Makara Journal of Science
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The Diversity of Wild Banana Species (Genus Musa) in Java
No full textThe diversity of wild banana species (genus Musa, listed in Flora of Java) has been revised. The present taxonomic study is based on morphological characteristics observed in the herbarium specimens deposited at the Herbarium Bogoriense (BO), living collections in the Bogor Botanical Garden, the Cibodas Botanical Garden, and during the explorations done at Mt. Salak, West Java. Eight species of Musa (Musa acuminata, M. balbisiana, M. coccinea, M. ornata, M. salaccensis, M. sanguinea, M. textilis and M. velutina) and seven infraspecific taxa of M. acuminata are recognized in Java, of which two infraspecific taxa are endemic. West Java is the center of distribution for the wild banana species in Java. Taxonomic descriptions including an identification key are presented
Extraction of the Proton Charge Radius from Experiments
No full textThe static properties of hadrons, such as their radii and other moments of the electric and magnetic distributions, can only be extracted using theoretical methods and cannot be directly measured from experiments. As a result, discrepancies between the extracted values from different precision measurements can exist. The proton charge radius, rp, which is extracted either from electron-proton (e-p) elastic scattering data or from hydrogen atom spectroscopy, seems to be no exception. The value rp = 0.84087(39) fm extracted from muonic hydrogen spectroscopy is about 4% smaller than that obtained from e-p scattering or standard hydrogen spectroscopy. The resolution of this so-called proton radius puzzle has been attempted in many different ways over the past six years. The present article reviews these attempts with a focus on the methods of extracting the radius. 
The Artificial Leaf: Recent Progress and Remaining Challenges
No full textThe prospect of a device that uses solar energy to split water into H2 and O2 is highly attractive in terms of producing hydrogen as a carbon-neutral fuel. In this mini review, key research milestones that have been reached in this field over the last two decades will be discussed, with special focus on devices that use earth-abundant materials. Finally, the remaining challenges in the development of such “artificial leaves” will be highlighted
Reproductive Characteristics of Female Egg-carrying Buntingi, Xenopoecilus oophorus, an Endemic Fish to Lake Poso in Central Sulawesi
No full textReproduction characteristic of female egg-carrying buntingi, Xenopoecilus oophorus had been studied. This research was conducted at Lake Poso, Central Sulawesi, Indonesia. Specimens were collected monthly from August 2012 to July 2013 at four sampling stations around the lake. Macroscopic observations of ovarian maturity level and gonadosomatic index revealed a long reproductive period during the rainy season, with four spawning peaks in November, January, February and April. The highest total fecundity was 135 oocytes, and the highest batch fecundity was 36 oocytes. Analysis of the oocyte diameter frequency distribution showed X. oophorus is a multiple spawner. Batch fecundity was correlated (r = 0.78) with body weight
Identification of Quantitative Trait Loci (QTL) for Awn, Incomplete Panicle Exertion and Total Spikelet Number in an F2 Population Derived from A Backcross Inbred Line, Bio-148, and the Recurrent Parent, IR64
No full textAn F2 rice population developed from a cross between a backcross inbred line (BIO-148) and its recurrent parent (IR64) was used to identify quantitative trait loci (QTL) for awn, panicle exertion and total spikelet number. BIO-148 is a BC2F8 line derived from a cross between IR64 (a high-yielding lowland rice variety) and Gajah Mungkur (an upland tropical japonica rice variety). Two hundred plants were grown in the greenhouse, and their DNAs were isolated for genotyping using SSR markers. Panicle exertion was observed during the grain-filling stage. The awn length of the seed and the total spikelet number per panicle were observed after harvesting. A total of four QTLs were identified using single-marker regression with LOD>3, explaining 8.4-18.1% of phenotypic variation. A QTL for awn was identified on Chromosome 8. A QTL for incomplete panicle exertion was identified on Chromosome 4. Two QTLs for total spikelet number were identified on Chromosome 4, in which the BIO-148 allele contributed to a higher number of spikelets per panicle. The QTLs identified in this study will be useful in the improvement of yield potential for modern lowland indica rice varieties by harnessing the hidden useful alleles from upland tropical japonica rice varieties
Atomic Ensemble Effects and Non-Covalent Interactions at the Electrode–Electrolyte Interface
No full textCyanide-modified Pt(111) electrodes have been recently employed to study atomic ensemble effects in electrocatalysis. This work, which will be briefly reviewed, reveals that the smallest site required for methanol dehydrogenation and formic acid dehydration is composed of three contiguous Pt atoms. By blocking these trigonal sites, the specific adsorption of anions, such as sulfate and phosphate, can be inhibited, thus increasing the rate of oxygen reduction reaction by one order of magnitude or more. Moreover, alkali metal cations affect hydrogen adsorption on cyanide-modified Pt(111). This effect is attributed to the non-covalent interactions at the electrical double layer between specifically adsorbed anions or dipoles and the alkali metal cations. A systematic investigation is conducted on the effect of the concentration of alkali metal cations. Accordingly, a simple model that reproduces the experimental observations accurately and enables the understanding of the trends in the strength of the interaction between M+ and CNad when moving from Li+ to Cs+, as well as the deviations from the expected trends, is developed. This simple model can also explain the occurrence of super-Nernstian shifts of the equilibrium potential of interfacial proton-coupled electron transfers. Therefore, the model can be generally applied to explain quantitatively the effect of cations on the properties of the electrical double layer. The recently reported effects of alkali metal cations on several electrocatalytic reactions must be mediated by the interaction between these cations and chemisorbed species. As these interactions seem to be adequately and quantitatively described by our model, we expect the model to also be useful to describe, explain, and potentially exploit these effects
Determination of Carbofuran on Hydrophilic Interaction Liquid Chromatography using TSKgel®Amide-80 as a Stationary Phase
No full textHydrophilic interaction liquid chromatography (HILIC) equipped with an environmentally friendly capillary column was employed to investigate the retention behavior of carbofuran; a polar stationary phase was used as well. Several conditions were conducted to investigate the retention behavior of carbofuran, such as a comparison study TSKgel®Amide-80 with another polar column, a comparison study retention behavior of carbofuran on various wavelengths, the water content effect on HILIC mode, the effect of buffer concentration on HILIC mode, and the analytical performance of carbofuran. The results showed that TSKgel®Amide-80 exhibited a better performance than other polar stationary phases in carbofuran determination, and observations at wavelengths of 251 and 254 nm showed higher absorbance for carbofuran than others. In addition, the increase of water content and salt buffer concentration in the mobile phase led to a shorter retention time. The recovery of this method was 101 ± 10.1%, while the limit of detection and the limit of quantification were 0.66 ppm and 2.22 ppm, respectively. Consequently, TSKgel®Amide-80 offers a good performance in carbofuran determination, even with the application of 10 cm length column capillary liquid chromatograph
Photoproduction of π0-Mesons from the Nucleon and Deuteron
No full textThe photoproduction of π0-mesons from the nucleon and deuteron has been studied for incidents of photon energies up to 1.5 GeV. By using the MAID-2007 model for the process on the nucleon, we predict results for the unpolarized and helicity-dependent total cross sections of the semi-exclusive reaction γd→π0X (X=np+d) with the inclusion of rescattering effects. We find that rescattering effects yield a substantially large contribution. The extracted results are compared with the available experimental data and a satisfactory agreement is obtained. In addition, the contribution of γd→π0X (X=np+d) to the finite GDH integral has been evaluated by explicit integration up to 1.5 GeV and a total value of 256.96 µb has been obtained. Convergence of the GDH integral has been reached. 
Synchrotron Infrared Spectroscopy of Microporous Materials
No full textThis review describes the ways in which synchrotron infrared radiation can be used to perform infrared spectroscopy on catalyst materials. The enhanced brightness of the synchrotron source over a conventional laboratory source allows for microspectroscopy to be performed on single crystals of microporous materials down to 10 microns in size. A second application was performed in the far-infrared region, which is generally difficult using laboratory instruments. The review presents typical results from both areas and discusses future prospects
The Explosive Sensitivity on the Complex Formation of 3-Nitro-1,2,4-Triazol-5-One and Metal Ions Based on Density Functional Study
No full textThe explosive sensitivity upon the formation of supramolecular interaction between the nitro group of 3-nitro-1,2,4-triazol-5-one (NTO) and metal ions (Mn+ = Li+, Na+, Be2+ and Mg2+) has been investigated using Density Functional Theory at B3LYP/6-311++G** level of theory. The bond dissociation energy (BDE) of the C1–N6 trigger bond has also been discussed for the NTO monomer and the corresponding complexes. The interaction and bond dissociation energy of the C6–N7 trigger bond follow the order of NTO-Be2+ > NTO-Mg2+ > NTO-Li+ > NTO-Na+ > NTO monomer. The enhancement of the trigger bond dissociation energy in comparison with the NTO monomer correlates well with the complex interaction energies, trigger bond length, and charge transfer. The analyses of electron density shifts have shown that the electron density of the nitro group shifts toward the C1–N6 trigger bond upon the formation of the supramolecular interaction. As result, the trigger bond is strengthened and the sensitivity of NTO is reduced. Some of the calculated results agree with the experimental values