Automatic Generation of Matrix Element Derivatives for Tight Binding Models

Tight binding (TB) models are one approach to the quantum mechanical many particle problem. An important role in TB models is played by hopping and overlap matrix elements between the orbitals on two atoms, which of course depend on the relative positions of the atoms involved. This dependence can be expressed with the help of Slater-Koster parameters, which are usually taken from tables. Recently, a way to generate these tables automatically was published. If TB approaches are applied to simulations of the dynamics of a system, also derivatives of matrix elements can appear. In this work we give general expressions for first and second derivatives of such matrix elements. Implemented in a computer program they obviate the need to type all the required derivatives of all occuring matrix elements by hand.Comment: 11 pages, 2 figure

Conversion of hydroxyproline to pyrrole-2-carboxylic acid

This article does not have an abstract

Understanding values associated with stormwater remediation options in marine coastal ecosystems: A case study from Auckland, New Zealand

This paper describes the design and implementation of a choice experiment to understand Aucklanders’ preferences for environmental qualities associated with the effects of urban run-off on marine coastal environments. Auckland’s coastal environments are affected by a range of ecological and human factors. While much research has been undertaken in the area of ecology, little is understood of human preferences for coastal environments and their management. An unlabelled choice experiment was developed with three environmental quality attributes specified at three broad coastal categories. The environmental qualities are ecological health, water clarity, and underfoot conditions. Willingness to pay estimates for these attributes indicates that respondents show a strong preference for improved environmental quality at outer coastal beach locations over middle and upper harbour locations. Water quality leads ecological health, then underfoot conditions in importance at beach locations. An application is discussed in which a hypothetical project consisting of policy and engineering components delivers changes in water quality and underfoot conditions in the Auckland upper harbour areas. A 95% confidence estimate of the money value of that change ranges from $783 m. to$ 1,122 b. The key outcome is demonstration of the choice experiment as a statistically robust and flexible approach to making sense of Aucklanders’ complex preferences for coastal ecosystem management.Environmental Economics and Policy, Research Methods/ Statistical Methods,

Enzymatic synthesis of L-pipecolic acid and L-proline

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Intercellular ultrafast Ca(2+) wave in vascular smooth muscle cells: numerical and experimental study.

Vascular smooth muscle cells exhibit intercellular Ca(2+) waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca(2+) wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca(2+) wave and it was suggested to be the result of the interplay between membrane potential and Ca(2+) dynamics which depended on influx of extracellular Ca(2+), cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca(2+) wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca(2+) wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca(2+) wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca(2+) waves in smooth muscle cells

Hidden in White(ness)? Using Racial Logics to Interrogate the Instructional Arc of a Crisis Intervention Team Training

Some scholars argue that communities of color have been historically considered criminal by law enforcement (Fanon, 1963/2004; Gordon, 1996; Sharpley-Whiting, 1999), and Parenti (2003) and Kendi (2016) traced the history of modern policing to slave patrols. Wynter (2003) illuminated the racial logics undergirding our society - including policing - to the overlay of monotheism and its fixity with racial constructions of human as historically rooted in slavery and colonization. Thus, policing, too, carries a racialized dimension (Gamal, 2016) that creates or amplifies trauma and mental illness (Westcott, 2015). To address mental health, an undergirding feature of use of force and racialized policing, many cities have adopted Crisis Intervention Team (CIT) training for police personnel, a 40-hour training in partnership with health community resources and mental health experts (Watson, Morabito, Draine, & Ottati, 2008) intended to promote de-escalation and communication between police and communities. For this Educational Criticism (Eisner, 1998), I first utilized interviews to consider how the officers leading the training think about CIT\u27s purposes and content. I then observed the training to examine the relationship between trainer\u27s intentions and what occurs. Last, I explored what the police officers learned, connecting to how individual police officers make sense of the training to consider to what extent the training evinces or contests the racial logics of violence and whiteness tied into constructions of human. I found CIT training to use colorblind and universal language to describe communication between police and various populations while also coding racialized perception of neighborhoods and criminals. This coding relates to officers\u27 perception of danger and, thus, whether they utilize CIT strategies or other tactics in working with populations. Therefore, racial coding without explicit address in the training contributes to a lack of awareness and reflection of the role of race in interactions, potentially impacting discretion and use of force. Address of the role of institutional and individual racism as it relates to CIT ought to be incorporated in trainings to enhance officer efficacy

High-Fidelity Digital Twins: Detecting and Localizing Weaknesses in Structures

An adjoint-based procedure to determine weaknesses, or, more generally, the material properties of structures is developed and tested. Given a series of load cases and corresponding displacement/strain measurements, the material properties are obtained by minimizing the weighted differences between the measured and computed values. In a subsequent step, techniques to minimize the number of load cases and sensors are proposed and tested. Several examples show the viability, accuracy and efficiency of the proposed methodology and its potential use for high fidelity digital twins.Comment: arXiv admin note: substantial text overlap with arXiv:2303.1532

Radiative corrections to all charge assignments of heavy quark baryon semileptonic decays

In semileptonic decays of spin-1/2 baryons containing heavy quarks up to six charge assignments for the baryons and lepton are possible. We show that the radiative corrections to four of these possibilities can be directly obtained from the final results of the two possibilities previously studied. There is no need to recalculate integrals over virtual or real photon momentum or any traces.Comment: 15 pages, 2 figures, RevTex. Extended discussion. Final version to appear in Physical Review