Zircon U-Pb, geochemical and isotopic constraints on the age and origin of A- and I-type granites and gabbro-diorites from NW Iran

Highlights • There are Late Cretaceous granitoids and Paleocene A-type granites in NW Iran. • Different mechanisms are suggested for genesis of granitoids and A-type granites. • Subduction initiation and extension generated granitoids during the Late Cretaceous. Abstract The continental crust of NW Iran is intruded by Late Cretaceous I-type granites and gabbro-diorites as well as Paleocene A-type granites. SIMS and LA-ICPMS U-Pb analyses of zircons yield ages of 100–92 Ma (Late Cretaceous) for I-type granites and gabbro-diorites and 61–63 Ma (Paleocene) for A-type granites. Late Cretaceous gabbro-diorites (including mafic microgranular enclaves; MMEs) from NW Iran show variably evolved signatures. They show depletion in Nb and Ta on N-MORB-normalized trace-element spider-diagrams and have high Th/Yb ratios, suggesting their precursor magmas were generated in a subduction-related environment. Gabbro-diorites have variable zircon εHf(t) values of +1.2 to +8, δ18O of 6.4 to 7.4‰ and bulk rock εNd(t) of −1.4 to ~ +4.9. The geochemical and isotopic data attest to melting of subcontinental lithospheric mantle (SCLM) to generate near-primitive gabbros with radiogenic Nd isotopes (εNd(t) = ~ +4.9) and high Nb/Ta and Zr/Hf ratios, similar to mantle melts (Nb/Ta ~ 17 and Zr/Hf ~ 38). These mafic melts underwent further fractionation and mixing with crustal melts to generate Late Cretaceous evolved gabbro-diorites. Geochemical data for I-type granites indicate both Nb-Ta negative and positive anomalies along with enrichment in light REEs. These rocks are peraluminous and have variable bulk-rock εNd(t) (−1.4 to +1.3), zircon εHf(t) (+2.8 to +10.4) and δ18O (4.7–7.3‰) values, but radiogenic bulk rock Pb isotopes. The geochemical and isotopic signatures of these granites suggest interaction of mantle-derived mafic magmas (similar to near-primitive Oshnavieh gabbros) with middle-upper crust through assimilation-fractional crystallization (AFC) to produce Late Cretaceous I-type granites. Paleocene A-type granites have distinctive geochemical features compared to I-type granitoids, including enrichment in Nb-Ta, high bulk rock εNd(t) (+3.3 to +3.9) and zircon εHf(t) (+5.1 − +9.9) values. Alkaline granites are ferroan; they have low MgO, CaO, Sr, Ba and Eu concentrations and high total Fe2O3, K2O, Na2O, Al2O3, Ga, Zr, Nb-Ta, Th and rare earth element (REE) abundances and Ga/Al ratios. These rocks might be related to fractionation of a melt derived from a sub-continental lithospheric mantle, but which interacted with asthenosphere-derived melts. We suggest that subduction initiation and the resultant slab roll-back caused extreme extension in the overlying Iranian plate, induced convection in the mantle wedge and led to the decompression melting of SCLM. Rising mantle-derived magmas assimilated middle-upper crustal rocks. Fractionating mantle-derived magmas and contamination with crustal components produced evolved gabbro-diorites and I-type granites. In contrast, asthenospheric upwelling during the Paleocene provided heat for melting and interaction with SCLM to generate the precursor melts to the A-type granites

Existence of positive solutions for p(x)-Laplacian problems

We consider the system of differential equations $$displaylines{ -Delta_{p(x)} u=lambda [g(x)a(u) + f(v)] quadhbox{in }Omegacr -Delta_{q(x)} v=lambda [g(x)b(v) + h(u)] quadhbox{in }Omegacr u=v= 0 quadhox{on } partial Omega }$$ where $p(x) in C^1(mathbb{R}^N)$ is a radial symmetric function such that $sup| abla p(x)| < infty$, $1 < inf p(x) leq sup p(x) < infty$, and where $-Delta_{p(x)} u = -{ m div}| abla u|^{p(x)-2} abla u$ which is called the $p(x)$-Laplacian. We discuss the existence of positive solution via sub-super-solutions without assuming sign conditions on $f(0),h(0)$

An investigation into the sensitivity of shear wave ultrasound elastography to measure the anterior bladder wall pressure in patients with neurogenic bladder

Introduction and Objective: Urodynamic testing (urodynamics) is widely used for evaluating bladder function as a result of high detrusor compliance. This aggressive and uncomfortable test is especially difficult for children. This study aimed to determine the sensitivity of shear wave ultrasound elastography (SWE) as a new method for evaluating the biomechanical characteristics of bladder to measure the anterior bladder wall pressure in children with neurogenic bladder (NB). Materials and Methods: The present prospective clinical study was carried out on 30 children with allegedly NB and 20 healthy children as control group. These children referred to Ahwaz Golestan Hospital in 2018. After clinical evaluations, urodynamics was performed for children with NB and detrusor compliance was measured in cm/H2O. The ultrasonography of the SWE was performed on the anterior wall of the bladder (Estimated bladder capacity (EBC) 50%) for the two groups. The relationship between shear wave speed (SWS) and detrusor compliance was estimated using Pearson's correlation coefficient. Independent t-test was used to compare SWS between two groups. Results: In patients with NB, there was a significant relationship between the mean SWS of the anterior bladder wall and detrusor compliance (R = 0.89, P = 0.0001). The comparison between normal and NB groups showed that the mean SWS of the anterior bladder wall in the patients was significantly higher than the healthy group (1.88 ± 0.88 m/s vs. 0.94 ± 0.15; P = 0.0001). There was also no significant relationship between SWS, gender, age, weight, and body mass index of patients (P > 0.05). Conclusion: The results showed that SWE can be used as a useful alternative for urorodynamic testing in the evaluation of NB (bladder dysfunction) in children

Effect of thermal modification on the practical properties of horn beam bark flour-polypropylene composites

Current research was conducted to investigate the effect of thermal modification on practical properties of horn beam bark flour-polypropylene composites. Wood plastic composites were divided in two levels of control and thermal modification, both levels included of 4 groups in bark fillers; 10, 20, 30 and 40%. Test samples prepared with maleic anhydride-grafted polypropylene as coupling agent by injection molding method. According to the results, bark flour increased water absorption, tensile and bending modulus. High proportion of bark fillers declined mechanical strength. Thermal modification significantly improved physical and mechanical properties of composite. Using lignocellulosic material flour bark hornbeam, tensile modulus and flexural modulus of composite material background had the highest improvement. In comparison between mechanical properties, impact resistance by adding flour bark had the greatest decrease. Thermal modification by increasing the crystallity, hemicellulose degradation, loss of polarity, increased compatibility between the two phases and uniform distribution of bark fillers in polymers, increased mechanical resistance

The correlation between anthropometric indices and hemodynamic changes after laryngoscopy and endotracheal intubation

Background: Cardiovascular hemodynamic changes after laryngoscopy and endotracheal intubations can cause serious complications. This study was carried out to evaluate the correlation between the anthropometric indices and hemodynamic changes after laryngoscopy and endotracheal intubation (EI). Materials and Methods: This descriptive–analytical pilot study was carried out in 2012, in the Kashani Hospital, Isfahan, Iran. After obtaining written informed consent from 130 patients who fulfilled the inclusion criteria, they were enrolled in the study. The recorded data included were, age, weight, height, neck circumference (NC), waist-to-hip ratio (W/H ratio) and body mass index (BMI). The heart rate (HR), systolic blood pressure (SAP), diastolic blood pressure (DBP), and mean arterial blood pressure (MAP) were recorded at baseline (before injection of the anesthetic drugs), just before laryngoscopy, and one, three, five, and ten minutes after EI. Results: The best cut-off points for BMI, NC, and W/H ratio, for prediction of significant cardiovascular changes after EI were, 26.56 kg/m2, 38 cm, and 0.82, respectively. There was a significant correlation between BMI and HR changes in the first and fifth minutes and also in MAP in the third and fifth minutes after EI (P < 0.05). Moreover, there was a significant correlation between NC and MAP in the fifth minute (P < 0.05). The W/H ratio was significantly related to the DBP in the tenth minute and MAP in the fifth and tenth minutes (P < 0.05). Conclusions: Based on the results of this study, among the anthropometric indices, the BMI, NC, and W/H ratio were significantly correlated with cardiovascular changes after laryngoscopy and tracheal intubation

Evaluation of surface activity of rhamnolipid biosurfactants produced from rice bran oil through dynamic surface tension

Abstract The use of low-cost carbon substrates such as agricultural residues can drastically lower the cost of biosurfactant production. In this study, rice bran oil extracted from agricultural waste was used as a renewable carbon source for biosurfactant production using Pseudomonas aeruginosa PTCC 1340. The biosurfactant was characterized as a glycolipid derivative by thin-layer chromatography and Fourier transform infrared spectroscopy. The yields of biosurfactant from rice bran oil (YRL/S) and biosurfactant to biomass (YRL/X) were 0.246 and 2.81 (g/g), respectively. In addition, the surface activity of the produced biosurfactant was studied using dynamic surface tension measurements and a mono-exponential decay model by estimating the relaxation time of the biosurfactants at the interface. The biosurfactant exhibited acceptable performance in reducing surface tension, as confirmed by examining the dynamic surface tension state and the lowest adsorption time without being affected by the type of salt or concentration. It was found that the adsorption/relaxation of biosurfactants at the interface was considerably affected by the biosurfactant concentration. The produced biosurfactant by the strain considerably reduced the surface tension of water from 70.46 to 25.86 mN/m with a critical micelle concentration (CMC) of 0.09 g/L with rice bran oil as a carbon source. The biosurfactant was also found to be highly effective in suppressing one of the most destructive pathogenic fungi, Macrophomina phaseolina, in terms of its environmental impact. The enhanced physicochemical properties of biosurfactants, such as potential antifungal properties, oil displacement properties, and surface tension-reducing ability, demonstrate the potential of this biosurfactant as a bio-adjuvant and perfect replacement for chemical surfactants in addressing oil spills and environmental decontamination processes