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Introduction Nonocclusive mesenteric ischemia (NOMI) has been reported to be associated with high mortality. Early diagnosis of NOMI and prompt restoration of the intestinal blood flow is necessary in order to achieve a favorable outcome. Presentation of case We present the case of a patient who developed NOMI after autologous blood collection and was treated by selective infusion of the superior mesenteric artery with papaverine, intestinal decompression using a long intestinal tube, the administration of antibiotics, and fluid replacement. Although this non-surgical management was successful, 8 weeks after the ischemic event, segmental bowel resection was necessary because of repeated intestinal obstruction caused by bowel stricture. Discussion Autologous blood collection might be a risk factor of NOMI. In addition, the possibility of delayed intestinal stenosis remains, even if bowel necrosis and surgical resection were avoided with non-surgical management including vasodilator therapy. Conclusion Rapid diagnosis and intervention are essential to minimize intestinal ischemia. [ABSTRACT FROM AUTHOR]

Highlights • Reduction en masse is feasible in abdominal pain after inguinal hernia reduction. • Laparoscopic relief could be an efficient therapeutic option. • Modified Kugel Patch repair with neck of hernia sac ligation is recommended. Abstract Introduction Reduction en masse is a rare complication of inguinal hernia. This condition is defined as the displacement of a strangulated hernia mass into the preperitoneal space. Case presentation A 62-year-old man presented with severe abdominal pain after a forcible reduction of an incarcerated right inguinal hernia. Abdominal computed tomography (CT) scan suggested strangulated bowel. Emergency exploratory laparoscopy was performed and the incarcerated bowel was successfully released. Elective preperitoneal inguinal hernia repair using the Modified Kugel™ Patch was performed under laparoscopic guidance. The patient made an uneventful recovery. Discussion Reduction en masse should be considered when abdominal pain persists after a difficult reduction of inguinal hernia. Laparoscopic guidance led to the definitive repair of the inguinal hernia with reduction en masse. Conclusion Laparoscopic relief can be an efficient therapeutic option for the management of this condition. In addition, Modified Kugel™ Patch repair with ligation of the hernia sac could be a reasonable treatment. [ABSTRACT FROM AUTHOR]

Abstract: Landfill sites are emerging in climate change scenarios as a significant source of greenhouse gases. The compacted final soil cover at landfill sites plays a vital role for the emission, fate and transport of landfill gases. This study investigated the effects of dry bulk density, ρb , and particle size fraction on the main soil–gas transport parameters – soil–gas diffusivity (Dp /Do , ratio of gas diffusion coefficients in soil and free air) and air permeability (ka ) – under variably-saturated moisture conditions. Soil samples were prepared by three different compaction methods (Standard and Modified Proctor compaction, and hand compaction) with resulting ρb values ranging from 1.40 to 2.10gcm−3. Results showed that Dp and ka values for the ‘+gravel’ fraction (<35mm) became larger than for the ‘−gravel’ fraction (<2mm) under variably-saturated conditions for a given soil–air content (ε), likely due to enhanced gas diffusion and advection through less tortuous, large-pore networks. The effect of dry bulk density on Dp and ka was most pronounced for the ‘+gravel’ fraction. Normalized ratios were introduced for all soil–gas parameters: (i) for gas diffusivity Dp /Df , the ratio of measured Dp to Dp in total porosity (f), (ii) for air permeability ka /ka ,pF4.1, the ratio of measured ka to ka at 1235kPa matric potential (=pF 4.1), and (iii) for soil–air content, the ratio of soil–air content (ε) to total porosity (f) (air saturation). Based on the normalized parameters, predictive power-law models for Dp (ε/f) and ka (ε/f) models were developed based on a single parameter (water blockage factor M for Dp and P for ka ). The water blockage factors, M and P, were found to be linearly correlated to ρb values, and the effects of dry bulk density on Dp and ka for both ‘+gravel’ and ‘−gravel’ fractions were well accounted for by the new models. [Copyright &y& Elsevier]

Highlights • We apply a model based on concepts from percolation theory (PT) and the effective-medium approximation (EMA) to better understand diffusion and permeability. • Comparison with experiments measured in packings of angular and rounded sand grains as well as glass beads shows model capabilities. • Results indicate that the effect of pore-throat size distribution on gas diffusion and permeability was minimal in these sand and glass bead packs. Abstract Understanding gas transport in porous media and its mechanism has broad applications in various research areas, such as carbon sequestration in deep saline aquifers and gas explorations in reservoir rocks. Gas transport is mainly controlled by pore space geometrical and morphological characteristics. In this study, we apply a physically-based model developed using concepts from percolation theory (PT) and the effective-medium approximation (EMA) to better understand diffusion and permeability of gas in packings of angular and rounded sand grains as well as glass beads. Two average sizes of grain i.e., 0.3 and 0.5 mm were used to pack sands in a column of 6 cm height and 4.9 cm diameter so that the total porosity of all packs was near 0.4. Water content, gas-filled porosity (also known as gas content), gas diffusion, and gas permeability were measured at different capillary pressures. The X-ray computed tomography method and the 3DMA-Rock software package were applied to determine the average pore coordination number z. Results showed that both saturation-dependent diffusion and permeability of gas showed almost linear behavior at higher gas-filled porosities, while deviated substantially from linear scaling at lower gas saturations. Comparing the theory with the diffusion and permeability experiments showed that the determined value of z ranged between 2.8 and 5.3, not greatly different from X-ray computed tomography results. The obtained results clearly indicate that the effect of the pore-throat size distribution on gas diffusion and permeability was minimal in these sand and glass bead packs. [ABSTRACT FROM AUTHOR]

• Surveys were conducted to reveal characteristics of current demolition techniques. • A model of selective dismantling is proposed, and its potential is evaluated. • Current demolition is proven unsustainable, with a recycling rate as low as 3%. • Selective dismantling takes time but doubles resale value, greatly reduces disposal costs. • Selective dismantling will be competitive if higher disposal fees are put in place. In Vietnam, an increase in construction activities together with the absence of recycling-oriented demolition techniques is giving rise to an alarming generation of construction and demolition waste. This study scrutinized the current state of building demolition approaches in Hanoi, Vietnam and evaluated the potential for the selective dismantling, or deconstruction, of reinforced-concrete (RC) houses. Site observations, direct measurement, and interviews were conducted to obtain information on technical, environmental, and economic characteristics of three residential housing sites, each representing a typical current demolition technique (manual, hybrid, and mechanical demolition). A selective dismantling site is proposed based on the collected survey data and published case studies. Our findings confirmed the unsustainability of RC-building demolition practices in Hanoi, which have an average reuse/recycling rate of roughly 3%. The application of selective dismantling will boost the recycling rate to a remarkable 90%, associated with a 55% decrease in greenhouse gas emissions. Even though selective dismantling is more time-consuming and therefore more costly, it results in double the resale value and an eight-fold decrease in disposal costs. The results of a sensitivity analysis indicate that increasing the current disposal fee will significantly improve the feasibility of selective dismantling, suggesting a need for stricter disposal charging mechanisms along with other interventions such as the development of recycling facilities to promote the introduction of this building removal alternative in Vietnam. [ABSTRACT FROM AUTHOR]

• Potentials of stationary and mobile concrete recycling plants in Hanoi are evaluated. • Financial and socio-environmental costs and benefits are calculated. • Demand for recycled concrete exceeds waste concrete supply, indicating a promising market. • The stationary plant is more financially attractive than the mobile plant. • The mobile plant is viable if externalities are factored in. Increasing waste generation and the absence of a formal recycling industry are exacerbating the inadequacy of Construction and Demolition Waste (CDW) management in Hanoi, Vietnam. This study assesses potential CDW recycling in Hanoi by estimating the prospective supply of and demand for CDW recycling plants and evaluating their likely costs and benefits. Supply of concrete waste was calculated based on the weight-per-construction-area method whilst demand for recycled concrete aggregates (RCA) was determined by estimating the amount of aggregates for road construction in Hanoi from 2013 to 2017. Two potential models of CDW recycling plants were considered: a stationary plant and a mobile plant, with capacities of 1,000 and 360 tons/day, respectively. Our findings reveal that demand for RCA exceeds waste concrete supply, suggesting a promising market for RCA. Positive Net Present Value and Internal Rate of Return values of the stationary plant indicate its feasibility as an investment option. Meanwhile, the introduction of mobile recycling plants might require governmental intervention to internalize recycling positive externalities. Supporting policies might include a combination of a virgin material tax, green public procurement, and quality standard development. [ABSTRACT FROM AUTHOR]

• 15 building construction and demolition sites in Vietnam were surveyed. • Waste generation rates, composition, and flows were found at sites of varied scale. • Layout quantification, image analysis, and face-to-face interviews were conducted. • Soil, concrete, and brick were the most common waste components found. • A reuse and recycling rate of merely 10% was observed. This study conducted a survey at 15 building construction and demolition sites in Hanoi, Vietnam in order to identify waste generation rates (WGR), composition, and current handling practices of construction and demolition waste (CDW). Waste quantification based on CDW layout, image analysis to identify CDW components, and face-to-face interviews with construction and demolition contractors to reveal CDW flows were performed. WGRs of 79.3 kg/m2 and 1,030 kg/m2 were determined in small- and large-scale construction sites, respectively, whilst WGRs at small and large demolition sites were 610 kg/m2 and 318 kg/m2. The composition analysis identified soil, concrete, and brick as the major CDW components, consistent with building structures in Vietnam. The interviews discovered that merely 10% of total CDW flows was from recycled and reused CDW. Reuse and recycling rates were most significant for metal and were lower (in descending order) for brick, concrete, and soil. These findings raise a need for aggressive and integrated strategies to promote more sustainable CDW management in the country, including the development of recycled CDW product standards, policies that facilitate recycling, and more importantly, a sustainable business model for CDW recycling, for which future evaluations of economic feasibility are of great importance. [ABSTRACT FROM AUTHOR]

Global warming and urbanization together with development of subsurface infrastructures (e.g. subways, shopping complexes, sewage systems, and Ground Source Heat Pump (GSHP) systems) will likely cause a rapid increase in the temperature of relatively shallow groundwater reservoirs (subsurface thermal pollution). However, potential effects of a subsurface temperature change on groundwater quality due to changed physical, chemical, and microbial processes have received little attention. We therefore investigated changes in 34 groundwater quality parameters during a 13-month enhanced-heating period, followed by 14 months of natural or enhanced cooling in a confined marine aquifer at around 17 m depth on the Saitama University campus, Japan. A full-scale GSHP test facility consisting of a 50 m deep U-tube for circulating the heat-carrying fluid and four monitoring wells at 1, 2, 5, and 10 m from the U-tube were installed, and groundwater quality was monitored every 1–2 weeks. Rapid changes in the groundwater level in the area, especially during the summer, prevented accurate analyses of temperature effects using a single-well time series. Instead, Dual-Well Analysis (DWA) was applied, comparing variations in subsurface temperature and groundwater chemical concentrations between the thermally-disturbed well and a non-affected reference well. Using the 1 m distant well (temperature increase up to 7 °C) and the 10 m distant well (non-temperature-affected), the DWA showed an approximately linear relationships for eight components (B, Si, Li, dissolved organic carbon (DOC), Mg 2+ , NH 4 + , Na + , and K + ) during the combined 27 months of heating and cooling, suggesting changes in concentration between 4% and 31% for a temperature change of 7 °C. [ABSTRACT FROM AUTHOR]

Growing plants to facilitate life in outer space, for example on the International Space Station (ISS) or at planned deep-space human outposts on the Moon or Mars, has received much attention with regard to NASA's advanced life support system research. With the objective of in situ resource utilization to conserve energy and to limit transport costs, native materials mined on Moon or Mars are of primary interest for plant growth media in a future outpost, while terrestrial porous substrates with optimal growth media characteristics will be useful for onboard plant growth during space missions. Due to limited experimental opportunities and prohibitive costs, liquid and gas behavior in porous substrates under reduced gravity conditions has been less studied and hence remains poorly understood. Based on ground-based measurements, this study examined water retention, oxygen diffusivity and air permeability characteristics of six plant growth substrates for potential applications in space, including two terrestrial analogs for lunar and Martian soils and four particulate substrates widely used in reduced gravity experiments. To simulate reduced gravity water characteristics, the predictions for ground-based measurements (1 - g ) were scaled to two reduced gravity conditions, Martian gravity (0.38 - g ) and lunar gravity (0.16 - g ), following the observations in previous reduced gravity studies. We described the observed gas diffusivity with a recently developed model combined with a new approach that estimates the gas percolation threshold based on the pore size distribution. The model successfully captured measured data for all investigated media and demonstrated the implications of the poorly-understood shift in gas percolation threshold with improved gas percolation in reduced gravity. Finally, using a substrate-structure parameter related to the gaseous phase, we adequately described the air permeability under reduced gravity conditions. [ABSTRACT FROM AUTHOR]

Abstract: DNA repair gene alterations have been shown to cause a reduction in DNA repair capacity. We hypothesised that DNA repair gene polymorphisms may be risk factors for prostate cancer (PC). To test this hypothesis, DNA samples from 165 cases of prostate cancer and healthy controls were analyzed by PCR-RFLP to determine the genotypic frequency of three DNA repair genes (XRCC1, XPC and XRCC7). We found that the frequency of 939Gln variant at XPC Lys939Gln was significantly lower in PC cases (OR=0.39, P =0.016). Haplotype analysis of XRCC1 Arg194Trp (C/T) and Arg399Gln (G/A) revealed that the frequency of the T–A haplotype was significantly higher in PC patients. This is the first report on the studies of XPC and XRCC1 Arg194Trp polymorphisms in PC, and our present data suggest that XPC Lys939Gln and the T–A haplotype of XRCC1 Arg194Trp and Arg399Gln may be risk factors for PC in Japanese. [Copyright &y& Elsevier]

Groundwater is essential for the Earth biosphere but is often contaminated by harmful chemical compounds due to both anthropogenic and natural causes. A key factor controlling the fate of harmful chemicals in groundwater is the reduction/oxidation (redox) conditions. The formation factors for the groundwater redox conditions are insufficiently understood. In this study, long-term groundwater quality beneath one of the world megacities was monitored and evaluated. We measured and compared hydrogeochemical conditions including groundwater quality (35 chemical parameters) and redox conditions of five aquifers in the Arakawa Lowland and Musashino Upland, southern Kanto Plain of the Tokyo Metropolitan area, Japan. Monitoring results suggested the following: The main origin of groundwater is precipitation in both the Lowland and Upland areas. The three aquifers in the Arakawa Lowland are likely fully separated, with one unconfined and two confined aquifers under iron reducing and methanogenic conditions, respectively. Oppositely, in the Musashino Upland, the water masses in the two aquifers are likely partly connected, under aerobic conditions, and undergoing the same groundwater recharge and flow processes under similar hydrogeological conditions. The different groundwater redox conditions observed are likely caused by the very different groundwater residence times for the Arakawa Lowland and Musashino Upland. Unlabelled Image • Long-term groundwater quality including 35 chemical parameters was monitored. • Five aquifers in the Arakawa Lowland and Musashino Upland of Japan were targeted. • Completely different groundwater redox conditions were observed for both study areas. • Three aquifers in the Lowland were under iron reducing to methanogenic conditions. • Two aquifers in the Upland were under aerobic conditions. [ABSTRACT FROM AUTHOR]