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In this work we state conditions for a current Lie algebra g ⊗ S to admit an invariant metric, where g is a quadratic Lie algebra and S is an associative and commutative algebra with unit. We show that if g is an indecomposable quadratic Lie algebra, then g ⊗ S admits an invariant metric if and only if S also admits an invariant metric. In addition, we prove a theorem similar to the double extension for g ⊗ S , where g is an indecomposable, nilpotent and quadratic Lie algebra. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to show that there are Hom-Lie algebra structures on s l 2 (F) ⊕ F D , where D is a special type of generalized derivation of s l 2 (F) , and F is an algebraically closed field of characteristic zero. We study the representation theory of Hom-Lie algebras within the appropriate category and prove that any finite dimensional representation of a Hom-Lie algebra of the form s l 2 (F) ⊕ F D is completely reducible, analogously to the well-known theorem of Weyl from the classical Lie theory. We apply this result to characterize the non-solvable Lie algebras of this type having an invertible generalized derivation D. [ABSTRACT FROM AUTHOR]

A quadratic Lie algebra is a Lie algebra endowed with a symmetric, invariant and nondegenerate bilinear form; such a bilinear form is called an invariant metric. The aim of this work is to describe the general structure of those central extensions of quadratic Lie algebras which in turn have invariant metrics. The structure is such that the central extensions can be described algebraically in terms of the original quadratic Lie algebra, and geometrically in terms of the direct sum decompositions that the invariant metrics involved give rise to. [ABSTRACT FROM AUTHOR]

In this work, we show that the existence of invertible generalized derivations impose strong restrictions on the structure of a complex finite-dimensional Lie algebra. In particular, we recover the fact that a real Lie algebra admitting an abelian complex structure is necessarily solvable. On the other hand, we state a structure theorem for a Lie algebra 𝔤 admitting a periodic generalized derivation D ∈ Der (− 1 , 1 , 1) (𝔤). [ABSTRACT FROM AUTHOR]

Given an involution φ : G → G in a group G and a ring R, we study the extensions, not necessarily linear, to an involution ψ : RG → RG in the group ring RG. We investigate the symmetric elements, those α ∈ RG for which ψ(α) = α, and give necessary and sufficient conditions for the set of symmetric elements, (RG)ψ, to be a subring of RG. This work is a generalization of [6] and references therein where only linear extensions of the group involution are considered. [ABSTRACT FROM AUTHOR]

There is barely any information about the prognostic significance of FLT3 expression and mutational status in cytogenetically distinct subgroups of acute lymphoblastic leukemia (ALL). We analyzed the presence of FLT3-tyrosine kinase domain (TKD) and FLT3-internal tandem duplication (ITD) mutations as well as FLT3 expression levels in 54 newly diagnosed patients with B-ALL (n=49) or T-ALL (n=5). All B/T-ALL samples tested negative for the presence of FLT3-TKD or FLT3-ITD. None of the T-ALL and E2A-PBX1+ B-ALL overexpressed FLT3. In contrast, mainly MLL-AF4+ B-ALL but also ETV6-RUNX1+, BCR-ABL+ or B-ALL displaying normal cytogenetics exhibited significantly higher FLT3 expression levels than normal bone marrow, supporting that aberrantly increased transcription of FLT3, rather than activating FLT3 mutations, contributes to the pathogenesis of these B-ALL. Using the median FLT3 expression as cut-off value we found that high-level FLT3 expression is associated with an extremely poor 1-year overall survival (OS; 0 vs 71%; P=0.002) and disease-free survival (DFS; 0 vs 43%; P=0.03) in MLL-AF4+ B-ALL but not in MLL-germline B-ALL. Cox regression analysis with OS/DFS as end points showed that age>14 years and high-level FLT3 expression were independent prognostic factors when all ALL patients were analyzed together. Importantly, when the MLL-AF4+ B-ALL subgroup was analyzed separately, high-level FLT3 expression was the only independent prognostic factor for OS and treatment outcome. These findings indicate that high FLT3 expression identifies MLL-AF4+ ALL patients at very high risk of treatment failure and poor survival, emphasizing the value of ongoing/future clinical trials for FLT3 inhibitors. [ABSTRACT FROM AUTHOR]

Objectives The aim of the study was to determine the factors that may contribute to decreases in bone mineral density (BMD) in patients with AIDS. Methods This was a prospective, non-randomized study. Dual X-ray absorptiometry (DXA) was used to determine the BMD of the lumbar spine, femoral neck and distal radius in treatment-naïve HIV-infected male patients with AIDS before and after 1 year of treatment with zidovudine (ZDV)/lamivudine (3TC) plus abacavir (ABC) or lopinavir/ritonavir (LPV/r). Results Basal DXA was performed in 50 patients with CD4 counts <200 cells/μL and/or any AIDS-defining condition. Thirty-two patients completed 1 year with full adherence (17 on ABC and 15 on LPV/r) and a second DXA was then performed. At baseline, 19% had osteopenia at the lumbar spine and 19% at the femoral neck. Low body weight was related to low BMD. After 48 weeks, BMD loss was significant at the three locations. The percentage of BMD loss at the femoral neck tended to be greater in the lopinavir group (5.3 vs. 3.2%, P=0.058). The differences became significant at the lumbar spine (5.7 vs. 2.7%, P=0.044). In the multivariate analysis, the treatment with LPV/r remained associated with bone loss at the lumbar spine. Conclusions Osteopenia is frequent in treatment-naïve HIV-infected men with AIDS. Bone loss is higher with LPV/r-based regimens compared with triple nucleoside reverse transcriptase inhibitors. [ABSTRACT FROM AUTHOR]

The influence of soil carbonate content on the fate of lead in soil was studied in a lab-scale column under different pH values of the contaminant solution. Results indicated that retention of this toxic heavy metal (up to 38% weight at pH = 5) occurred which was proportional to the total carbonate content. A decrease in the pH of the aqueous solution entering the column resulted in a decrease of the retention of lead in the soil. Furthermore, the concentration of lead in the effluent was increased dramatically. Concentrations of lead about 2.5 times higher than in the contaminant solution were measured at pH = 3. Knowledge of these phenomena is important for risk assessment and remediation feasibility studies. [ABSTRACT FROM AUTHOR]

As SVE proceeds large amounts of water are withdrawn from the soil with the gaseous stream together with the contaminants. This may lead to important variations in the pneumatic soil permeability and changes in the soil temperature. A one-dimensional column mathematical model is developed to study these effects, based on the Millington and Quirk expression and assuming local thermal equilibrium and fast water mass transfer from the condensed to the gaseous phase. This model yields a good agreement with experimental results obtained with fine-sand lab columns. The molar flux increases during the process, but most of this increase takes place during the latter period of the drying process. Important temperature drops (up to 10 °C) are also expected when relative moisture of the air is low. [ABSTRACT FROM AUTHOR]

The need to maintain long-term treatment of chronic pathologies makes the appearance of interactions possible when such therapies incorporate other drugs to deal with the aggravation of the same or other intercurrent pathologies. A case is presented in which the addition of trazodone to a chronic treatment with carbamazepine (CBZ) is associated with symptoms typical for intoxication by this antiepileptic, accompanied by a raised serum concentration. When the trazodone was suspended, these symptoms lessened and the concentration of CBZ decreased progressively, suggesting a probable interaction between the 2 drugs. [ABSTRACT FROM AUTHOR]