Polymeric aqua(glutarato)(hydrogen glutarato)lanthanum(III) monohydrate

The structure of the title compound, [La(C5H6O4)(C5H7O4)(H2O)] . H2O, consists of dense layers formed by chains of one-edge-sharing LaO9 (H2O) polyhedra, linked together by the glutarate ligand. The three-dimensional polymeric structure, built up through connection of these layers by the hydrogen glutarate ligand, exhibits cavities accommodating a guest water molecule. The lanthanum ion is tenfold coordinated by four glutarates, acting as bridging-chelating carboxylate groups, by three hydrogen glutarates, three times monodentate, and by one water molecule. Its coordination polyhedron is highly distorted and intermediate between a bicapped dodecahedron and a tetracapped trigonal prism. Hydrogen bonding links the two water molecules and the framework built up from this polynuclear coordination polymer. A very short hydrogen bond, D ... A = 2.484 (3) Angstrom, links the protonated with the deprotonated acid groups in the hydrogen glutarate. [References: 12] 1

Studies of two lanthanide coordination polymers built up from dinuclear units

International audienceThe two three-dimensional oxo-bridged lanthanides \[Ln(2) (C4H2O4)(3) (H2O)(4)]center dot 3H(2)O\(3)(proportional to), with Ln=Ho3+ (1); Gd3+ (2), are isomorphous. They have layer-type structures built up from non-centrosymmetric dinuclear unit Ln(2)O(12)(H2O)(4), beside three lattice H2O molecules stabilizing the 3D open-framework. The building entities are linked through one classical syn-anti mu 2-carboxylato-(KO)-O-1:(KO)-O-1' bridge. Within the bi-polyhedra, two double mu 2-O';(KO)-O-2,O' bridges and a syn-syn classical one, support the magnetic measurements carried out on holmium compound indicating relatively weak anti-ferromagnetic interactions. The comparison with magnetic studies on the almost similar reported Gd(III) compound, suggested that concomitant antiferromagnetic and ferromagnetic properties could not be excluded. The two distinct thermal behaviors evidenced the higher metal-water bond strength with the smaller cation, and revealed the great supramolecular effects generated by hydrogen-bonding patterns

Long-term air pollution exposure is associated with increased severity of rhinitis in 2 European cohorts

Background: Very few studies have examined the association between long-term outdoor air pollution and rhinitis severity in adults. Objective: We sought to assess the cross-sectional association between individual long-term exposure to air pollution and severity of rhinitis. Methods: Participants with rhinitis from 2 multicenter European cohorts (Epidemiological Study on the Genetics and Environment on Asthma and the European Community Respiratory Health Survey) were included. Annual exposure to NO2, PM10, PM2.5, and PMcoarse (calculated by subtracting PM2.5 from PM10) was estimated using land-use regression models derived from the European Study of Cohorts for Air Pollution Effects project, at the participants' residential address. The score of rhinitis severity (range, 0-12), based on intensity of disturbance due to symptoms reported by questionnaire, was categorized into low (reference), mild, moderate, and high severity. Polytomous logistic regression models with a random intercept for city were used. Results: A total of 1408 adults with rhinitis (mean age, 52 years; 46% men, 81% from the European Community Respiratory Health Survey) were included. The median (1st quartile-3rd quartile) score of rhinitis severity was 4 (2-6). Higher exposure to PM10 was associated with higher rhinitis severity (adjusted odds ratio [95% CI] for a 10 μg/m3 increase in PM10: for mild: 1.20 [0.88-1.64], moderate: 1.53 [1.07-2.19], and high severity: 1.72 [1.23-2.41]). Similar results were found for PM2.5. Higher exposure to NO2 was associated with an increased severity of rhinitis, with similar adjusted odds ratios whatever the level of severity. Adjusted odds ratios were higher among participants without allergic sensitization than among those with, but interaction was found only for NO2. CONCLUSIONS: People with rhinitis who live in areas with higher levels of pollution are more likely to report more severe nasal symptoms. Further work is required to elucidate the mechanisms of this association.The following bodies funded the local studies in ECRHS III in this article: Belgium: Antwerp South, Antwerp City: Research Foundation Flanders (FWO), grant code G.0.410.08.N.10 (both sites); France: Ministère de la Santé , Programme Hospitalier de Recherche Clinique (PHRC) national 2010; Germany: Erfurt: German Research Foundation ( HE 3294/10-1 ); Spain: Fondo de Investigación Sanitaria ( PS09/02457 , PS09/00716 09/01511 , PS09/02185 , and PS09/03190 ), Servicio Andaluz de Salud, Sociedad Española de Neumología y Cirurgía Torácica ( SEPAR 1001/2010 ); Barcelona: Fondo de Investigación Sanitaria ( FIS PS09/00716 ); Galdakao: Fondo de Investigación Sanitaria ( FIS 09/01511 ); Huelva: Fondo de Investigación Sanitaria ( FIS PS09/02185 ) and Servicio Andaluz de Salud ; Oviedo: Fondo de Investigación Sanitaria ( FIS PS09/03190 ); United Kingdom: Medical Research Council (grant no. 92091 ). The Epidemiological Study on the Genetics and Environment on Asthma is funded in part by PHRC-Paris, PHRC-Grenoble, ANR 05-SEST-020-02/05-9-97, ANR-06-CEBS, ANR-CES-2009, Région Nord Pas-de-Calais, and Merck Sharp & Dohme. European Study of Cohorts for Air Pollution Effects Funding: The research leading to these results has received funding from the European Community’s Seventh Framework Program ( FP7/2007-2011 ; under grant agreement no. 211250

Facilitating Learning in Large Lecture Classes: Testing the "Teaching Team" Approach to Peer Learning

We tested the effect of voluntary peer-facilitated study groups on student learning in large introductory biology lecture classes. The peer facilitators (preceptors) were trained as part of a Teaching Team (faculty, graduate assistants, and preceptors) by faculty and Learning Center staff. Each preceptor offered one weekly study group to all students in the class. All individual study groups were similar in that they applied active-learning strategies to the class material, but they differed in the actual topics or questions discussed, which were chosen by the individual study groups. Study group participation was correlated with reduced failing grades and course dropout rates in both semesters, and participants scored better on the final exam and earned higher course grades than nonparticipants. In the spring semester the higher scores were clearly due to a significant study group effect beyond ability (grade point average). In contrast, the fall study groups had a small but nonsignificant effect after accounting for student ability. We discuss the differences between the two semesters and offer suggestions on how to implement teaching teams to optimize learning outcomes, including student feedback on study groups.Integrative Biolog