Three novel vanadogermanate cluster anions have been synthesized by hydrothermal reactions. The cluster anions are derived from the (V(18)O(42)) Keggin cluster shell by substitution of V=O(2+) "caps" by Ge(2)O(OH)(2)(4+) species. In Cs(8)[Ge(4)V(16)O(42)(OH)(4)].4.7H(2)O, 1, (monoclinic, space group C2/c (No. 15), Z = 8, a = 44.513(2) A, b = 12.7632(7) A, c = 22.923(1) A, beta = 101.376(1) degrees ) and (pipH(2))(4)(pipH)(4)[Ge(8)V(14)O(50).(H(2)O)] (pip = C(4)N(2)H(10)), 2 (tetragonal, space group P4(2)/nnm (No. 134), Z = 2, a = 14.9950(7) A, c = 18.408(1) A), two and four VO(2+) caps are replaced, respectively, and each cluster anion encapsulates a water molecule. In K(5)H(8)Ge(8)V(12)SO(52).10H(2)O, 3, (tetragonal, space group I4/m (No. 87), Z = 2, a = 15.573(1) A, c = 10.963(1) A), four VO(2+) caps are replaced by Ge(2)O(OH)(2)(4+) species, and an additional two are omitted. The cluster ion in 3 contains a sulfate anion disordered over two positions. The cluster anions are analogous to the vanadoarsenate anions [V(18)(-)(n)()As(2)(n)()O(42)(X)](m)(-) (X = SO(3), SO(4), Cl; n = 3, 4) previously reported.
Since the days of Pauling it has been tacitly assumed that the valence, which is distributed between the bonds to neighbouring atoms, is the stoichiometric valence, (stoich)V, which has integer values. It is shown here that this is not true. Instead, bond-valence sums (BVS) calculated for lanthanide (Ln) atoms of a series of garnet-type compounds Ln(3)(III)Te(2)(VI)Li(3)(I)O(12) deviate significantly from (stoich)V. Values of (BVS)(Ln) of this series, plotted versus the element number Z(Ln), show the same irregular sequence as: (i) the third ionization potentials of Ln atoms, (ii) the valence values previously calculated with quantum-chemical methods for lanthanide metals and sulfides, and (iii) the experimental efficiencies of the reactions between Ln(I) and SF(6) in the gas phase. This indicates that in the Ln(3)Te(2)Li(3)O(12) series the BVS values of the Ln atoms, which are ;rattling' in rather large and rigid voids of the structure, reflect the electronic structure of Ln. It is, therefore, concluded that BVS represent a non-integer valence, which is based on the electronic structure of bonded atoms, rather than (stoich)V. For this non-integer valence the term ;structural valence' and the symbol (struct)V have been proposed. In another series of lanthanide chelates the (BVS)(Ln) values deviate even more from (stoich)V(Ln) = 3 v.u. than in the garnet-type series. In the chelates the Ln atoms are ;squeezed' in rather small voids so that the electronic effects of Ln acting on (BVS)(Ln) are overridden by stronger steric effects exerted by the organic ligands.
OBJECTIVES: To compare 12-month adherence to liraglutide once daily (QD) or exenatide once weekly (QW) between commercially insured patients with type 2 diabetes mellitus (T2DM) newly initiating liraglutide QD or exenatide QW in the U.S. METHODS: This retrospective cohort study used U.S. administrative claims data to study patients with T2DM initiating liraglutide QD or exenatide QW (initiated therapy= index therapy). Patients were included if they had T2DM, were glucagonlike peptide-1 receptor agonist (GLP-1RA)-naïve, initiated liraglutide QD or exenatide QW from 2/1/2012-10/1/2012 (date of initiation= index), were aged ≥ 18y at index, and had continuous enrollment for 12 months before (baseline) to 12 months after index (follow-up). The study outcome was index GLP-1RA adherence (proportion of days covered [PDC] during follow-up, dichotomized at ≥ 80% versus < 80%, and at ≥ 90% versus < 90%). These PDC thresholds have been shown to be predictive of reduced hospitalization and mortality for patients with diabetes. Multivariable logistic regressions compared adherence between the GLP-1RAs, adjusting for potential confounders. Sensitivity analyses were performed separating liraglutide QD by dose (1.2 mg/1.8 mg). RESULTS: Study sample included 10,829 liraglutide QD (4,945 1.2 mg; 5,884 1.8 mg) patients and 3,173 exenatide QW patients. In each group, mean age was approximately 52 years and the proportion of females was 50% for exenatide QW and 54% for liraglutide QD. In multivariable-adjusted analyses, liraglutide QD patients had statistically significant lower odds of achieving a PDC≥ 80% (odds ratio [OR] treating exenatide QW as reference= 0.888, P= .007, 95% confidence interval [CI]= 0.816 to 0.968) and statistically significant lower odds of achieving a PDC≥ 90% (OR= 0.757, P< .001, 95% CI= 0.690 to 0.831) than exenatide QW patients. In sensitivity analyses, results when separating liraglutide QD by dose were directionally consistent. CONCLUSIONS: Patients receiving exenatide QW had greater adjusted odds of clinically significant adherence thresholds compared with patients receiving liraglutide QD in this retrospective analysis.OBJECTIVES: To assess the barriers to treatment adherence on disease management of acromegaly from the provider prospective METHODS: A web-based crosssectional survey was conducted from August -October, 2014. Healthcare providers who had experience in treating acromegaly patients were asked about barriers to treatment adherence and influence on the treatment algorithm based on their experiences and perspectives. RESULTS: A total of 23 providers (mean age: 56 years, female: 48%) completed the survey, including physicians (52%), nurses or nurse practitioners (43%) and research coordinators (5%). Most worked at academic hospitals (78%). Their specialties included endocrinology & metabolism (70%), neuroendocrinology (22%) and neurosurgery (8%). Of the providers, 62% had more than 10 years of experience (range: 5-40 years) treating acromegaly; 75% of them were concerned about the barriers to ...
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