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The production of biodiesel as a fuel in diesel engines greatly increased in recent years and is expected to grow more and more in the near future. Increasing biodiesel consumption requires optimized production processes allowing high production capacities, simplified operations, high yields, and the use of more economic feedstocks such as waste oils and fats. However, the latter often contain large amounts of free fatty acids and cannot be processed with the commonly practiced technology based on the use of alkaline catalysts in the homogeneous phase that requires the use of highly refined oil as raw materials. Therefore, the development of processes for low-cost biodiesel production requires the individuation of heterogeneous catalysts that are very efficient in promoting the transesterification reaction also in the presence of free fatty acids and water, allowing the prompt separation of pure glycerol and not requiring expensive purification of this byproduct. In the present contribution, the performances of different heterogeneous catalysts are compared both in the absence and in the presence of free fatty acids. In some cases, the resistance of the catalysts to the presence of water and the eventual deactivating effects after the first use have also been tested. The catalysts considered are both basic and acidic in nature, such as hydrotalcite, MgO, TiO2grafted on silica, vanadyl phosphate, and different metals-substituted vanadyl phosphate of the type Me(H2O)xVO1-xPO4·2H2O, where Me is a trivalent cation such as Al, Ga, Fe, and Cr and where x0.18−0.20. Finally, the understanding of the kinetic behavior of the most stable catalyst TiO2/SiO2has been deepened. [ABSTRACT FROM AUTHOR]

To test the association of osteopontin (OPN) polymorphisms with systemic lupus erythematosus (SLE).The coding 5′ and 3′ flanking regions of the OPN gene were scanned for polymorphisms by denaturing high‐performance liquid chromatography. A case–control association study was performed in 394 Italian SLE patients and 479 matched controls. OPN serum levels were determined by enzyme‐linked immunosorbent assay in 40 patients and 124 controls, and the mean levels were compared between the different OPN genotypes.Among the 13 detected single‐nucleotide polymorphisms (SNPs), alleles −156G (frequency 0.714 versus 0.651; P = 0.006, corrected P [Pcorr] = 0.036) and +1239C (0.377 versus 0.297; P = 0.00094, Pcorr = 0.0056) were significantly increased in the SLE patients compared with the controls. The presence of the associated allele in single or double dose conferred an odds ratio (OR) of 2.35 (95% confidence interval [95% CI] 1.38–4.02) for SNP −156 and an OR of 1.57 (95% CI 1.16–2.13) for SNP +1239. These effects were independent of each other, i.e., not a consequence of linkage disequilibrium between the 2 alleles. The risk associated with a double dose of susceptibility alleles at both SNPs was 3.8‐fold higher (95% CI 2.0–7.4) relative to the complete absence of susceptibility alleles. With regard to individual clinical and immunologic features, a significant association was seen between lymphadenopathy and −156 genotypes (overall P = 0.0011, Pcorr = 0.046). A significantly increased OPN serum level was detected in healthy individuals carrying +1239C (P = 0.002), which is indicative of an association between the SLE susceptibility allele and OPN levels.These data suggest the independent effect of a promoter (−156) and a 3′‐untranslated region (+1239) SNP in SLE susceptibility. We can speculate that these sequence variants (or others in perfect linkage disequilibrium) create a predisposition to high production of OPN, and that this in turn may confer susceptibility to SLE. [ABSTRACT FROM AUTHOR]

BACKGROUND Among subjects with endometriosis and deep dyspareunia (DD), those with endometriosis of the uterosacral ligament (USLE) have the most severe impairment of sexual function. This study examines the effect of laparoscopic excision of endometriosis on DD and quality of sex life. METHODS This observational cohort prospective study included 68 women with endometriosis suffering DD (intensity of pain ≥ 6 on a 10-cm visual analogue scale). Patients underwent laparoscopic full excision of endometriosis. Following surgery, they were asked to use nonhormonal contraception devices. Before surgery, at 6- and at 12-month follow-up, patients answered a self-administered questionnaire based on the Sexual Satisfaction Subscale of the Derogatis Sexual Functioning Inventory. RESULTS At 6- and 12-month follow-up, women with and without USLE had significant improvement in DD. Subjects with USLE reported increased variety in sex life, increased frequency of intercourse, more satisfying orgasms with sex, relaxing more easily during sex and being more relaxed and fulfilled after sex. Similar improvements were observed among women without USLE; however, for some variables statistical significance was not reached. CONCLUSIONS Surgical excision of endometriosis improves not only DD but also the quality of sex life. [ABSTRACT FROM AUTHOR]

We present a sample of X-ray-selected candidate black holes in 51 low-mass galaxies with z ≤ 0.055 and masses up to 1010M⊙ obtained by cross-correlating the NASA-SLOAN Atlas with the 3XMM catalog. We have also searched in the available catalogs for radio counterparts of the black hole candidates and find that 19 of the previously selected sources also have a radio counterpart. Our results show that about 37% of the galaxies of our sample host an X-ray source (associated with a radio counterpart) spatially coincident with the galaxy center, in agreement with other recent works. For these nuclear sources, the X-ray/radio fundamental plane relation allows one to estimate the mass of the (central) candidate black holes, which are in the range of 104–2 × 108M⊙ (with a median value of ≃3 × 107M⊙ and eight candidates having masses below 107M⊙). This result, while suggesting that X-ray emitting black holes in low-mass galaxies may have had a key role in the evolution of such systems, makes it even more urgent to explain how such massive objects formed in galaxies. Of course, dedicated follow-up observations both in the X-ray and radio bands, as well as in the optical, are necessary in order to confirm our results. [ABSTRACT FROM AUTHOR]

In gravitational microlensing, binary systems may act as lenses or sources. Identifying lens binarity is generally easy, in particular in events characterized by caustic crossing since the resulting light curve exhibits strong deviations from a smooth single-lensing light curve. In contrast, light curves with minor deviations from a Paczyński behavior do not allow one to identify the source binarity. A consequence of gravitational microlensing is the shift of the position of the multiple image centroid with respect to the source star location — the so-called astrometric microlensing signal. When the astrometric signal is considered, the presence of a binary source manifests with a path that largely differs from that expected for single source events. Here, we investigate the astrometric signatures of binary sources taking into account their orbital motion and the parallax effect due to the Earth’s motion, which turn out not to be negligible in most cases. We also show that considering the above-mentioned effects is important in the analysis of astrometric data in order to correctly estimate the lens-event parameters. [ABSTRACT FROM AUTHOR]