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In French parliamentary and local elections, candidates ranked first and second in the first round automatically qualify for the second round, while a third candidate qualifies only when selected by more than 12.5 percent of registered citizens. Using a fuzzy RDD around this threshold, we find that the third candidate's presence substantially increases the share of registered citizens who vote for any candidate and reduces the vote share of the top two candidates. It disproportionately harms the candidate ideologically closest to the third and causes her defeat in one fifth of the races. Additional evidence suggests that these results are driven by voters who value voting expressively over voting strategically for the top‐two candidate they dislike the least to ensure her victory; and by third candidates who, absent party‐level agreements leading to their dropping out, value the benefits associated with competing in the second round more than influencing its outcome.

U.S. states increasingly require identification to vote – an ostensive attempt to deter fraud that prompts complaints of selective disenfranchisement. Using a difference-in-differences design on a 1.6-billion-observations panel dataset, 2008–2018, we find that the laws have no negative effect on registration or turnout, overall or for any group defined by race, gender, age, or party affiliation. These results hold through a large number of specifications and cannot be attributed to voters’ reaction against the laws, measured by campaign contributions and self-reported political engagement. However, the likelihood that non-white voters were contacted by a campaign increases by 5.4 percentage points, suggesting that parties’ mobilization might have offset modest effects of the laws on the participation of ethnic minorities. Finally, strict ID requirements have no effect on fraud – actual or perceived. Overall, our findings suggest that efforts to improve elections may be better directed at other reforms.

Macrophage colony-stimulating factor (mCSF) is a cytokine known to promote the recruitment of macrophages inducing the release of CCL2, a chemokine mobilizing monocytes to sites of inflammation. Additionally, it induces microglia/macrophage proliferation and the polarization of these cells towards a M2-like phenotype, impairing their ability to release pro-inflammatory factors and toxic mediators, while favoring the release of mediators promoting tissue repair. Another important player is the mCSF receptor CSFR1, which is highly expressed in monocytes, macrophages and microglia. Here, we discuss the new interesting therapeutic avenue of the mCSF/CSFR1 axis on brain diseases. More specifically, mCSF cascade might stimulate the survival/proliferation of oligodendrocytes, enhance the immune response as well as modulate the release of growth factors and the phagocytic activity of immune cells to remove myelin debris and toxic proteins from the brain.

Background Multiple sclerosis is a neurodegenerative disorder characterized by myelin loss in the brain parenchyma. To mimic the disease, mice are fed a cuprizone-supplemented diet for 5 weeks, which leads to demyelination of white and grey matter regions, with the corpus callosum being the most susceptible to cuprizone intoxication. Although this model is highly exploited, classical behavioural tests showed inconsistent results. Objective In our study, we aimed to use the automated system Intellicage to phenotype the behaviour of cuprizone-fed mice. Methods Mice were continuously monitored during the 5 weeks of intoxication in their home cages, with minimal interference from the experimenter. Mice were assessed for spontaneous activity, fine movements, and impulsivity. Results Consistently, cuprizone-fed mice showed reduced activity and impulsivity throughout the test period. These behavioral results were confirmed by repeating the battery of behavioral tests in a second cohort of cuprizone-fed mice. Our results suggest that the behavioural phenotyping of cuprizone-fed mice using Intellicage is reproducible and sensitive enough to detect changes normally missed in standard behavioral test batteries. Conclusion Using a reproducible and standardized method to assess behavioral changes in mice intoxicated with cuprizone is crucial to better understand the disease as well as the functional outcome of treatments.

Background Improving patients’ tuberculosis (TB) knowledge is a salient component of TB control strategies. Patient knowledge of TB may encourage infection prevention behaviors and improve treatment adherence. The purpose of this study is to examine how TB knowledge and infection prevention behaviors change over the course of treatment. Methods A matched patient-health worker dataset (n = 6,031) of publicly treated TB patients with NGO-provided treatment support health workers was compiled in nine Indian cities from March 2013 to September 2014. At the beginning and end of TB treatment, patients were asked about their knowledge of TB symptoms, transmission, and treatment and infection prevention behaviors. Results Patients beginning TB treatment (n = 3,424) demonstrated moderate knowledge of TB; 52.5% (50.8%, 54.2%) knew that cough was a symptom of TB and 67.2% (65.6%, 68.7%) knew that TB was communicable. Overall patient knowledge was significantly associated with literacy, education, and income, and was higher at the end of treatment than at the beginning (3.7%, CI: 3.02%, 4.47%). Infection prevention behaviors like covering a cough (63.4%, CI: 61.2%, 65.0%) and sleeping separately (19.3%, CI: 18.0%, 20.7%) were less prevalent. The age difference between patient and health worker as well as a shared language significantly predicted patient knowledge and adherence to infection prevention behaviors. Conclusions Social proximity between health worker and patients predicted greater knowledge and adherence to infection prevention behaviors but the latter rate remains undesirably low.

We study the demand for household water connections in urban Morocco, and the effect of such connections on household welfare. In the northern city of Tangiers, among homeowners without a private connection to the city's water grid, a random subset was offered a simplified procedure to purchase a household connection on credit (at a zero percent interest rate). Take-up was high, at 69%. Because all households in our sample had access to the water grid through free public taps (often located fairly close to their homes), household connections did not lead to any improvement in the quality of the water households consumed; and despite significant increase in the quantity of water consumed, we find no change in the incidence of waterborne illnesses. Nevertheless, we find that households are willing to pay a substantial amount of money to have a private tap at home. Being connected generates important time gains, which are used for leisure and social activities, rather than productive activities. Because water is often a source of tension between households, household connections improve social integration and reduce conflict. Overall, within 6 months, self-reported well-being improved substantially among households in the treatment group, despite the financial cost of the connection. Our results suggest that facilitating access to credit for households to finance lump sum quality-of-life investments can significantly increase welfare, even if those investments do not result in income or health gains.

The authors present suggestions by graduate students from a range of economics departments for improving the first-year core sequence in economics. The students identified a number of elements that should be added to the core: more training in building microeconomic models, a discussion of the methodological foundations of model-building, more emphasis on institutions to motivate and contextualize macroeconomic models, and greater focus on econometric practice rather than theory. The authors hope that these suggestions will encourage departments to take a fresh look at the content of the first-year core.

Reaction of NaBH4 with (tBuPOCOP)IrHCl affords the previously reported complex (tBuPOCOP)IrH2(BH3) (1) (tBuPOCOP = kappa(3)-C6H3-1,3-[OP(tBu)2]2). The structure of 1 determined from neutron diffraction data contains a B-H sigma-bond to iridium with an elongated B-H bond distance of 1.45(5) A. Compound 1 crystallizes in the space group P1 (Z = 2) with a = 8.262 (5) A, b = 12.264 (5) A, c = 13.394 (4) A, and V = 1256.2 (1) A(3) (30 K). Complex 1 can also be prepared by reaction of BH3 x THF with (tBuPOCOP)IrH2. Reaction of (tBuPOCOP)IrH2 with pinacol borane gave initially complex 2, which is assigned a structure analogous to that of 1 based on spectroscopic measurements. Complex 2 evolves H2 at room temperature leading to the borane complex 3, which is formed cleanly when 2 is subjected to dynamic vacuum. The structure of 3 has been determined by X-ray diffraction and consists of the (tBuPOCOP)Ir core with a sigma-bound pinacol borane ligand in an approximately square planar complex. Compound 3 crystallizes in the space group C2/c (Z = 4) with a = 41.2238 (2) A, b = 11.1233 (2) A, c = 14.6122 (3) A, and V = 6700.21 (19) A(3) (130 K). Reaction of (tBuPOCOP)IrH2 with 9-borobicyclononane (9-BBN) affords complex 4. Complex 4 displays (1)H NMR resonances analogous to 1 and exists in equilibrium with (tBuPOCOP)IrH2 in THF solutions.

The complex OsCl(NH=C(Ph)C 6 H 4 )(PiPr 3 ) 2 (H 2 ) (1) has been characterized by Esteruelas and coworkers (Organometallics 1998, 17, 4065-4076) as an elongated dihydrogen complex based on relaxation time measurements and observation of J H-D = 6.3 Hz in 1-d 1 . Variable-temperature NMR studies were reported in which the single hydride resonance observed at ambient temperature decoalesced into two signals at low temperature (193 K), which was attributed to hindered rotation of the bound H 2 ligand. Reinvestigation of the low-temperature NMR spectra of 1 reveals a more complex situation. Examination of the 1 H and 31 P NMR spectra of 1 and 1-d 1 at lower temperatures than previously studied demonstrates that quantum mechanical exchange coupling is observed between the metal-bonded hydrogen atoms. This coupling is quenched in 1-d 1 . Hindered rotation around Os-P bonds in 1 also contributes to the observed NMR spectra.

Reaction of [Cp*Ir(CH3CN)3][PF6]2 with methylenebis(N-methylimidazolium) iodide in the presence of Et3N affords [Cp*Ir(C−C)I]PF6 (1) (C−C = bis-carbene). The structure of complex 1 was confirmed by X-ray crystallography. The chloride analogue [Cp*Ir(C−C)Cl]X (2) was similarly prepared from [Cp*Ir(CH3CN)3][PF6]2 (X = PF6) or [Cp*IrCl2]2 (X = Cl) and methylenebis(N-methylimidazolium) chloride. Reaction of 2 (X = Cl) with Et3SiB(C6F5)4 under hydrogen gas gives the dicationic dihydrogen complex [Cp*Ir(C−C)(H2)]2+ (3). Complex 3 is identified as a dihydrogen complex based on T1(min) = 37 ms for the hydride resonance (240 K, 750 MHz) and JHD = 23.5 Hz in the partially deuterated analogue.

Reaction of [Cp*Ir(P-P)Cl][B(C6F5)4] (P-P = bisdimethydiphosphinomethane (dmpm), bisdiphenyldiphosphinomethane (dppm)) with [Et3Si][B(C6F5)4] in methylene chloride under 1 atm of hydrogen gas affords the dicationic compressed dihydride complexes [Cp*Ir(P-P)H2][B(C6F5)4]2. These dicationic complexes are highly acidic and are very readily deprotonated to the corresponding monohydride cations. When the preparative reaction is carried out under HD gas, the hydride resonance exhibits JHD = 7-9 Hz, depending upon the temperature of observation, with higher values of JHD observed at higher temperatures. A thermally labile rhodium analogue, [CpRh(dmpm)(H2)][B(C6F5)4]2, was prepared similarly. A sample prepared with HD gas gave JHD = 31 Hz and J(HRh) = 31 Hz, allowing the Rh complex to be identified as a dihydrogen complex. Quantum dynamics calculations on a density functional theory (DFT) potential energy surface have been used to explore the structure of the Ir complexes, with particular emphasis on the nature of the potential energy surface governing the interaction between the two hydride ligands and the Ir center.

Irradiation of [TpMe2,ClRh(CO)2] [TpMe2,Cl = hydridotris(4-chloro-3,5-dimethylpyrazolyl)borate] in diisopropylamine yields the C–H activated metallacycle [TpMe2,ClRhH{CH2CH(CH3)NHiPr}] as a single diastereomer.

Ammonia–borane, H3NBH3, is an intriguing molecule for chemical hydrogen storage applications. With both protic N–H and hydridic B–H bonds, three H atoms per main group element, and a low molecular weight, H3NBH3 has the potential to meet the stringent gravimetric and volumetric hydrogen storage capacity targets needed for transportation applications. Furthermore, devising an energy-efficient chemical process to regenerate H3NBH3 from dehydrogenated BNHx material is an important step towards realization of a sustainable transportation fuel. In this perspective we discuss current progress in catalysis research to control the rate and extent of hydrogen release and preliminary efforts at regeneration of H3NBH3.

In the presence of an iridium pincer complex, dehydrogenation of ammonia borane (H3NBH3) occurs rapidly at room temperature in tetrahydrofuran to generate 1.0 equivalent of H2 and [NH2BH2]5. A metal borohydride complex has been isolated as a dormant form of the catalyst which can be reactivated by reaction with H2.

Photolysis of solutions of M(CO)6 (M = Cr, Mo, and W) in the presence of Et3SiH affords the silane complexes Cr(CO)5(eta2-HSiEt3), Mo(CO)5(eta2-HSiEt3), and W(CO)5(eta2-HSiEt3). Observed values of J(SiH) in these complexes are consistent with modest elongation of the Si-H bond. With Ph3SiH, complexes of Cr(CO)5 and W(CO)5 were obtained, but no complex with Mo was observed. When Ph2SiH2 was employed, only one Si-H bond interacts with the metal center. A dynamic exchange process observable on the magnetic resonance time scale exchanges the pendant and coordinated Si-H bonds of the coordinated diphenylsilane. Silanes bound to M(CO)5 are activated with respect to reaction with nucleophiles. With methanol, catalytic methanolysis of HSiEt3 has been observed in the presence of Cr(CO)5(eta2-HSiEt3), affording Et3SiOMe.

Photolysis of dichloromethane solutions of M(CO)6 (M = Cr, W) at low temperature in the presence of hydrogen gas affords W(CO)5(H2) (1) and Cr(CO)5(H2) (2). Complexes 1 and 2 are characterized as dihydrogen complexes based on short T1 values for the hydride resonances and a large HD coupling of 35.3 Hz (W) and 35.8 Hz (Cr) in the HD derivatives. A cationic analogue, [Re(CO)5(H2)]+ (3), was prepared by reaction of Re(CO)5Cl with [Et3Si][B(C6F5)4] in fluorobenzene under hydrogen. Complex 3-d1 exhibits JHD = 33.9 Hz. Complex 3 is strongly acidic, with complete deprotonation by diethyl ether; complexes 1 and 2 are moderately acidic. Deprotonation of 1 is complete in the presence of one equivalent of triethylamine.

In contrast to [Cp(2)MoH(3)](+), which is a thermally stable trihydride complex, the ansa-bridged analogue [(eta-C(5)H(4))(2)CMe(2)MoH(H(2))](+) (1) is a thermally labile dihydrogen/hydride complex. Partial deuteration of the hydride ligands allows observation of J(H)(-)(D) = 11.9 Hz in 1-d(1) and 9.9 Hz in 1-d(2) (245 K), indicative of a dihydrogen/hydride structure. There is a slight preference for deuterium to concentrate in the dihydrogen ligand. A rapid dynamic process interchanges the hydride and dihydrogen moieties in complex 1. Low temperature (1)H NMR spectra of 1 give a single hydride resonance, which broadens at very low temperature due to rapid dipole-dipole relaxation (T(1) = 23 ms (750 MHz, 175 K) for the hydride resonance in 1). Low temperature (1)H NMR spectra of 1-d(2) allow the observation of decoalescence at 180 K into two resonances. The bound dihydrogen ligand exhibits hindered rotation with DeltaG(150) = 7.4 kcal/mol, but H atom exchange is still rapid at all accessible temperatures (down to 130 K). Density functional calculations confirm the dihydrogen/hydride structure as the ground state for the molecule and give estimates for the energy of two hydrogen exchange processes in good agreement with experiment. The presence of the C ansa bridge is shown to decrease the ability of the metallocene fragment to donate to the hydrogens, thus stabilizing the (eta(2)-H(2)) unit and modulating the barrier to H(2) rotation.

Reaction of [Cp*Ir(dmpm)Cl]Cl with [Et3Si]B(ArF)4 (dmpm = bisdimethyl-phosphinomethane; ArF = C6F5) under hydrogen gas affords the dicationic complex [Cp*Ir(dmpm)H2]2+ (1), which is readily deprotonated by weak bases to give [Cp*Ir(dmpm)H]+. Complex 1 exists as a mixture of two isomers (97:3). On the basis of the magnitude of 2JH-P couplings and T1 measurements, a cis-dihydride or dihydrogen complex structure is suggested for the predominant isomer 1-cis (2JH-P = 6 Hz), with the minor isomer assigned a transoid structure 1-trans (2JH-P = 20 Hz). When the preparative reaction is carried out with HD gas, the resonance in the 1H NMR spectrum assigned to 1-cis-d1 exhibits1JH-D = 9.0 Hz. The observed values of 1JH-D vary significantly with temperature, increasing from 7.0 Hz at 223K to 9.0 Hz at 300 K. The observed chemical shift of 1-cis-d1 also varies significantly with temperature. These observations are interpreted in terms of a dynamic equilibrium between a cis-dihydride and a dihydrogen complex.

Lors des dernieres elections regionales, une enquete menee en Ile-de-France sur les formes de mobilisation politique a montre le potentiel inexploite de mobilisation d’une part significative de l’electorat. Un changement du mode de campagne, privilegiant le porte-a-porte, donne un resultat significatif sur la participation, en particulier pour les minorites les plus eloignees du vote. Une nouvelle approche des raisons de l’abstention ?

In situ(11)B NMR monitoring, computational modeling, and external trapping studies show that selectivity and extent of H(2) release in metal-catalysed dehydrogenation of ammonia borane, NH(3)BH(3), are determined by coordination of reactive aminoborane, NH(2)BH(2), to the metal center.