A review of the degradation of antibiotic contaminants using advanced oxidation processes: modification and application of layered double hydroxides based materials.

In recent years, the treatment of organic pollutants has become a global concern due to the threat to human health posed by emerging contaminants, especially antibiotic contamination. Advanced oxidation processes (AOPs) can solve the organic pollution problem well, which have been identified as a promising solution for the treatment of hard-to-handle organic compounds including antibiotic contaminants. Layered double hydroxides (LDHs) are excellent catalysts because of their flexible tunability, favorable thermal stability, abundant active sites, and facile exchangeability of intercalated anions. This paper conducted a systematic review of LDHs-based materials used for common antibiotic removal by three significant AOP technologies, such as photocatalysis, the Fenton-like processes, and peroxymonosulfate catalysis. The degradation effects studied in various studies were reviewed, and the mechanisms were discussed in detail based on the type of AOPs. Finally, the challenges and the application trends of AOPs that may arise were prospected. The aim of this study is to suggest ways to provide practical guidance for the screening and improvement of LDH materials and the rational selection of AOPs to achieve efficient antibiotic degradation. This could lead to the development of more efficient and environmentally friendly materials and processes for degrading antibiotics, with significant implications for our ecological conservation by addressing water pollution.

Peroxymonosulfate activation by CuMn-LDH for the degradation of bisphenol A: Effect, mechanism, and pathway.

The remediation of water contaminated with bisphenol A (BPA) has gained significant attention. In this study, a hydrothermal composite activator of Cu3Mn-LDH containing coexisting phases of cupric nitrate (Cu(NO3)2) and manganous nitrate (Mn(NO3)2) was synthesized. Advanced oxidation processes were employed as an effective approach for BPA degradation, utilizing Cu3Mn-LDH as the catalyst to activate peroxymonosulfate (PMS). The synthesis of the Cu3Mn-LDH material was characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). According to the characterization data and screening experiments, Cu3Mn-LDH was selected as the best experimental material. Cu3Mn-LDH exhibits remarkable catalytic ability with PMS, demonstrating good degradation efficiency of BPA under neutral and alkaline conditions. With a PMS dosage of 0.25 g·L-1 and Cu3Mn-LDH dosage of 0.10 g·L-1, 10 mg·L-1 BPA (approximately 17.5 µM) can be completely degraded within 40 min, of which the TOC removal reached 95%. The reactive oxygen species present in the reaction system were analyzed by quenching experiments and EPR. Results showed that sulfate free radicals (SO4•-), hydroxyl free radicals (•OH), superoxide free radicals (•O2-), and nonfree radical mono-oxygen were generated, while mono-oxygen played a key role in degrading BPA. Cu3Mn-LDH exhibits excellent reproducibility, as it can still completely degrade BPA even after four consecutive cycles. The degradation intermediates of BPA were detected by GCMS, and the possible degradation pathways were reasonably predicted. This experiment proposes a nonradical degradation mechanism for BPA and analyzes the degradation pathways. It provides a new perspective for the treatment of organic pollutants in water.

Effective adsorption of Pb(ii) from wastewater using MnO2 loaded MgFe-LD(H)O composites: adsorption behavior and mechanism.

Pb(ii) adsorption by MnO2/MgFe-layered double hydroxide (MnO2/MgFe-LDH) and MnO2/MgFe-layered metal oxide (MnO2/MgFe-LDO) materials was experimentally studied in lab-scale batches for remediation property and mechanism analysis. Based on our results, the optimum adsorption capacity for Pb(ii) was achieved at the calcination temperature of 400 °C for MnO2/MgFe-LDH. Langmuir and Freundlich adsorption isotherm models, pseudo-first-order and pseudo-second-order kinetics, Elovich model, and thermodynamic studies were used for exploring the Pb(ii) adsorption mechanism of the two composites. In contrast to MnO2/MgFe-LDH, MnO2/MgFe-LDO400 °C has a stronger adsorption capacity and the Freundlich adsorption isotherm model (R2 > 0.948), the pseudo-second-order kinetic model (R2 > 0.998), and the Elovich model (R2 > 0.950) provide great fits to the experimental data, indicating that the adsorption occurs predominantly via chemisorption. The thermodynamic model suggests that MnO2/MgFe-LDO400 °C is spontaneously heat-absorbing during the adsorption process. The maximum adsorption capacity of MnO2/MgFe-LDO400 °C for Pb(ii) was 531.86 mg g-1 at a dosage of 1.0 g L-1, pH of 5.0, and temperature of 25 °C. Through characterization analysis, the main mechanisms involved in the adsorption process were precipitation action, complexation with functional groups, electrostatic attraction, cation exchange and isomorphic replacement, and memory effect. Besides, MnO2/MgFe-LDO400 °C has excellent regeneration ability in five adsorption/desorption experiments. The above results highlight the powerful adsorption capacity of MnO2/MgFe-LDO400 °C and may inspire the development of new types of nanostructured adsorbents for wastewater remediation.

Tamoxifen induced maculopathy presenting like macular telangiectasia type 2 in a patient with breast cancer.

INTRODUCTION: Drug-induced crystalline maculopathy has been reported secondary to tamoxifen use for breast cancer treatment. It could be misdiagnosed as macular telangiectasia type 2 (MacTel type 2). CASE REPORT: A 56-year-old woman with a history of diabetes mellitus and breast cancer was referred to our clinic with painless, bilateral, gradual onset of central vision loss for several months. The fundus examination showed the macular pigmentary change in both eyes and a few refractile crystalline deposits in the parafoveal area in the left eye. However, the rest of the retina was normal in both eyes. MANAGEMENT AND OUTCOME: With the diagnosis of tamoxifen-induced maculopathy, the drug was discontinued and supplementary treatment was started. DISCUSSION: In this report, patient medical and drug history was an important and powerful measure. Due to the side effects of long-term use of tamoxifen, we need further studies on the need for retinal screening in these patients.

A comprehensive review on pollution status and associated health risk assessment of human exposure to selected heavy metals in road dust across different cities of the world.

In order to expound on the present situation and potential risk of road dust heavy metals in major cities, a total of 114 literatures mainly over the past two decades, involving more than 5000 sampling sites in 61 cities of 21 countries, were screened through the collection and analysis of research papers. The concentration, sources, distribution, health risk, sample collection, and analytical methods of heavy metal research on road dust in cities around the world are summarized. The results show that Cd, Zn, and Cu in many urban road dusts in the world are higher than the grade II of the Chinese maximum allowable concentration of potentially toxic elements in the soil. Geo-accumulation index values show that Pb > Cd > Zn > Cu had the highest contamination levels. Hazard index assessment indicates Pb and Cr had the highest potential health risk, especially for children in which ingestion was found as the main exposure pathway. Moreover, through comparative analysis, it is found that some pollutants are higher in developed and industrialized cities and transport (53%) followed by industrial emissions (35%) provide the major contributions to the sources of heavy metals.

Halogenated organic pollutants (HOPs) in marine fish from the Beibu Gulf, South China Sea: Levels, distribution, and health risk assessment.

Six marine fish species, collected from the Beibu Gulf were statistically analyzed for polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), and dichlorodiphenyltrichloroethanes (DDTs). The concentrations of ∑14PBDEs, ∑26PCBs, and ∑6DDTs ranged from 11.8-1431, 8.74-495, and 9.47-1263 ng g-1 lipid weight (lw), respectively. In general, PBDEs were the predominant halogenated organic pollutants (HOPs) in the Beibu Gulf. The homologues profiles of Mugil cephalus and Trichiurus nanhaiensis differed from other four species. For example, the contributions of deca-BDEs in M. cephalus (14 %) and T. nanhaiensis (1 %) were lower than other four species (56 %). The ratio of (DDE + DDD)/ΣDDTs in all samples was >0.5, indicating that DDTs were mainly derived from historical residues. Intakes of HOPs through the consumption of the marine fish from the study areas might not subject residents of the coastal areas in the Beibu Gulf to health risks.

Enhancing mechanism of arsenic(iii) adsorption by MnO2-loaded calcined MgFe layered double hydroxide.

The use of MnO2/MgFe-layered double hydroxide (MnO2/MgFe-LDH) and MnO2/MgFe-layered double oxide (MnO2/MgFe-LDO400 °C) for arsenic immobilization from the aqueous medium is the subject of this research. Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to characterise MnO2/MgFe-LDH and MnO2/MgFe-LDO400 °C. Based on our developed method, MnO2 was spread on the clay composites' surfaces in the form of a chemical bond. The clay composite exhibited a good adsorption effect on arsenic. The experimental findings fit the pseudo-second-order model well, indicating that the chemisorption mechanism played a significant role in the adsorption process. Furthermore, the Freundlich model suited the adsorption isotherm data of all adsorbents well. The recycling experiment showed that MnO2/MgFe-LDH and MnO2/MgFe-LDO400 °C exhibited good stability and reusability. In summary, MnO2/MgFe-LDH and MnO2/MgFe-LDO400 °C are promising for developing processes for efficient control of the pollutant arsenic.

Diversity, Distribution, and Biogeography of Freshwater Fishes in Guangxi, China.

The Guangxi Zhuang Autonomous Region has the largest number of cavefish species in the world and is a global biodiversity hotspot. In this study, a species list of freshwater fishes in 12 Sub-basins of Guangxi was compiled systematically. Moreover, the species composition and distribution of the diversity were analyzed via the G-F index, taxonomic diversity index, and beta diversity index. Results showed that 380 species of freshwater fishes were recorded in this region, which belonged to 158 genera in 43 families and 17 orders in 2 phyla, in which 128 species of endemic fishes and 83 species of cavefish accounted for 33.68% and 21.84%, respectively. The species diversity from northwest to southeast gradually decreased for most Sub-basins. The G-F index has generally risen in recent years. The taxonomic diversity index showed that the freshwater fish taxonomic composition in Guangxi is uneven. The spatial turnover component was the main contributor to beta diversity. A cluster analysis showed that the 12 Sub-basins in the study area could be divided into four groups, and the phylogenetic relationships of freshwater fishes in Guangxi generally reflect the connections between water systems and geological history. The freshwater fish system in Guangxi, which belonged to the South China division in the Southeast Asiatic subregion of the Oriental region, originated in the early Tertiary period. The results will provide the information needed for freshwater fish resource protection in Guangxi and a reference for promoting the normalization of fish diversity conservation in the Pearl River Basin and other basins.

Challenges of Emergency Medical Services Response to Arasbaran Twin Earthquakes; a Content Analysis.

Introduction: One of the most important concerns in responding to disasters is providing Basic Life Support (BLS) services. Considering the key role of Emergency Medical Services (EMS) in providing BLS, the purpose of this study is to investigate the experience of provincial EMS during their response to the Arasbaran twin earthquakes and its challenges in Iran. Methods: This study was conducted using a qualitative approach and the conventional content analysis method. Data were collected through Focused Group Discussions (FGD) and semi-structured in-depth interviews with purposively-selected EMS paramedics and officials in East Azerbaijan Province, Iran. To form the main categories, the interviews were encoded in three stages and the similar codes were placed under the same subcategories and merged. Results: A total of 26 EMS paramedics participated in the study. The codes extracted from the interviews, after three stages of reduction, were placed in the top ten categories, including the lack of preparedness and coordination, dead bodies' management challenges, responders' psychosocial support, deficiencies in supplies and ambulances, difficulty of access to rural areas, volunteer management, non-documentation of the experiences, communication challenges, recalling, and deploying of EMS responders. Conclusion: Timely response of the EMS and paramedics' sense of responsibility for providing services were positive and successful points about the emergency response operations. The weaknesses of EMS should, therefore, be addressed through transferring of experiences and by planning and arranging training courses.

Evaluation of the Effect of Religious Fasting on Retinal Vessel Density and Retinal Thickness Using Optical Coherence Tomography Angiography.

We conducted this study to assess the effect of religious fasting on intraocular pressure (IOP) as well as retinal parameters and retinal thickness during Ramadan using optical coherence tomography angiography (OCTA) performed on a spectral domain device. All the participants ate a pre-dawn meal and drink, and then fasted for at least 15 hours. We assessed a total of 61 eyes from 31 healthy volunteers with a mean age of 32.87 ± 8.07. A significant decrease was found in the median IOP after fasting at 10.00 mmHg in comparison with the pre-fasting value of 12.00 mmHg (p < .0001). Retinal peri-papillary capillary (RPC) whole image, RPC inside disk, and RPC mean values showed significant decreases after fasting (p = .011, .012, and .032 respectively). RPC whole vessel density (VD), RPC inside VD, and RPC VD mean values also showed significant decreases after fasting period (p = .025, <.0001, and .003, respectively). Religious fasting during the warm season could decrease IOP. It could also reduce the blood flow of the retina, specifically the macula, and the retinal peri-papillary VD.

Argon Laser Synechiolysis for Irido-Corneal Adhesion.

Purpose: To introduce a new method for treating irido-corneal adhesion (ICA) by using argon laser. Case Presentation. A 60-year-old woman with advanced glaucoma who is undergoing trabeculectomy. In follow-up visits, choroidal effusion and iridocorneal adhesion were seen in the examination. The massive choroidal effusion was treated with medical therapy. In further follow-up examination, ICA was repaired with argon laser. Result: Early laser treatment prior to surgical management is suggested in postoperative synechia. Conclusion: Early argon laser synechiolysis is a less-invasive procedure which prevents probable surgical complications such as local detachment of Descemet's membrane or bleeding in surgical synechiolysis.

Changes in Anterior Chamber Parameters Measured by Pentacam in Coronavirus Disease 2019 Infection: A Longitudinal Study.

PURPOSE: To evaluate changes in anterior segment parameters measured by imaging in coronavirus disease 2019 (COVID-19) infection. METHODS: This longitudinal observational study included patients who recovered from COVID-19. All subjects exhibited a confirmed diagnosis of COVID-19 with a positive result of nasopharyngeal reverse transcription-polymerase chain reaction evaluation. Corneal Pentacam (Oculus, Dutenhofen, Germany) imaging was performed at least two weeks after recovery from systemic COVID-19. Measurements were repeated one and three months later. RESULTS: A total of 20 patients, 11 (55%) of whom were females, with a mean age of 35.5 ± 7.1 years (age range: 25-51 years) recovered from nonhospitalized COVID-19 infection, were enrolled in this study. An increase in the keratometry mean front, keratometry mean back, cornea volume, and anterior chamber depth was observed in the longitudinal evaluation; however, they showed no statistical significance. The anterior chamber volume was statistically increased at three-month follow-up, compared to baseline (baseline: 177.8 ± 36.68 mm3; three months: 182.25 ± 39.58 mm3, P=0.048). CONCLUSION: COVID-19 infection may affect the cornea and anterior segment.

Spatial and temporal variation of dissolved heavy metals in the Lijiang River, China: implication of rainstorm on drinking water quality.

Lijiang River is an essential drinking water source and natural scenery in the Guilin City. For the first time, implications of rainstorm were taken into consideration by investigating spatial and temporal variation of dissolved heavy metals (HMs) in the Lijiang River water. A total of 68 water samples were collected during low flow (normal) season and high flow (rainstorm) season from 34 sampling sites. Dissolved HMs including Cr, Mn, Co, Cu, Zn, As, Cd, Sb, and Pb were found to meet the respective drinking water standards, while comparatively higher concentration was observed after the rainstorm season, except for Cr. Multivariate statistical analysis showed that Co, Cu, Cr, Zn, Sb, and Pb in normal season were mainly controlled by anthropogenic sources. Furthermore, higher concentrations of Mn, Cu, Cd, Pb, Co, and Zn during the high flow season were attributed to rainstorm. The water quality index (WQI) showed good grades and comparatively lower in rainstorm season. The results of health risk assessment revealed that HMs in Lijiang River posed limited health risk; however, As posed potential health risk specially in rainstorm season. It is suggested to adopt preventive measures for mining activities and industrial waste-water discharge at the river's upstream and downstream.

Control of a two-DOF parallel robot with unknown parameters using a novel robust adaptive approach.

Model-based methods lose their performance in confronting with model uncertainties and disturbances. Accordingly, some degrees of adaptation to the involved conditions are required. In this paper, a novel robust adaptive scheme is proposed which guarantees the simultaneous identification and control of a system in the presence of external disturbances. Thereafter, the suggested algorithm is implemented on a 2-DOf spherical parallel robot as a stabilizer device. By identifying unknown parameters of Jacobian matrix, the relative identification error is obtained as 0.0207. Applying external excitations to the base, the ratio of end-effector to base orientation is acquired as 0.091, demonstrating proper stabilization in comparison with other two well-known methods. The proposed structure also reveals a reliable performance in tracking desired paths for the end-effector Euler angles.

Phacoemulsification, visco-goniosynechialysis, and goniotomy in patients with primary angle-closure glaucoma: A comparative study.

OBJECTIVE: The aim of this study was to evaluate the effects of goniotomy on patients with primary angle-closure glaucoma who underwent "phacoemulsification and visco-goniosynechialysis." MATERIALS AND METHODS: This prospective randomized clinical trial was carried out on 63 eyes of 61 patients (48-85 years) with primary angle-closure glaucoma who were enrolled. The subjects were randomly assigned into two groups. In the first group (32 eyes) and the second group (31 eyes), the patients underwent "phacoemulsification + visco-goniosynechialysis + goniotomy" and "phacoemulsification + visco-goniosynechialysis," respectively. Intraocular pressure and antiglaucoma medication were evaluated (1 week, as well as 1, 3, and 6 months after the surgery). Anterior segment optical coherence tomography parameters (Casia, Tomey, USA) and goniotomy were evaluated preoperatively and 6 months after the surgery. RESULTS: The mean intraocular pressure lowering the effects in the "phacoemulsification + visco-goniosynechialysis + goniotomy" group was higher than that in the "phacoemulsification + visco-goniosynechialysis" group (6.93 and 4.6, respectively). Furthermore, the difference in intraocular pressure between the two groups was significant at 3 months (P = 0.014) and 6 months (P = 0.021) after the surgery. There was no difference in anterior segment optical coherence tomography findings before the intervention; however, after the intervention, the anterior segment optical coherence tomography indices were significantly different between the two groups. Moreover, the difference in "phacoemulsification + visco-goniosynechialysis + goniotomy" indices was more than the changes in the "phacoemulsification + visco-goniosynechialysis" group. CONCLUSION: The results of this study showed that phacoemulsification + visco-goniosynechialysis + goniotomy is a more effective surgery than phacoemulsification + visco-goniosynechialysis alone in undercounted primary angle-closure glaucoma.

Activities and polymorphisms of MMP-2 and MMP-9, smoking, diabetes and risk of prostate cancer.

Matrix metalloproteinases (MMPs) are a group of zinc dependent enzymes that are involved in tumor cell invasion and metastasis. The role of MMP-2 and -9 genetic polymorphism in different malignancies has been the subject of numerous studies. The present research has attempted to discover any positive correlation between MMP-2 and MMP-9 SNPs and prostate cancer (PCa) in patients with a history of either diabetes or smoking habits. 112 PCa-patients and 150 unrelated healthy-controls that matched for age and sex were selected for present case-control study. MMP-2 -1575G/A and MMP-9 -1562 C/T polymorphisms detected by PCR-RFLP, serum tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2), testosterone, prostate-specific antigen (PSA), free-prostate-specific-antigen (fPSA), and fPSA/PSA levels were detected by ELISA and enzyme assay, respectively. MMP-2 and MMP-9 activities were measured by gelatin-zymography. Covariates were considered as age, status of cigarette smoking, and a possible history of diabetes mellitus (DM). The frequency of -1575 MMP-2 A/A + A/G and -1562 MMP-9 C/T + T/T genotypes were higher in PCa-patients with DM (74.3%,p = 0.003) and with smoking habits (72.5%,p = 0.005). These genotypes were associated with the increased risk of prostate cancer in smokers (3.52-folds) and in individuals with history of DM (4.34-folds). A significant positive association was found between level of TIMPs (TIMP -1 and TIMP-2) and BMI in PCa-patients and also between testosterone levels and MMP-9 activity in healthy control subjects. For the first time, this study demonstrated that activities of MMP-2 -1575G/A and MMP-9 -1562C/T variants in association with smoking and diabetes are considered significant risk factors for PCa.

Occurrence, distribution, and health risk assessment of quinolone antibiotics in water, sediment, and fish species of Qingshitan reservoir, South China.

The residual antibiotics in the environment have lately caused widespread concerns. However, little information is available on the antibiotic bioaccumulation and its health risk in drinking water resources of South China. Therefore, the occurrence, distribution, and health risk of four quinolone antibiotics including ofloxacin (OFX), norfloxacin (NOR), ciprofloxacin (CIP), and enrofloxacin (ENR) in the Qingshitan reservoir using high-performance liquid chromatography were investigated. Results revealed that the concentrations in water, sediment, and edible fish ranged from 3.49-660.13 ng/L, 1.03-722.18 µg/kg, and 6.73-968.66 µg/kg, respectively. The ecological risk assessment via the risk quotient (RQ) method showed that the values in sediment were all greater than 1, posing a high risk to the environment. The health risk index of water samples was at the maximum acceptable level, with OFX at the top while the rest were at the medium risk level. The main edible fish kinds of the reservoir had high dietary safety and the highest contaminations were found in carnivorous feeding habits and demersal habitat fishes with OFX as the highest magnitude. Source identification and correlation analysis using SPSS showed significant relationships between NOR with pH and turbidity (in water), as well as total phosphor (TP) and total organic carbon (TOC) in sediment. NOR was the highest in sediment which mostly sourced from livestock wastewater, croplands irrigation drain water, and stormwater. Correlations between CIP and ENR with TP were significant, while OFX was positively associated with total nitrogen (TN) which mainly originated from urban sewage as well as directly dosed drugs in fish farms. In conclusion, our results are of great significance for ensuring the safety of drinking water and aquatic products in this region.

Assimilation of exogenous cyanide cross talk in Oryza sativa L. to the key nodes in nitrogen metabolism.

Exogenous cyanide (CN-) effects on nitrogen (N) uptake, transport, and assimilation in rice seedlings were investigated at the biochemical and molecular levels. Seedlings were treated with either a 2-d or 4-d supply of potassium cyanide (KCN) in the nutrient solution containing nitrate (NO3-) or ammonium (NH4+). Although a KCN-induced increase was recorded in the activity of ß-cyanoalanine synthase (ß-CAS) in rice tissues of both NH4+-fed and NO3--fed seedlings, the former showed a significantly greater assimilation rate for CN- than the latter. The addition of KCN decreased NO3- uptake and assimilation, whereas a negligible impact was observed in NH4+ treatments. Enzymatic assays showed a marked activities enhancement of glutamine synthetase (GS), glutamate synthase (GOGAT), and glutamate dehydrogenase (GDH) in NH4+-fed seedlings after KCN exposure. Similarly, the rises occurring in nitrate reductase (NR) and GDH activity in NO3--fed seedlings were also detected after 2-d exposure to KCN, whereas a significant reduction of GS and GOGAT activities was determined. The results suggest that although exogenous KCN at moderate or high concentrations caused repressively effects on biomass growth of both NH4+-fed and NO3--fed rice seedlings, the nontoxic concentration of KCN supplied can serve as a supplemental N source in plant nutrition and N metabolism.

Pollution characteristics and toxicity of potentially toxic elements in road dust of a tourist city, Guilin, China: Ecological and health risk assessment☆.

Road dust samples from industrial, urban, and tourist areas of the international tourist city of Guilin, China, were collected to study the concentration, spatial distribution, pollution level, and health risk of potentially toxic elements (PTEs) using an array-based risk assessment model from the United States Environmental Protection Agency. The geoaccumulation index (Igeo), ecological risk index, and spatial interpolation were used to investigate the road dust pollution level. The results indicated that apart from Ni and Al, the concentration of all the heavy metals (Pb, Zn, Ni, Cu, Cr, Cd, Fe, Mn, and As) were markedly higher than the corresponding background values in the three functional areas. Based on the Igeo, the study area had an uncontaminated to moderate pollution level, and the industrial area was slightly more polluted and posed a greater ecological risk than the urban and tourist areas. Comparatively, Pb, Zn, and Cu exhibited higher pollution levels in the three functional sites. Hotspots of PTEs were more concentrated in urban and industrial areas than in tourist areas. Furthermore, the health risk model revealed significant non-carcinogenic risks to children from As in urban, industrial, and tourist areas as the hazard quotients (1.64, 2.04, and 1.42, respectively) exceeded the threshold standard of 1.00. The carcinogenic risk via ingestion (RIing) illustrated significant risks to children from Cr, As, and Ni because the RIing values were considerably higher than the threshold standard (1.00E-6 to 1.00E-4) in the three functional areas. However, no cancer risk was observed from the dermal and inhalation pathways.

Application of non-cooperative dynamic game theory for groundwater conflict resolution.

The opposing objectives of the groundwater stakeholders, ranging from maximum withdrawal for economic gain to minimum withdrawal for aquifer and environmental protection, lead stakeholders to behave non-cooperatively. In this study, dynamic non-cooperative games are applied to model these conflicts. These games incorporate stakeholders' non-cooperative decision-making processes and groundwater exploitation details over time. The two key players considered in this study are the government, which aims to minimize the groundwater drawdown, and local farmers, who pursue maximum economic gain. In order to calculate the players' payoffs over the modeling period, a simulation-optimization model is developed. For evaluation, the proposed methodology is implemented in the Bad-Khaledabad study area in Iran. Therefore, two dynamic non-cooperative games are developed, considering weak governmental power and players' interaction. It is concluded that creating a transactional relationship, involving the cropping patterns changes and the irrigation efficiency enhancement, will increase farmers' profits by 28% and decrease withdrawal from the aquifer by 21%.