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Groundwater quality management is a priority in arid and semi-arid zones where water is scarce. Leachate from open dumping of municipal solid wastes may threaten groundwater quality. This research aimed at assessing groundwater quality of the aquifer of Shur river basin in Tehran province, Iran. The pollution potential of leachate from a landfill, located at the center of the basin, was estimated to assess its impact on the aquifer. Samples from 38 wells and 2 leachate ponds around the landfill were analyzed for their physico-chemical parameters and heavy metals. Leachate Pollution Index (LPI) and Water Quality Index (WQI) were calculated and multivariate statistical techniques were employed through geostatistical models to predict the spatial variability of groundwater quality and assess its contamination sources. The groundwater quality map was developed by GIS Interface. LPI indicated that leachate from the closed cell (LPI = 36) was more contaminating than that of the active site (LPI = 25). Kriging and cokriging geostatistical interpolation methods were applied to groundwater quality parameters. The best interpolation model was then identified through cross-validation with RMSE and GSD criteria. Cokriging yielded more accurate results than kriging. Spatial distribution maps showed high groundwater contamination and degraded water quality mainly in the central part of the basin, where the landfill was. Also, 293.7 ha of the study area possessed poor and very poor water quality, unsuitable for drinking. This study implicated multiple approaches for groundwater quality assessment and estimated its spatial structure as an effort toward effective groundwater quality management in Shur river basin.

Background The emergence of carbapenem-resistant Enterobacterales (CRE) continues to threaten public health due to limited therapeutic options. In the current study the incidence of carbapenem resistance among the 104 clinical isolates of Escherichia coli and the genomic features of carbapenem resistant isolates were investigated. Methods The susceptibility to imipenem, tigecycline and colistin was tested by broth dilution method. Susceptibility to other classes of antimicrobials was examined by disk diffusion test. The presence of blaOXA-48, blaKPC, blaNDM, and blaVIM carbapenemase genes was examined by PCR. Molecular characteristics of carbapenem resistant isolates were further investigated by whole-genome sequencing (WGS) using Illumina and Nanopore platforms. Results Four isolates (3.8%) revealed imipenem MIC of ≥32 mg/L and positive results for modified carbapenem inactivation method and categorized as carbapenem resistant E. coli (CREC). Colistin, nitrofurantoin, fosfomycin, and tigecycline were the most active agents against all isolates (total susceptibility rate of 99, 99, 96 and 95.2% respectively) with the last three compounds being found as the most active antimicrobials for carbapenem resistant isolates (susceptibility rate of 100%). According to Multilocus Sequence Type (MLST) analysis the 4 CREC isolates belonged to ST167 (n = 2), ST361 (n = 1) and ST648 (n = 1). NDM was detected in all CREC isolates (NDM-1 (n = 1) and NMD-5 (n = 3)) among which one isolate co-harbored NDM-5 and OXA-181 carbapenemases. WGS further detected blaCTX-M-15, blaCMY-145, blaCMY-42 and blaTEM-1 (with different frequencies) among CREC isolates. Co-occurrence of NDM-type carbapenemase and 16S rRNA methyltransferase RmtB and RmtC was found in two isolates belonging to ST167 and ST648. A colistin-carbapenem resistant isolate which was mcr-negative, revealed various amino acid substitutions in PmrB, PmrD and PhoPQ proteins. Conclusion About 1.9% of E. coli isolates studied here were resistant to imipenem, colistin and/or amikacin which raises the concern about the outbreaks of difficult-to-treat infection by these emerging superbugs in the future.

In this study, the impact of MSW landfill on the surface and groundwater resources pollution in Tehran Province was investigated using a multivariate statistical technique concerning multiple water quality indicators. To assess the role of the landfill on surface and groundwater pollution, a statistical approach was designed in a way that the distance from landfill was considered as the main factor while sub-factors were various physicochemical parameters of water samples collected from groundwater and surface water. Sampling took place for two years on a monthly basis. Results of groundwater samples indicated that SO42− (254 mg/l), PO43− (0.13 mg/l) and EC (1177.9 µs/cm) exceeded their acceptable limits of drinking water standard in near the landfill. For groundwater, all water quality parameters (except heavy metals, PO43−, SO42−, Na + , Mg2+, and pH) were higher adjacent to the landfill, than upstream and downstream locations (significance level P

In this paper we have considered an efficient adapted Unscented Kalman Filter based target tracking in directional wireless sensor networks while observations are noise-corrupted. In directional sensor networks, sensors are able to observe the target only in specified (and certainly changeable) directions. Also, sensor nodes are capable of measuring the bearings (relative angle to the target). To make target tracking efficient, first, we use scheduling algorithm which determines the sensor nodes activity. Also coverage is a challenge that we will discuss in this paper as well. Sensor nodes activation algorithm directly affects the target areas coverage. Second, we use time series to predict the motion of the target. Using ARIMA, in each step of target position estimation, an area will be predicted where the target would be there with high probability. Third, we use a version of UKF, which is adjusted to the requirements of the target tracking application, to determine the position of the target with desired precision. Fourth, a routing algorithm called as C-RPL is used to perform the communications between sensor nodes in each step. Simulation results approve that the proposed efficient target tracking algorithm achieves its goals.

This paper describes an application of a multi-objective optimization algorithm (i.e., the non-dominated sorting genetic algorithm II [NSGA-II]) and a fuzzy expert system (FES) to allocate municipal waste capacities to recycling, aerobic composting, incinerator, and landfill facilities with these objectives: (1) minimization of the economic cost; and (2) minimization of the environmental cost of the municipal solid waste management system. The non-dominated sorting genetic algorithm II is used to find multi-objective solutions, and a FES is employed for the environmental cost evaluation. Tehran, the capital of Iran, is selected as the case study. In the proposed model, the quantitative and qualitative aspects of the municipal solid waste management issue are taken into account so that the economic and environmental objectives that typically arise in cities in this regard can be considered. To achieve economic and environmental cost objectives, five scenarios with different economic and environmental costs and four solid waste management methods (recycling, aerobic composting, incinerator, and landfill) are employed. The results show that while hybrid methods for municipal waste management can be used, recycling and aerobic composting are the principal methods—that is, the scenarios that utilized higher percentages of these methods resulted in the lowest economic and environmental costs. Additionally, the results of model validation using predicted and real data from the different scenarios demonstrate the high accuracy of the proposed model.

The objective of the present work is to investigate the nonlinear vibrations of the rotating asymmetrical nano-shafts by considering surface effect. In order to compute the surface stress tensor, the surface elasticity theory is used. The governing nonlinear equations of motion are obtained with the aid of variational approach. Bubnov–Galerkin is a very effective method for exploiting the reduced-order model of the equations of motion. The averaging method is employed to analyze the reduced-order model of the system. For this purpose, the well-known Van der Pol transformation in the complex form and angle-action transformation are utilized. The effect of surface stress on the forward and backward speeds, steady state responses of the system, fixed points, close orbits and stability of the solutions is examined. The preliminary results of the research show that the absolute values of forward and backward whirling speeds in the presence of surface effect with positive residual surface stress are higher than those of regarding the system without surface effect and in the presence of surface effect with negative residual surface stress. In addition, it is seen that the undamped rotating asymmetrical nano-shaft, for specified value of detuning parameter, in the absence or presence of surface effect has various number of stable and unstable periodic solutions. Besides, there is different number of separatrix (homoclinic orbit type). Furthermore, bifurcations, number of solutions and their stability for damped rotating asymmetrical nano-shaft are investigated. Also, the above results have been obtained for rotating symmetrical nano-shaft.

Tooth development is widely used for age estimation and staging physical maturity. It is of great importance in dental age estimation in forensic dentistry, orthodontic treatment planning, and pediatric endocrinology. This study aimed to compare the accuracy of two age estimation methods, i.e., the London Atlas and Smith's method, using the panoramic view of developing teeth. In this descriptive-analytic study, panoramic radiographs of 339 healthy individuals, including 145 boys and 194 girls, were assessed. The participants aged between 5.00 and 15.99 years. Dental age of the subjects was determined by the London Atlas of Human Tooth Development and Eruption and Smith's method. The collected information was entered in the SPSS software (Ver.18). Differences and correlations between chronological and dental age were assessed by paired t tests and Pearson's correlation analysis. In all analyzes, the significance level was considered less than 0.05. The mean chronological age of the subjects was 10.13 ± 2.92 years. The mean ages estimated by the London Atlas and Smith's method were 10.29 ± 2.91 and 9.89 ± 2.84 years, respectively. Paired t test showed that the differences between the mean chronological age and mean estimated ages using the London Atlas and Smith's method were not significant (P = 0.15 and 0.16, respectively). Our findings showed that both methods had high accuracy for age estimation, but the London Atlas is easier to use.

Wireless sensor networks (WSNs) are employed in a variety of applications. One of the key applications of WSNs, which gained much attention, is the target tracking. Directional sensor networks (DSNs) are a subset of WSNs with some unique characteristics. Since optimizing the tracking system under the energy and coverage constraints in DSNs is of paramount importance, in this paper, we introduce a reliable algorithm for tracking mobile targets using directional WSNs. First, by selecting a minimum set of boundary and borderline sensor nodes, we achieve the desired coverage for an incoming detection. Second, for both deterministic ordered and random node deployments, we propose an efficient mechanism for determining the minimal interior sensor nodes that should be activated. Doing so, the network lifetime can be maximized by the employment of much fewer sensor nodes. Third, we use a geometric method for collecting data using two active sensors at a time. Accordingly, target position is estimated using the extended Kalman filter (EKF). Finally, we compare the proposed algorithm with a genetic algorithm and present the comparative simulation results of the EKF and the random walk. The results demonstrate the effectiveness of our proposed scheme in terms of the energy efficiency, coverage, and tracking accuracy.

“Environmental issues” along with raising awareness of people about the value of ecological systems and the growth of environmentalism have affected businesses systems and models by introducing new concepts and models for business such as sustainable business model . European Foundation for Quality Management (EFQM) Excellence Model provides a clear path for a company to follow in order to achieve its planned results which can be called sustainable business. The purpose of this study is to explore whether the mentioned model is suitable for the businesses that are based on cleaner production and sustainable business models. The method used in this study is an explorative one based on the literature review and exploration of the adaptability of EFQM Excellence Model (2013), including its fundamental concepts and its criteria, to eight archetypes of sustainable business. The results showed that out of eight fundamental concepts of this model, four are aligned with sustainable business model and four need redefining. Moreover, it was found that environmentalism should be added to the five enablers of the model, and results criteria of it needed to be restructured and redefined. In conclusion, it was shown that despite adoptability of the fundamental concepts of EFQM Excellence Model, there were some lacking criteria for adapting them to sustainable business model. Having this in mind, a modified type of model with the new defined criteria was proposed in this study.

The experts of the construction and civil engineering companies are responsible for selecting an appropriate supplier. Evaluation and selection of appropriate suppliers may decrease quality deficiency, cost overrun, environmental problems and etc. In this research a decision support system is developed to select appropriate supplier for construction and civil engineering companies. The effective criteria on the supplier selection process have been investigated and accommodated to internal structure of the Iranian construction and civil engineering companies by questionnaire survey. For this purpose, the current research carries out among logistics managers of the first grade Iranian construction and civil engineering companies or those with having ISO certification. After completion of questionnaires, the effectiveness of criteria is evaluated using t-student test. Five criteria are excluded, and 18 criteria are selected as effective criteria. To select appropriate supplier, the AHP and ANP approaches are utilized simultaneously. Since, these two methods use a limited number of criteria, it is essential to prioritize criteria. So, Friedman test is applied and finally five of the most important criteria have been employed. Unfortunately environmental issues are not attended by construction and civil engineering companies. To illustrate concept and performance of proposed decision support system three candidate suppliers are ranked using AHP and ANP models. Although the final results of AHP and ANP methods are the similar, the values of variation between suppliers are different. Therefore, it is recommended to employ the ANP method considering internal relations between criteria.

Using DNA as programmable, sequence specific ‘glues’, shape-controlled hydrogel units are self-assembled into prescribed structures. Here we report that aggregates are produced using hydrogel cubes with edge length ranging from 30 micrometers to 1 millimeter, demonstrating assembly across scales. In a simple one-pot agitation reaction, 25 dimers are constructed in parallel from 50 distinct hydrogel cube species, demonstrating highly multiplexed assembly. Using hydrogel cuboids displaying face-specific DNA glues, diverse structures are achieved in aqueous and in interfacial agitation systems. These include dimers, extended chains, and open network structures in an aqueous system; and dimers, chains of fixed length, T-junctions, and square shapes in the interfacial system, demonstrating the versatility of the assembly system.