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Hydrophobic organic compounds (HOCs) exhibit strong hydrophobicity and low water solubility and are readily adsorbed into soil, which is a complex organic compound. In this study, the adsorption effect and mechanism of 10 soil organic matter components on HOCs (represented by aniline) are studied. Furthermore, a chemical extraction method is used to extract different soil organic components to study their properties and functional groups. The adsorption kinetic experiment is conducted to determine the equilibrium time of aniline. The isothermal adsorption experiment is conducted to determine the isothermal adsorption model of aniline and explore its characteristics. Results show that different components have various physical and chemical properties. The pseudo-quadratic kinetic model fitted well with experimental data, indicating that the adsorption of aniline reached equilibrium within 24 h. The Freundlich model fits the isotherm adsorption data of aniline, revealing that the adsorption capacity is significantly positively correlated with the organic carbon content and specific surface area. This study shows that humic acid 2 has the best adsorption capacity for aniline. This study enables the prediction of environmental risks posed by HOCs such as aniline. [ABSTRACT FROM AUTHOR]

Polyaniline (PAni) thin films were prepared by using an electrochemical polymerization technique on glass/FTO substrates by varying the deposition potential, deposition time, pH concentrations and heat treatment conditions. The structural, morphological, optical and electrical properties of electrodeposited PAni films were characterized using x-ray diffraction, scanning electron microscopy, UV-VIS spectroscopy, optical profilometry and D.C. conductivity measurements. Structural analysis shows the formation of the highest crystallinity for PAni thin film grown at V 1654 mV. Optical absorption measurements have demonstrated a wide variety of energy band gaps ( E), varying from ∼0.50 eV to 2.40 eV for PAni grown by tuning the pH value during the deposition. The electrical resistivity showed an increase from 0.37 × 10 Ω cm to 3.91 × 10 Ω cm when the pH increased from 2.00 to 6.50. The diode structures of glass/FTO/CdS/CdTe/PAni/Au were fabricated incorporating PAni as a pinhole plugging layer, and assessed for their photovoltaic activities. The results showed the enhancement of all device parameters, especially of open circuit voltage and fill factors. This improvement offers a great potential for enhancing solar cell performance and the device lifetime, and the latest results are presented in this paper. [ABSTRACT FROM AUTHOR]

Indium Selenide (InSe) layers were potentiostatically deposited on glass/fluorine-doped tin oxide (FTO) substrates, using electro-chemical technique from aqueous solution containing 0.10 M InCl and 0.02 M SeO. The electrodeposits were characterised using a wide range of analytical techniques; X-ray diffraction (XRD), scanning electron microscopy (SEM), Atomic force microscopy (AFM), optical absorption and photoelectrochemical (PEC) cell, for their structural, morphological, optical and electrical properties. The XRD show that the prepared films consist of mixed phases of InSe and InSe. The films grown at all voltages in this work were p type in electrical conduction, with bandgaps in the range of (1.70-1.80) eV in both as-deposited and heat-treated forms. The wetting property of InSe on glass/FTO surfaces indicates that InSe layers can be helpful as buffer layers or window layers in thin film solar cell development due to their ability to uniformly cover the substrate. The cross-section morphology show smoothening effect of these layers. The experimental results to date are presented in this paper. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Evaluation of the association of 31 common single nucleotide polymorphisms (SNPs) with fasting glucose, fasting insulin, HOMA-beta cell function (HOMA-β), HOMA-insulin resistance (HOMA-IR) and type 2 diabetes in the Indian population. Methods: We genotyped 3,089 sib pairs recruited in the Indian Migration Study from four cities in India (Lucknow, Nagpur, Hyderabad and Bangalore) for 31 SNPs in 24 genes previously associated with type 2 diabetes in European populations. We conducted within-sib-pair analysis for type 2 diabetes and its related quantitative traits. Results: The risk-allele frequencies of all the SNPs were comparable with those reported in western populations. We demonstrated significant associations of CXCR4 (rs932206), CDKAL1 (rs7756992) and TCF7L2 (rs7903146, rs12255372) with fasting glucose, with β values of 0.007 ( p = 0.05), 0.01 ( p = 0.01), 0.007 ( p = 0.05), 0.01 ( p = 0.003) and 0.08 ( p = 0.01), respectively. Variants in NOTCH2 (rs10923931), TCF-2 (also known as HNF1B) (rs757210), ADAM30 (rs2641348) and CDKN2A/B (rs10811661) significantly predicted fasting insulin, with β values of −0.06 ( p = 0.04), 0.05 ( p = 0.05), −0.08 ( p = 0.01) and −0.08 ( p = 0.02), respectively. For HOMA-IR, we detected associations with TCF-2, ADAM30 and CDKN2A/B, with β values of 0.05 ( p = 0.04), −0.07 ( p = 0.03) and −0.08 ( p = 0.02), respectively. We also found significant associations of ADAM30 ( β = −0.05; p = 0.01) and CDKN2A/B ( β = −0.05; p = 0.03) with HOMA-β. THADA variant (rs7578597) was associated with type 2 diabetes (OR 1.5; 95% CI 1.04, 2.22; p = 0.03). Conclusions/interpretation: We validated the association of seven established loci with intermediate traits related to type 2 diabetes in an Indian population using a design resistant to population stratification. [ABSTRACT FROM AUTHOR]

A prospective crossover study of 35 patients was performed to investigate the effect of a filling catheter upon closure pressure, functional length, and total urethral length. Urethral pressure profiles were done while the patients were in the sitting position with a full bladder, both with and without a 6 F pediatric feeding tube in the urethra. Both closure pressure and functional length were significantly higher with the filling catheter in situ. Urethral pressure profiles were different in all patients with the filling catheter in place. Urethral pressure profiles and cystometrograms should be done without filling catheters, using the smallest microtransducer catheters available, to avoid artifactual effects. [ABSTRACT FROM AUTHOR]

Synthetic aluminum-substituted maghemite samples, γ-(AlFe)O with y=0, 0.032, 0.058, 0.084, 0.106 and 0.151 have been studied by Mössbauer spectroscopy at 8 K and in the range 80 K to 475 K at steps of 25 K. The spectra have been analysed as a superposition of two sextets composed of asymmetrical Lorentzians. The A- and B-site isomer shifts were constrained as: δ=δ-0.12 mm/s. From the temperature dependence of δ it was possible to determine the c haracteristic Mössbauer temperature and the intrinsic shift. Both quantities clearly increase with increasing Al content, at least up to 10 mole%. The temperature dependence of the A-and B-sites hyperfine fields could be satisfactorily reproduced using the molecular-field theory assuming an antiparallel spin configuration. The exchange integrals were found as: J=-25 K; J=-18 K and J= -3 K. The hyperfine fields show a crossing in the vicinity of 300 K as a result of the relatively strong A-A interaction. The Curie temperature for the non-substituted sample was calculated to be 930 K and decreases to 765 K for the sample with 15 mol% Al. The gradual decrease of the saturation value of the A-site hyperfine field with increasing Al substitution and the constancy of this quantity for the B sites, suggest that the Al cations occupy the B sites. [ABSTRACT FROM AUTHOR]

The lepidocrocite (γ-FeOOH) to maghemite (γ-FeO), and the maghemite to hematite (α-FeO) transition temperatures have been monitored by TGA and DSC measurements for four initial γ-FeOOH samples with different particle sizes. The transition temperature of γ-FeOOH to γ-FeO and the size of the resulting particles were not affected by the particle size of the parent lepidocrocite. In contrast, the γ-FeO to γ-FeO transition temperature seems to depend on the amount of excess water molecules present in the parent lepidocrocite. Thirteen products obtained by heating for one hour at selected temperatures, were considered. Powder X-ray diffraction was used to qualify their composition and to determine their mean crystallite diameters. Transmission electron micrographs revealed the particle morphology. The Mössbauer spectra at 80 K and room temperature of the mixed and pure decomposition products generally had to be analyzed with a distribution of hyperfine fields and, where appropriate, with an additional quadrupole-splitting distribution. The Mössbauer spectra at variable temperature between 4.2 and 400 K of two single-phase γ-FeO samples with extremely small particles show the effect of superparamagnetism over a very broad temperature range. Only at the lowest temperatures (T⩽55 K), two distributed components were resolved from the magnetically split spectra. In the external-field spectra the Δm=0 transitions have not vanished. This effect is an intrinsic property of the maghemite particles, indicating a strong spin canting with respect to the applied-field direction. The spectra are successfully reproduced using a bidimensional-distribution approach in which both the canting angle and the magnetic hyperfine field vary within certain intervals. The observed distributions are ascribed to the defect structure of the maghemites (unordered vacancy distribution on B-sites, large surface-to-bulk ratio, presence of OH groups). An important new finding is the correlation between the magnitude of the hyperfine field and the average canting angle for A-site ferric ions, whereas the B-site spins show a more uniform canting. The Mössbauer parameters of the two hematite samples with MCD values of respectively 61.0 and 26.5 nm display a temperature variation which is very similar to that of small-particle hematites obtained from thermal decomposition of goethite. However, for a given MCD the Morin transition temperature for the latter samples is about 30 K lower. This has tentatively been ascribed to the different mechanisms of formation, presumably resulting in slightly larger lattice parameters for the hematite particles formed from goethite, thus shifting the Morin transition to lower temperatures. [ABSTRACT FROM AUTHOR]

Celadonite from the northwestern Mojave Desert area of California was examined by detailed Mössbauer spectroscopy at temperatures from 10 K to 400 K. In addition to the predominant Fe doublet with isomer shift δ∼0.4 mm s and quadrupole splitting Δ ∼ 0.4 mm s, another Fe doublet with δ∼ 0.4, Δ∼1.2 mm/s and two Fe doublets with δ∼1.1, Δ ∼ 1.7, 2.7 mm s at 300 K were distinguished. The minor Fe component is ascribed to dehydroxylated surface sites. Most of the remaining Fe(∼90%) is M2 cis-OH octahedral in an ordered M−M array. However, about 10% is M1 trans-OH Fe. Isomer shift vs. T gives Debye temperatures of 570 K for Fe in M2 and 380 K for both Fe sites, indicating greater vibrational freedom for Fe. Quadrupole splitting Δ vs. T for Fe gives a valence electronic energy splitting of 760 cm between the ground and first excited state for M2. The M1 sites have a more drastic variation in Δ vs. T which indicates not only a lower first excited state but a rhombic distortion at these sites. A proposed explanation is a neighboring M2 site vacancy. The soil clay formed from this celadonite, which is mostly Fe-rich smectite, was also studied by Mössbauer spectroscopy. About half the Fe has been oxidized in the clay, but the isomer shifts and quadrupole splittings are essentially the same as in the original celadonite. A texture orientation in the clay absorber was detected by measuring the absorber at 55° to the source radiation. This texture effect produces asymmetric doublets in the usual 90° measurement. [ABSTRACT FROM AUTHOR]

Four synthetic lepidocrocite samples with a significant difference in crystallinity have been studied by the Fe Mössbauer effect technique at temperatures ranging between 12 K and 360 K. In the magnetically ordered region, the spectra display broad hyperfine field distributions, the profile of which could be derived numerically. In a broad transition region of approximately 20 K, an additional doublet must be included in the fitting model. From Mössbauer thermoscanning measurements at zero-velocity and with and without the application of an external magnetic field, it is found that the doublet is due to Fe species in a paramagnetic state. Neither the hyperfine field nor the Néel temperature distributions are markedly affected by the crystallinity. In the pure paramagnetic state, the broadened doublets are best described by a distribution of quadrupole splittings in the range 0.3-1.9 mm/s. By numerical manipulations of the derived probability profiles it was possible to distinguish between the iron species in the outer surface layers of the γ-FeOOH particles and those in the innermost layers, the relative amount of each being correlated with the measured surface areas. The centre shift is quite uniform and its temperature dependence, determined in detail for one of the samples, is perfectly described by the Debije approximation for the second-order Doppler shift. From the obtained Debije temperature, a Mössbauer fraction f of 0.79 at room temperature was calculated, which is in good agreement with the results obtained for a reference lepidocrocite/hematite mixture. Finally, line shape simulations aimed to explain the external field spectrum at 180 K provided strong indications that both the sign and the asymmetry parameter of the electric field gradient are non-uniform as well. [ABSTRACT FROM AUTHOR]

In a 24-month prospective study, 22 patients with documented papillomavirus lesions elsewhere in the lower genital tract underwent biopsy of the urothelium of the urethra. These patients met the accepted criteria for urethral syndrome. The specimens were obtained under colposcopic control with small tissue biopsy forceps inserted through a modified Kelly air cystoscope. Polymerase chain reaction amplification and subsequent DNA primer evaluation failed to reveal the presence of papillomavirus infection in 20 of the 22 patients. Differentiated squamous mucosa was found on morphologic studies from these biopsies in 18 instances (82%). This multicenter study was unable to document the presence of human papillomavirus infection of the proximal urethral vesical neck or bladder trigone. [ABSTRACT FROM AUTHOR]