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Gustiono D.,Ibnu Sina Institute for Fundamental Science Studies | Gustiono D.,Agency for Assessment and Application of Technology | Wibowo E.,State University of Semarang | Othaman Z.,Ibnu Sina Institute for Fundamental Science Studies
Journal of Physics: Conference Series | Year: 2013

Semiconductor nanowires have been intensively investigated in order to study their unique fundamental and application properties that develop at the nano-scale. One of main problems in the growth of III-V semiconductor nanowire is uniformity both of in dimension and composition of chemical elements. We synthesized InGaAs nanowire on GaAs (111) substrate at 400 °C-480 °C temperatures for 30 minutes using MOCVD. The nanowires grow perpendicular to the substrate via direct impinging mechanism and they have hexagonal shape with diameter of 80-150 nm. Dimension of nanowire, length and diameter, increase with increases of growth temperature. Formations of tapering could be controlled with growth at lower temperature. © IOP Publishing Ltd 2013. Source

Noviyanti R.,Eijkman Institute for Molecular Biology | Noviyanti R.,The Ministry of Research and Technology RISTEK | Coutrier F.,Eijkman Institute for Molecular Biology | Coutrier F.,The Ministry of Research and Technology RISTEK | And 22 more authors.
PLoS Neglected Tropical Diseases | Year: 2015

Outside of Africa, P. falciparum and P. vivax usually coexist. In such co-endemic regions, successful malaria control programs have a greater impact on reducing falciparum malaria, resulting in P. vivax becoming the predominant species of infection. Adding to the challenges of elimination, the dormant liver stage complicates efforts to monitor the impact of ongoing interventions against P. vivax. We investigated molecular approaches to inform the respective transmission dynamics of P. falciparum and P. vivax and how these could help to prioritize public health interventions. Genotype data generated at 8 and 9 microsatellite loci were analysed in 168 P. falciparum and 166 P. vivax isolates, respectively, from four co-endemic sites in Indonesia (Bangka, Kalimantan, Sumba and West Timor). Measures of diversity, linkage disequilibrium (LD) and population structure were used to gauge the transmission dynamics of each species in each setting. Marked differences were observed in the diversity and population structure of P. vivax versus P. falciparum. In Bangka, Kalimantan and Timor, P. falciparum diversity was low, and LD patterns were consistent with unstable, epidemic transmission, amenable to targeted intervention. In contrast, P. vivax diversity was higher and transmission appeared more stable. Population differentiation was lower in P. vivax versus P. falciparum, suggesting that the hypnozoite reservoir might play an important role in sustaining local transmission and facilitating the spread of P. vivax infections in different endemic settings. P. vivax polyclonality varied with local endemicity, demonstrating potential utility in informing on transmission intensity in this species. Molecular approaches can provide important information on malaria transmission that is not readily available from traditional epidemiological measures. Elucidation of the transmission dynamics circulating in a given setting will have a major role in prioritising malaria control strategies, particularly against the relatively neglected non-falciparum species. Source

Kim J.-Y.,National Institute of Health | Goo Y.-K.,National Institute of Health | Goo Y.-K.,Kyungpook National University | Zo Y.-G.,Sungkyunkwan University | And 8 more authors.
PLoS ONE | Year: 2016

Background: Vivax malaria was successfully eliminated from the Republic of Korea (ROK) in the late 1970s but re-emerged in 1993. Two decades later as the ROK enters the final stages of malaria elimination, dedicated surveillance of the local P. vivax population is critical. We apply a population genetic approach to gauge P. vivax transmission dynamics in the ROK between 2010 and 2012. Methodology/Principal Findings: P. vivax positive blood samples from 98 autochthonous cases were collected from patients attending health centers in the ROK in 2010 (n = 27), 2011 (n = 48) and 2012 (n = 23). Parasite genotyping was undertaken at 9 tandem repeat markers. Although not reaching significance, a trend of increasing population diversity was observed from 2010 (HE = 0.50 ± 0.11) to 2011 (HE = 0.56 ± 0.08) and 2012 (HE = 0.60 ± 0.06). Conversely, linkage disequilibrium declined during the same period:IAS = 0.15 in 2010 (P = 0.010), 0.09 in 2011 (P = 0.010) and 0.05 in 2012 (P = 0.010). In combination with data from other ROK studies undertaken between 1994 and 2007, our results are consistent with increasing parasite divergence since re-emergence. Polyclonal infections were rare (3% infections) suggesting that local out-crossing alone was unlikely to explain the increased divergence. Cases introduced from an external reservoir may therefore have contributed to the increased diversity. Aside from one isolate, all infections carried a short MS20 allele (142 or 149 bp), not observed in other studies in tropical endemic countries despite high diversity, inferring that these regions are unlikely reservoirs. Conclusions: Whilst a number of factors may explain the observed population genetic trends, the available evidence suggests that an external geographic reservoir with moderate diversity sustains the majority of P. vivax infection in the ROK, with important implications for malaria elimination. © 2016 Kim et al.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source

Soedarsono J.W.,University of Indonesia | Kawigraha A.,University of Indonesia | Kawigraha A.,Agency for Assessment and Application of Technology | Sulamet-Ariobimo R.D.,Trisakti University | And 3 more authors.
Advanced Materials Research | Year: 2013

Limitation of iron ore reserve having high quality ore and of energy has enhanced development in iron and steel producing technology and method. The ITmk3 process is one of iron making technology that can cope with the problems. It uses composite pellet as feeding material. In this process the ratio between iron and carbon are very important. Carbon holds an important role in the reduction process of iron. The transformation from iron oxides to iron metal will complete if composite pellet contains enough carbon. This paper discusses the influence of carbon ratio in iron reduction process. Nickel saprolite and coal are used as iron and carbon source. They are grinded, crushed, sieved, mixed and formed in cylinders. The weight ratios of ores to coal are 1:1 and 2:1. The reduction held in a furnace at 1100°C for 60 minutes and 1250°C for 120 minutes. The results show that the reduction could not complete. Weak peak of FeNi is due to reduction process do not immediately follow the dehydroxylation process. © (2013) Trans Tech Publications, Switzerland. Source

Gunawan E.,Nagoya University | Sagiya T.,Nagoya University | Ito T.,Nagoya University | Kimata F.,Tono Research Institute of Earthquake Science | And 7 more authors.
Journal of Asian Earth Sciences | Year: 2014

We investigate the postseismic deformation of the 2004 Sumatra-Andaman earthquake (SAE) using 5years of Global Positioning System (GPS) data located in northern Sumatra. Continuous GPS data from northern Sumatra suggest that the relaxation time in the vertical displacement is longer than horizontal displacements. This implies that there are multiple physical mechanisms that control the postseismic deformation, which refer to afterslip and viscoelastic relaxation. In this study, we introduce an analysis strategy of postseismic deformation to simultaneously calculate multiple mechanisms of afterslip and viscoelastic relaxation. The afterslip inversion results indicate that the distribution of the afterslip and the coseismic slip are compensatory of each other. Also, afterslip has a limited contribution to vertical deformation in northern Sumatra. In our rheology model, we use a gravitational Maxwell viscoelastic response and the result indicates that the elastic layer thickness is 65±5km and the Maxwell viscosity is 8.0±1.0×1018Pas. We find that afterslip plus Maxwell viscoelastic relaxation are appropriate to explain the deformation in northern Sumatra. We also find that our rheology model reproduces the long-term features of the GPS time series in Thailand. Applying our rheology model to the data in Andaman Islands our afterslip estimation is located at the down-dip part of the plate boundary. Finally, we showed that our rheology model is applicable to the GPS datasets of postseismic deformation of the 2004 SAE located in northern Sumatra, Thailand, and Andaman-Nicobar, respectively. © 2014 Elsevier Ltd. Source

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