Polycyclic aromatic hydrocarbons exposures and telomere length: A cross-sectional study on preschool children.

Exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with shorter telomere length (TL), a marker of ageing at cellular level. However, the available evidence on this association among children is still scarce. We therefore aimed to assess, the relationship between urinary 1-hydroxipayrene (1-OHP), a marker of exposure to PAHs, and relative leukocyte TL (LTL) in children at preschool age. Our study was based on 200 children enrolled from 27 randomly-selected kindergartens in the city of Sabzevar, Iran (2017). 1-OHP levels in the participants' urine samples were measured using solid phase extraction (SPE) method and high-performance liquid chromatography (HPLC). Moreover, real-time PCR was used to measure the LTL in the participants' blood samples. Linear mixed effects models, controlled for relevant covariates, were applied to investigate the association of 1-OHP concentration and LTL. The median (interquartile range (IQR)) of relative LTL and urinary 1-OHP were 0.83 (0.7) and 257 (375.5) ng/L, respectively. In the fully adjusted model, an IQR increase in urinary 1-OHP was related to -0.05 (95% confidence interval (CI): 0.09, -0.01, P-value = 0.02) decrease in relative LTL. This association was similar among boys and girls; however, we observed indications for a stronger association for those children whose parents had university education. Our study suggested an inverse relationship between urinary 1-OHP and LTL in children at preschool age. However, further longitudinal research with repeated measures of PAHs and LTL are needed to confirm these findings.

Accounting for job satisfaction: Examining the interplay of person and situation.

In the present study, we investigate the interplay of personality traits (i.e., person) in frontline care staff in nursing homes and the way they relate to the residents (i.e., situation) to account for their job satisfaction. Participants completed a survey including Mini-IPIP tapping the five-factor model of personality, Individualized Care Inventory tapping four aspects of person-centered care and job satisfaction. The results revealed that staff scoring high on neuroticism experienced less job satisfaction. This relationship was partly accounted for by resident autonomy, suggesting that part of the adverse influence of neuroticism on job satisfaction may be mitigated by organizations providing a supportive care environment. In contrast, staff scoring high on agreeableness experienced higher job satisfaction. This relationship was accounted for by another aspect of person-centered care, that is, knowing the person. This suggests that agreeableness in a sense facilitated adjustment of acts of care toward the unique needs and preferences of residents and this partly explained why the more agreeable the staff was the more they felt satisfied at work. In sum, effects of personality traits on job satisfaction in care staff are partially mediated by the perception of working conditions and care policy and to the extent that a certain personality trait affects whether the staff have a positive or negative perception of the way they relate to the residents, they will experience, respectively, higher or a lower job satisfaction. This finding has implications for how to combine a focus on delivering person-centered care with improving personal job satisfaction.

The Effect of Dexmedetomidine on Postoperative Opioid Consumption and Pain After Major Spine Surgery.

BACKGROUND: Adult deformity correction spine surgery can be associated with significant perioperative pain because of inflammatory, muscular, neuropathic, and postsurgical pain. α-2 Agonists have intrinsic antinociceptive and antihyperalgesic properties that can potentially reduce both postoperative opioid consumption and pain. We hypothesized that intraoperative dexmedetomidine would reduce postoperative opioid consumption and improve pain scores in deformity correction spine surgery. METHODS: Patients undergoing >3 levels of thoracic and/or lumbar spine surgery were enrolled in this prospective randomized double-blind study to receive either dexmedetomidine (1 µg/kg load followed by a continuous infusion of 0.5 µg/kg/h) or saline. Both groups received a single dose of 0.2 mg/kg (ideal body weight) of methadone at the start of surgery. Intraoperative fentanyl was administered based on the clinical and hemodynamic signs suggestive of increased nociception. Postoperative analgesia was provided with a hydromorphone patient-controlled analgesia pump. Opioid consumption and pain scores were recorded at 24, 48, and 72 hours after surgery. RESULTS: One hundred forty-two participants were enrolled with 131 completing the study. There was no significant difference in demographics (age, sex, weight, and ASA physical status), percentage of participants with preoperative opioid use, and daily median opioid consumption between the groups. The study was terminated early after interim analysis. Intraoperative opioid use was reduced in the dexmedetomidine arm (placebo versus dexmedetomidine, median [25%-75% interquartile range]: 7 [3-15] vs 3.5 [0-11] mg morphine equivalents, P = 0.04) but not at 24 hours: 49 (30-78) vs 61 (34-77) mg morphine equivalents, P = 0.65, or 48 hours: 41 (28-68) vs 40 (23-64) mg morphine equivalents, P = 0.60, or 72 hours: 29 (15-59) vs 30 (14-46) mg morphine equivalents, P = 0.58. The Wilcoxon-Mann-Whitney odds are 1.11 with 97.06% confidence interval (0.71-1.76) for opioid consumption. No difference in pain score, as measured by the 11-point visual analog scale, was seen at 24 hours (placebo versus dexmedetomidine, median [25%-75% interquartile range]: 7 [5-7] vs 6 [4-7], P = 0.12) and 48 hours (5 [3-7] vs 5 [3-6], P = 0.65). There was an increased incidence of bradycardia (placebo: 37% vs dexmedetomidine: 59% P = 0.02) and phenylephrine use in the dexmedetomidine group (placebo: 59% versus dexmedetomidine: 78%, P = 0.03). CONCLUSIONS: Intraoperative dexmedetomidine does not reduce postoperative opioid consumption or improve pain scores after multilevel deformity correction spine surgery.

Advancing the Big Five of user-oriented care and accounting for its variations.

PURPOSE: Care process quality (i.e. how care is enacted by a care worker toward a client at the interpersonal level) is a strong predictor of satisfaction in a wide range of health care services. The purpose of this paper is to describe the basic elements of care process quality as user-oriented care. Specifically, the questions of how and why quality in user-oriented care varies were investigated in the context of elderly care. DESIGN/METHODOLOGY/APPROACH: Two municipalities were selected for in-depth field studies. First, in each municipality, the authors interviewed and observed care workers' interactions with the older persons in both home care and nursing homes during two weeks (Study 1). Second, in an attempt to gain a deeper understanding of why process quality in terms of user-oriented care varies, the authors conducted interviews with care workers and care unit managers (Study 2). FINDINGS: A new taxonomy for categorizing process quality variation, the Big Five of user-oriented care (task-focus, person-focus, affect, cooperation, and time-use), is proposed. In addition, the perceived reasons for process quality variation are reported in our own developed Quality Agents Model, suggesting that variations in care process evaluations may be explained from different perspectives at multiple levels (i.e., older person, care worker-, unit-, department-, and municipality level). ORIGINALITY/VALUE: The proposed taxonomy and model are useful for describing user-oriented care quality and the reasons for its variations. These findings are of relevance for future quality developments of elderly care services, but also may be adapted to applications in any other enterprise employing a user-oriented approach.

Spatial health risk assessments of nickel in the groundwater sources of a mining-impacted area.

Mining activities have increased the potential risks of metal pollution to the groundwater resources in arid areas across the globe. Therefore, this study aimed to examine the health risk associated with nickel (Ni) in the groundwater sources of a mining-impacted area, South Khorasan, Eastern Iran. A total of 110 stations were included in the study, comprising 62 wells, 40 qanats, and 8 springs in summer, 2020. Initially, the collected samples were tested for temperature, pH, and electrical conductivity (EC). Subsequently, the samples were filtered and treated with nitric acid (HNO3) to measure the concentration of Ni using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Hazard quotient (HQ) and non-carcinogenic risk assessments were employed to evaluate the potential risks of Ni to the inhabitants. The findings revealed that the concentration of Ni ranged from 0.02 to 132.39 µg l-1, and only two stations exhibited Ni concentrations above the WHO standards (20 µg l-1). The results demonstrated that 98.21% of the sampled locations had HQ values below one, indicating negligible risk, while 1.78% of the stations exhibited HQ values of one or higher, representing a high non-carcinogenic risk for water consumers. Overall, the concentration of nickel in the groundwater of South Khorasan exceeded the World Health Organization (WHO) limit solely in the Halvan station, posing a non-carcinogenic risk for the residents in that area, and therefore, additional efforts should be made to provide healthier groundwater to consumers in this region.

Total Intravenous Anesthesia with Propofol Reduces Discharge Times Compared with Inhaled General Anesthesia in Shoulder Arthroscopy: A Randomized Controlled Trial.

BACKGROUND: Shoulder arthroscopy is commonly performed at ambulatory surgical centers (ASCs) with use of an interscalene block and inhaled general anesthesia (IGA). However, an alternative option known as total intravenous anesthesia with propofol (TIVA-P) has shown promising results in reducing recovery time for other surgeries. The objective of this study was to assess whether there is a clinically meaningful difference in post-anesthesia care unit phase-I (PACU-I) time following shoulder arthroscopy between patients receiving an interscalene block with IGA and those receiving an interscalene block with TIVA-P. METHODS: Patients who underwent shoulder arthroscopy performed by a single surgeon at the ASC of our institution between 2020 and 2023 were enrolled. Enrollment was conducted in blocks, with up to 3 planned interim analyses. After 2 blocks, enrollment was halted because the study arms demonstrated a significant difference in the primary outcome measure, PACU-I time. A total of 96 patients were randomized into the TIVA-P and IGA groups; after patient withdrawals, the groups comprised 42 and 40 patients, respectively. Patients underwent shoulder arthroscopy with use of the anesthesia method corresponding to their assigned group. Pain, satisfaction, antiemetic use, perioperative interventions, surgical time, PACU-II time, postoperative care time, and total time until discharge were recorded and were analyzed with use of chi-square and Mann-Whitney U tests with a significance cutoff of 0.0167 to account for the interim analyses. RESULTS: Across groups, 81.7% of patients were non-Hispanic White and 58.5% were male. Significant differences were observed between the TIVA-P and IGA groups with respect to median PACU-I time (0.0 minutes [interquartile range (IQR), 0.0 to 6.0 minutes] versus 25.5 minutes [IQR, 20.5 to 32.5 minutes]; p < 0.001) and median total time until discharge (135.5 minutes [IQR, 118.5 to 156.8 minutes] versus 148.5 minutes [IQR, 133.8 to 168.8 minutes]; p = 0.0104). The TIVA-P group had a 9.1% quicker discharge time, primarily as a result of bypassing PACU-I (66.7% of patients) and spending 25.5 fewer minutes there overall. The TIVA-P group also had a lower rate of antiemetic use than the IGA group (59.5% versus 92.5% of patients; p = 0.0013). No significant differences were detected between the TIVA-P and IGA groups in terms of median pain improvement (1.0 [IQR, 0.0 to 2.0] versus 1.0 [IQR, 0.0 to 2.0]; p = 0.6734), perioperative interventions (78.6% versus 77.5% of patients, p = 1.0000), or median patient satisfaction (4.0 [IQR, 4.0 to 4.0] versus 4.0 [IQR, 3.8 to 4.0]; p = 0.4148). CONCLUSIONS: TIVA-P showed potential to improve both PACU-I time and the total time until discharge while reducing antiemetic use without impacting pain or satisfaction. TIVA-P thus warrants consideration by orthopaedic surgeons for use in shoulder arthroscopy performed at ASCs. LEVEL OF EVIDENCE: Therapeutic Level I . See Instructions for Authors for a complete description of levels of evidence.

Optimization by Box-Behnken design for environmental contaminants removal using magnetic nanocomposite.

In this study, a CoO-Fe2O3/SiO2/TiO2 (CIST) nanocomposite was synthesized and utilized as an adsorbent to remove methylene blue (MB), malachite green (MG), and copper (Cu) from aqueous environments. The synthesized nanocomposite was characterized using field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). Input parameters included pH (3-10), contact time (10-30 min), adsorbent amount (0.01-0.03 g), and pollutant concentration (20-60 mg L-1). The effects of these parameters on the removal process efficiency were modeled and optimized using the response surface methodology (RSM) based on the Box-Behnken design (BBD). The RSM-BBD method demonstrated the capability to develop a second-degree polynomial model with high validity (R2 ˃ 0.99) for the removal process. The optimization results using the RSM-BBD method revealed a removal efficiency of 98.01%, 93.06%, and 88.26% for MB, MG, and Cu, respectively, under optimal conditions. These conditions were a pH of 6, contact time of 10 min, adsorbent amount of 0.025 g, and concentration of 20 mg L-1. The synthesized adsorbent was recovered through five consecutive adsorption-desorption cycles using hydrochloric acid. The results showed an approximately 12% reduction from the first to the seventh cycle. Also, MB, MG, and Cu removal from real water samples in optimal conditions was achieved in the range of 81.69-98.18%. This study demonstrates the potential use of CIST nanocomposite as an accessible and reusable option for removing MB, MG, and Cu pollutants from aquatic environments.

Mercury(II) and lead(II) ions removal using a novel thiol-rich hydrogel adsorbent; PHPAm/Fe3O4@SiO2-SH polymer nanocomposite.

The abundant release of toxic heavy metals into wastewater has been a serious threat to human health, aquatic environments, plants, and animals; thus, it is critical to purify wastewater of these pollutants through a proper treatment process. A novel hydrogel compound was synthesized using partially hydrolyzed polyacrylamide (PHPAm) and functionalized Fe3O4-coated magnetic nanoparticles (PHPAm/Fe3O4@SiO2-SH) that is efficient in removal of mercury and lead from wastewater. This new magnetic nanoadsorbent is characterized using scanning electron microscope, Fourier-transform infrared, thermogravimetric analysis, vibrating sample magnetometer, and energy-dispersive X-ray analysis. The central composite design under response surface methodology (CCD-RSM) was applied in designing the experiments to optimize the main parameters affecting the adsorption capacity: initial concentration (77.50 mg L-1), pH (6.11 and 6.48), adsorbent dosage (25 mg), and contact time (115 and 106 min) for both Hg2+ and Pb2+ adsorption, respectively. Quadratic models were used for variable predictions and analysis of variance was applied to evaluate the statistical parameters and investigate the interactions of the variables. The high determination coefficient (R2 0.99) for both metals indicates a good correlation between actual and predicted response values. Additionally, thermodynamic modeling showed an endothermic and exothermic for Hg2+ and Pb2+, respectively, and also the spontaneous nature of both metals' adsorption process within the temperature range of 288-318 K. Mercury and lead kinetic studies were in agreement with pseudo-second-order modeling, and the equilibrium results revealed that the Langmuir isotherm best fit the experimental data with maximum adsorption capacities of 256.41 and 227.27 (mg g-1) for Hg2+ and Pb2+, respectively. Overall, PHPAm/Fe3O4@SiO2-SH is thought to have highly promising potential for investigating heavy metals in wastewater treatment, and will make important contributions to similar studies that may be conducted in the future.

Endodontic Management of Three-rooted Mandibular First Premolar Using Cone-beam Computed Tomography: A Case Report.

The anatomy of the root canal system always affects endodontic treatment outcomes. Mandibular premolar teeth demonstrate extreme variations in root canal morphology. Mandibular first premolars typically exhibit basic single-root and single-canal anatomy. The occurrence of three roots in the mandibular first premolar has not been commonly reported in the literature. This article reported a case of a 26-year-old male with spontaneous pain of the mandibular first premolar representing the presence of an extra canal on the periapical radiograph. Cone-beam computed tomography (CBCT) was used to assess the root canal details which led to the finding of three canals. Further, a periapical bone defect was detected, and finally, the nonsurgical endodontic management of the mandibular first premolar with three canals and three different apical foramina was performed in one session.

Ecological assessment of Iran's terrestrial biomes for wildlife conservation.

Man-made activities pose the greatest threats to wildlife in Iran's terrestrial biomes, causing significant habitat damage and fragmentation in recent years. To fully understand these threats, the present study was conducted to identify and map the Iran's terrestrial biomes using the IDRISI TerrSet 18.31 Software, the Terrestrial Biomes Ecosystem Service Modeler on the InVEST toolkit (TBESMI), and comprehensive data sources including maps of roads, protected areas, terrestrial biomes, and country-wide land cover maps of 2017. The results showed that the largest terrestrial biome in Iran is deserts and xeric shrublands (DXS), while flooded grasslands and savannas (FGS) is the smallest biome. Roads, along with urban and agricultural developments are among the biggest threats and most destructive stressors in Iran's terrestrial biomes. The results also revealed that there was a growth in destruction of habitats located in the temperate broadleaf and mixed forest (TBMF), temperate coniferous forest (TCF), and FGS, alongside a decrease in the DXS biome. Furthermore, we detected an increase in habitat landscape quality in the DXS, FGS and montane grasslands and shrub lands (MGS), and a decrease in the temperate grasslands, savannas and shrublands (TGSS) and TBMF biomes. Finally, the cumulative risk of habitat degradation increased in the FGS, TCF, TGSS, and TBMF biomes, whereas it decreased in the DXS biome. The FGS biome with the highest consequence cumulative score, and the MGS biome with the highest cumulative risk exposure score were found to be at the highest risk from man-made activities. Stressors associated with agriculture and urbanization had the highest cumulative exposure scores in the MGS, while roads had the highest exposure scores in the TBMF and DXS biomes. Our study underscores the critical importance of conserving Iran's terrestrial biomes and wildlife, especially in high-risk biomes like FGS and MGS, given the substantial threats posed by human activities.

Negative health impact of tourists through pandemic: hospitality sector perspective.

Although the impact of tourism development on residents has received a lot of attention in the literature, the health impact of tourism has not been sufficiently addressed. Due to outbreaks of COVID-19, the importance of recognition of the negative health impact of tourism is relevant. Thus, the present study aims to identify the health impact of tourism through COVID-19 outbreaks considering residents' perspectives. In the current research, we gathered data from semi-structured interviews conducted from 10th August to 30 August 2020 to investigate community perception regarding the negative health impact of tourism through the COVID-19 era. We conducted 30 interviews with some Iranian residents. Data is analyzed by thematic analysis via MAXQDA software. Residents perceived negative health impacts through COVID-19 outbreaks as containing three subthemes including general negative impacts, direct negative impacts, and indirect negative impacts. The results also show that residents use two coping strategies to face these negative health impacts, namely negative coping strategies and positive coping strategies. Perceived negative health impacts, and residents' coping strategies are two major themes regarding Iranian residents' perception toward tourism negative health impacts through COVID-19 outbreaks.

Finite Element Analysis of Fracture Resistance of Mandibular Molars with Different Access Cavity Designs.

INTRODUCTION: This study aimed to assess the fracture resistance of mandibular first molars after preparation with 3 different access cavity designs and 2 rotary systems using finite element analysis. METHODS: Six 3-dimensionally printed mandibular first molars simulating natural teeth received traditional, conservative, and ultraconservative (truss) access cavity preparations. The root canals in each group were instrumented with either XP-Endo Shaper (FKG Dentaire, La Chaux-de-Fonds, Switzerland) or TruNatomy (Dentsply Sirona, Ballaigues, Switzerland) rotary files. The models were individually digitized, and micro-computed tomographic scans were transferred to Mimics software (Materialise NV, Leuven, Belgium) to create a geometric model of the tooth. The designed model was exported to 3-matic software (Materialise NV), and STL files were transferred to Geomagic Design X (3D Systems, Rock Hill, SC). Point cloud data were used for surfacing and transferred to ANSYS software (Ansys, Canonsburg, PA). A 200-N superficial force was applied vertically to the buccal cusps and central fossa, and the maximum and minimum equivalent von Mises stress values were calculated and reported. RESULTS: The traditional and ultraconservative access cavity designs yielded the highest and the lowest von Mises stress values, respectively. In the ultraconservative cavity design, the stress values in pericervical dentin were lower in canal preparation with TruNatomy compared with XP-Endo Shaper. In the traditional and conservative cavity designs, stress was lower in the first 2 mm from the cementoenamel junction in the XP-Endo Shaper group and in the next 3 mm in the TruNatomy group. CONCLUSIONS: Stress was lower in the ultraconservative and conservative cavity designs compared with the traditional design. Also, root canal preparation with TruNatomy yielded lower stress values in general compared with XP-Endo Shaper.

A genome-wide association study of morphometric traits in dromedaries.

BACKGROUND: Investigating genomic regions associated with morphometric traits in camels is valuable, because it allows a better understanding of adaptive and productive features to implement a sustainable management and a customised breeding program for dromedaries. OBJECTIVES: With a genome-wide association study (GWAS) including 96 Iranian dromedaries phenotyped for 12 morphometric traits and genotyped-by-sequencing (GBS) with 14,522 SNPs, we aimed at identifying associated candidate genes. METHODS: The association between SNPs and morphometric traits was investigated using a linear mixed model with principal component analysis (PCA) and kinship matrix. RESULTS: With this approach, we detected 59 SNPs located in 37 candidate genes potentially associated to morphometric traits in dromedaries. The top associated SNPs were related to pin width, whither to pin length, height at whither, muzzle girth, and tail length. Interestingly, the results highlight the association between whither height, muzzle circumference, tail length, whither to pin length. The identified candidate genes were associated with growth, body size, and immune system in other species. CONCLUSIONS: We identified three key hub genes in the gene network analysis including ACTB, SOCS1 and ARFGEF1. In the central position of gene network, ACTB was detected as the most important gene related to muscle function. With this initial GWAS using GBS on dromedary camels for morphometric traits, we show that this SNP panel can be effective for genetic evaluation of growth in dromedaries. However, we suggest a higher-density SNP array may greatly improve the reliability of the results.

Distribution patterns of metals contamination in sediments based on type regional development on the intertidal coastal zones of the Persian Gulf, Iran.

This study was performed to determine the variation of metals concentrations (Pb, Cd, Zn, and Cu) in surface sediments based on type region development from ten sites on the intertidal coastal zone of the Persian Gulf, Iran. The metals concentrations in surface sediments varied from 0.86 to 180.78 µg g(-1) for Pb, 0.61 to 6.48 µg g(-1) for Cd, 5.99 to 44.42 µg g(-1) for Zn, and 3.01 to 43.33 µg g(-1) for Cu. The quality of the sediments was evaluated based on sediment quality guidelines (effects range-low (ERL) and effects range-medium (ERM) indexes. Biological effects criteria suggest that metals concentrations in sediments were lower than ERM for all sites, but for some sites metals concentrations in sediments were higher than ERL. The present results support the concept that human activities in each region could be a major source of metals pollution input in the aquatic environment.

Oyster Saccostrea cucullata as a biomonitor for Hg contamination and the risk to humans on the coast of Qeshm Island, Persian Gulf, Iran.

A total of 174 individuals of rocky oysters (Saccostrea cucullata) and 35 surface sediment samples were collected from seven stations off the intertidal zones of Qeshm Island, Persian Gulf, in order to study the concentration of mercury in oysters' tissues, and to investigate whether mercury concentrations in the edible soft tissues are within the permissible limits for public health. The average mercury concentrations were found as 3.44, 50.66 and 2.29 µg kg(-1) dw in the sediments, soft tissues and shells of the oysters, respectively. Results indicated that the levels of mercury in sediment differed significantly between the stations. In addition, results confirmed that the soft tissues of oysters could be a good indicator of mercury in the aquatic system. In comparison with food safety standards, mercury levels in oysters were well within the permissible limits for human consumption.

Osseous reaction to implantation of two endodontic cements: Mineral trioxide aggregate (MTA) and calcium enriched mixture (CEM).

AIM: The aim of the present in vivo study was to determine bone tissue reaction to calcium enriched mixture (CEM) and mineral trioxide aggregate (MTA) using a rat femur model. STUDY DESIGN: Sixty-three rats were selected and randomly divided into three groups of 21 each [experimental groups (n=15), control (n=6)]. Implantation cavities were prepared in each femoral bone and randomly filled with the biomaterials only in the experimental groups. The animals in three groups were sacrificed 1, 4, and 8 weeks postoperatively. Histologic evaluations comprising inflammation severity and new bone formation were blindly made on H&E-stained decalcified 6-µm sections. RESULTS: At 1, 4, and 8 weeks after implantation number of inflammatory cells had decreased in the CEM, MTA and control groups, respectively, with no statistically significant differences. Conversely, new bone formation had increased in all the experimental and control groups, without statistically significant differences. CONCLUSION: The results suggest that biocompatibility of MTA, as gold standard, and CEM cement as a new endodontic biomaterial are comparable.

Hydrochemical evaluation of groundwater quality and human health risk assessment of trace elements in the largest mining district of South Khorasan, Eastern Iran.

The groundwater resources of mining areas have been in a challenging condition in terms of metal pollution and human health. Therefore, this study investigated the concentration of cobalt (Co), molybdenum (Mo), selenium (Se), tin (Sn), and antimony (Sb) in groundwater samples (wells, qanats, and springs) in a heavily contaminated mining district, South Khorasan, Eastern Iran. Human health risk of the studied metals to target groups was assessed, and water quality of the studied groundwater was investigated in the study area. A total of 367 sampling sites (279 wells, 74 qanats, and 14 springs) in South Khorasan Province were selected to collect the groundwater samples from June to July 2020. Sampling was performed thrice for each sampling point, and hydrochemical parameters were evaluated using a portable multiparameter. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the metal concentrations. Results showed an order of Se > Mo > Sn > Co > Sb, and hazard index (HI) demonstrated a warning condition for south of South Khorasan (drinking application), southwest of South Khorasan (Irrigation application), and east and center of South Khorasan (drinking-irrigation application). Hydrochemical parameters showed a classification of "Na + K type" and "Mixed Ca-Mg-Cl type" with an overall group of "Na-Cl-HCO3" for sampled waters. Ficklin-Caboi diagram depicted a classification of "near-neutral low metal," and Schoeller diagram classified studied groundwater as "good" for drinking and irrigation consumptions and "Na-Cl" type based on ion balance diagram. Based on the correlation analysis, positive relationships were recorded among EC, TDS, Cl-, Na+, sulfate, Ca2+, salt, total hardness, Mg2+, ammonia, and K+ measured in the water samples. In essence, arid regions of the world greatly rely upon groundwater resources for drinking and irrigation consumptions, and mining districts with a heavy load of active mines can be a serious threat to the groundwater quality and human health.

Health risk assessment of total chromium in the qanat as historical drinking water supplying system.

This study investigated the health risk assessment of total chromium (CrT) in qanats of South Khorasan, Eastern Iran. For this, concentration of CrT in a total of 83 qanats were measured in summer 2020. Samples were initially tested in the field for temperature, pH, dissolved oxygen (DO), electrical conductivity (EC), and total dissolved solids (TDS). In the lab, collected samples were filtered and fixed with nitric acid (HNO3) for the detection of CrT using inductively coupled plasma mass spectrometry (ICP-MS). Hazard quotient (HQ) and carcinogenic risk assessments were considered to evaluate the risks of CrT to inhabitants. Results showed that concentration of CrT ranged from 1.79 to 1017.05 µg L-1, and a total of 25 stations illuminated CrT concentrations above the WHO standards (50 µg L-1). HQ demonstrated HQ < 1 for 90.37% of studied samples with negligible hazard, whereas 9.63% of stations illuminated HQ ≥ 1 meaning the presence of non-carcinogenic risk for water consumers. Carcinogenic risk (CR) exhibited CR > 1.00E-04 in 81.93% of qanats while 18.07% of stations had 1.00E-06 < CR < 1.00E-04 meaning no acceptable and acceptable CR for the studied qanats, respectively. Zoning map displayed that qanats in the south of South Khorasan possessed the highest HQ, but north regions showed the lowest ones. Together, CrT in qanats of South Khorasan is above the WHO limit, which results in a high risk of carcinogenicity for residents, and in turn, more efforts should be made to provide hygienic groundwater for consumers.

Endodontic Management of a Two-Rooted Maxillary Central Incisor Using Cone-Beam Computed Tomography: A Case Report.

Practitioners need to know the normal and complex anatomy of the root canal system of individual teeth. Maxillary central incisors almost in all cases have one root and one root canal system. This case report describes a non-surgical endodontic treatment of a double-rooted maxillary central incisor using cone-beam computed tomography (CBCT). A fourteen-year-old male with spontaneous pain of the maxillary left incisor showed the presence of an extra root on the periapical radiograph. CBCT was used to assess the root canal details that lead to finding a narrow root in the mesial of the main root. Also, a periapical bone defect was detected. Nonsurgical treatment of tooth performed. At the 3-month follow-up, the tooth was functional and the lesion was healed. Therefore, practitioners should consider the presence of extra roots and canals during root canal treatment. CBCT imaging helps in detecting the exact location of the extra root.

Determination of toxic metal burden and related risk factors in pregnant women: a biological monitoring in Sabzevar, Iran.

Nowadays, the adverse effect of toxic metals on humans is well known, especially in the fetal period such as preventing cognitive development and congenital abnormalities of the central nervous system. Hence, this study aims to evaluate the toxic metal burden in mothers and newborns in Sabzevar. Obtained data can be useful for authorities in public health issues. To determine heavy metals in placental blood and umbilical cord blood, one hundred eighty blood samples were taken from ninety mothers referred to Shahidan Mobini Hospital for delivery. The amount of metals in samples was analyzed using inductively coupled plasma optical emission spectrometry (ICP OES). The results of this study revealed that 21.52%, 26.19%, and 60.71% of maternal blood samples (placental blood) and 16.47%, 56.47%, and 20% of umbilical cord blood samples were higher than the US center for disease control (CDC) recommended levels for Pb, Cd, and As respectively. According to the multiple linear regression analysis, the Pb (p = 0.054), As (p < 0.001), and Se (p < 0.001) levels had an association with the mother's living area. Also, there was a significant association between Se (0.021) and the age of the mother. However, the Se values in its optimum concentrations in the blood (60-140 µg/L) can decrease the adverse effects of toxic metals, 72.5% of the pregnant women had Se values below the 60 µg/L and only 6% of pregnant women had Se levels higher than 140 µg/L. We concluded that the mothers inhabiting the rural areas need more Se sources in their diets.