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This paper studies the influence of the leaching conditions on the release of heavy metals, namely lead, zinc iron and copper, from a cementitious material obtained by the solidification of petroleum sludge wastes. Four types of CEM-I-42.5 N based-mortars incorporating.) Petroleum wastes are tested. First, in order to characterize the waste itself, Toxicity Characteristic Leaching Procedure (TCLP), X-ray diffraction (XRD) and Scanning electron microscopy coupled with energy dispersive X-ray microanalysis (SEM-EDX) tests were performed. Secondly, to evaluate the influence of leaching conditions on the release of heavy metals contained in the Stabilized / solidified materials tested, the acid neutralization capacity (ANC), the pore water (PW) and Monolith leaching tests (MLT) were carried out. Leaching tests (ANC, PW and MLT) have shown a low metal leachability. In fact, the lowest released amount was observed for the monolith leaching test (MLT). It was found also that the initial and final setting times increase and the mechanical strength decreases (at 7 days and 28 days age) as the masse percent replacement of cement by petroleum wastes increases. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases, in particular acute coronary syndrome, are the leading cause of death and the rate of hospitalizations. Estimating cardiovascular risk is an important step to initiate primary prevention of this disease. We studied the influence of I883 M variant of the ATP Binding Cassette A1 (ABCA1) gene, which plays a key role in the reverse transport of cholesterol on clinical and lipid parameters in patients with coronary artery disease (CAD) with or without type 2 disease (T2D). Three hundred seventy eight subjects (378) were recruited (95 control, 62 CAD, 58 T2D and 163 CAD + T2D). All were genotyped by PCR-RFLP with EcorV enzyme. Clinical and biochemical parameters were performed using conventional methods. Three genotypes of ABCA-1 were detected: GG mutated homozygote, AG mutated heterozygote and AA, the wild genotype. Results show that the GG genotype was associated to CAD (with or without T2D). AG genotype was associated to hypertriglyceridemia only in T2D group. However, GG genotype was associated to an elevated plasma LDL-C only in CAD group (without T2D) as well as in whole population (n = 378). Our data show that CAD patients with GG genotype are sensitive to develop acute coronary syndrome, probably in association to elevated plasma LDL-C, but independently of type 2 diabetes. [ABSTRACT FROM AUTHOR]

A design of equiangular spiral photonic crystal fiber (PCF) in As2Se3chalcogenide glass is reported for mid-infrared supercontinuum generation. Supercontinuum covering the 1.2–15 μm molecular fingerprint region is achieved using only 8 mm long designed PCF pumped with 50 fs laser pulses of 500 W peak power. The structural parameters have been tailored for all-normal dispersion characteristic. Proposed structure has high nonlinearity (γ = 12474 W−1 km−1) at 3.5 μm with very low and flat dispersion −2.9 [ps/(nm × km)]. Supercontinuum with such broadening and high coherence degree is applicable for mid-infrared spectroscopy, gas sensing, early cancer diagnostics and free space communication. [ABSTRACT FROM AUTHOR]

Studies of the structural, magnetic and magnetocaloric properties of polycrystalline La0.8Ca0.2Mn1-xCoxO3 compounds (0 ≤ x ≤0.3) perovskite manganites were carried out. Samples were synthesized by sol–gel process and then heated at 1000°C for 3 h. X-ray powder diffraction and magnetic measurements were used to investigate the structural and magnetic properties. Rietveld analysis shows that the samples crystallize in the orthorhombic structure with Pnma space group. Crystallographic analysis shows a variation in lattice parameters as cobalt substitution increases, accompanied by a variation in the interatomic distances and a small increase in MT–O–MT angles (MT = cobalt and manganese). Magnetocaloric studies on La0.8Ca0.2Mn1-xCoxO3 compounds with x = 0 and x = 0.2 have been investigated by measuring the magnetization as a function of temperature. At 2 T, the maximum magnetic entropy⎢ΔSmaxM⎢ is about 3.09 J⋅Kg-1⋅K-1 and 1.123 J⋅Kg-1⋅K-1 for x = 0 and 0.2, respectively. Besides, the RCP value decreases with increasing Co content from 55.845 J⋅Kg-1 to 49.971 J⋅Kg-1. Also, the existence of Griffiths Phase and its influence in the phase transition is discussed. [ABSTRACT FROM AUTHOR]

Abstract: The La0.6Pr0.1Sr0.3Mn1−x Fe x O3 (x=0, 0.1, 0.2 and 0.3) samples have been elaborated by the solid-state reaction method. X-ray powder diffraction shows that all the samples crystallize in a rhombohedric phase with space group. The variation of magnetization as a function of temperature and applied magnetic field was carried out. The samples for x=0 and 0.1 exhibit a FM–PM transition at the Curie temperature T C, however, for x=0.2 and 0.3 exhibit an AFM–PM one at the Neel temperature T N, when the temperature increases. A magneto-caloric effect has been calculated in terms of isothermal magnetic entropy change. A large magneto-caloric effect has been observed, the maximum entropy change, , reaches the highest value of 3.28J/kgK under a magnetic field change of 5T with an RCP value of 220J/kg for La0.6Pr0.1Sr0.3MnO3 composition, which will be an interesting compound for application materials working as magnetic refrigerants near room temperature. [Copyright &y& Elsevier]

The effect of three different alkylammonium-modified montmorillonite on morphological and mechanical properties of glassy epoxy-amine nanocomposites is reported. Small amounts of clays <10 phr (part per hundred of resin) were used in each system of nanocomposite. The morphology of the prepared nanocomposites was performed by means of X-ray diffraction and transmission electron microscopy. Differential scanning calorimetry (DSC) was used to investigate the glass transition temperatures ( T g). Mechanical properties were based on tensile characteristics (Young's modulus), impact strength, and fracture toughness. The measured moduli were compared to theoretical predictions. Scanning electron microscopy was used to study the morphological structure of the fracture surfaces of impacted specimens. It was found that at a low content of 2 phr (1.2 wt %) of nanoclays, the impact strength and the fracture toughness were improved by 77 and 90% respectively, comparatively to the neat epoxy, whereas DSC revealed a reduction of the T g of nanocomposites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The objective of this study is to estimate the soil N flux from the vadose zone to the aquifer of the Wilmot watershed (Prince Edward Island, Canada) for a typical three-year cropping rotation (barley-red clover-potato). A conceptual model estimates that 199-221 tons of N were yearly available for leaching at the watershed scale. A significant portion of this N amount was available for leaching at the end of the crop season representing 80-90% of the annual N balance. Drainage water nitrate concentrations were significantly higher after the potato-rotation year than during the crop season. Low nitrate concentrations were measured at spring thaw indicating that most of the nitrate available from the preceding potato crop season was likely leached at the end of fall or during winter. Early spring ionic exchange membrane sampling show a large availability of nitrate in soil possibly throughout winter as well, resulting from soil N mineralization and nitrification over the winter period. These findings are corroborated by the isotope natural abundance analysis of nitrate in groundwater implying that nitrifiers are significantly active during winter, as well as during the crop season, and that leaching of soil nitrates with seasonal signals takes place whenever recharge is occurring. [ABSTRACT FROM AUTHOR]

Understanding the morphological evolution of crystals is crucial for industrial applications and surface engineering. This study employs a multifaceted analytical approach to comprehensively analyze gibbsite, boehmite, η, γ, δ, θ, κ, and α-Al 2 O 3. Density Functional Theory (DFT) surface energy calculations provide essential viewpoints into facet exposure and stability, enriching our comprehension of growth patterns. Using the Bravais–Friedel–Donnay–Harker (BFDH) method, a meticulous investigation into morphological properties reveals equilibrium shapes for each structure. Crucially, our models unveil the inaugural equilibrium shapes for structures previously undocumented in the literature (e.g., η, δ, θ, and κ-Al 2 O 3). The study explores morphological growth process during phase transitions from gibbsite and boehmite to alpha alumina, emphasizing nucleation and dissolution preferences for specific facets. A grain analysis, considering bulk energy, surface area, and volume, designates α-Al 2 O 3 as the most stable phase, offering valuable standpoints on thermodynamics and indicating a direct correlation between facet area and volume. Additionally, a comprehensive 3D surface energy mapping offers intricate visualization of facet interactions, providing valuable viewpoints into the complex relationships between surface energy, facet area, and interplanar distance. Comparisons of Fourier-transform infrared spectroscopy (FTIR) spectra, exclusively within the 200–400 cm-1 range, underscore close agreement between theoretical and experimental spectra, consistent with the expected reduction in specific surface area during polymorphic transformation. [Display omitted] [ABSTRACT FROM AUTHOR]

Studies on the relationship between serum lipid profiles and bone are controversial. We investigated the effect of different lipid profiles on bone parameters in postmenopausal women. A total of 81 postmenopausal women aged 50 years or older were recruited, not including women with a treatment likely to interact with bone metabolism as well as women diagnosed with osteoporosis. According to their lipid profiles, the population was subdivided into women with total dyslipidemia (TD, n = 16), women with only low level of high density lipoprotein cholesterol (L HDL-C, n = 22) and women with normal lipid profiles (N, n = 33). Biochemical analysis was obtained after 12 hours fasting and anthropometric parameters were measured. Bone mineral density (BMD), bone mineral content (BMC), lean and fat mass in different sites were measured by dual-energy X-ray absorptiometry scanning. BMD and T-score of the right femur, left femur, total hip and the whole body (1.18 ± 0.09 vs. 1.12 ± 0.10 g/cm2; 0.98 ± 1.24 vs. 0.18 ± 1.28, P < 0.05) was significantly higher in women with L HDL-C compared to women with normal lipid profiles after adjustment for all possible covariates. In addition, we observed a higher legs BMC in L HDL-C women group compared to women with normal lipid profiles (892.73 vs. 836.62 g, P < 0.05). We hypothesized that low level of HDL-C is associated with elevated BMD and BMC in postmenopausal women and high level of HDL-C may be a risk factor for osteoporosis. However, Further studies are required on larger populations to confirm this hypothesis. [ABSTRACT FROM AUTHOR]

A total of 81 postmenopausal women aged 50 years or older were recruited. Patients with type 2 diabetes mellitus were classified into 3 groups: women on metformin monotherapy (M, n = 20), women on metformin and insulin therapy (M + I, n = 28) and women on insulin monotherapy (I, n = 25). A group of women without treatments of diabetes was included (WT, n = 8). Biochemical analysis was obtained and BMD, BMC, lean and fat mass in different sites were measured by dual-energy X-ray absorptiometry scanning. The results show a significantly higher femoral neck BMD value in women on metformin combined to insulin therapy compared to women on insulin monotherapy after adjustment for all possible covariates. In addition, we observed a higher BMC at the trunk level in women taking metformin drugs compared to those taking insulin combined with metformin treatment, and between women on insulin and metformin drugs compared to those on insulin injection after adjustment. However, there is no significant difference in bone markers concentrations between groups. We hypothesized that only insulin monotherapy is associated to a reduced bone mineral density and content in type 2 diabetic postmenopausal women. [ABSTRACT FROM AUTHOR]

Introduction: Pancreatic neuroendocrine tumors (PanNETs) are often indolent neoplasms without pathological lymph node (LN) metastasis (pN1). Aim(s): To construct a model for predicting the risk of pN1 prior to surgical resection. Materials and methods: The databases from the Surgical Department of the University of Verona and the Beaujon Hospital were queried. Data of 194 patients with resected (R0 or R1), nonfunctioning PanNET (1993-2009) were reviewed. Multiple logistic regression analysis was performed. Results: Metastases were present in the dissected LNs of 58 patients (30%). The 5-year disease free survival for patients with pN1 was significantly lower than for pN0 patients (66% v. 93%, P 4 cm (OR 2.5, P=0.012) was an independent predictor of pN1 (second model). The area under the ROC curve for the first and the second model resulted to be 80% and 74%, respectively. Conclusion: Patients with PanNET-G1, in the absence of radiological node involvement, have a very low risk of pN1. When a preoperative cytological diagnosis is not achieved, then radiological size of the lesion is a powerful alternative predictor of pN1. [ABSTRACT FROM AUTHOR]

B Background: b Pancreaticoduodenectomy (PD) is associated with a high risk of post-operative complications and mortality. The consistence of the pancreas was soft in 147 (82%) patients with PanNENs and in 162 (42%) patients with PDAC (P<0.0001). On multivariate analysis gender (male), PanNENs indication, blood transfusion and "soft" pancreas were independent predictors of PF after PD. [Extracted from the article]

Abstract: The inflammatory myofibroblastic tumour has clinical, biological or histological features sometimes misleading with a septic condition. Presenting symptoms are variable and arising circumstances remain obscure. We report three cases occurring in a postpartum context. The first patient, a 28-year-old female, had left psoitis with a sepsis the first day postpartum in relation with an inflammatory myofibroblastic tumour of the meso-ovary. The second patient, a 40-year-old woman, had a hepatic inflammatory myofibroblastic tumour revealed by a ruptured sub-capsular haematoma of the liver in the forth day postpartum. The third patient, a 32-year-old woman, had a pulmonary inflammatory myofibroblastic tumour, diagnosed 5 months after a delivery and which recurred 10 years after surgical treatment. These cases illustrate the difficulty to diagnose inflammatory myofibroblastic tumour, particularly in postpartum. [ABSTRACT FROM AUTHOR]