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A well‐ordered polygonal crack pattern is frequently observed on the outcrop surface of columnar joints. The crack pattern's geometry and topology result from the volume contraction of solidified lava during thermal dissipation. In this study, we conducted field measurements of columnar joints at four different sites with various lithologies in Japan to understand the influence of geography and lithological character on their geometric characteristics. Drone‐aided photography and computer‐based image analysis enabled us to examine the constituent polygons' geometric attributes and their statistics with high accuracy. This methodology revealed a relationship between the geometry and topology of the polygonal crack patterns. Moreover, we established a positive correlation between the polygon area and the number of vertices of a polygon at each study site, irrespective of lithology, or geographic position. These results are consistent with previous investigational studies, in particular starch‐based analog experiments. Plain Language Summary: "Gallery of rock prisms carved by Nature" When erupted lava is rapidly cooled by seawater, numerous cracks penetrate inward, resulting in a splendid landscape called "columnar jointing." It is a mysterious aggregate of prismatic rocks with polygonal (often hexagonal) cross‐sections, the most famous example being Giant's Causeway in Ireland. Careful examination of columnar jointing over several localities has revealed several scientific laws hidden behind these joints' shapes. First, there is a relationship between the type of polygon in the cross‐section and its area. When the area is small, the shape tends to be a pentagon; but if the area is medium or large, the shape is likely to be a hexagon or heptagon, respectively. Interestingly, this tendency holds regardless of the rocks' locality, chemical character, or the prism's length scale. Second, the extent to which the polygons shape is distorted is not random but is kept below a threshold. Again, this threshold's magnitude is universal and independent of the locality, character, and prism scale. These two findings imply an unknown mechanism governing how Nature carves these magnificent prismatic sculptures during the rapid cooling of lava. Key Points: A drone was used to obtain aerial images of polygon patterns on columnar joints' outcrop surfaces at four different sites in JapanUnexpected correlations between geometrical characteristics of the cross‐section of prisms were revealed by image processingConclusions obtained from field measurements were consistent with those of analog experiments based on starch slurry [ABSTRACT FROM AUTHOR]

Mekong River-Tonle Sap Lake is a typical river-lake interaction system in a monsoon area. The Tonle Sap Lake (TSL) is the largest freshwater lake in Southeast Asia, and is an important component in lower Mekong River (MR) Basin. Water resource managers are highly concerned about the potential impact of climate change on the MR-TSL hydrological system in the future. Thus, it is necessary to develop a numerical model which can simulate MR-TSL interaction system for the assessment of potential impact of natural climatic variations on hydrological cycle in this area. The main objective of this study was to model a river-lake interaction system for water resource assessment in TSL area. The distinctive feature of this study is to develop an integrated River Lake Water Exchange (RLWE) model and couple it to a grid-based distributed hydrological model (YHyM) for MR-TSL system. Using the coupled model, discharge contribution to TSL from tributaries, lake water volume, water exchange between the MR and TSL, and consumptive water use in TSL area were simulated. The potential impact of climate change on TSL hydrological system was also assessed through the application of the coupled model. Several future scenarios were analyzed, and predictions of water budgets within the interaction system under different scenarios were made. [ABSTRACT FROM AUTHOR]

In the context of climate change, salinity intrusion into rivers has been, and will be, one of the most important issues for coastal water resources management. A combination of changes, including increased temperature, change in regional rainfall, especially sea level rise (SLR) related to climate change, will have significant impacts on this phenomenon. This paper presents the outcomes of a study conducted in the Mekong Delta of Vietnam (MKD) for evaluating the effect of sea water intrusion under a new SLR scenario. Salinity intrusion was simulated by one-dimensional (1D) modeling. The relative sea level projection was constructed corresponding to the RCP 6.0 emission scenario for MKD based on the statistical downscaling method. The sea level in 2050 is projected to increase from 25 cm to 30 cm compared to the baseline period (in 2000). Furthermore, the simulated results suggested that salinity greater than 4 g/l, which affects rice yield, will intrude up to 50-60 km into the river. Approximately 30,000 ha of agricultural area will be affected if the sea level rise is 30 cm. [ABSTRACT FROM AUTHOR]

Abstract: Impacts of vegetation change on streamflow have long been an issue for concern and climate variability can also greatly affect streamflow. Climate change refers to the persistent change in climate over long periods of time due to either natural or as a result of human activity. It is very important to quantify the contribution of climate change and human activities on the change of streamflow and provide a scientific basis for future land conservation planning and river ecological conservation. In this study, non-parametric Pettitt mutation method was employed to detect trends and changes in annual streamflow for the period of 1961 to 2008 in the Da River Basin (55000km2), which is the most important tributary of Red River. An upward trend was found in annual streamflow, with an abrupt change identified in 1993 at the Laichau and Tabu stations in the upstream of the Hoa Binh Reservoir. In addition, the Normalized Difference Vegetation Index (NDVI) data from 1981 to 2006 was used to detect vegetation change in the past 26 years. The difference between average annual accumulated NDVI during before and after 1993 and linear slope of annual accumulated NDVI from 1982 to 2006 was calculated. The discharge data was divided into a baseline period (before 1993) and a period of change. Sensitivity-based method and model simulation method were then proposed to separate different effects from climate and human activities. Results indicated that the streamflow is more sensitive to precipitation than potential evaportransportation (PET). Effects of climate variability on streamflow estimated using the sensitivity-based method was weak in the downsream catchment of Tabu station, and strong in the upstream catchment of Laichau station, where the climate effects accounted for about 30% of total streamflow changes. Effects of human activities on streamflow accounted for about 60% both in the Laichau and Tabu catchments. Human activities are the main factor to affect the changes of inflow into the Hoa Binh Reservoir, and climate change also plays an important role. [Copyright &y& Elsevier]

A grid-based erosion model is developed by integrating the distributed hydrological model, BTOPMC, with the modified USLE to estimate soil erosion and sediment outflow during single storms. The possible sheet, rill, channel erosion types, and sediment transport processes are considered within each grid under the model structure. Instead of representing the sheet erosion and rill erosion separately, the classic USLE method is modified to simulate the lumped sheet–rill erosion during storms. In the modification, the runoff ratio and a relevant correction coefficient are brought into the R-factor which improves the model’s applicability in predicting erosion during single storms. Instead of representing a grid with a unique erosion type, a channel component is assumed to exist in each grid, and its width varies with the upstream contributing area of the grid. This assumption avoids the problems that are caused by the difference between the channel widths in the upstream area and the downstream area if the grid is simply recognized as a channel grid. It also enables the model to be applicable in simulating soil erosion and sediment outflow from a large catchment. Through a case study in the Lushi catchment, China, the results show an overall satisfactory accuracy for the selected events. Moreover, by analyzing the spatial distribution of soil erosion or deposition, the erosion-prone areas are identified for the prioritization purpose. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a framework to estimate pollutant export coefficients from commonly available in-stream water quality monitoring data and using these pollutant export coefficients for catchment scale modelling of pollution loadings. A case study is presented to illustrate the framework in the Fuji River catchment, Japan. The total pollution loading was estimated by constructing an empirical source contribution model. The estimated pollutant export coefficients were used to estimate non-point source pollution loadings and point source loadings were estimated using the data collected from major wastewater treatment plants within a catchment. The non-point source loadings, especially from forest and agriculture, were found to be the major contributor whereas the point source loadings were found to be a minor contributor of total organic matter and nutrient loadings in the study catchment. These results are encouraging especially given the pressing need to identify appropriate management practices to improve the water quality within the Fuji River catchment. It is recommended to investigate further the required number of water quality monitoring stations, sampling frequencies and sampling duration of water quality constituents to enhance the robustness and usefulness of the proposed methodology. [Copyright &y& Elsevier]

This article discusses a study which calculated the potential evapotranspiration and potential interception evaporation in different land cover areas and compared them with the Mekong River basin for the period of 1981-2000. The researchers used the Shuttleworth-Wallace (S-W) model that recognizes vegetation diversity. They concluded that use of the implementation of the S-W model results in a physically sound estimate of the potential evapotranspiration from soil moisture, which accounts for changing land surface conditions.

Potential evapotranspiration (PET) is a key input to hydrological models. Its estimation has often been via the Penman--Monteith (P--M) equation, most recently in the form of an estimate of reference evapotranspiration (RET) as recommended by FAO-56. In this paper the Shuttleworth--Wallace (S--W) model is implemented to estimate PET directly in a form that recognizes vegetation diversity and temporal change without reference to experimental measurements and without calibration. The threshold values of vegetation parameters are drawn from the literature based on the International Geosphere--Biosphere Programme land cover classification. The spatial and temporal variation of the LAI of vegetation is derived from the composite NOAA-AVHRR normalized difference vegetation index (NDVI) using a method based on the SiB2 model, and the Climate Research Unit database is used to provide the required meteorological data. All these data inputs are publicly and globally available. Consequently, the implementation of the S--W model developed in this study is applicable at the global scale, an essential requirement if it is to be applied in data-poor or ungauged large basins. A comparison is made between the FAO-56 method and the S--W model when applied to the Yellow River basin for the whole of the last century. The resulting estimates of RET and PET and their association with vegetation types and leaf area index (LAI) are examined over the whole basin both annual and monthly and at six specific points. The effect of NDVI on the PET estimate is further evaluated by replacing the monthly NDVI product with the 10-day product. Multiple regression relationships between monthly PET, RET, LAI, and climatic variables are explored for categories of vegetation types. The estimated RET is a good climatic index that adequately reflects the temporal change and spatial distribution of climate over the basin, but the PET estimated using the S--W model not only reflects the changes in climate, but also the vegetation distribution and the development of vegetation in response to climate. Although good statistical relationships can be established between PET, RET and/or climatic variables, applying these relationships likely will result in large errors because of the strong non-linearity and scatter between the PET and the LAI of vegetation. It is concluded that use of the implementation of the S--W model described in this study results in a physically sound estimate of PET that accounts for changing land surface conditions. [ABSTRACT FROM AUTHOR]

The plausible long-term trend of precipitation in China and its association with El Niño-southem oscillation (ENSO) are investigated by using non-parametric techniques. It is concluded that a greater number of decreasing trends, are observed than are expected to occur by chance. Geographically, the decreasing trend was concentrated in most parts of China, including the Songliao River, Hai River, Huai River, Yellow River, Zhujiang River, and southern part of the Yangtze River basins, whereas an increasing trend appeared primarily in the western and middle parts of China, mainly including the Inland River basin, and the northern part of the Yangtze River basins. Monthly mean precipitation for the summer and early autumn months generally decreased, with the greatest decrease occurring in August. The precipitation in spring from January to April and later autumn, including September and October, tended to increase, The teleconnection between precipitation and ENSO has been investigated by using the non-parametric Kendall's r. The correlation coefficients between the southern oscillation index (SOI) and precipitation show the areas with positive or negative associations. Approximately 20% of the stations exhibit statistically significant correlations between SOI and precipitation, of which 70% show a negative correlation, with most of them appearing in southeast China and several appearing in northwest and northeast China. Similar regional patterns are also observed when the precipitation records are further subdivided into El Niño, La Niña, and neutral periods. Statistical tests for the three kinds of time series were carried out using the non-parametric Wilcoxon rank-sum test and it is noted that the stations with significant differences in precipitation averages are mainly marked in the Yellow River basin and south China. The frequencies of below- and above-average precipitation that occurred during the El Niño, La Niña, and neutral periods are estimated as well. The result shows that greater precipitation may be associated with El Niño episodes in south China, but drought may easily occur during El Niño episodes in the Yellow River basin. [ABSTRACT FROM AUTHOR]

Analyzes the water resources in China's Yellow River using the system dynamics approach. Development of a model to evaluate the sustainability of the water resource system; Simulation of the system to acquire the dynamic character of the main elements affecting water demand and supply in the study area; Exploration of various water supply demands scenarios; Estimation of the sustainability index for different sub-regions.

The Heihe River Basin (HRB) is the second largest inland river basin in China, characterized by high diversity in geomorphology and irrigated agriculture in middle reaches. To improve the knowledge about the relationship between biotic and hydrological processes, this study used Global Inventory Modeling and Mapping Studies Normalized Difference Vegetation Index (NDVI) data (1982-2006) to analyze spatiotemporal variations in vegetation growth by using the Mann-Kendall test together with Sen's slope estimator. The results indicate that 10.1% and 1.6% of basin area exhibit statistically significant (p < 0.05) upward and downward trends, and maximum magnitude is 0.066/10a and 0.026/10a, respectively. More specifically, an increasing trend was observed in the Qilian Mountains and Hexi Corridor and a decreasing trend detected in the transitional region between them. Increases in precipitation and temperature may be one possible reason for the changes of vegetation growth in the Qilian Mountains. And decreasing trend in transitional region may be driven by the changes in precipitation. Increases of irrigation contribute to the upward trend of NDVI for cropland in the Hexi Corridor, reflecting that agricultural development becomes more intensive. Our study demonstrates the complexity of the response of vegetation growth in the HRB to climate change and anthropogenic activities and correspondingly adopting mechanistic ecological models capable of describing both factors is favorable for reasonable predictions of future vegetation growth. It is also indicated that improving irrigation water use efficiency is one practical strategy to balance water demand between human and natural ecosystems in the HRB.

Lacking observation data for calibration constrains applications of hydrological models to estimate daily time series of streamflow. Recent improvements in remote sensing enable detection of river water-surface width from satellite observations, making possible the tracking of streamflow from space. In this study, a method calibrating hydrological models using river width derived from remote sensing is demonstrated through application to the ungauged Irrawaddy Basin in Myanmar. Generalized likelihood uncertainty estimation (GLUE) is selected as a tool for automatic calibration and uncertainty analysis. Of 50,000 randomly generated parameter sets, 997 are identified as behavioral, based on comparing model simulation with satellite observations. The uncertainty band of streamflow simulation can span most of 10-year average monthly observed streamflow for moderate and high flow conditions. Nash-Sutcliffe efficiency is 95.7% for the simulated streamflow at the 50% quantile. These results indicate that application to the target basin is generally successful. Beyond evaluating the method in a basin lacking streamflow data, difficulties and possible solutions for applications in the real world are addressed to promote future use of the proposed method in more ungauged basins., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

This report describes a fatal case Prototheca zopfii genotype 2 infection in an immunosuppressed patient. The patient was a 62-year-old housewife who presented general malaise in April 2011. Hairy cell leukemia was highly suspected. Chemotherapy was started because the patient developed severe pancytopenia in October 2011. Itraconazole capsules (100 mg/day) and trimethoprim (320 mg/day) plus sulfamethoxazole (1600 mg/day) combinations were orally administered for prophylaxis of fungal infections. Of BacT/ALERT 3D FA aerobic culture bottles and FN anaerobic culture bottles, only FA aerobic blood culture bottles produced positive reactions when the patient developed fever in January 2012. Gram-staining of blood culture bottles revealed Gram-negative elliptical sporangia. Culturing on Sabouraud dextrose agar produced smooth and creamy white, yeast-like colonies. Partial DNA sequences of the nuclear 18S rDNA and 28S rDNA D1/D2 domains of the isolated strain were identical to those of P. zopfii genotype 2. The MICs and minimal lethal concentrations of antifungals revealed that it was susceptible to amphotericin B and itraconazole. The patient died, at which time plasma (1 → 3)-β-D-glucan was positive (131 pg/mL)., (Copyright © 2014. Published by Elsevier Ltd.)

Suspended sediment concentration of a river can provide very important perspective on erosion or soil loss of one river basin ecosystem. The changes of land use and land cover, such as deforestation or afforestation, affect sediment yield process of a catchment through changing the hydrological cycle of the area. A sediment rating curve can describe the average relation between discharge and suspended sediment concentration for a certain location. However, the sediment load of a river is likely to be undersimulated from water discharge using least squares regression of log-transformed variables and the sediment rating curve does not consider temporal changes of vegetation cover. The Normalized Difference Vegetation Index (NDVI) can well be used to analyze the status of the vegetation cover well. Thus long time monthly NDVI data was used to detect vegetation change in the past 19 years in this study. Then monthly suspended sediment concentration and discharge from 1988 to 2006 in Laichau station were used to develop one new sediment rating curve and were validated in other Asian basins. The new sediment model can describe the relationship among sediment yield, streamflow, and vegetation cover, which can be the basis for soil conservation and sustainable ecosystem management.

Primary lateral sclerosis (PLS) is clinically defined as a disorder selectively affecting the upper motor neuron (UMN) system. However, recently it has also been considered that PLS is heterogeneous in its clinical presentation. To elucidate the association of PLS, or disorders mimicking PLS, with 43-kDa TAR DNA-binding protein (TDP-43) abnormality, we examined two adult patients with motor neuron disease, which clinically was limited almost entirely to the UMN system, and was followed by progressive frontotemporal atrophy. In the present study, the distribution and severity, and biochemical profile of phosphorylated TDP-43 (pTDP-43) in the brains and spinal cords were examined immunohistochemically and biochemically. Pathologically, in both cases, frontotemporal lobar degeneration with ubiquitin inclusions (FTLD-U) was evident, with the most severe degeneration in the motor cortex. An important feature in both cases was the presence of Bunina bodies and/or ubiquitin inclusions, albeit very rarely, in the well preserved lower motor neurons. The amygdala and neostriatum were also affected. pTDP-43 immunohistochemistry revealed the presence of many positively stained neuronal cytoplamic inclusions (NCIs) and dystrophic neurites/neuropil threads in the affected frontotemporal cortex and subcortical gray matter. By contrast, such pTDP-43 lesions, including NCIs, were observed in only a few lower motor neurons. pTDP-43 immunoblotting revealed that fragments of ∼25-kDa were present in the cortices, but not in the spinal cord in both cases. Genetically, neither of the patients had any mutation in the TDP-43 gene. In conclusion, we consider that although PLS may be a clinically significant disease entity, at autopsy, the majority of such clinical cases would present as upper-motor-predominant amyotrophic lateral sclerosis with FTLD-TDP., (© 2011 Japanese Society of Neuropathology.)

A distributed hydrological model, YHyM, was integrated with the export coefficient concept and applied to simulate the nutrient load in the Mekong River Basin. In the validation period (1992-1999), Nash-Sutcliffe efficiency was 76.4% for discharge, 65.9% for total nitrogen, and 45.3% for total phosphorus at Khong Chiam. Using the model, scenario analysis was then performed for the 2020s taking into account major anthropogenic factors: climate change, population, land cover, fertilizer use, and industrial waste water. The results show that the load at Kompong Cham in 2020s is 6.3 x 10(4)tN a(-1) (+13.0% compared to 1990s) and 4.3 x 10(3)tP a(-1) (+24.7%). Overall, the noticeable nutrient sources are cropland in the middle region and urban load in the lower region. The installation of waste water treatment plants in urban areas possibly cut 60.6%N and 19.9%P of the estimated increase in the case without any treatment.