COST OF FRESH MARKET CELERY PRODUCTION IN SOUTHWESTERN MICHIGAN

This bulletin represents a tool that can help producers, consultants, educators, and agribusinesses working with producers estimate costs of production and expected profit based on "typical" celery management strategies found in southwestern Michigan. The budget included in this bulletin will allow users to revise inputs based on their management strategies and calculate their expected cost and profit. This flexibility provides a decision aid to search for systems that generate higher net returns to the farm's resource base.Crop Production/Industries,

COST OF CABBAGE PRODUCTION IN MONROE COUNTY, MICHIGAN

This bulletin represents a tool that can help producers, consultants, educators, and agribusinesses working with producers estimate costs of production and expected profit based on "typical" cabbage management strategies found in Monroe County, Michigan. The budget included in this bulletin will allow users to revise inputs based on their management strategies and calculate their expected cost and profit. This flexibility provides a decision aid to search for systems that generate higher net returns to the farm's resource base.Crop Production/Industries,

Efficient multiple time scale molecular dynamics: using colored noise thermostats to stabilize resonances

Multiple time scale molecular dynamics enhances computational efficiency by updating slow motions less frequently than fast motions. However, in practice the largest outer time step possible is limited not by the physical forces but by resonances between the fast and slow modes. In this paper we show that this problem can be alleviated by using a simple colored noise thermostatting scheme which selectively targets the high frequency modes in the system. For two sample problems, flexible water and solvated alanine dipeptide, we demonstrate that this allows the use of large outer time steps while still obtaining accurate sampling and minimizing the perturbation of the dynamics. Furthermore, this approach is shown to be comparable to constraining fast motions, thus providing an alternative to molecular dynamics with constraints.Comment: accepted for publication by the Journal of Chemical Physic

Tunneling and delocalization in hydrogen bonded systems: a study in position and momentum space

Novel experimental and computational studies have uncovered the proton momentum distribution in hydrogen bonded systems. In this work, we utilize recently developed open path integral Car-Parrinello molecular dynamics methodology in order to study the momentum distribution in phases of high pressure ice. Some of these phases exhibit symmetric hydrogen bonds and quantum tunneling. We find that the symmetric hydrogen bonded phase possesses a narrowed momentum distribution as compared with a covalently bonded phase, in agreement with recent experimental findings. The signatures of tunneling that we observe are a narrowed distribution in the low-to-intermediate momentum region, with a tail that extends to match the result of the covalently bonded state. The transition to tunneling behavior shows similarity to features observed in recent experiments performed on confined water. We corroborate our ice simulations with a study of a particle in a model one-dimensional double well potential that mimics some of the effects observed in bulk simulations. The temperature dependence of the momentum distribution in the one-dimensional model allows for the differentiation between ground state and mixed state tunneling effects.Comment: 14 pages, 13 figure

Tras los pasos del mitayo: la sacralización del espacio en los corregimientos de Pacajes y Omasuyos (1570-1650)

Este trabajo propone que el traslado de los mitayos desde sus pueblos de reducción hasta las minas de Potosí se realizaba a través de caminos y espacios rituales. Según Martti Pärssinen, existió un sistema de linderos impuestos por el poder incaico en el territorio de la jefatura pakaxa, emplazada en la cuenca meridional del lago Titicaca (actual departamento de La Paz, Bolivia). A partir de esta sugerencia, reconstruimos esos «caminos de la mita», auspiciados por los líderes étnicos, que partían de los pueblos de reducción hacia espacios de congregación, para confluir en Potosí y los cerros aledaños, importantes centros de adoración surandinos. Sin negar el carácter explotativo de la mita potosina, ahondamos en otras prácticas asociadas a la misma, para recuperar algunas pautas de la religiosidad nativa, cuyas huellas son elusivas en la documentación colonial.Cet article propose que le déplacement des mitayos de leurs pueblos de reducción (villages) jusqu’aux mines de Potosí se faisait grâce à des routes et des espaces rituels. Selon Martti Pärssinen, il existait un système de limites imposées par le pouvoir inca dans le territoire de la chefferie pakaxa, situé dans le bassin méridional du lac Titicaca (actuel départament de La Paz, Bolivie). À partir de cette hypothèse, l’article reconstruit ces «chemins de la mita», contrôlés par les leaders ethniques, qui partaient des pueblos de reducción jusqu’aux espaces de rassemblement, pour confluer vers Potosí et les collines environnantes, importants centres d’adoration des Andes du sud. Sans nier le caractère exploratoire de la mita potosina, l’auteur se sert d’autres pratiques qui lui sont associées, afin de comprendre certaines tendances de la religion indigène, dont les traces sont difficiles à cerner dans les documents coloniaux.This article argues that the transfer of mitayos from their pueblos de reducción to the Potosí mines was done using ritual paths and spaces. According to Martti Pärssinen, there was a boundary system imposed by the Inkas in the core area of Pakaxa chiefdom in the southern basin of Titicaca lake (currently the Department of La Paz, Bolivia). From this suggestion, we reconstruct those “mita pathways”, overseen by ethnic leaders, which departed from the pueblos de reducción to local congregations, and ultimately converging on Potosí and the surrounding hills that were major centers of worship in the South Andes. Without denying the exploitative nature of the mita of Potosi, we dig deep into associated practices, in order to recover some patterns of native religiosity, whose traces are elusive in colonial documents