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Glacier phototroph blooms on the surfaces of ice sheets and glaciers cause albedo reduction, leading to increased melting rates. We observed seasonal changes in the abundance of phototrophs on the Qaanaaq Ice Cap in northwestern Greenland from June to August 2014, and reproduced these changes using numerical and empirical models. The phototroph community on the ice surface mainly consisted of the glacier alga Ancylonema nordenskioldii and the cyanobacterium Phormidesmis priestleyi. The glacier alga appeared on the ice surface in late June, after which its abundance increased exponentially throughout the melting period. A logistic growth model designed for snow algal growth reproduced the measured exponential increases, suggesting that growth could be explained using the model as a function of the ice melting duration. Cyanobacteria appeared and their abundance increased in late July but did not change exponentially thereafter. The abundance of cyanobacteria was explained with an empirical model expressed as a function of the amount of mineral dust on the bare ice surface. Our numerical and empirical models for reproducing glacier algae and cyanobacteria could be useful for quantifying the albedo reduction caused by their growth and the melt rates of the Greenland ice sheet and glaciers in the future.

The objective of this study was to investigate the current soil properties in lowland paddy fields in Peninsular Malaysia and to assess the long-term changes in the soil fertility status during 50 ...

Understanding of the long-term soil fertility trends is the basis for rational and sustainable management of the soil resources in agricultural fields. In tropical Asia, the Green Revolution initia...

Since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, morphological abnormalities in lepidopteran insects, such as shrinkage and/or aberration of wings, have been reported. Butterflies experimentally exposed to radiocesium also show such abnormalities. However, because of a lack of data on absorbed dose and dose-effect relationship, it is unclear whether these abnormalities are caused directly by radiation. We conducted a low dose-rate exposure experiment in silkworms reared from egg to fully developed larvae on a

To understand the long-term behavior of radiocesium in the biological processes of a forest ecosystem, its concentration in Japanese epigeic earthworms (Megascolecidae), litter, and soil, and the ambient dose equivalent rates, were investigated after the Fukushima Dai-ichi Nuclear Power Plant accident. The metabolism of radiocesium in the earthworms was also investigated in the laboratory, and its biological half-life (Tb) was estimated. The concentration of ¹³⁷Cs in the habitat soil and litter changed from 2014 to 2016, with levels in the litter going from 44.9 Bq/g dw (in 2014) to 45.3 Bq/g dw (2015) and 10.7 Bq/g dw (2016); in soil, these values were 9.79 Bq/g dw, 7.14 Bq/g dw and 18.0 Bq/g dw, respectively. By contrast, no significant changes were observed in the concentrations in the earthworms, which were 4.87 Bq/g fw, 5.30 Bq/g fw and 4.67 Bq/g fw in 2014, 2015, and 2016, respectively. The ambient dose equivalent rates at the sampling site declined significantly over these three years, going from 2.15 μSv/h to 1.68 μSv/h and 1.35 μSv/h, mostly corresponding to physical decay of radiocesium. The majority (95%) of the ¹³⁷Cs in the earthworms, observed via autoradiography, was concentrated primarily in the intestine. The clearance of ¹³⁷Cs from the earthworms was described by dual exponential functions: the half-life in the rapid loss due to gut clearance was 0.10 days and a second slower loss due to physiological clearance was 27.4 days.

This study investigated general physicochemical properties of tea garden soils at the alluvial plain of Cong River in Tan Cuong commune, Vietnam. Four gardens were selected as study sites on three ...

The effective radiation dose of palladium under the assumption that it is contaminated with 107Pd (1 Bq/g) is estimated through four exposure pathways: the inhalation of airborne particles emitted from an automobile exhaust control catalyst, ingestion via food or drinking water, ingestion of palladium in saliva after release from a dental application, and inhalation exposure of dust in the work place. The highest dose (3.17 × 10−9 μSv/y) was estimated in adult workers manufacturing palladium products. Considering variations in parameters and possible exposure pathways, it is concluded that this is the critical group for determining the clearance level of 107Pd. The clearance level, which is defined as a 107Pd concentration providing less than 10 μSv/y in any exposure pathway, is calculated as 3.16 × 103 Bq/g.

Understanding the pathways of 137Cs transfer to spiders as generalist predators is useful to assess the long-term recycling of 137Cs through the food chain in forest ecosystems. Approximately 6.5 years after the Fukushima Dai-ichi Nuclear Power Plant accident, we collected spider samples at two different habitats (in a forest interior and along a river) in a forest and determined their 137Cs activity concentrations and stable carbon and nitrogen isotope ratio values (δ13C and δ15N). Across the locations, 137Cs was detected in all spiders, indicating that a significant fraction of the deposited 137Cs is still bioavailable. The geometric means of the transfer factor (Tag) values were 1.3 × 10−3 m2 kg−1 and 0.8 × 10−3 m2 kg−1 for the spiders in the forest interior and along the river, respectively. There were no significant differences in the 137Cs activity concentration and Tag value between the locations. In contrast, the δ13C and δ15N for the spiders were significantly different between the locations, indicating different food resources of the spiders. The preliminary results indicate that the transfer of 137Cs to spiders can be a useful indicator of 137Cs recycling in forest ecosystems, but the transfer pathways remain difficult to identify because of high variability.

Since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, morphological abnormalities in lepidopteran insects, such as shrinkage and/or aberration of wings, have been reported. Butterflies experimentally exposed to radiocesium also show such abnormalities. However, because of a lack of data on absorbed dose and dose–effect relationship, it is unclear whether these abnormalities are caused directly by radiation. We conducted a low dose-rate exposure experiment in silkworms reared from egg to fully developed larvae on a 137CsCl-supplemented artificial diet and estimated the absorbed dose to evaluate morphological abnormalities in pupal wings. We used 137CsCl at 1.3 × 103 Bq/g fresh weight to simulate 137Cs contamination around the FDNPP. Absorbed doses were estimated using a glass rod dosimeter and Monte Carlo particle transport simulation code PHITS. Average external absorbed doses were approximately 0.24 (on diet) and 0.016 mGy/day (near diet); the average internal absorbed dose was approximately 0.82 mGy/day. Pupal wing structure is sensitive to radiation exposure. However, no significant differences were observed in the wing-to-whole body ratio of pupae between the 137CsCl-exposure and control groups. These results suggest that silkworms are insensitive to low dose-rate exposure due to chronic ingestion of high 137Cs at a high concentration.

Surface albedo of snow and ice is substantially reduced by inorganic impurities, such as aeolian mineral dust (MD) and black carbon (BC), and also by organic impurities, such as microbes that live in the snow. In this paper, we present the temporal changes of surface albedo, snow grain size, MD, BC and snow algal cell concentration observed on a snowpack in northwest Greenland during the ablation season of 2014 and our attempt to reproduce the changes in albedo with a physically based snow albedo model. We also attempt to reproduce the effects of inorganic impurities and the red snow algae (Sanguina nivaloides) on albedo. Concentrations of MD and red snow algae in the surface snow were found to increase in early August, while snow grain size and BC were found to not significantly change throughout the ablation season. Surface albedo was found to have decreased by 0.08 from late July to early August. The albedo simulated by the model agreed with the albedo observed during the study period. However, red snow algae exerted little effect on surface albedo in early August. This is probably owing to the abundance of smaller cells (4.9×104 cells L−1) when compared with the cell abundance of red snow reported by previous studies in the Arctic region (∼108 cells L−1). The simulation of snow albedo until the end of the melting season, with a snow algae model, revealed that the reduction in albedo attributed to red snow algae could equal 0.004, out of a total reduction of 0.102 arising from the three impurities on a snowpack in northwest Greenland. Finally, we conducted scenario simulations using the snow albedo model, coupled with the snow algae model, in order to simulate the possible effects of red snow blooming on snow albedo under warm conditions in northwest Greenland. The result suggests that albedo reduction by red snow algal growth under warm conditions (surface snow temperature of +1.5 ∘C) reached 0.04, equivalent to a radiative forcing of 7.5 W m−2 during the ablation season of 2014. This coupled albedo model has the potential to dynamically simulate snow albedo, including the effect of organic and inorganic impurities, leading to proper estimates of the surface albedo of snow cover in Greenland.

Surface albedo of snow and ice is substantially reduced by inorganic impurities, such as aeolian mineral dust (MD) and black carbon (BC), and also by organic impurities, such as microbes that live in the snow. In this paper, we present the temporal changes of surface albedo, snow grain size, MD, BC, and snow algal cell concentration observed on a snowpack in northwest Greenland during the ablation season of 2014 and our attempt to reproduce the changes in albedo with a physically based snow albedo model. We also attempt to reproduce the effects of inorganic impurities and the red snow algae (Chlamydomonas nivalis) on albedo. Concentrations of MD and red snow algae in the surface snow were found to increase in early August, while snow grain size and BC were found to not significantly change throughout the ablation season. Surface albedo was found to have decreased by 0.08 from late July to early August. The albedo simulated by the model agreed with the albedo observed during the study period. However, red snow algae exerted little effect on surface albedo in early August. This is probably owing to the abundance of smaller cells (4.9 × 104 cells L^-1) when compared with the cell abundance of typical red algal snow (~ 108 cells L−1). The simulation of snow albedo until the end of the melting season, with an algal growth model, revealed that the reduction in albedo attribute to red algae could equal 0.004, out of a total reduction of 0.102 arising from the three impurities on a snowpack in northwest Greenland. Finally, we conducted scenario simulations using the snow albedo model, coupled with the algal growth model, in order to simulate the possible effects of red algal blooming on snow albedo under warm conditions in northwest Greenland. The result suggests that albedo reduction by red snow algal growth under warm conditions (surface snow temperature of +1.5 °C) reached 0.04, equivalent to a radiative forcing of 7.5 W m−2 during the ablation season of 2014. This coupled albedo model has the potential to dynamically simulate snow albedo, including the effect of organic and inorganic impurities, leading to proper estimates of the surface albedo of snow cover in Greenland.

To understand the behavior of radioactive cesium (134Cs+137Cs) in terrestrial invertebrates, chronological changes in the concentration of radioactive Cs in arthropods from different trophic levels were investigated after the Fukushima Daiichi Nuclear Power Plant accident. In addition, the level of radioactive Cs in earthworms, representing the detritivores, was also investigated. The median radioactive Cs concentration in the rice grasshopper (Oxya yezoensis) and the Emma field cricket (Teleogryllus emma) was 0.46 and 0.15 Bq/g fresh weight (fw) in 2012, respectively, which dropped continuously to 0.05 and 0.01 Bq/g fw in 2016. In contrast, no significant reduction in radioactive Cs concentration was observed in the Joro spider (Nephila clavata) in which the concentration was 0.31 Bq/g fw in 2012 and remained at 0.14 Bq/g fw in 2016. The comparison of radioactive Cs concentration at each trophic level showed that the amount in detritivorous earthworms was 85 times higher than in herbivorous grasshoppers. This suggests that detritus food web could be a primary pathway for migration of radioactive Cs through food webs.

Research on the recycling of useful elements in spent nuclear fuels of light-water cooling reactors is progressing. Palladium (Pd), a fission product in high-level radioactive waste, is one of the elements that can be recovered and recycled. Even if the Pd recycling system is successfully established, 107Pd contamination will be unavoidable. In this report, we review the lifecycle of Pd (applications, environmental levels, and human exposure) with respect to setting clearance levels for 107Pd. The major applications of Pd in Japan are catalysts for automobile exhausts and chemical industries, followed by dental prostheses and electrical devices. The World Health Organization reported a daily uptake of Pd from drinking water and food of 0.03 and

The morphological and chemical properties of homegardens in the beach ridges with interspersed swales (BRIS) soils were evaluated in order to find a clue for developing sustainable agricultural management. Field survey and soil sampling were conducted at the homegardens and secondary forests in Sungai Ular Village and in the experimental farm of Malaysian Agriculture Research Institute (MARDI), Cherating Station. Chemical fertilizers including ash, charcoal waste and plant litter were applied to the homegardens in both the inland-ward area (HG-I) and in the shoreline area (HG-S). Manure was applied in HG-I and seafood waste from fish processing was buried in the soils in HG-S. High correlation was found between total carbon (T-C) and cation exchange capacity (CEC), indicating soil organic matter was the determinant factor for CEC in the very sandy BRIS soils. The levels of T-C, total nitrogen (T-N), and CEC at 0–10 cm in HG-I in parallel with increasing ages of homegardens. The soils in 0–10 cm an...

Mechanical responses to electric stimulation in a side-chain chiral smectic A elastomer composed of cholesterol derivative mesogens were investigated. Electric-field-induced shear deformation, caused by the electroclinic effect, was observed in the chiral smectic A phase with a wide temperature range between 40°C and 120°C. In addition, electric-field-induced bend deformation was recognized in the temperature region of the isotropic state.

Biodiversity decline in rapidly expanding oil palm plantations is of global concern. Many studies have demonstrated that fauna species diversity is lower in oil palm plantations than forests. However, information about the flow-on effects of these declines in species diversity on ecosystem functioning is scarce for oil palm plantations. Litter decomposition performed by soil organisms is a vital ecosystem function that regulates nutrient cycling and carbon sequestration. Some studies have found a high level of redundancy among litter decomposing species. In order to evaluate the effects of the conversion of forests to oil palm plantations on decomposition, we investigated the abundance and biomass of soil macro-invertebrates at sites in two oil palm plantations and a secondary forest in Malaysia. Biodiversity of soil macro-invertebrates were lower in the oil palm plantations than in the secondary forest. The abundance and biomass of surface–living litter transformers was lower in oil palm plantations than forest, probably due to the isolated piles of frond litter that occur in plantations, instead of the more continuous litter layer observed in forests. However, we found dense populations of wood (litter)–feeding termites in the thick rachises of fronds heaped on the ground surface. A pantropical earthworm species, Pontoscolex corethrurus, which buries the litter through cast deposition, abounded more in the oil palm plantations than in the secondary forest. These characteristics of soil macro-invertebrates have also been reported in other oil palm plantations. Thus, we conclude that the conversion of forests to oil palm plantations may reduce diversity of soil macro-invertebrates, increase the heterogeneity of macro-invertebrates distribution and decrease populations of some functional groups of soil macro-invertebrates. However, overall, forest conversion does not appear to have a negative impact on the decomposition process to a great extent, owing to the colonization of plantation sites by other groups of decomposer animals that are favored by disturbance and/or the great amount of localized input of fresh fronds pruned at the time of fruit harvesting.

Snow and ice algal communities were investigated on four glaciers in the Suntar-Khayata Mountain Range in eastern Siberia in Russia over three melting seasons from 2012 to 2014. Two taxa of green algae and five taxa of cyanobacteria were observed on the glaciers. The algal community was dominated by green algae: Ancylonema nordenskioldii in the lower bare ice area and Chloromonas sp. in the upper snow area. The total algal bio-volume showed altitudinal variation, ranging from 0.03 to 4.0 mL m−2, and was greatest in the middle of the glaciers. The altitudinal variations in the algal community were similar on all studied glaciers, suggesting that they are typical in this region. Observations over the three years revealed that there was no significant change in the community structure, but a significant change in the total biomass. Since the mean summer air temperature was significantly higher in 2012 when algal biomass was greater, the difference in algal biomass among the years is probably due to the duration of surface melting. The community structure on the studied glaciers is similar to those on glaciers in Arctic and sub-Arctic regions.

Little is known about the effect of soil disinfection on bacterial communities. Soils were treated with an effective chemical fumigant chloropicrin and biofumigant mustard greens (Brassica juncea). While mustard greens did not affect the soil bacterial community structures very much, chloropicrin greatly reduced soil biomass and bacterial species richness. Chloropicrin also influenced the bacterial community structure, making the phylum Firmicutes dominant by occupying about 75%. In more than two months, the proportion of Firmicutes was reduced to the basal level, and the phyla Bacteroidetes and Proteobacteria became dominant. Since mustard greens worked as carbon sources for soil reduction, soils were treated with wheat bran and a low concentration of ethanol. Soil reduction with wheat bran and ethanol did not influence the soil bacterial community structures. Beta diversity analyzed by Principal Coordinate Analysis showed that bacterial communities in the soils except chloropicrin-applied soils formed a cluster. All together, biofumigant mustard greens, a probable substitute for chloropicrin, were demonstrated to cause much less damage on soil bacterial community than chemical chloropicrin.

Soil bacterial community structures in terraced rice fields and abandoned lands in a hilly and mountainous area were analyzed using 16S rRNA gene sequences. The DGGE band patterns of each soil were similar. Based on pyrosequencing data, the richness and diversity of bacterial species were slightly higher in paddy fields than in other soils. A beta-diversity analysis clearly indicated that the bacterial community structure in paddy fields differed from those in non-paddy field lands and crop fields that had not been used as a paddy field. These results may reflect the history of land use.

Endometrial cancer is one of the most common female pelvic cancers and has been considered an androgen-related malignancy. Several studies have demonstrated the anti-cell proliferative effect of androgen on endometrial cancer cells; however, the mechanisms of the anti-cancer effect of androgen remain largely unclear. 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2), which catalyzes the conversion of E2 to E1, is known to be upregulated by androgen treatment in breast cancer cells. In this study, we therefore focused on the role of androgen on estrogen dependence in endometrial cancer. Dihydrotestosterone (DHT) was found to induce 17β-HSD2 mRNA and protein expression in HEC-1B endometrial cancer cells. DHT could also inhibit cell proliferation of HEC-1B when induced by estradiol treatment. In 19 endometrioid endometrial adenocarcinoma (EEA) tissues, intratumoral DHT concentration was measured by liquid chromatography/electrospray tandem mass spectrometry and was found to be significantly correlated with 17β-HSD2 immunohistochemical status. We further examined the correlations between 17β-HSD2 immunoreactivity and clinicopathological parameters in 53 EEA tissues. 17β-HSD2 status was inversely associated with the histological grade, clinical stage, and cell proliferation marker Ki-67, and positively correlated with progesterone receptor expression. 17β-HSD2 status tended to be positively associated with androgen receptor status. In 53 EEA cases, the 17β-HSD2-positive group tended to have better prognosis than that for the negative group with respect to progression-free survival and endometrial cancer-specific survival. These findings suggest that androgen suppresses the estrogen dependence of endometrial cancer through the induction of 17β-HSD2 in endometrial cancer.

Snow algal bloom is a common phenomenon on melting snowpacks in polar and alpine regions and can substantially increase melting rates of the snow due to the effect of albedo reduction on the snow surface. In order to reproduce algal growth on the snow surface using a numerical model, temporal changes in snow algal abundance were investigated on the Qaanaaq Glacier in northwest Greenland from June to August 2014. Snow algae first appeared at the study sites in late June, which was approximately 94 hours after air temperatures exceeded the melting point. Algal abundance increased exponentially after the appearance, but the increasing rate became slow after late July, and finally reached 3.5 × 107 cells m-2 in early August. We applied a logistic model to the algal growth curve and found that the algae could be reproduced with an initial cell concentration of 6.9 × 102 cells m-2, a growth rate of 0.42 d-1, and a carrying capacity of 3.5 × 107 cells m-2 on this glacier. This model has the potential to simulate algal blooms from meteorological data sets and to evaluate their impact on the melting of seasonal snowpacks and glaciers.

Although an estimation of forest biomass is essential for the development of a carbon storage baseline in the ''Reducing Emissions from Deforestation and Deg- radation in Developing Countries'' scheme, few have been conducted in logged-over rain forests of Southeast Asia. We measured the aboveground and belowground biomass in logged-over mixed dipterocarp forests growing on an infertile soil with bleached white sand (Sabal) and on a clay and nutrient-rich soil (Balai Ringin) in Sarawak, Malaysia. We established four 0.5-ha plots on each site and calcu- lated the biomass. Basal area and stand density of large trees (diameter at breast height, DBH C 10 cm) were

Endometrial carcinoma is the most common malignancy found in the female genital tract, and its incidence, particularly that of the most common histological type, endometrioid endometrial carcinoma, has increased recently.1,2 The estimated 5-year overall survival for early-stage endometrial carcinoma is 82% but decreases remarkably to 67% for regional disease and 16% for distant disease.3 Although the majority of patients (approximately 83%) are diagnosed as having stage I or II disease, those with advanced-stage endometrial carcinoma or unfavorable pathological characteristics have poor prognosis.2 Therefore, it is important to evaluate the clinical and biological markers in patients with endometrial carcinoma to predict recurrence after surgery and to evaluate the indications of additional therapies appropriately. Corticotropin-releasing hormone (CRH) is a major regulator of the stress response to internal and external factors.4 The stress response is characterized by an activation of the autonomic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis.5 Corticotropin-releasing hormone is secreted by the paraventricular nucleus of the hypothalamus in response to stress and stimulates the anterior lobe of the pituitary gland to release adrenocorticotropic hormone through its interaction with CRH receptors 1 (CRHR1) and 2 (CRHR2).6 Adrenocorticotropic hormone in turn stimulates the adrenocortex to produce and secrete cortisol.6,7 The actions of CRH and its receptors are thought to play important roles in various stress-related disorders.8 Recent studies have demonstrated that CRH is present not only in the central nervous system but also in various peripheral organs.9 Corticotropin-releasing hormone mediates endocrine responses to stress by activating the HPA axis as well as via direct actions in the periphery.10,11 Of note, the expression of CRH and its receptors has also been reported in several types of carcinoma.12,13 Specifically, Miceli14 reported CRH, CRHR1, and CRHR2 immunoreactivity in endometrial carcinoma. Although stress is known to be a promoter of tumor growth,15 it remains unclear whether CRH, CRHR1, or CRHR2 immunoreactivity in endometrial carcinoma is a risk factor for poor prognosis. In this study, we tested the hypothesis that the expression of CRH, CRHR1, and CRHR2 in endometrial carcinoma is associated with poor prognosis.

In order to better understand the source of minerals on the dark-colored ice, located in the Greenland ice sheet ablation zone, we analyzed the Sr and Nd isotopic ratios of minerals in cryoconite, which were collected from glaciers in northwest and southwest Greenland. We focused on the following: (i) comparison of the isotopes of minerals in cyroconite with those in sediments from local and distant areas, (ii) regional variations in western Greenland, and (iii) spatial variations across an individual a glacier. The mineral components of the cryoconite showed variable Sr and Nd isotopic ratios (87Sr/86Sr: 0.711335 to 0.742406, εNd (0): −33.1 to −22.9), which corresponded to those of the englacial dust and moraine on and around the glaciers but were significantly different from those of the distant deserts that have been considered to be primary sources of mineral dust on the Greenland Ice Sheet. This suggests that the minerals within the cryoconites were mainly derived from local sediments, rather than from distant areas. The Sr ratios in the northwestern region were significantly higher than those in the southwestern region. This is probably due to geological differences in the source areas, such as the surrounding glaciers in each region. The isotopic ratios further varied spatially within a glacier (Qaanaaq and Kangerlussuaq areas), indicating that the silicate minerals on the glaciers were derived not from a single source but from multiple sources, such as englacial dust and wind-blown minerals from the moraine surrounding the glaciers.

Pelvic exenteration has attained an important role in the treatment of advanced or recurrent cervical cancer for obtaining a complete cure or longer disease-free survival. The purpose of this study was to evaluate patients undergoing pelvic exenteration and to determine the clinical features associated with outcome and survival.We retrospectively analyzed the records of 12 patients who underwent pelvic exenteration for uterine cervical cancer between July 2002 and August 2011.Two patients had primary stage IVA cervical adenocarcinoma and 10 patients had recurrent cervical cancer. Eight patients underwent anterior pelvic exenteration, 3 patients underwent total pelvic exenteration, and 1 patient underwent posterior pelvic exenteration. With a median duration of follow-up of 22 months (range 3-116 months), 5 patients were alive without recurrence. Of 5 patients with no evidence of disease, 4 were recurrent or residual tumor, all of whom had common factors, such as a tumor size ≤ 30 mm, negative surgical margins, complete resection, and no lymph node involvement. The 5-year overall survival rate for 12 patients was 42.2 %. Ileus was the most common complication (42 %) and post-operative intestinal anastomosis leaks developed in 3 patients, but no ureteral anastomosis leaks occurred.Pelvic exenteration is a feasible surgical procedure in advanced and/or recurrent cervical cancer patients with no associated post-operative mortality, and the only therapeutic option for complete cure or long-term survival; however, post-operative complications frequently occur.