Reactions forming C(0,+)n=2,10, Cn=2,4H(0,+) and C3H(0,+) in the gas phase: semi empirical branching ratios

The aim of this paper is to provide a new set of branching ratios for interstellar and planetary chemical networks based on a semi empirical model. We applied, instead of zero order theory (i.e. only the most exoergic decaying channel is considered), a statistical microcanonical model based on the construction of breakdown curves and using experimental high velocity collision branching ratios for their parametriza- tion. We applied the model to ion-molecule, neutral-neutral, and ion-pair reactions implemented in the few popular databases for astrochemistry such as KIDA, OSU and UMIST. We studied the reactions of carbon and hydrocarbon species with electrons, He+, H+, CH+, CH, C, and C+ leading to intermediate complexes of the type Cn=2,10, Cn=2,4 H, C3 H2, C+n=2,10, Cn=2,4 H+, or C3 H+2 . Comparison of predictions with measurements supports the validity of the model. Huge deviations with respect to database values are often obtained. Effects of the new branching ratios in time dependant chemistry for dark clouds and for photodissociation region chemistry with conditions similar to those found in the Horsehead Nebula are discussed

Integrating service-learning into dietetics and nutrition education

This article presents a review of the service-learning literature as a foundation for a discussion on integrating service-learning into dietetics and nutrition education. The purposes of this review are to (1) define service-learning, (2) discuss how service-learning can enhance dietetics and nutrition education programs, (3) explain principles and best practices fur integrating service-learning into dietetics and nutrition curricula, and ( 4) outline practical tips for orienting students for this experience and establishing sites for service-learning activities. The information shared has pedagogical implications and is transferable to any dietetics and nutrition education program

Performance, Ritual, and Procession: The Metropolitan Museum of Art’s Our Lady of Cocharcas

Statue paintings created in the colonial Andes are extraordinary artworks infused with elements that represent local beliefs and rituals. This study investigates this tradition through The Met’s Our Lady of Cocharcas to reveal the stunning complexity of religious visual art produced during the late colonial period

The CountEm software: simple, efficient and unbiased population size estimation

Population size estimation is essential in ecology and conservation studies. Aerial photography can facilitate this laborious task with high resolution images. However, in images with thousands of individuals exhaustive manual counting is tedious, slow and difficult to verify. Computer vision software may work under some particular conditions but they are generally biased and known to fail in several situations. The CountEm software is a simple alternative based on geometric sampling. It provides a fast and unbiased size estimation for all sorts of populations. The only requirement is that the discrete objects (e.g. animals) in the target population are unambiguously distinguishable for counting in a still image. Typical relative standard errors in the 5?10% range are obtained after counting ~200 properly sampled animals in about 5?min irrespective of population size. The CountEm ver. 1.4.1 is presented here, which includes a guided mode with a simple software interface.MC acknowledges financial support from the AYA-2015-66357-R (MINECO/FEDER) project

Charge-Transfer Excitations in the Model Superconductor HgBa2_2CuO4+δ_{\bf 4+\delta}

We report a Cu $K$-edge resonant inelastic x-ray scattering (RIXS) study of charge-transfer excitations in the 2-8 eV range in the structurally simple compound HgBa$_2$CuO$_{4+\delta}$ at optimal doping ($T_{\rm c} = 96.5$ K). The spectra exhibit a significant dependence on the incident photon energy which we carefully utilize to resolve a multiplet of weakly-dispersive ($< 0.5$ eV) electron-hole excitations, including a mode at 2 eV. The observation of this 2 eV excitation suggests the existence of a charge-transfer pseudogap deep in the superconducting phase. Quite generally, our data demonstrate the importance of exploring the incident photon energy dependence of the RIXS cross section.Comment: 5 pages, 3 figure