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The decarbonisation and the transformation of existing District Heating (DH) systems requires high investments. For the DH utilities the implementation must take place during ongoing operation, while ensuring security of supply. In this context, it is becoming increasingly important to know the remaining service life of DH pipes when developing transformation strategies and planning the future DH systems. The pipelines of the heating networks in Germany are designed for a minimum service life of 30 years and can be operated even longer, depending on the pipe system and operational conditions. The remaining service life of buried preinsulated bonded pipes is carried out using material testing according to EN 253 (2018) combined with calculating material’s fatigue according to EN 13941-1 (2018) and AGFW FW 401 (2007). In this research work the remaining service life of four sections of preinsulated pipes in the DH network in Duisburg is determined comparing the results of material testing with the calculations of material’s fatigue. Besides the material tests according to EN 253 (2018), thermogravimetric analysis (TGA) and the apparent activation energy determined from TGA is used to estimate the remaining service life of the rigid polyurethane foam (PUR). For the pipes investigated, the service life is determined by the decrease in the properties of the PUR. The results imply that sections can be operated for another 6 up to 14 years and reach a service life of remarkable 50 years under local conditions. Status assessment and the remaining service life of DH pipes are a key element of DH utilities transformation strategies. In order to gain reliable results there is a need to improve knowledge on determining the remaining service life. The TGA is a promising approach for improving the PUR’s service life analysis especially since the previously valid methods of the old EN 253 have been withdrawn. The described approach using current standards and improved new methods in the field will accelerate the use of research results to DH utilities.

Heavy metal accumulation in agriculture soils is of particular concern in China, while the status and probabilistic health risks of metal contamination in Chinese agriculture soils have been rarely studied at the national scale. In this study, we compiled a database of heavy metal concentrations in Chinese agriculture soils and selected six heavy metals for pollution assessment and risk screening: arsenic (As), cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb) and Zinc (Zn). Monte Carlo simulation was employed to assess the probabilistic health risks, the associated uncertainties, as well as variations in toxicity parameters, ingestion rate and body weight. Results indicated that the concentrations of Cd were elevated above their reference standard and Cd had the highest mean geo-accumulation index (Igeo) of 1.79. Moreover, the mean hazard index (HI) through exposure to six heavy metals was 1.85E−01 and 2.87E−02 for children and adults, respectively, with 2.2% of non-cancer risks for children that exceeded the guideline value of 1. In contrast, 95.0% and 90.0% of the total cancer risks (TCR) through exposure to six heavy metals for children and adults, respectively, exceeded the guideline value of 1E−06. Six metals were ranked based on their percent of risk outputs exceeding the guideline values. Arsenic had the high exceedance of both cancer and non-cancer risks, while both Cr and Cd were metals with high concern that had high exceedance of cancer risk. Sensitivity analyses indicated that metal concentrations and ingestion rate of soil were the predominant contributors to total risk variance. Overall, the adverse health risks induced by exposure to heavy metals contaminated farmland were elevated. Results from this study may provide valuable implications for public health professionals and policy-makers to design effective strategy to manage nation-wide farmland and reduce heavy metal exposure. Keywords: Agriculture soil, Heavy metal, Probabilistic risk, Monte Carlo simulation, Risk level ranking

Understanding how biotic indicators respond to natural variability is essential for the health stateevaluationofthebenthicecosystems.Thisstudyanalysedthecompositionandstructureofthebenthiccommunities in the coastal lagoon Stagno Longu of Posada (Sardinia) to investigate the seasonalresponse of the biological indicator M-AMBI. Multivariate analysis and biodiversity descriptors showedtemporal (winter–summer) and spatial variability (across the three basins of the lagoon).The ecological status (ES) of Stagno Longu was assessed using M-AMBI index: results mainlyshowed the lagoon to be in ‘‘good’’ and ‘‘moderate’’ status across seasons and basins, while ‘‘poor’’status was recorded in the North basin during summer.Despite the absence of direct human pressures, sediment organic content (OC) varied seasonallyand spatially and M-AMBI revealed winter to summer shifts on the ES of 3 out of 6 sampling stations.Overall, this study reveals negative significative correlation on the variations on M-AMBI with theincrease of sediment OC across the studied sites, none the less discrepancies on the ES of certainstations were detected causing over/underestimation.Results suggested that natural seasonal variability is a relevant factor to be considered whileperforming ES assessments and implementing monitoring programmes in Mediterranean transitionalecosystems when applying indicators such as M-AMBI. Interreg V-A Italy-France Maritime 2014-2020 Cooperation Program info:eu-repo/semantics/publishedVersion

We present a status assessment of the Hawaiian islands dry forests, including the current status, stressors, and future viability. Dry forests generally have relatively low rainfall and are found on the leeward sides of the islands in lowland or in montane-subalpine zones. Historically, dry forests were located on all of the main Hawaiian islands and currently they are still found there. However, the quality of these forests is largely composed of a mix of native/nonnative vegetation. In addition to the native lowland and montane-subalpine dry forests that characterized dry forests historically, introduced dry forests and tree plantations are now classified as dry forests. Our assessment of dry forest viability, defined as the likelihood of persistence over the long term, is based on the conservation biology concepts of representation, redundancy, and resiliency. The main stressors to dry forests are invasive ungulates, plants, other herbivores, wildfires; drought; and agriculture and human development. Ongoing conservation efforts help to protect remnant patches of dry forests but this depends largely on combined efforts of various stakeholders. We developed four plausible future scenarios, each differing in levels of natural resource management, to evaluate the status of dry forests into the foreseeable future. Two of the scenarios, which are based on no change in conservation actions (Scenario One; status quo) and a slight increase in conservation actions (Scenario Two) have the highest likelihood of occurring in the foreseeable future while the other two, which are based on a slight to moderate decrease in conservation actions (Scenario Three) and a moderate to large increase in conservation actions (Scenario Four) do not. Scenario Three would severely degrade and fragment native dry forest and result in reduced resiliency, redundancy, and representation. In Scenario Four, the substantial improvements in restoration of native dry forests would result in increased resiliency, redundancy, and representation.

Accurate fluid management in patients admitted to the intensive care unit (ICU) is still one of the most challenging and important tasks for critical care physicians. Despite the incredible development of technology applied to medicine, the correct assessment of hydration status in critically ill patients is still complex. Studies from literature have reported prevalence of fluid overload (FO) between 62% and 64.8%; it is widely accepted that FO is associated with adverse outcomes and increased mortality in ICU patients. The gold standard method, isotope dilution, is impractical and mostly unavailable in clinical settings. Therefore critical care physicians should rely on other methods to classify patients according to fluid balance to prevent worse outcomes and diminish mortality. Noninvasive methods such as physical examination, fluid balance recording, and chest radiography are widely available, but their use can lead to inaccurate data and misled decisions, especially when used alone. Other noninvasive methods such as bioimpedance and diverse ultrasonography techniques have demonstrated their diagnostic value. The information provided by these methods has been correlated correctly with fluid status. The concomitant use of diverse noninvasive methods could be the best approach to correct fluid status assessment.

The total annual nitrogen (N) input into cropping systems increased by 62%, but N in harvestable output (kg N ha–1 year–1) increased only by 42% in India during 1990–2009. The relationship between input and output of N in cropping systems translates into a regularly decreasing trend of N use efficiency and the need to substantially improve the fertilizer management practices. Around 70% of the total fertilizer N applied in India is used for production of food grains. There is an evolutionary trend in the way fertilizer N has been managed in cereals. Since 1960s, fertilizer N has generally been managed by following blanket recommendations consisting of two or three preset split applications of the total amount of N. However, in recent decades emphasis is shifting toward achieving high agronomic efficiency by following strategies revolving around feeding the crop N needs. Technological developments have made it possible to quickly and nondestructively quantify spectral characteristics of leaves, which can then be used to diagnose plant N deficiency and, indirectly, to correct N fertilization in real time and site-specific manner leading to improved N use efficiency. Nitrogen status assessment tools, however, must be affordable.