C–N bond formation between alcohols and amines using an iron cyclopentadienone catalyst

An iron-tetraphenylcyclopentadienone tricarbonyl complex is demonstrated to act as a precursor of a catalyst for the formation of C–N bonds through a “hydrogen-borrowing” reaction between amines and alcohols

Crime and Deterrence: Correlation Analysis

A correlation analysis of the severity and certainty of punish ment and offense rates for the major index crimes produces results consistent with the predictions of deterrence theory. Certainty of punishment proves to be the chief deterrent for most crimes. Homicide, however, is influenced by severity, pos sibly reflecting the differences between homicide and other of fenses. Little evidence of interaction is found between certainty and severity in effects on crime rate. A powerfunction proves to better describe the relationship between the punishment varia bles and crime rates than a rectilinear equation-a conclusion which, even apart from the date, appears more reasonable than the reverse

Taste activity in the parabrachial region in adult rats following neonatal chorda tympani transection

The chorda tympani is a gustatory nerve that fails to regenerate if sectioned in rats 10 days of age or younger. This early denervation causes an abnormally high preference for NH4Cl in adult rats, but the impact of neonatal chorda tympani transection on the development of the gustatory hindbrain is unclear. Here, we tested the effect of neonatal chorda tympani transection (CTX) on gustatory responses in the parabrachial nucleus (PbN). We recorded in vivo extracellular spikes in single PbN units of urethane-anesthetized adult rats following CTX at P5 (chronic CTX group) or immediately prior to recording (acute CTX group). Thus, all sampled PbN neurons received indirect input from taste nerves other than the CT. Compared to acute CTX rats, chronic CTX animals had significantly higher responses to stimulation with 0.1 and 0.5 M NH4Cl, 0.1 NaCl, and 0.01 M citric acid. Activity to 0.5 M sucrose and 0.01 M quinine stimulation was not significantly different between groups. Neurons from chronic CTX animals also had larger interstimulus correlations and significantly higher entropy, suggesting that neurons in this group were more likely to be activated by stimulation with multiple tastants. Although neural responses were higher in the PbN of chronic CTX rats compared to acute-sectioned controls, taste-evoked activity was much lower than observed in previous reports, suggesting permanent deficits in taste signaling. These findings demonstrate that the developing gustatory hindbrain exhibits high functional plasticity following early nerve injury

Environmental enteric dysfunction and the fecal microbiota in malawian children

Environmental enteric dysfunction (EED) is often measured with a dual sugar absorption test and implicated as a causative factor in childhood stunting. Disturbances in the gut microbiota are hypothesized to be a mechanism by which EED is exacerbated, although this supposition lacks support. We performed 16S ribosomal RNA gene sequencing of fecal samples from 81 rural Malawian children with varying degrees of EED to determine which bacterial taxa were associated with EED. At the phyla level, Proteobacteria abundance is reduced with severe EED. Among bacterial genera, Megasphaera, Mitsuokella, and Sutterella were higher in EED and Succinivibrio, Klebsiella, and Clostridium_XI were lower in EED. Bacterial diversity did not vary with the extent of EED. Though EED is a condition that is typically believed to affect the proximal small bowel, and our focus was on stool, our data do suggest that there are intraluminal microbial differences that reflect, or plausibly lead to, EED

Comparison between integral equation method and molecular dynamics simulation for three-body forces: Application to supercritical argon

The prediction of the structural and thermodynamic properties of supercritical argon has been carried out by two independent routes: semianalytical calculations and numerical simulations. The first one is based on the hybridized mean spherical approximation (HMSA) conjugated with an effective pair potential that incorporates multipole dispersion interactions. The second one uses a very recent numerical simulation technique, inspired by the Car–Parrinello method [van der Hoef et al., J. Chem. Phys. 111, 1520 (1999)], which contains an effective quantum-mechanical representation of the underlying electronic structure. The latter approach allows us to treat the contribution of the three-body effects as well, and to validate the use of an effective pair potential for them in the framework of the self-consistent integral equation method. For all the supercritical argon states studied, the results obtained with the semianalytical approach are in good agreement with the predictions of the numerical simulation. Here it is shown that HMSA remains competitive with molecular dynamics simulation when the triple-dipole and the dipole–dipole–quadrupole three-body terms are taken into accoun

A novel class of CoA-transferase involved in short-chain fatty acid metabolism in butyrate-producing human colonic bacteria

Peer reviewedPublisher PD