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Combining genetic data with ecological niche models is an effective approach for exploring climatic and nonclimatic environmental variables affecting spatial patterns of intraspecific genetic variation. Here, we adopted this combined approach to evaluate genetic structure and ecological niche of the Indian gray mongoose (Urva edwardsii) in Iran, as the most western part of the species range. Using mtDNA, we confirmed the presence of two highly differentiated clades. Then, we incorporated ensemble of small models (ESMs) using climatic and nonclimatic variables with genetic data to assess whether genetic differentiation among clades was coupled with their ecological niche. Climate niche divergence was also examined based on a principal component analysis on climatic factors only. The relative habitat suitability values predicted by the ESMs for both clades revealed their niche separation. Between‐clade climate only niche comparison revealed that climate space occupied by clades is similar to some extent, but the niches that they utilize differ between the distribution ranges of clades. We found that in the absence of evidence for recent genetic exchanges, distribution models suggest the species occurs in different niches and that there are apparent areas of disconnection across the species range. The estimated divergence time between the two Iranian clades (4.9 Mya) coincides with the uplifting of the Zagros Mountains during the Early Pliocene. The Zagros mountain‐building event seems to have prevented the distribution of U. edwardsii populations between the western and eastern parts of the mountains as a result of vicariance events. Our findings indicated that the two U. edwardsii genetic clades in Iran can be considered as two conservation units and can be utilized to develop habitat‐specific and climate change‐integrated management strategies., Combining genetic data with ecological niche modeling is an effective approach for defining conservation units and exploring environmental variables that affect spatial patterns of genetic variation. We found two distinct genetic clades within H. edwardsii significantly correlated with different climate features. Niche‐based distribution models revealed that the two molecular clades occupy distinct environmental spaces, which are not similar, and equivalent.

Interspecific hybridization increasingly occurs in the course of anthropogenic actions, such as species translocations and introductions, and habitat modifications or occurs in sympatric species due to the shortage of conspecific mates. Compared with anthropogenically caused hybridization, natural hybridization is more difficult to prove, but both play an important role in conservation. In this study, we detected hybridization of two gazelle sister species, Gazella bennettii (adapted to dry areas) and Gazella subgutturosa (adapted to open plains), in five habitat areas, where G. bennettii naturally occur in central Iran. The hybrids have a nuclear genomic identity (based on two introns), habitat preference, and phenotype of G. bennettii, but the mitochondrial identity (based on cyt b) of G. subgutturosa. We suggest that natural hybridization of female G. subgutturosa and male G. bennettii happened twice in central Iran in prehistoric times, based on the haplotype pattern that we found. However, we found indications of recent hybridization between both species under special circumstances, for example, in breeding centers, due to translocations, or in areas of sympatry due to the shortage of conspecific mates. Therefore, these two species must be kept separately in the breeding centers, and introduction of one of them into the habitat of the other must be strictly avoided.

In the present study, we demonstrate comprehensive three-dimensional breakthrough pollutant advection-dispersion curve predictions throughout the 3D block of a highly heterogeneous fractured aquife...

INTRODUCTION There are no guidelines regarding management of failed pediatric renal transplants. MATERIALS & METHODS We performed a first of its kind multicenter study assessing prevalence of transplant nephrectomy, patient characteristics, and outcomes in pediatric renal transplant recipients with graft failure from January 1, 2006, to December 31, 2016. RESULTS Fourteen centers contributed data on 186 pediatric recipients with failed transplants. The 76 recipients that underwent transplant nephrectomy were not significantly different from the 110 without nephrectomy in donor or recipient demographics. Fifty-three percent of graft nephrectomies were within a year of transplant. Graft tenderness prompted transplant nephrectomy in 91% (P

Aim The Asiatic cheetah, Acinonyx jubatus venaticus, a critically endangered large felid, has disappeared from vast tracks of its historical range across south-western Asia. It is currently confined to the arid ecosystems of central Iran for which little is known about its distribution and habitat linkages. We proposed the first evaluation of Asiatic cheetah's distribution and developed models of landscape suitability and connectivity to inform future conservation planning. Location Central Iran. Methods We analysed presence data of a 14-year-long cheetah monitoring programme according to environmental and anthropogenic factors, and generated an ensemble model of habitat suitability based on seven species distribution models (SDMs). We then used the concept of circuit theory and landscape connectivity prioritization (LCP) on resultant core habitats and landscape suitability to evaluate potential linkages between core areas. Results Core habitats, that is, the areas hosting the largest continuous suitable habitats for Asiatic cheetahs, covered approximately 49,144 km2 (c. 6.3% of the study area). Availability of prey species, avoidance of human-dominated areas and their infrastructures, and rough landscapes covered with sparse vegetation were the most predictive factors of the core habitats for the last cheetah population in Asia. Although relatively vast, the area of potential core habitats available to cheetahs appeared to be fragmented with limited connectivity between the northern and southern parts of this distribution. Main conclusions Our approach highlights the importance of distribution models to recognize, at a coarse-scale level, a spatial population structure and habitat suitability characteristics for a large carnivore surviving at very low density. We have identified specific areas of suitable habitat where developing new landscape protection and adaptive conservation management; and improving the safety of important linkages between core habitats are likely to promote the conservation of the last surviving population of cheetah in Asia.

In the present work, the electrochemical oxidation of nitrite on carbon ceramic electrode (CCE) modified with multi-walled carbon nanotubes (MWCNTs) was investigated. The modified electrode exhibited catalytic activity toward the electrooxidation of nitrite. Experimental parameters such as solution pH, scan rate, concentration of nitrite and nanotubes amount were studied. It was shown nitrite can be determined by differential pulse voltammetry (DPV) and hydrodynamic amperometry (HA) using the modified electrode. Under the optimized conditions the calibration plots are linear in the concentration ranges of 15-220 and 50-3000 μM with limit of detections of 4.74 and 35.8 μM for DPV and HA, respectively. The modified electrode was successfully applied for analysis of nitrite in spinach sample. The results were favorbly compared to those obtained by UV-Visible spectrophotometric method. The results of the analysis suggest that the proposed method has promise for the routine determination of nitrite in the examined products.

A highly selective and simple chemiluminescence (CL) method for determination of penicillin G potassium (PGK) was developed. In the proposed method, CL was elicited from PGK upon its oxidation with H2O2. The light emission was enhanced in the presence of N-cetyl-N,N,N-trimethylammonium bromide (CTMAB). An experimental design, central composite design (CCD), was used to realize the optimized variables, including pH, surfactant (CTMAB) and H2O2 concentrations. Under optimum condition, the calibration graph was linear in the range 3.3 × 10−3–3.3 × 10−1 mmol/L, with a detection limit of 8.8 × 10−4 mmol/L for PGK. The precision was calculated by analysing samples containing 1.6 × 10−1 mmol/L PGK (n = 5) and the relative standard deviation (RSD) was 1.40%. The utility of this method was demonstrated by determining PGK in pharmaceutical formulations for injection. The proposed method was validated by a reference method. Copyright © 2011 John Wiley & Sons, Ltd.

INTRODUCTION: The development of Epstein-Barr virus (EBV) infection and post-transplant lymphoproliferative disorder (PTLD) is normally associated with a high EBV viral load in peripheral blood. Observations have previously identified existence of a chronic EBV high load (CHL) carrier state which demonstrated variable outcomes based upon the organ which was transplanted. Data defining the incidence and outcome of CHL in pediatric kidney transplantation (KTx) are not well described. METHODS: The charts of children undergoing isolated KTx at Children’s Hospital of Pittsburgh between January 2000 and December 2014 were retrospectively reviewed. EBV loads in the peripheral blood were routinely measured as part of surveillance protocols at our center. CHL was defined as the presence of high load for >50% of samples for ≥6 months. PTLD was defined histologically using WHO definitions. RESULTS: Of 188 isolated KTx recipients, we identified a total of 16 (8%) children who developed CHL carrier state. No patient developed EBV-driven late onset PTLD. Age at the time of KTx was significantly lower in CHL group (median 3.9 years, interquartile range: IQR 2.9-6.6, p=0.0004). Children in the CHL group were more likely to be EBV seronegative prior to KTx (94%, 15/16), compared to the undetectable viral load (UVL) and low viral load (LVL) groups (55% and 50%, respectively, p

An electroanalytical strategy for the simultaneous determination of ascorbic acid (AA) and dehydroascorbic acid (DHA), is described. A palladized Al electrode is used for hydrodynamic amperometry of AA. While the decrease of anodic stripping voltammetry current of the K2UO2[Fe(CN)6]-Pd/Al electrode prepared in the presence of DHA was the principal of the DHA determination. The calibration graph for both methods was linear over the concentration range 1 – 50 mM. The detection limit was found to be 0.5 mM. Some fresh fruit juices and vegetables of trace level of AA and DHA were analyzed as the typical example of application.