The switching point between kinetic and thermodynamic control

In organic chemistry, the switching point between the kinetic and thermodynamic control regimes of two competitive, parallel reactions is widely studied. A new definition for this switching point is proposed: the time at which the rates of formation of the competing products are equal. According to this definition, the kinetic control regime is present from the beginning of the reaction, and is valid as long as the rate of formation of the kinetic product is larger than the rate of formation of the thermodynamic product. On the switching point, both rates of formation are equal, so, from this switching point the thermodynamic product has a larger rate of formation, and the thermodynamic control remains until the end of the reaction. A closed form expression is given for the proposed time of the switching point, as a function of the direct and inverse kinetic constants of both competing reactions, as well as the initial concentrations of the starting reagent and the competing products. The concept of competing control regimes is extended also to the case where the reactions start from two competitive reagents which decompose to produce a single product. (C) 2016 Elsevier Ltd. All rights reserved

Software for Exact Integration of Polynomials over Polyhedra

We are interested in the fast computation of the exact value of integrals of polynomial functions over convex polyhedra. We present speed ups and extensions of the algorithms presented in previous work. We present the new software implementation and provide benchmark computations. The computation of integrals of polynomials over polyhedral regions has many applications; here we demonstrate our algorithmic tools solving a challenge from combinatorial voting theory.Comment: Major updat

The Cost Of CMM Deployment In A Conventional IT Organization: A Field Study

Over the past decade the software industry has periodically tried to upgrade its business perform-ance by deploying strategic infrastructure frameworks based on expert models. Each of these schemes is aimed at organizing software work along the lines of commonly understood best prac-tice. Their goal is to optimally align the policies and practices of the IT function so that they di-rectly support and further the purposes and goals of the overall business operation (Lewis, 2001). Although there are no authoritative statistics, arguably one of the most popular approaches is the Software Engineering Institute’s (SEI) Capability Maturity Model (CMM v1.1) moreover it is certainly the framework of choice for the U.S. software industry. It was developed out of the research of Watts Humphrey and the Mitre Corporation and was first published by SEI in 1987 (Humphrey, 87a). Operationally, it is designed to advance the software organization’s processes through five stages, or levels, of increasingly effective performance ranging from Chaos (At the initial end) to Optimized (at the high end). The organization adds best practices at each level, which both underwrites improved performance at that particular stage, as well as leverages advancement to the next stage. The problem is that the “best practices” deployed by CMM are both generic and externally (from the company’s perspective) defined. Consequently they require a complicated and expensive implementation process to specifically tailor the model for each organizational situation.  Since the costs of this are concrete and in the near term and the benefits are (to some extent) intangible and long run, the practical question posed by most CEOs is… “Exactly how much will this cost me?” The lack of a definitive answer to that question has been a barrier to adoption, as well as a source of genuine concern among most business executives. So, there have been numerous studies aimed at determining precisely what the costs and benefits of CMM implementation are. These have been conducted primarily in large, or leading edge organizations (these are best summarized in McGibbon, 1999). However, because such businesses are materially different both in their products and their processes, they tend to start from a different point and they have different requirements than the average small IT shop. So the question remains, “what are the factors and exactly how involved and costly is it to implement CMM in a conventional IT setting?”  That is what we are attempting to answer with this research

Possible Stellar Metallicity Enhancements from the Accretion of Planets

A number of recently discovered extrasolar planet candidates have surprisingly small orbits, which may indicate that considerable orbital migration takes place in protoplanetary systems. A natural consequence of orbital migration is for a series of planets to be accreted, destroyed, and then thoroughly mixed into the convective envelope of the central star. We study the ramifications of planet accretion for the final main sequence metallicity of the star. If maximum disk lifetimes are on the order of 10 Myr, stars with masses near 1 solar mass are predicted to have virtually no metallicity enhancement. On the other hand, early F and late A type stars with masses of 1.5--2.0 solar masses can experience significant metallicity enhancements due to their considerably smaller convection zones during the first 10 Myr of pre-main-sequence evolution. We show that the metallicities of an aggregate of unevolved F stars are consistent with an average star accreting about 2 Jupiter-mass planets from a protoplanetary disk having a 10 Myr dispersal time.Comment: 14 pages, AAS LaTeX, 3 figures, accepted to ApJ Letter

New invariant expressions in chemical kinetics

This paper presents a review of our original results obtained during the last decade. These results have been found theoretically for classical mass-action-law models of chemical kinetics and justified experimentally. In contrast with the traditional invariances, they relate to a special battery of kinetic experiments, not a single experiment. Two types of invariances are distinguished and described in detail: thermodynamic invariants, i.e., special combinations of kinetic dependences that yield the equilibrium constants, or simple functions of the equilibrium constants; and "mixed" kinetico-thermodynamic invariances, functions both of equilibrium constants and non-thermodynamic ratios of kinetic coefficients

Alternative methods of determining hamstrings-to-quadriceps ratios: A comprehensive review

The hamstrings-to-quadriceps muscle strength ratio calculated by peak torque has been used as an important tool to detect muscle imbalance, monitor knee joint stability, describe muscle strength properties and functionality, and for lower extremity injury prevention and rehabilitation. However, this ratio does not consider other neuromuscular variables that can also influence the antagonist to agonist muscle relationship, such as torque produced at multiple angles of range of motion, explosive strength, muscle size, muscle fatigue, or muscle activation. The aim of this study was to comprehensively review alternative methods of determining the hamstrings-to-quadriceps ratio. These include ratios calculated by angle-specific torque, rate of torque development, muscle size, fatigue index, and muscle activation (measured by electromyography). Collectively, the literature demonstrates that utilizing alternative methods of determining the hamstrings-to-quadriceps ratio can be functionally relevant for a better understanding of the neuromuscular mechanisms underpinning the interaction of strength between hamstrings and quadriceps. However, there is insufficient evidence to recommend any of the alternative methods as sensitive clinical tools for predicting injury risk and monitoring knee joint integrity. Future longitudinal studies, along with injury incidence, are needed to further investigate all alternative methods of determining the hamstrings-to-quadriceps ratio. These have potential to offer insight into how athletes and the general population should be trained for performance enhancement and injury reduction, and may be used along with traditional methods for a thorough assessment of an individual\u27s H:Q muscle balance

Macroclimate and viticultural zoning in Europe: observed trends and atmospheric forcing

Temperature and precipitation are major forcing factors influencing grapevine phenology and yield, as well as wine quality. Bioclimatic indices describing the suitability of a particular region for wine production are a commonly used tool for viticultural zoning. For this research these indices were computed for Europe by using the E-OBS gridded daily temperature and precipitation data set for the period from 1950 to 2009. Results showed strong regional contrasts based on the different index patterns and reproduced the wide diversity of local conditions that largely explain the quality and diversity of grapevines being grown across Europe. Owing to the strong inter-annual variability in the indices, a trend analysis and a principal component analysis were applied together with an assessment of their mean patterns. Significant trends were identified in the Winkler and Huglin indices, particularly for southwestern Europe. Four statistically significant orthogonal modes of variability were isolated for the Huglin index (HI), jointly representing 82% of the total variance in Europe. The leading mode was largely dominant (48% of variance) and mainly reflected the observed historical long-term changes. The other 3 modes corresponded to regional dipoles within Europe. Despite the relevance of local and regional climatic characteristics to grapevines, it was demonstrated via canonical correlation analysis that the observed inter-annual variability of the HI was strongly controlled by the large-scale atmospheric circulation during the growing season (April to September)

Mitogenome analyses reveal limited introduction of Anopheles coluzzii into the central African islands of São Tomé and Príncipe.

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Diverse manganese(II)‐oxidizing bacteria are prevalent in drinking water systems

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136363/1/emi412508_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136363/2/emi412508.pd

Complete mitogenome sequence of Anopheles coustani from São Tomé island

We report the first complete mitogenome (Mt) sequence of Anopheles coustani, an understudied malaria vector in Africa. The sequence was extracted from one individual mosquito from São Tomé island. The length of the A. coustani Mt genome was 15,408 bp with 79.3% AT content. Phylogenetic analysis revealed that A. coustani is most closely related to A. sinensis (93.5% of identity); and 90.1% identical to A. gambiae complex members.publishersversionpublishe