lumpur. Sampling was conducted thrice at four locations, namely, Tun Razak Road, Raja Abdullah Road, Tunku Abdul Rahman (TAR) Road, and Ayer Molek Road. The concentrations of trace metals in road dust were analyzed by inductively coupled plasma mass spectrometry. TAR Road presented the highest Cd, Cu, Ni, and Pb contents compared with the other roads. The pollution level of trace metals in road dust was assessed by pollution index and pollution load index (PLI), showing that all studied locations were highly contaminated except Ayer Molek Road. Based on the PLI value, the sequence of pollution in descending order is as follows: TAR Road > Raja Abdullah Road > Tun Razak Road > Ayer Molek Road. Health risk assessment was performed to assess the health effects of carcinogenic and noncarcinogenic pollutants caused by the exposure to trace metals in road dust on adults and children. Based on the integrated hazard index values for children at all locations, >1 indicates a possible noncarcinogenic effect. All incremental lifetime cancer risk values for adult and children at all locations are within acceptable limits and are considered safe. © 201
Description, molecular characteristics and Wolbachia endosymbionts of Onchocerca borneensis Uni, Mat Udin & Takaoka n. sp. (Nematoda: Filarioidea) from the Bornean bearded pig Sus barbatus Müller (Cetartiodactyla: Suidae) of Sarawak, Malaysia
No full textBackground: The genus Onchocerca Diesing, 1841 includes species of medical importance, such as O. volvulus (Leuckart, 1893), which causes river blindness in the tropics. Recently, zoonotic onchocercosis has been reported in humans worldwide. In Japan, O. dewittei japonica Uni, Bain & Takaoka, 2001 from wild boars is a causative agent for this zoonosis. Many filarioid nematodes are infected with Wolbachia endosymbionts which exhibit various evolutionary relationships with their hosts. While investigating the filarial fauna of Borneo, we discovered an undescribed Onchocerca species in the bearded pig Sus barbatus Müller (Cetartiodactyla: Suidae). Methods: We isolated Onchocerca specimens from bearded pigs and examined their morphology. For comparative material, we collected fresh specimens of O. d. dewittei Bain, Ramachandran, Petter & Mak, 1977 from banded pigs (S. scrofa vittatus Boie) in Peninsular Malaysia. Partial sequences of three different genes (two mitochondrial genes, cox1 and 12S rRNA, and one nuclear ITS region) of these filarioids were analysed. By multi-locus sequence analyses based on six genes (16S rDNA, ftsZ, dnaA, coxA, fbpA and gatB) of Wolbachia, we determined the supergroups in the specimens from bearded pigs and those of O. d. dewittei. Results: Onchocerca borneensis Uni, Mat Udin & Takaoka n. sp. is described on the basis of morphological characteristics and its genetic divergence from congeners. Molecular characteristics of the new species revealed its close evolutionary relationship with O. d. dewittei. Calculated p-distance for the cox1 gene sequences between O. borneensis n. sp. and O. d. dewittei was 5.9%, while that between O. d. dewittei and O. d. japonica was 7.6%. No intraspecific genetic variation was found for the new species. Wolbachia strains identified in the new species and O. d. dewittei belonged to supergroup C and are closely related. Conclusions: Our molecular analyses of filarioids from Asian suids indicate that the new species is sister to O. d. dewittei. On the basis of its morphological and molecular characteristics, we propose to elevate O. d. japonica to species level as O. japonica Uni, Bain & Takaoka, 2001. Coevolutionary relationships exist between the Wolbachia strains and their filarial hosts in Borneo and Peninsular Malaysia.[Figure not available: see fulltext.] © 2020 The Author(s)