Causes of long-term changes in organic pollution of a river system with increasing population : a case study in the Kurosegawa River, Higashi-Hiroshima, Hiroshima

The Kurosegawa River, a polluted small river, flows through Higashi-Hiroshima, Hiroshima, where the population has increased steadily within the last decade. In order to clarify the impact of urbanization on the quality of the river water, changes in the state of organic pollution were studied in relation to population, construction of sewers and septic tanks in a recent 13-year period (1989-2001). Improvement in water quality (as indicated by BOD) was observed in the central area of the city, possibly as a result of the co11struction of sewers and septic tanks. In contrast, the BOD tended to increase in the lower reaches of the river. The pollutant flow analysis indicated that inflow of pollutant from a sewage treatment plant contributed to a significant proportion of the load. A simulation suggested that, with increasing population and sewage water, the BOD in the lower reaches of the river would be higher in the future because of the increase in the load from the plant. Based on the pollutant flow analysis, some solutions for reducing organic pollution are suggested.本研究の一部は学園都市づくり交流会議の地域課題研究事業の補助を受けて行われたものである

Periphyton contribution to nitrogen dynamics in the discharge from a wastewater treatment plant

To evaluate the importance of periphyton to nitrogen dynamics in the discharge from wastewater treatment plants (WWTPs), we examined changes in total and inorganic nitrogen content downstream from a WWTP on the Kurose River in Hiroshima Prefecture, Japan. At 0.7 km downstream of the WWTP (point A), NH4+-N was the dominant form of inorganic nitrogen, but concentrations decreased rapidly to 5 km downstream (point B). In contrast, no significant change in the [NO2– + NO3–]-N concentration was observed between the two points. Total nitrogen (TN) load decreased significantly between the two points, suggesting that sorption and/or denitrification occurred in the river channel. Potential rates of nitrogen sorption and transformation by periphyton were determined in a laboratory experiment in which changes in the nitrogen content of river water were examined in an acrylic chamber with periphyton. Nitrification and nitrogen removal occurred mainly in the periphyton. The contributions of periphyton activity to TN and NH4+-N decrease in the field, as estimated from the results of the laboratory experiments, were 6%–18% and 23%–72%, respectively. These results suggest that periphyton plays an important role in decreasing NH4+-N concentration in the discharge from wastewater treatment plants

Environmental condition and residents’ awareness of the Hannoogawa River, a concrete-lined stream in Higashi-Hiroshima City, Japan

半尾川（はんのをがわ）は，広島県東広島市中心部の西条地区を北から南に流れるコンクリート三面護岸化された小河川である。この川の環境に関する状況と将来の環境改善に向けた課題を明らかにするために，水質調査，水生生物調査，周辺住民の半尾川に対する認識についてのアンケート調査を実施した。水質調査の結果，BODは1.1~3.7 mg L-1の範囲にあり，やや汚染されていることが示唆された。しかし，トラップによる生物調査では全国水生生物調査で指定されている指標生物8種が確認され，この中には比較的きれいな水の指標生物も含まれていた。住民の意識調査の結果，最近10年以内に転入してきた住民は，それ以前から住んでいる住民にくらべ，半尾川の環境に関心が薄い傾向が認められた。今後，環境改善を進めていくためには，住民の関心を高めることが不可欠と考えられる。The Hannoogawa River in the western part of central Saijo town, Higashi-Hiroshima City, is a concrete-lined stream flowing north to south. To clarify its current environmental state and identify challenges for future environmental improvement, we surveyed the water quality, aquatic animals, and the local residents’ awareness of the stream. The biochemical oxygen demand of the stream water ranged between 1.1 and 3.7 mg L-1, indicating that the water was moderately polluted. However, several aquatic species that prefer oligotrophic water were recorded in a trap survey. An awareness questionnaire survey showed that newer residents who had moved to the area within the last 10 years tended to have little interest in the stream environment as compared with the responses of older residents. The results suggest a need for social outreach to increase residents’ awareness of the stream and thus fulfil the requirements for environmental improvements

Temporal and spatial fluctuations of populations of the freshwater snail Kawanina (Semisulcospira libertina) in streams: A survey using the “Kawanina trap”

カワニナを個体サイズや底質に関わらず採取できるトラップを作成し，それを用いて広島県東広島市を流れる二つの小河川を対象に，カワニナ個体群の時空間的変動に及ぼす環境要因について検討を行った。半自然河川の角脇川にトラップを仕掛け，5月～ 11月の経時変化を調べたところ，採取された個体数は期間を通じ地点により大きく異なっていた。この差は，水温や流速，BOD，pH では説明できず，河床材料との関係も明瞭ではなかったが，礫質の地点では個体数変動が少なく，殻径3mm未満の稚貝が多く捕獲された。コンクリート三面護岸化された半尾川では，角脇川に比べ非常に少数のカワニナしか捕獲されず，稚貝も1匹しか捕獲されなかったため，ほとんど繁殖が行われていないと考えられた。カワニナの生息に適した環境を評価するためには，個体サイズを考慮した調査を行うことが重要であり，本調査で用いたようなトラップは有効な手段となりうると思われる。This study aimed to elucidate the environmental factors that determine spatiotemporal fluctuations of populations of the freshwater snail Kawanina (Semisulcospira libertina) in two streams in Higashi-Hiroshima City based on a field survey using a trap designed for sampling regardless of the individual snail size or sediment. The changes from May to November in the semi-natural stream Kadowakigawa were investigated, and the number of individual snails captured by traps varied greatly depending on the site throughout the period. Differences in the numbers of captured snails could not be explained by differences in water temperature, water flow, BOD, pH, or riverbed materials between sites. However, the number of snails tended to be stable, and small individuals (< 3 mm) were frequently captured in the site with a stony riverbed. In the Hannogawa, a concrete-lined stream, only a very small number of Kawanina were captured by the trap compared to the Kadowakigawa, and only one young snail was captured by the trap during the investigation period, so the snail reproduction in this stream was considered to be unsuccessful. Quantitative studies considering the size structure of the population are important in assessing the suitability of a stream for the habitat of the snail. The “Kawanina trap” can be a useful tool for such research

Behavior of snow monkeys hunting fish to survive winter

Japanese macaques, Macaca fuscata, of Kamikochi in the Japanese Alps endure one of the coldest and harshest environments during winter when scarcity of food puts them at risk. However, various behaviors have evolved to mitigate potential mortality. These macaques typically eat bamboo leaves and the bark of woody plants in winter, but our previous study using the feces of Japanese macaques collected in the winter and DNA metabarcoding analysis revealed conclusively for the first time consumption of riverine benthos and brown trout. In this paper, we investigate how Japanese macaques hunt fish and collect these riverine biota by extensively observing their behavior, including the use of infrared sensor cameras. Many researchers have tracked Japanese macaques as part of behavioral and ecological studies, but previously the techniques by which Japanese macaques capture swimming fish has not been documented. Herein, for the first time we consider how novel macaque foraging behavior traits have evolved to secure valuable animal protein for winter survival when food resources are scarce

Long-term outcome of islet transplantation on insulin-dependent diabetes mellitus: An observational cohort study

Aims/Introduction: Among 619 patients diagnosed as insulin‐dependent diabetes mellitus or type 1 diabetes at Kyoto University, Kyoto, Japan, seven patients were selected as the ITx group and 26 age‐matched patients with no endogenous insulin secretion were selected as the MDI/CSII group. Hemoglobin A1c, aspartate aminotransferase/alanine aminotransferase (AST/ALT) and creatinine were assessed retrospectively at 1, 2, 5 and 10 years for both groups; serum C‐peptide immunoreactivity was assessed for the ITx group. Major clinical events were also assessed. Results: Hemoglobin A1c improvement in ITx was significant at 1 year (8.4% [7.8–9.9%] at baseline to 7.1% [6.3–7.4%] in ITx vs 8.2% [7.4–9.8%] at baseline to 8.1% [7.3–9.5%] in MDI/CSII, P < 0.01 between groups), and was maintained at 2 years (7.4% [6.3–8.2%] vs 8.4% [7.4–9.6%], P = 0.11). The increase of stimulated C‐peptide immunoreactivity was significant at 1 year (0.57 ng/mL [0.26–0.99 ng/mL], P < 0.05 from baseline) and 2 years (0.43 ng/mL [0.19–0.67 ng/mL], P < 0.05), although it became insignificant thereafter. There was no significant difference in AST/ALT or creatinine at 10 years, although a transient AST/ALT elevation was observed in ITx. In regard to clinical events, the occurrence of severe hypoglycemia was 14% vs 31% (relative risk 0.46, P = 0.64), that of infectious disease was 43% vs 12% (relative risk 3.71, P = 0.09) and digestive symptoms was 43% vs 7.7% (relative risk 5.57, P = 0.05) in ITx vs MDI/CSII, respectively. No patient died in either group. Conclusions: The present findings showed that ITx was considered to contribute to the reduction of hypoglycemia and better glycemic control with tolerable, but attention‐requiring, risks over a period of 10 years compared with MDI/CSII

A unique profile of insulin antibody titer in islet‐transplanted patients

Insulin antibodies (IAs) can cause glycemic variability. Islet transplantation (ITx) is a treatment for insulin-deficient diabetes that aims to establish on-target glycemic control in the absence of hypoglycemia. To date, there has not been a detailed case study of the association between ITx and IA levels. In this study, we identified a unique profile of IA titers, which differed from glutamic acid decarboxylase antibody titers, in four ITx patients. IA levels decreased with intensified immunosuppressive therapy, whereas glutamic acid decarboxylase antibodies increased transiently after ITx. These data suggest the possibility that IAs, unlike other islet autoantibodies, were eliminated due to immunosuppression after transplantation therapy. The disappearance of IAs, as well as the restoration of regulated insulin secretion after ITx, might have a positive effect on glycemic control in recipients with diabetes. Furthermore, this unique feature is suggestive of immunological pathogenesis and has implications for the treatment of IA-causing disease conditions

Recommendations for burns care in mass casualty incidents: WHO Emergency Medical Teams Technical Working Group on Burns (WHO TWGB) 2017-2020

Health and logistical needs in emergencies have been well recognised. The last 7 years has witnessed improved professionalisation and standardisation of care for disaster affected communities – led in part by the World Health Organisation Emergency Medical Team (EMT) initiative. Mass casualty incidents (MCIs) resulting in burn injuries present unique challenges. Burn management benefits from specialist skills, expert knowledge, and timely availability of specialist resources. With burn MCIs occurring globally, and wide variance in existing burn care capacity, the need to strengthen burn care capability is evident. Although some high-income countries have well-established disaster management plans, including burn specific plans, many do not – the majority of countries where burn mass casualty events occur are without such established plans. Developing globally relevant recommendations is a first step in addressing this deficit and increasing preparedness to deal with such disasters. Global burn experts were invited to a succession of Technical Working Group on burns (TWGB) meetings to: 1) review literature on burn care in MCIs; and 2) define and agree on recommendations for burn care in MCIs. The resulting 22 recommendations provide a framework to guide national and international specialist burn teams and health facilities to support delivery of safe care and improved outcomes to burn patients in MCIs.publishedVersio

Reduced glycemic variability and flexible graft function after islet transplantation: A case report

To date, studies of patients with islet transplantation addressing intermittently scanned continuous glucose monitoring profile and the flexibility of the graft islet function under different doses of insulin administration, both of which reflect the real daily life of patients, are quite limited. Here, we report a case of a 46‐year‐old woman who received islet transplantation after kidney transplantation. The patient was followed up over a period of 2 years after initial islet transplantation. Our results show that intermittently scanned continuous glucose monitoring can be useful for monitoring the reduction of glycemic variability, and suggest the appropriate regulation of insulin secretion from graft islets during mixed‐meal test by using different doses of exogenous insulin administration. Additionally, during the 2‐year observational period, glucagon elevation was detected only at hypoglycemia, whereas the level was within the normal range at normoglycemia or hyperglycemia