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The global increase of antimicrobial resistance (AMR) is a major public health concern. An effective AMR surveillance tool is needed to track the emergence and spread of AMR. Wastewater surveillance has been proposed as a resource-efficient tool for monitoring AMR carriage in the community. Here, we performed genomic surveillance of antimicrobial-resistantEscherichia coliobtained from fecal sludge and sewage in Uganda to gain insights intoE. coliepidemiology and AMR burden in the underlying population. Selective media containing different antibiotic combinations (cefotaxime, ciprofloxacin, cefotaxime + ciprofloxacin + gentamicin) were used to obtain antimicrobial-resistantE. colifrom fecal sludge and sewage. Short-read sequencing was performed for the obtained isolates, and a subset of isolates (selected from predominant sequence types (STs)) was also subjected to long-read sequencing. Genomic analysis of the obtainedE. coliisolates (n = 181) revealed the prevalence of ST10 complex, including ST167 (n = 43), ST10 (n = 28), ST1284 (n = 17), and ST617 (n = 4), in both fecal sludge and sewage, irrespective of antibiotics used for selection. We also detected global high-risk clones ST1193 (n = 10) and ST131 (n = 2 clade A, n = 3 subclade C1-M27, and n = 1 subclade C2). Diverse AMR determinants, including extended-spectrum β-lactamase genes (mostlyblaCTX-M-15) and mutations ingyrAandparC, were identified. Analysis of the completed genomes revealed that diverse IncF plasmids and chromosomal integration were the major contributors to the spread of AMR genes in the predominant STs. This study showed that a combination of sewage surveillance (or fecal sludge surveillance) and whole-genome sequencing can be a powerful tool for monitoring AMR carriage in the underlying population.

Material flow analysis (MFA) is an effective tool for waste management, but low- and middle-income countries lack essential data for MFA. This study proposed a simplified MFA (sMFA) utilizing local expert judgment (LEJ) and examining the impact of simplification on its uncertainty. A stochastic sMFA model was developed for nitrogen and phosphorus in urban Mandalay, Myanmar. This model was compared with the intensive MFA (iMFA) model employing intensive surveys for primary data collection. For the total loadings to the environment, the medians of the sMFA were higher by 3% and 11%, respectively, for nitrogen and phosphorus than those of the iMFA. The widths of the 80% confidence intervals of these loadings in the sMFA, normalized by those in the iMFA, were − 0.05 and − 0.11, respectively. The three largest flows to the environment were the same for the two models: on-site sanitation effluent/leakage, greywater, and industrial wastewater. Large median gaps between the models were observed for industrial wastewater, fecal sludge, and human excreta, associated with informal waste management, whereby LEJ did not work well. Overall, the sMFA demonstrated a good estimation of nitrogen and phosphorus flows with limited increase of uncertainty, still requiring focused attention on informal waste streams. Graphical abstract

Seasonal and gender impacts have not been well considered in fecal exposure assessment, especially in low- and middle-income countries. This study examined the seasonal and gender impacts on fecal exposure trends in children through daily living activities in an urban slum in Bangladesh. We determined Escherichia coli concentrations in seven types of environmental samples (n = 232) and the activity data of children via diary recording, questionnaires, and interview surveys. Daily and monthly exposures were stochastically estimated for drinking, eating, pond bathing, well bathing, and hand-to-mouth contact. Of the five pathways, pond bathing and drinking contributed a large part of the daily and monthly exposure. Significant seasonal differences were observed in daily exposures for bathing, which were higher in the rainy season (2.59 × 102 CFU/day for boys and 6.19 × 10−1 CFU/day for girls) than in the dry season (1.69 × 102; 4.30 × 10−2), because of longer pond bathing time and more contaminated bathing water in the rainy season. In contrast, eating had significantly higher exposure in the dry season (3.71 × 10; 3.22 × 10) than the rainy season (1.50 × 10; 1.24 × 10) due to the higher dish contamination. Significantly higher daily exposure was observed in the bathing for boys than girls, as boys spent longer time for bathing at a heavily contaminated pond. HIGHLIGHTS Seasonal and gender impacts on fecal exposure were studied in a slum in Bangladesh.; Escherichia coli levels of seven types of samples and activity data of children were collected.; Fecal exposure of children through five pathways was modeled by seasons and gender.; Drinking predominantly contributed to the exposure of girls regardless of seasons.; Boys’ preference to pond bathing caused the largest exposure in the rainy season.

On-site wastewater treatment plants (OSTs) often lack monitoring, resulting in unreliable treatment performance. They thus appear to be a stopgap solution despite their potential contribution to circular water management. Low-maintenance but inaccurate soft sensors are emerging that address this concern. However, how their inaccuracy impacts the catchment-wide treatment performance of a system of many OSTs has not been quantified. We develop a stochastic model to estimate catchment-wide OST performances with a Monte Carlo simulation. In our study, soft sensors with a 70% accuracy improved the treatment performance from 66% of the time functional to 98%. Soft sensors optimized for specificity, indicating the true negative rate, improve the system performance, while sensors optimized for sensitivity, indicating the true positive rate, quantify the treatment performance more accurately. This new insight leads us to suggest programming two soft sensors in practical settings with the same hardware sensor data as input: one soft sensor geared to high specificity for maintenance scheduling and one geared to high sensitivity for performance quantification. Our findings suggest that a maintenance strategy combining inaccurate sensors with appropriate alarm management can vastly improve the mean catchment-wide treatment performance of a system of OSTs.

Ascertaining peak oxygen demand is crucial for plant designers to determine blower capacities of wastewater treatment plants in planning phase. To obtain this technical information without cumbersome influent sampling and analysis, a set of field-test activated sludge reactors equipped with DO and nitrate-N sensors was installed at 3 sites and continuously operated for a couple of months in each field. Under the controlled aeration and hydraulics of the reactors, the hourly influent oxygen demands were back-calculated as biodegradable constituents using the IWA-Activated Sludge Model #1. The daily maximum concentrations (rounded to last for 1-hour) of biodegradable organics and nitrogen were ranged between 45~258 mg-COD/L and 10.4~32.3 mg-N/L in Site #1; 119~244 mg-COD/L and 28.3~38.7 mg-N/L in Site #2; 194~552 mg-COD/L and 30.2~51.7 mg-N/L in Site #3 respectively. The marginal blower capacities to maintain at least 1.0 mg-O2/L of DO in the daily maximum oxygen demand were estimated based on the datasets using the statistical method, Extreme Value Distribution analysis. To maintain the DO concentration for 99 days out of 100 days of the plant operations, the blower capacity was supposed to be designed as high as 1.4~2.2 times than those of the blower calculated from the daily average concentration.

Septic systems are potentially a significant source of greenhouse gases (GHGs). The present study investigated GHGs from the blackwater septic systems that are widely used especially in low- and middle-income countries. Ten blackwater septic tanks in Hanoi, Vietnam, were investigated using the floating chamber method. The average methane and carbon dioxide emission rates measured at the first compartment (65% of total capacity) of the septic tanks were 11.92 and 20.24 g/cap/day, respectively, whereas nitrous oxide emission was negligible. Methane emission rate was significantly correlated with septage oxidation-reduction potential (ORP) (R = -0.67, p = 0.034), chemical oxygen demand mass (R = 0.78, p = 0.007), and biochemical oxygen demand mass (R = 0.78, p = 0.008), whereas it was not significantly correlated with water temperature (R = 0.26, p = 0.47) and dissolved oxygen (R = -0.59, p = 0.075) within the limited range: 30.6-31.7 °C and 0.03-0.34 mg-O2/L. The methane emission rates from septic tanks accumulating septage for >5 years were significantly higher than those at 0-5 years (p = 0.016). These results suggest that lower ORP and higher biodegradable carbon mass, in association with longer septage storage periods are key conditions for methane emissions. To the best of our knowledge, this is the first study to characterize GHG emissions from septic systems.

High levels of microbial fecal pollution are a major concern in many countries. A human-associated genetic marker for Escherichia coli (H8) has recently been developed for fecal source tracking. The assessment of the H8 marker performance is crucial before it can be applied as a suitable method for fecal source tracking in each country. The performance (specificity and sensitivity) of the H8 marker was evaluated by using non-target host groups (cattle, buffalo, chicken, duck, and pig feces) and target host groups (influent and effluent from a wastewater treatment plant and septages). SYBR based real-time PCR (polymerase chain reaction) was done on 400 E. coli isolates from non-target and target host groups after E. coli isolation. It was found that the specificity from animal feces samples collected in Thailand was 96%. Moreover, influent, effluent, and septage samples showed the values of the sensitivity at 18, 12, and 36%, respectively. All of the non-target host groups were found to be significantly different with positive proportions from the target host group (septage samples) (p ≤ 0.01). Based on the results, this marker is recommended for use as a human-associated E. coli marker for identifying sources of fecal pollution in Thailand.

Global challenges of water scarcity and food insecurity justify sanitation approaches that utilize dry sanitation with the agricultural use of excreta. One such approach is urine-diverting dry toilets (UDDTs) that separate urine and feces at the source at the time of excretion, thereby efficiently sanitizing the feces without liquid by separating the urine. However, in practice, some people have an aversion to the agricultural use of human excreta. Although the resource value of human excreta can potentially drive the spread of sanitation, this can only be achieved when a sanitation system utilizing human excreta for agriculture is accepted and rooted in society. This chapter studies the long-term acceptability of UDDTs that were installed several years ago in Vietnam, Malawi, and Bangladesh, focusing on the fertilizer value of human excreta. The majority of UDDTs were continuously used in all cases. Physical conditions and usability were the primary reasons to use UDDTs. Proportions of the continuous use of urine were low in all cases, and the perceived fertilizer values of urine by UDDT users were significantly lower than those of feces in Malawi. The fertilizer values of feces and urine alone were not always a motivation to use UDDTs although that of feces possibly contributed to the continuous use of UDDTs in Malawi. Religious impurity was a major barrier to use of urine and feces in Bangladesh, although it could be overcome with clean conditions of UDDTs and appropriate socio-cultural context.

Sustainable Development Goals (SDGs) present a new vision to establish an adequate and equitable sanitation system and require more consideration on the basis of the socio-cultural aspects of global sanitation. Despite these directions, the establishment of global sanitation in low- and middle-income countries has been challenging, and the socio-cultural aspects, especially the interconnections of socio-culture with materials and health, are overlooked. In this context, an interdisciplinary approach including humanities and social sciences is necessary based on the understanding that sanitation is embedded in society. In terms of the interconnection between socio-culture and materials, sanitation requires social relations to function its service chain, and in the interconnections between socio-culture and health, the risk of health by inadequate sanitation is socially allocated unevenly. In other words, an adequate and equitable sanitation system involves appropriate interconnections between the three components of sanitation (social-culture, health, and materials). Therefore, this chapter presents the concept of the “Sanitation Triangle” as an interdisciplinary framework by focusing on the relationship between the three elements.

Sanitation can change the fate of excreta and control the emission to the living and ambient environment, leading to the reduction of fecal exposure and the mitigation of fecal–oral infectious risk. The fate of excreta and its associated health risks in sanitation, however, may not be limited within the living boundary of a single person or even within a community. Based on examples in Vietnam, this chapter demonstrates the transfer of health risks in sanitation and its allocation in society. Along a river, fecal pollutants and the associated health risks were transferred from the urban upstream areas to rural downstream areas, resulting in the change of livelihood downstream. Resource-oriented sanitation was enabled at the expense of female farmers’ health risks through their handling of fecal matter, indicating a gender-related risk allocation. This chapter also discusses the health risk allocation of modern sewerages between those who flush excreta and those who work in the sewerages, and that of on-site sanitation along the sanitation service chain. Since sanitation possibly causes the transfer of health risks in society, sound social allocation and mitigation of health risks are essential to address social challenges in sanitation.

The function of sanitation is to control the fate of human waste. A toilet is only the entrance to sanitation, and human waste as materials need to be appropriately handled throughout a sanitation service chain to control the impact of human waste on the environment. While the toilet has a private aspect, post-toilet sanitation has a public aspect. It is unclear how individuals and society should share the impact of post-toilet sanitation. Sanitation enabling the use of human waste may have greater material, socio-cultural, and health impacts in society than sanitation that does not enable the use of human waste. If the impacts caused by sanitation are unreasonable, sanitation will not be sustainable. Designing a sanitation service chain is traditionally an engineering-based business that optimizes these impacts, especially from the material and health aspects. However, in the real world, the system with the maximum benefit and minimum burden as a total for society is not necessarily preferred by all individual stakeholders. Rather than simply adjusting stakeholders’ interests, sanitation may actively establish appropriate relationships with each stakeholder, even on an individual level, to be more sustainable. Such a design approach would go beyond the traditional design approaches of sanitation optimization that use conventional engineering tools.

In the study of water, sanitation, and hygiene (WASH) and its related health impact, it is imperative to understand the people and their respective environments to ensure lasting improvements in their quality of life. To explore this theme, this chapter provides details of a Participatory action research (PAR) conducted with members of Dziko Langa, a children and youth club, based in two peri-urban settlements in Lusaka, Zambia. The study was aimed at collaborative examination and intervention alongside club members, focusing on health and sociocultural aspects relating to WASH within their communities. The chapter is divided into three parts: (1) peri-urban WASH assessment and intervention through participatory approaches, (2) development of a quantitative self-assessment methodology for fecal contamination in their living environment, and (3) visualization approaches for community and stakeholder engagement. Through collaborative studies such as these, we can further explore the abilities of local communities to independently measure the health levels of their environment, identify WASH priorities, engage with stakeholders and policymakers, and share their findings for the betterment of the broader community.

On-site wastewater treatment plants (OSTs) are widely seen as a stopgap solution, mainly because of a lack of monitoring and the resulting unreliable treatment performance. To address this concern, low maintenance, but inaccurate soft sensors are emerging. However, the impact of this inaccuracy on the treatment performance of entire fleets of OSTs has not been quantified. We develop a stochastic model to estimate these performances. In the modelled case soft sensors with a 70% accuracy improve the treatment performance from 66% (percentage of time functional) to 98%. Soft sensors optimised for specificity (true negative rate) improve the system performance, while such optimised for sensitivity (true positive rate) quantify the treatment performance more accurately. Based on this new insight we suggest to build two soft sensors with the same data input in practical settings: one soft sensor geared towards high specificity, for maintenance scheduling, and one geared towards high sensitivity, for fleet performance quantification. The findings suggest that inaccurate sensors in combination with an appropriate alarm management have the potential to largely improve the treatment performance of a fleet of OSTs. We present a management strategy to reduce undetected failures drastically and thereby diminish negative impacts on environmental and human health.

Globally, 2.8 billion people use on-site sanitation facilities, which need regular emptying of accumulated fecal sludge. Illegal dumping from informal emptying businesses, one of the major challenges in environmental management, is widely observed. Considering Mandalay, Myanmar, this study aimed to determine why informal emptying businesses are selected and estimate the lost revenue for a formal emptying service provider (FP) due to the informal businesses. We interviewed 400 households on their recognition and experiences regarding emptying services and willingness-to-pay for improved service. Revenue loss was estimated by comparing the present and theoretical maximum revenues. Results showed that 91.0% of households recognized FP only. Among 134 emptying-experienced households, 32.8%, 59.7%, and 4.5% chose FP with legal contact, FP with illegal contact, and informal service providers, respectively. The service fees from FP with illegal contact did not become revenue for FP; this was a major informal emptying business in the city. Differently from previous studies, the major illegal dumping was done by FP in this area. A great financial loss was estimated that FP lost 76.5% of the theoretical maximum revenue due to informal business. Logistic regression analysis indicated people’s intention to shorten the waiting time through illegal contact, even by paying a higher fee. As emptying services are typically required immediately after fecal sludge is over-accumulated, shorter waiting times and faster contact methods were the reasons why the informal business was selected. Less bureaucratic and more customer friendly system could reduce revenue loss, charge more, and increase profits.

Diversity and productivity of primary producers are known to be influenced simultaneously by resource availability and resource ratio, but the relative importance of these two factors differed among studies and so far only entire phytoplankton communities were investigated which might ignore specific nutrient requirements and stoichiometric plasticity of different functional groups. We measured nutrient availability (DIN, total N [TN], total P [TP]), nutrient imbalance (TN:TP, DIN:TP, N:Pseston), species richness, and abundance of the whole phytoplankton community, as well as those specific for cyanobacteria, diatoms, and dinoflagellates in Cau Hai lagoon in Vietnam. We determined the correlation among these variables, using structural equation modeling. The models applied to the whole phytoplankton community indicated that the nutrient availability (particularly TP and DIN) drove variation in phytoplankton abundance and richness, and that abundance also depended on species richness. The models applied to different functional groups differed considerably from the entire community and among each other, and only a part of the models was significant. The relationship between nutrient availability (mainly TP) and abundance was driven by cyanobacteria, and the relationship between nutrient imbalance (only with N:Pseston) and species richness was driven by diatoms. Remarkably, the positive relationship between species richness and abundance, as consistently observed for the whole phytoplankton community, was only observed for one of the three functional groups (diatoms), indicating that resource complementarity occurs particularly among species of different functional groups. Our results emphasized that nutrient availability (TP and to a lesser extent DIN) as well as nutrient imbalance (albeit only with N:Pseston as proxy) were driving factors for the phytoplankton community in the Cau Hai lagoon and hence alterations in both of these factors leading to a shift in phytoplankton species composition and productivity.

The fast reactor core is composed of hundreds of core elements that self-stand on the lower support plate, and core elements does not have support to constrain vertical displacement in order to avoid effects such as thermal elongation. When an earthquake occurs, the group vibration behavior including the rising of core elements in the vertical direction, the collision with adjacent core elements in the horizontal direction, and the fluid structure interaction is observed. The three dimensional core group vibration analysis code (REVIAN-3D) for evaluating these has been constructed. In this study, to grasp and estimate the group vibration behavior with and without a core former under the earthquake motion, seismic experiment of hexagonal multi bundle model using core element mock-up was conducted. These test results show that the presence of the core former decrease the horizontal displacements and increases core compaction. And the test results are used for the verification data of the analysis code REVIAN-3D.[1]

The fast reactor core is composed of hundreds of core elements that stand independently on the core support plate, but does not have support to constrain vertical displacement in order to avoid effects such as thermal elongation. When the earthquake occurs, the group vibration behavior is shown, including the rising of core elements in vertical direction, the collision with adjacent core elements in horizontal direction, and the fluid structure interaction. The three dimensional core group vibration analysis code (REVIAN-3D) was constructed to evaluate them. In the case of fast reactor cores in Japan, the horizontal displacement of core elements at the outermost periphery is restricted by the core former (core barrel). However, since there is no core former in fast reactors other than Japan and the boundary conditions are different from those in Japan, the vibration behavior also differs. In this study, to grasp and estimate the group vibration behavior with and without a core former under the earthquake motion, seismic experiment of hexagonal multi bundle model using core assembly mock-up was conducted [1]. These test results show that the horizontal displacements are larger and impact force between pads of core assembly mock-up is smaller without the core former. In this paper, the analysis was verified by group vibration tests with and without a core former.

Submersed macrophytes are key elements of shallow coastal ecosystems but globally declined due to anthropogenic disturbances and climate change. Foliar elemental and isotopic compositions of macrophytes are being increasingly used to identify nutritional status and environmental conditions including potential stress factors, thereto insight is required in its interspecific variation. In this paper, we present interspecific variations in foliar nutrients (C, N, P) and stable isotopes (δ13C and δ15N) of four macrophyte species (Najas indica, Halophila beccarii, Halodule uninervis, Halophila ovalis) in Cau Hai lagoon (Vietnam) in relation to key environmental variables. The foliar C, N, δ13C and δ15N values varied among species and related to salinity, water depth and/or DIN concentrations. Foliar N and C:N values were correlated to DIN concentration in the water (N. indica and H. beccarii, respectively), whereas foliar C:P was correlated to P concentrations in sediment (N. indica) or water depth (H. uninervis).Foliar δ13C of H. beccarii and H. uninervis increased with salinity and δ15N of N. indica with both salinity and DIN concentration in the water. These aquatic plants likely varied either in resource acquisition strategies (e.g. uptake of CO2 or HCO3 –, N and P from different sources) or in their usage (e.g. C investment in structural tissue) and in their response to changes in salinity, water depth and DIN concentration in the water. The studied macrophytes likely experienced relatively high N and P availability and another factor than P or N probably inhibited C-fixation and/or carbon storage of these plants.

Infectious disease transmission is frequently mediated by the environment, where people's movements through and interactions with the environment dictate risks of infection and/or illness. Capturing these interactions, and quantifying their importance, offers important insights into effective interventions. In this study, we capture high time-resolution activity data for twenty-five Vietnamese farmers during collection and land application of human excreta for agriculture. Although human excreta use improves productivity, the use increases risks of enteric infections for both farmers and end users. In our study, the activity data are integrated with environmental microbial sampling data into a stochastic-mechanistic simulation of E. coli contamination on hands and E. coli ingested. Results from the study include frequent and variable contact rates for farmers' hands (from 34 to 1344 objects contacted per hour per hand), including highly variable hand-to-mouth contact rates (from 0 to 9 contacts per hour per hand). The frequency of hand-to-mouth contacts was substantially lower than the widely-used frequency previously reported for U.S. Office Workers. Environmental microbial contamination data highlighted ubiquitous E. coli contamination in the environment, including excreta, hands, toilet pit, handheld tools, soils, surfaces, and water. Results from the simulation suggest dynamic changes in E. coli contamination on hands, and wide variation in hand contamination and E. coli ingested amongst the farmers studied. Sensitivity analysis suggests that E. coli contamination on hands and ingested doses are most influenced by contamination of handheld tools, excreta, and the toilet pit as well as by frequency of hand-to-mouth contacts. The study findings are especially relevant given the context: no farmers reported adequate storage time of human excreta, and personal protective mask availability did not prevent hand-to-mouth contacts. Integrating high time-resolution activity data into exposure assessments highlights variation in exposures amongst farmers, and offers greater insight into effective interventions and their potential impacts. (C) 2018 The Authors. Published by Elsevier B.V.

This study investigated the occurrence of Escherichia coli pathotypes in sanitary wastewater and drinking water in a Bangladeshi urban slum and the potential associations between these sources. We examined 621 E. coli isolates from sanitary wastewater and stored drinking water by multiplex PCR and dual-index sequencing, classifying them into eight pathotypes based on 14 virulence genes and additionally evaluating the possession of the human-specific E. coli genetic biomarker H8. The proportions of pathogenic E. coli were significantly different (P

Currently, antimicrobial drugs are not eliminated during the wastewater treatment process, especially in developing countries where antimicrobial drugs are used with less controls. An increase in contamination from effluent entering river systems is a major contributor to antimicrobial drug resistance and the spread of antimicrobial-resistant genes throughout rivers. This study aims to investigate the occurrence of antimicrobial-resistant Escherichia coli (E. coli) and evaluate the impact of urbanization on the distribution of antimicrobial-resistant E. coli along the lower part of the Chao Phraya River in Thailand. It was found that the geometric mean E. coli concentration was 624 CFU/100 mL. In addition, the geometric mean concentrations of E. coli resistant to cefotaxime and ciprofloxacin were 86 and 182 CFU/ 100 mL, respectively. A positive correlation coefficient was found between the concentration of antimicrobial-resistant E. coli and the number of population. The concentrations of E. coli were significantly positively correlated with antimicrobial-resistant E. coli (R = 0.950, P < 0.001). Therefore, this study indicated that antimicrobial-resistant E. coli were widely distributed in the Chao Phraya River with the highest concentrations in the Bangkok metropolitan area. These populations have been linked to an increase in antimicrobial-resistant E. coli contamination.

Launched in 2014, Japan-France collaboration on the ASTRID (Advanced Sodium Technological Reactor for Industrial Demonstration) project is active both in reactor design and in R&D fields. CEA, Framatome, JAEA, MHI and MFBR are in charge of this collaboration. In the design field, Japan-France evaluates core assemblies with interferences on seismic events. The objectives of this collaboration are to determine the core assembly lattice displacements under seismic load in order to demonstrate the safe behavior of the core regarding control rod insertion, structural integrity, and reactivity variation, etc. From this point of view, the object of this study is to verify the seismic evaluation method on core assemblies between Japan and France by comparing the results. Using their evaluation method applied to common the ASTRID core input data, Japan and France will calculate a collision load, a horizontal displacement, and a vertical displacement for core assemblies. As the first step of this work, the comparison of each evaluation (modelling and calculation results) is carried out considering the horizontal seismic excitation and without including the vertical component. The analysis of this benchmark calculation shows a satisfactory agreement between the Japanese and French tools and the figures show a good behavior of the core in horizontal direction under French seismic condition. This paper describes the summary of horizontal seismic analysis comparison and the future analysis plan.

This study aimed to determine the relative potency of direct ischemic preconditioning (DIPC) and remote ischemic preconditioning (RIPC) for protection against ischemic spinal cord injury in rabbits and to explore the mechanisms involved. In experiment 1, we compared the neurological and histopathological outcomes of DIPC, kidney RIPC, and limb RIPC. The DIPC and kidney RIPC groups received two cycles of 5-min occlusion/15-min reperfusion of the abdominal aorta and left renal artery, respectively. The limb RIPC group received two cycles of 10-min occlusion/10-min reperfusion of the femoral arteries bilaterally. Thirty minutes after the conditioning ischemia, spinal cord ischemia was produced by occluding the abdominal aorta for 15 min. In experiments 2 and 3, we investigated whether pretreatment using a free-radical scavenger, dimethylthiourea (DMTU), an adenosine A1 receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), or a mitochondrial ATP-sensitive potassium channel antagonist, 5-hydroxydecanoate (5HD), could attenuate the protective effects of DIPC. In experiment 4, comprehensive analysis of phosphorylated proteins in the spinal cord was performed using a Proteome Profiler Array followed by immunoblotting to elucidate the signal pathway activated by DIPC. In experiment 1, DIPC improved the neurological and histopathological outcomes, whereas kidney and limb RIPC had no protective effects. In experiments 2 and 3, strong protective effects of DIPC were reconfirmed but were not attenuated by DMTU, DPCPX, or 5HD. In experiment 4, DIPC induced phosphorylation of Akt2. DIPC, but not kidney or limb RIPC, protected against ischemic spinal cord injury in rabbits. Akt2 might contribute to this protective effect.

Dewatering of faecal sludge (FS) is indispensable for adequate FS management. However, comprehensive knowledge is lacking on FS dewatering performance. This study compared the dewatering performance of FS from different countries and onsite sanitation technologies, to assess influential characteristics on dewatering, and to compare dewatering performance of FS with wastewater sludge. We collected 73 FS samples from septic tanks, lined pit latrines, unlined pit latrines and johkasou tanks in Uganda, Vietnam and Japan, and 18 samples of wastewater sludge in Switzerland. Capillary suction time (CST) and total solids (TS) of centrifuged sludge (%TSfinal) were determined as metrics of dewatering rate and dewaterability, respectively, together with relevant sludge characteristics. Data were analysed by bootstrapping comparison of median results of each sample category and by bootstrapping multiple regression analysis to quantify the relative importance of sludge characteristics on dewatering performance. Results showed that the dewatering rate was significantly different between FS from different technologies, whereas dewaterability was significantly different within the same technology. FS had a significantly lower dewatering rate than wastewater sludge. In contrast, FS dewaterability was greater than wastewater sludge. However, this could be attributed to higher concentrations of sand in FS. Electrochemical properties such as NH4-N and surface charge had the strongest correlation to dewatering rate, and solid properties such as sand content and total volatile solids to dewaterability. The results identify potential characteristics that could explain and predict the high variability of FS dewatering performance that is observed in the field.

Low back pain (LBP) is the most common cause of chronic pain. Numerous clinical scales are available for evaluating pain, but their objective criteria in the management of LBP patients remain unclear. This study aimed to determine an objective cutoff value for a change in the Pain Intensity Numerical Rating Scale (ΔPI-NRS) three months after LBP treatment. Its utility was compared with changes in six commonly used clinical scales in LBP patients: Pain Disability Assessment Scale (PDAS), Pain Self-Efficacy Questionnaire (PSEC), Pain Catastrophizing Scale (PCS), Athens Insomnia Scale (AIS), EuroQoL 5 Dimension (EQ5D), and Locomo 25. We included 161 LBP patients treated in two representative pain management centers. Patients were partitioned into two groups based on patient’s global impression of change (PGIC) three months after treatment: satisfied (PGIC = 1, 2) and unsatisfied (3–7). Multivariate logistic regression analysis was performed to explore relevant scales in distinguishing the two groups. We found ΔPI-NRS to be most closely associated with PGIC status regardless of pre-treatment pain intensity, followed by ΔEQ5D, ΔPDAS, ΔPSEC, and ΔPCS. The ΔPI-NRS cutoff value for distinguishing the PGIC status was determined by ROC analysis to be 1.3–1.8 depending on pre-treatment PI-NRS, which was rounded up to ΔPI-NRS = 2 for general use. Spearman’s correlation coefficient revealed close relationships between ΔPI-NRS and the six other clinical scales. Therefore, we determined cutoff values of these scales in distinguishing the status of ΔPI-NRS≥2 vs. ΔPI-NRS

To design fast reactor (FR) core components, seismic response must be evaluated in order to ensure structural integrity. Thus, a core seismic analysis method has been developed to evaluate 3D core vibration behavior considering fluid structure interaction and vertical displacements (rising). The analysis code is verified by a series of vibration tests. The evaluation model to simulate the influence of core element deformation due to heat and irradiation were developed and the analysis of the seismic test was performed. And the evaluation model was verified by comparing the seismic test and analysis results. A fast reactor core consists of hundreds of core elements, which lengthen due to thermal expansion and swelling. So, the core elements are self-standing on the core support structure and not restrained in the axial direction. When the vertical seismic excitation surpasses gravitational acceleration, it is necessary to consider vertical displacements and horizontal displacements of the core elements simultaneously. This 3-D vibration behavior is affected by the fluid loads from ambient coolant and the interference of surrounding structures. To solve this, the influential factors to vibration behaviors due to the structure and fluid body, including fluid structure interaction, are extracted and the 3-D reactor core group vibration analysis code (REVIAN-3D) is developed. Core elements are deformed due to thermal expansion and irradiation, and are interfered with surrounding elements each other. The interference increases the frictional force acting on the core element and reduce the vertical displacement (rising) of the core element during the earthquake. To evaluate this reduction of rising, the evaluation model simulating this deformation is incorporated in REVIAN-3D. In this study, the analysis of the vibration test was carried out using the new incorporated evaluation model. As the deformation of mock-up increases, the vertical displacement (rising) decreases, and when the initial interference due to deformation exceeds the threshold, no rising occurs. This trend agreed well between the vibration test and analysis. It is verified that the new incorporated evaluation model simulates the test result enough.

Core elements of a fast reactor are self-standing on the core support structure and not restrained in the axial direction. When the earthquake occurs, it is necessary to consider vertical behavior and horizontal displacement of the core elements simultaneously. In the core seismic analysis, a three dimensional core vibration behavior was evaluated by considering fluid structure interaction, collision with adjacent core elements and vertical displacement and verified by a series of vibration tests. But the evaluation had a assumption of straightness of each core elements which may be bowed due to thermal expansion and swelling under restraint of the horizontal direction between the upper pad and lower structure (Entrance Nozzle). If the core elements are deformed in its plant operation, they may push each other against its adjacent core elements. The large horizontal interference forces may work to decrease the vertical displacement of the core elements. In this study, to grasp and estimate the behavior under the deformed core elements under the earthquake motion, a three dimensional seismic analysis model consist of all of core elements with consideration of the effect of deformed core elements were prepared, analyzed and verified by hexagonal-matrix tests with 37 core elements and single row mock-up models with 7 core elements. These test results show that the rising displacements decrease with increased deformation and no rising occurs when the deformations exceed a threshold. In this paper, the effect of bending deformation due to thermal expansion and swelling on the rising displacement of the core elements was shown by seismic experiments.

While the prevalence of supernumerary teeth (ST) is high in permanent dentition, the etiology of ST in humans remains unclear. However, multiple murine models of ST have elaborated on dated mechanisms traditionally ascribed to ST etiology: one involves the rescue of rudimental teeth, and the second considers the contribution of odontogenic epithelial stem cells. It remains unclear whether these mechanisms of ST formation in mice are applicable to humans. The third dentition is usually regressed apoptotic—that is, the teeth do not completely form in humans. Recently, it was suggested that ST result from the rescue of regression of the third dentition in humans. The present investigation evaluates the proportion of collected general ST cases that evinced a third dentition based on the clinical definition of ST derived from the third dentition. We also investigated the contribution of SOX2-positive odontogenic epithelial stem cells to ST formation in humans. We collected 215 general ST cases from 15,008 patients. We confirmed that the general characteristics of the collected ST cases were similar to the results from previous reports. Of the 215 cases, we narrowed our analysis to the 78 patients who had received a computed tomography scan. The frequency of ST considered to have been derived from the third dentition was 26 out of 78 cases. Evidence of a third dentition was especially apparent in the premolar region, was more common in men, and was more likely among patients with ≥3 ST. SOX2-positive odontogenic epithelial stem cells within the surrounding epithelial cells of developing ST were observed in non–third dentition cases and not in third dentition cases. In conclusion, the third dentition is the main cause of ST in humans. The odontogenic epithelial stem cells may contribute to ST formation in cases not caused by a third dentition.

Globally, the challenge of handwashing with soap (HWWS) still exists despite the importance of HWWS being shown previously. This study aimed to evaluate faecal contamination on the hands of children and to find factors related to faecal contamination from handwashing techniques, HWWS, knowledge and awareness of water, sanitation, and hygiene (WASH), and a comprehensive WASH index.The study was conducted at two elementary schools with 169 children in a densely populated area of Bandung, Indonesia. The survey involved handwashing observation using a checklist, hand bacteria sampling and questionnaires.Most children (98.7%) had faecal contamination. Girls had significantly fewer Escherichia coli than boys (P 0.05). Ability in handwashing techniques, HWWS, and knowledge and awareness of WASH were poor in the lower grades. Escherichia coli counts were negatively correlated with handwashing technique (r = -0.171, P 0.05), HWWS (r = -0.225, P 0.01) and the WASH index (r = -0.205, P 0.05).Proper handwashing technique and HWWS at appropriate times can reduce faecal contamination. Moreover, it is important that both grade-based and gender-based handwashing education be considered in elementary school education.A l’échelle mondiale, le défi du lavage des mains au savon (HWWS) existe toujours, en dépit de l'importance révélée de ce procédé. Cette étude visait à évaluer la contamination fécale sur les mains des enfants et à trouver des facteurs liés à la contamination fécale résultant des procédés de lavage des mains, du lavage des mains au savon, de la connaissance et de la sensibilisation à l'eau, aux sanitaires et à l'hygiène (WASH), ainsi qu'un indice WASH détaillé. MÉTHODES: L’étude a été menée dans deux écoles élémentaires avec 169 enfants dans une zone densément peuplée de Bandung, en Indonésie. L'enquête comprenait l'observation du lavage des mains à l'aide d'une liste de contrôle, un échantillonnage bactérien sur les mains et des questionnaires. RÉSULTATS: La plupart des enfants (98,7%) avaient une contamination fécale. Escherichia coli était nettement moins présent chez les filles que chez les garçons (p0,05). L'aptitude dans les techniques de lavage des mains, le lavage des mains au savon, ainsi que la connaissance et la sensibilisation au WASH étaient faibles dans les classes inférieures. Les comptages d’E. Coli corrélaient négativement avec la technique de lavage des mains (r = -0,171 ; p0,05), le lavage des mains au savon (r = 0,225 ; p0,01) et l'indice WASH (r= - 0,205 ; p0,05).Une technique de lavage des mains appropriée et un lavage des mains au savon à des moments opportuns peuvent réduire la contamination fécale. De plus, il est important de prendre en compte l’éducation au lavage des mains basée sur le niveau et le sexe dans l'enseignement primaire.