Drinking water temperature around the globe : understanding, policies, challenges and opportunities

Water temperature is often monitored at water sources and treatment works; however, there is limited monitoring of the water temperature in the drinking water distribution system (DWDS), despite a known impact on physical, chemical and microbial reactions which impact water quality. A key parameter influencing drinking water temperature is soil temperature, which is influenced by the urban heat island effects. This paper provides critique and comprehensive summary of the current knowledge, policies and challenges regarding drinking water temperature research and presents the findings from a survey of international stakeholders. Knowledge gaps as well as challenges and opportunities for monitoring and research are identified. The conclusion of the study is that temperature in the DWDS is an emerging concern in various countries regardless of the water source and treatment, climate conditions, or network characteristics such as topology, pipe material or diameter. More research is needed, especially to determine (i) the effect of higher temperatures, (ii) a legislative limit on temperature and (iii) measures to comply with this limit

Dealing with uncertainty in calibration of a stormwater biofilter model

Uncertainty is a part of every modelling process and is caused by many different sources. Therefore, good and reliable model predictions are often very hard to obtain. Stormwater biofilter models are no exception. For a modeler to reduce uncertainty, first it is necessary to map and understand all the sources of uncertainty and their impact on the modelling processes. This paper is focused on understanding and reduction of uncertainties during calibration process of a model for prediction of treatment efficiency of stormwater biofilters (bioretentions and raingardens). The model was applied to Monash Car Park Biofilter, to simulate removal of atrazine for which removal performance data have been available over 6 simulated storm tests. The model was first calibrated, and then sensitivity analysis has been carried out for the most sensitive model parameters. The results show the key sources of uncertainties and links between them. The predictive uncertainty intervals were constructed, suggesting that the developed model is sound

Синтез и анализ многомерных математических моделей популяционной динамики

The designing of multidimensional models of population dynamics taking into account the relations of competition and mutualism is described. The model examples in threedimensional and four-dimensional cases are considered, qualitative and numerical investigation of deterministic models is carried out. The transition to the corresponding multidimensional nondeterministic models defined by differential inclusions, fuzzy and stochastic differential equations is made, and stability analysis is performed. The structure of multidimensional stochastic models with competition and mutualism is described. The comparative analysis of deterministic and stochastic models is carried out.Описано построение многомерных моделей динамики популяций, учитывающих отношения конкуренции и мутуализма. Рассмотрены модельные примеры в трехмерном и четырехмерном случаях, проведено качественное и численное исследование детерминированных моделей. Выполнен переход к соответствующим многомерным недетерминированным моделям, задаваемым с помощью дифференциальных включений, нечетких и стохастических дифференциальных уравнений, и проведен анализ устойчивости. Описана структура многомерных стохастических моделей с конкуренцией и мутуализмом. Проведен сравнительный анализ детерминированных и стохастических моделей

The Generalized Algorithms of Global Parametric Optimization and Stochastization for Dynamical Models of Interconnected Populations

We consider the issue of synthesis and analysis of multidimensional controlled model with consideration of predator-prey interaction and taking into account migration flows, and propose new formulations of corresponding optimal control problems. In search for optimal trajectories, we develop a generalized algorithm of global parametric optimization, which is based on the development of algorithm for generating control function and on modifications of classical numerical methods for solving differential equations. We present the results of the search for optimal trajectories and control functions generation. Additionally, we propose an algorithm for the transition to stochastic controlled models based on the development of a method for constructing self-consistent stochastic models. The tool software as a part of a software package for modeling controlled dynamical systems has been developed. We have also carried out a computer study of the constructed models. The results can be used in the problems of modeling dynamics processes, taking into account the requirements of control and optimization. © 2020, Springer Nature Switzerland AG

Universal adhesives and non-carious cervical lesions. A systematic review and meta-analysis

OBJECTIVES The prevalence of non-carious cervical lesions (NCCLs) is considered to be nearly 50% on the world level, with older populations being more severely affected. NCCLs can cause both esthetical and functional problems. Universal adhesives are the latest generation of adhesive systems which, according to the manufacturers’ instruc­tions, can be used in various adhesive strategies: Etch-and-rinse (EAR), self-etch (SE) and selective-enamel-etch (SEE). The purpose of this paper was to answer the following PICOS question: “Is the risk of retention loss and post-operative sensitivity (POS) equal for EAR and SE appro­ach when restoring NCCLs with universal adhesives and composite restorations?”. MATERIALS AND METHODS A comprehensive literature search was performed with no lan­guage and date restriction throu­gh PubMed, Scopus and Web of Science. Cochrane Risk of Bias Tool was used to assess the risk of bias. Meta-analyses were performed using RevMan; fixed-effects models were applied, and heterogeneity was tested using the I2 index. The significan­ce level was set at p <0.05. RESULTS AND CONCLUSIONS The initial search yielded with 244 papers and after applying exclusion criteria 22 papers were included in qualitative, while 14 papers were included in the quantitative synthesis. Overall, the reviewed studies had no major problems regarding the study design and reporting of results. There was a statistically significant difference for the outcome retention at 6 (p = 0.02; RR = 0.53, [0.3, 0.94]),12 (p = 0.005; RR = 0.22, 95% CI [0.08, 0.63]) and 18/24 (p = 0.0002; RR = 0.32, 95% CI [0.17, 0.58]) months follow-up between the two adhesive strategies, indicating that the risk for retention loss was hi­gher in SE approach. The chance for baseline POS occurrence was higher when universal adhesives were used in EAR compared to SE mode (p = 0.008; RR = 2.05, 95% CI [1.21, 3.48]). Data from 12 and 18/24 months follow up were not heteroge­neous (I2 = 0%), while the data from 6 and 36 months (chi2 test, p = 0.02, I2 = 63%; chi2 test, p = 0.13, I2=56%, re­spectively) follow-up showed substantial heterogeneity. The results of this systematic review suggest that using uni­versal adhesives in EAR strategy can provide more favorable retention compared to SE approach up to 2 years of follow-up. The baseline POS was more likely to occur in EAR adhesive strategy. CLINICAL SIGNIFICANCE The choice of adhesive stra­tegy influences the clinical behavior of composite restorations placed with universal adhesives in NCCLs. Using universal adhesives in EAR strategy can cause post-operative sensitivity and initial patients’ discomfort, however, it provides more predictable retention compared to SE approach

Le Grand écho du Nord de la France

09 janvier 19031903/01/09 (A85,N9).Appartient à l’ensemble documentaire : NordPdeC