Investigating the Influence of Non‐Spectral Matrix Effects in the Determination of Twenty‐Two Trace Elements in Rock Samples by ICP‐QMS

The influence of non‐spectral matrix effects on the determination of twenty‐two trace elements (Rb, Sr, Y, Cs, Ba, lanthanides, Pb, Th and U) in rock samples using ICP‐MS was investigated. Three types of multi‐element solutions were synthesised containing the twenty‐two trace elements, In, Tl and ten major rock‐forming elements with varying mass fractions mimicking the compositions of basalt, peridotite and dolomite. The synthetic solutions were conditioned to have dilution factors (DF) of 1000–10000. The extent of sensitivity suppression relative to the DF = 10000 solution became more significant for smaller DF solutions, which was not constant across different elements in a single solution but displayed general dependence on m/z. This indicates that at least two internal standards (e.g., In and Tl) are required for the correction of sensitivity variation. On the basis of the results, a new isotope dilution‐internal standardisation method for the determination of twenty‐two trace elements with ICP‐MS was developed, in which the sensitivity variation was corrected by monitoring two enriched isotopes, ¹¹³In and ²⁰³Tl. This method, coupled with the quantitative correction of interference from oxides and hydroxides, achieved precise determination of twenty‐two trace elements in some rock reference materials with reproducibilities of ±2% for basaltic to andesitic samples.     

Application of an impact plate – Bedload transport measuring system for high-speed flows

To achieve the sustainable use of dams, the development of methods for sediment management in reservoirs is required. One such method includes the use of Sediment Bypass Tunnels (SBTs) to divert sediment around a dam, thereby preventing sedimentation in the reservoir. However, SBTs are prone to severe invert abrasion caused by the high sediment flux. Therefore, it is necessary to establish a measurement system of the sediment transport rate in these tunnels. One system to measure sediment transport in rivers is the Swiss plate geophone, which can register plate vibrations caused by particle impact. In Japan, the Japanese pipe microphone is used, and sediment transport is measured based on the sound emitted by the particle impact. In this study an attempt was made to optimize the advantages of both systems by fixing a microphone and an acceleration sensor to a steel plate. The results of calibration experiments with this new system are presented and compared with the existing methods. It was found that the acceleration sensor can detect sediment particles larger than 2 mm in diameter. Moreover, a new parameter, referred to as the detection rate, was introduced to describe the correlation between the actual amount of sediment and the registered output. Finally, two parameters - the saturation rate and hit rate - are introduced and exhibit strong correlation with the detection rate.     

Optimization of causative factors using logistic regression and artificial neural network models for landslide susceptibility assessment in Ujung Loe Watershed,South Sulawesi Indonesia

Landslide susceptibility maps(LSMs) play a vital role in assisting land use planning and risk mitigation. This study aims to optimize causative factors using logistic regression(LR) and an artificial neural network(ANN) to produce a LSM. The LSM is produced with 11 causative factors and then optimized using forward-stepwise LR(FSLR), ANN, and their combination(FSLR-ANN) until eight causative factors were found for each method. The ANN method produced superior validation results compared with LR. The ROC values for the training data set ranges between 0.8 and 0.9. On the other hand, validation with the percentage of landslide fall into LSM class high and very high, ANN method was higher(92.59%) than LR(82.12%). FSLR-ANN with nine causative factors gave the best validation results with respect to area under curve(AUC) values, and validation with the percentage of landslide fall into LSM class high and very high. In conclusion, ANN was found to be better than LR when producing LSMs. The best Optimization was combination of FSLR-ANN with nine causative factors and AUC success rate 0.847, predictive rate 0.844 and validation with landslide fall into high and very high class with 91.30%. It is an encouraging preliminary model towards a systematic introduction of FSLR-ANN model for optimization causative factors in landslide susceptibility assessment in the mountainous area of Ujung Loe Watershed.     

Geochemistry and Sm‐Nd chronology of a Stannern‐group eucrite,Northwest Africa 7188

We report the results of a detailed study of the basaltic eucrite Northwest Africa (NWA) 7188, including its mineralogical and bulk geochemical characteristics, oxygen isotopic composition, and ^147,146Sm‐^143,142Nd mineral isochron ages. The texture and chemical composition of pyroxene and plagioclase demonstrate that NWA 7188 is a monomict eucrite with a metamorphic grade of type 4. The oxygen isotopic composition and the Fe/Mn ratios of pyroxene confirmed that NWA 7188 belongs to the howardite–eucrite–diogenite meteorite suite, generally considered to originate from asteroid 4 Vesta. Whole‐rock TiO₂, La, and Hf concentrations and a CI chondrite‐normalized rare earth element pattern are in good agreement with those of representative Stannern‐group eucrites. The ^147,146Sm‐^143,142Nd isochrons for NWA 7188 yielded ages of 4582 ± 190 and 4554 +17/?19 Ma, respectively. The closure temperature of the Sm‐Nd system for different fractions of NWA 7188 was estimated to be >865 °C, suggesting that the Sm‐Nd decay system has either been resistant to reheating at ~800 °C during the global metamorphism or only partially reset. Therefore, the ¹⁴⁶Sm‐¹⁴²Nd age of NWA 7188 corresponds to the period of initial crystallization of basaltic magmas and/or global metamorphism on the parent body, and is unlikely to reflect Sm‐Nd disturbance by late reheating and impact events. In either case, NWA 7188 is a rare Stannern‐group eucrite that preserves the chronological information regarding the initial crustal evolution of Vesta.     

High‐resolution national land use scenarios under a shrinking population in Japan

In sharp contrast with the global trend in population growth, certain developed countries are expected to experience rapid national population declines. Considering future land use scenarios that include depopulation is necessary to evaluate changes in ecosystem services that affect human well‐being and to facilitate comprehensive strategies for balancing rural and urban development. In this study, we applied a population‐projection‐assimilated predictive land use modeling (PPAP‐LM) approach, in which a spatially explicit population projection was incorporated as a predictor in a land use model. To analyze the effects of future population distributions on land use, we developed models for five land use types and generated projections for two scenarios (centralization and decentralization) under a shrinking population in Japan during 2015–2050. Our results suggested that population centralization promotes the compaction of built‐up areas and the expansion of forest and wastelands, while population decentralization contributes to the maintenance of a mixture of forest and cultivated land.     

Occurrence of Two Distinct Types of Tissue Inhibitors of Metallo-proteinases-2 in Fugu rubripes

In this study, genes of two distinct tissue inhibitors of metalloproteinases-2 （TIMP-2） from Japanese puffer fish Fugu rubripes, Fugu TIMP-2a and TIMP-2b, were cloned. The open reading frames of Fugu TIMP-2a and TIMP-2b cDNAs are composed of 660 and 657 nucleotides and 220 and 219 amino acids, respectively. Both Fugu TIMP-2s contain 12 cysteine residues, which might form six disulfide bonds as in other animals＇ TIMP-2s. Reverse-transcribed polymerase chain reaction analysis showed the mRNAs of Fugu TIMP-2a and TIMP-2b to be expressed in some tissues examined with different expression patterns. These findings suggest that the two distinct Fugu TIMP-2s might perform different functions in Fugu tissues.     

Formal education and disaster response of children: evidence from coastal villages in Indonesia

Natural Hazards - Although children are exposed to a high mortality risk during disasters, what determines their disaster response, especially during earthquakes, remains largely unexplored. The...     

New records of three <Emphasis Type="Italic">Paraprionospio</Emphasis> species (Polychaeta: Spionidae) from Korean waters

The spionid polychaete Paraprionospio pinnata (Ehlers 1901) has been widely reported from Korean waters. We examined some specimens belonging to the genus Paraprionospio that had been collected from Korean waters, and identified them as Paraprionospio coora Wilson, 1990, Paraprionospio cordifolia Yokoyama, 2007 and Paraprionospio patiens Yokoyama, 2007, which are new to the fauna of Korea. The present study suggests misidentification of the specimens that have been previously reported as P. pinnata from Korean waters.     

Food sources of benthic animals on intertidal and subtidal bottoms in inner Ariake Sound,southern Japan,determined by stable isotopes

To evaluate the relative importance of possible food sources, including riverine particulate organic matter, reeds, benthic microalgae, seaweeds, cultured laver (Porphyra) and coastal phytoplankton, for commercial bivalves and co-occurring benthic animals, 73 macrofaunal species were collected from intertidal and subtidal soft bottoms in the inner part of Ariake Sound, Kyushu, southern Japan, and their isotopic compositions were analyzed. The results revealed that (1) both intertidal and subtidal food webs were constituted of 3 trophic levels, (2) suspension-feeding bivalves utilize a mixture of benthic microalgae and coastal phytoplankton, and omnivores and carnivores incorporate benthic microalgae and phytoplankton through their intermediate prey, and (3) 3 bivalves (Scapharca kagoshimensis, Modiolus metcalfei and Atrina lischkeana) inhabiting both intertidal and subtidal bottoms showed similar seasonal fluctuations, suggesting no difference in the diet composition among the species and between the 2 habitats. We conclude that a large biomass of benthic microalgae which was approximately equal to that of phytoplankton and the strong tidal currents that would resuspend benthic microalgae and transport them to subtidal bottom areas account for the benthic microalgal and phytoplankton based trophic structure in the inner part of Ariake Sound.