Interplay of point multipole moments and charge penetration for intermolecular electrostatic interaction energies from the University at Buffalo pseudoatom databank model of electron density

2017 ◽  
Vol 73 (4) ◽  
pp. 598-609 ◽  
Author(s):  
Sławomir A. Bojarowski ◽  
Prashant Kumar ◽  
Paulina M. Dominiak
Keyword(s):  
Electrostatic Interaction ◽  
The Other ◽  
Continuous Representation ◽  
Interaction Energies ◽  
Multipole Moments ◽  
Equilibrium Distance ◽  
Energy Estimation ◽  
The University ◽  
Nonpolar Molecules

The strength of the University at Buffalo DataBank (UBDB) inEesestimation is mainly due to charge overlap effects because the UBDB offers continuous representation of charge density which allows for a direct account of charge penetration in the derivation of electrostatic energies. In the UBDB model, these effects begin to play an important role at distances below twice the equilibrium distance and significantly increase as distances decrease. At equilibrium distances they are responsible for 30–50% ofEesfor polar molecules and around 90% ofEesfor nonpolar molecules. When the energy estimation from the UBDB is reduced to point multipoles, the results are comparable to point charges fitted to electrostatic potentials. On the other hand, particular components of energy from point multipole moments from the UBDB model are sensitive to the type of interaction and might be helpful in the characterization of interactions.

Fast analytical evaluation of intermolecular electrostatic interaction energies using the pseudoatom representation of the electron density. I. The Löwdin α-function method

2018 ◽  
Vol 74 (5) ◽  
pp. 524-536 ◽  
Author(s):  
Daniel Nguyen ◽  
Zbigniew Kisiel ◽  
Anatoliy Volkov
Keyword(s):  
Electrostatic Interaction ◽  
Multipole Moment ◽  
Chem Phys ◽  
Processing Unit ◽  
Interaction Energies ◽  
Electron Densities ◽  
Molecular Systems ◽  
Analytical Technique ◽  
Central Processing ◽  
The University

The previously reported [Volkovet al.(2004).Chem. Phys. Lett.391, 170–175] exact potential and multipole moment (EP/MM) method for evaluation of intermolecular electrostatic interaction energies using the nuclei-centered pseudoatom representation of electron densities is significantly improved in terms of both speed and accuracy by replacing the numerical quadrature integration of the exact potential with a fully analytical technique. The resulting approach, incorporated in theXDPROPmodule of the software packageXD, has been tested on several molecular systems ranging in size from water–water to dodecapeptide–dodecapeptide dimers using electron densities constructedviathe University at Buffalo Aspherical Atom Databank. The improved hybrid method provides electrostatic interaction energies within the uncertainty of ≤0.2 kJ mol−1for all benchmark systems. The running time for a dimer of a sizable, 225-atom dodecapeptide is under 4 s on a 2012 central processing unit (2.8 GHz AMD Opteron 6348) and under 3 s on a relatively modern processor (2.8 GHz Intel Xeon E3-1505M v5).

A very rapid in situ Kikuchi technique to determine relative crystal misorientation

1988 ◽  
Vol 46 ◽  
pp. 830-831
Author(s):  
J. I. Bennetch
Keyword(s):  
Electron Beam ◽  
Analytical Techniques ◽  
Superplastic Forming ◽  
The Other ◽  
Kikuchi Pattern ◽  
Kikuchi Line ◽  
Line Analysis

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.

Determination of the lattice translation across {110} APBs in GaAs

1988 ◽  
Vol 46 ◽  
pp. 600-601
Author(s):  
D.R. Rasmussen ◽  
N.-H. Cho ◽  
C.B. Carter
Keyword(s):  
Grain Boundaries ◽  
Lower Energy ◽  
Antiphase Boundary ◽  
The Other ◽  
Boundary Structure ◽  
Interface Plane ◽  
Inversion Symmetry ◽  
High Angle ◽  
Equilibrium Distance

Domains in GaAs can exist which are related to one another by the inversion symmetry, i.e., the sites of gallium and arsenic in one domain are interchanged in the other domain. The boundary between these two different domains is known as an antiphase boundary [1], In the terminology used to describe grain boundaries, the grains on either side of this boundary can be regarded as being Σ=1-related. For the {110} interface plane, in particular, there are equal numbers of GaGa and As-As anti-site bonds across the interface. The equilibrium distance between two atoms of the same kind crossing the boundary is expected to be different from the length of normal GaAs bonds in the bulk. Therefore, the relative position of each grain on either side of an APB may be translated such that the boundary can have a lower energy situation. This translation does not affect the perfect Σ=1 coincidence site relationship. Such a lattice translation is expected for all high-angle grain boundaries as a way of relaxation of the boundary structure.

Rapid Isolation of High Molecular Weight Urokinase from Native Human Urine

1982 ◽  
Vol 47 (03) ◽  
pp. 197-202 ◽  
Author(s):  
Kurt Huber ◽  
Johannes Kirchheimer ◽  
Bernd R Binder
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Human Urine ◽  
Gel Filtration ◽  
Chain Structure ◽  
The Other ◽  
Single Chain ◽  
Apparent Homogeneity ◽  
Sequential Adsorption

SummaryUrokinase (UK) could be purified to apparent homogeneity starting from crude urine by sequential adsorption and elution of the enzyme to gelatine-Sepharose and agmatine-Sepharose followed by gel filtration on Sephadex G-150. The purified product exhibited characteristics of the high molecular weight urokinase (HMW-UK) but did contain two distinct entities, one of which exhibited a two chain structure as reported for the HMW-UK while the other one exhibited an apparent single chain structure. The purification described is rapid and simple and results in an enzyme with probably no major alterations. Yields are high enough to obtain purified enzymes for characterization of UK from individual donors.

Industrial Technology Graduates’ Acquired Skills and Competencies from the University

2019 ◽  
Vol 5 (3) ◽  
pp. 189
Author(s):  
Amado C Gequinto ◽  
Do Mads
Keyword(s):  
Social Media ◽  
Text Messaging ◽  
Global Market ◽  
The Other ◽  
Global Markets ◽  
Industrial Technology ◽  
The University ◽  
Descriptive Method

Skills and competencies are highly regarded in todays global market. Different agencies specifically those seeking for  technologists, technicians, and engineers, have stressed out that skills and competencies as major components  for individual workers.  This aimed to determine  the relevance and appropriateness of acquired skills and competencies by industrial technology graduates, and determine the extent of use of skills and competencies in the current employment. Review of related literatures and studies have been considered in the realization, understanding, analysis, and interpretation of this research exploration. A descriptive method of research was used with 78 graduates from 2015-2016 and 117 graduates from 2016-2017, who participated in the study survey process. The BatStateU Standardized Questionnaire was used to gather data. A brief interview and talk during the visit of alumni in the university was also considered, as well as the other means of social media like email, facebook, messenger, and text messaging.   Results show that skills and competecnices acquired by industrial technology graduates are all relevant and appropriate.  The study also found that there is some to great extent use of acquired skills and competencies to their current employment. The study implies that the acquired skills and competencies from the university significantly provided the graduates the opportunities ins the national and global markets and industries.

scholarly journals Analysis of the Mechanism by Which Glucose Inhibits Maltose Induction of MAL Gene Expression in Saccharomyces

Genetics ◽  
2000 ◽  
Vol 154 (1) ◽  
pp. 121-132
Author(s):  
Zhen Hu ◽  
Yingzi Yue ◽  
Hua Jiang ◽  
Bin Zhang ◽  
Peter W Sherwood ◽  
...  
Keyword(s):  
Gene Expression ◽  
Glucose Repression ◽  
Protein A ◽  
The Other ◽  
Maltose Permease ◽  
Inducer Exclusion ◽  
Glucose Inhibition ◽  
Independent Mechanism ◽  
Mal Genes

Abstract Expression of the MAL genes required for maltose fermentation in Saccharomyces cerevisiae is induced by maltose and repressed by glucose. Maltose-inducible regulation requires maltose permease and the MAL-activator protein, a DNA-binding transcription factor encoded by MAL63 and its homologues at the other MAL loci. Previously, we showed that the Mig1 repressor mediates glucose repression of MAL gene expression. Glucose also blocks MAL-activator-mediated maltose induction through a Mig1p-independent mechanism that we refer to as glucose inhibition. Here we report the characterization of this process. Our results indicate that glucose inhibition is also Mig2p independent. Moreover, we show that neither overexpression of the MAL-activator nor elimination of inducer exclusion is sufficient to relieve glucose inhibition, suggesting that glucose acts to inhibit induction by affecting maltose sensing and/or signaling. The glucose inhibition pathway requires HXK2, REG1, and GSF1 and appears to overlap upstream with the glucose repression pathway. The likely target of glucose inhibition is Snf1 protein kinase. Evidence is presented indicating that, in addition to its role in the inactivation of Mig1p, Snf1p is required post-transcriptionally for the synthesis of maltose permease whose function is essential for maltose induction.

scholarly journals On a New Geometric Constant Related to the Euler-Lagrange Type Identity in Banach Spaces

Mathematics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 116
Author(s):  
Qi Liu ◽  
Yongjin Li
Keyword(s):  
Banach Spaces ◽  
Product Space ◽  
Sufficient Conditions ◽  
Normal Structure ◽  
The Other ◽  
Inner Product ◽  
Equivalent Characterization ◽  
Geometric Constant ◽  
Geometric Constants

In this paper, we will introduce a new geometric constant LYJ(λ,μ,X) based on an equivalent characterization of inner product space, which was proposed by Moslehian and Rassias. We first discuss some equivalent forms of the proposed constant. Next, a characterization of uniformly non-square is given. Moreover, some sufficient conditions which imply weak normal structure are presented. Finally, we obtain some relationship between the other well-known geometric constants and LYJ(λ,μ,X). Also, this new coefficient is computed for X being concrete space.

The development of body and organ shape

BMC Zoology ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Ansa E. Cobham ◽  
Christen K. Mirth
Keyword(s):  
Relative Position ◽  
Body Shape ◽  
Single Cells ◽  
The Other ◽  
Geometric Features ◽  
Main Text ◽  
Size Characterization ◽  
Organ Shape ◽  
The Many

Abstract Background Organisms show an incredibly diverse array of body and organ shapes that are both unique to their taxon and important for adapting to their environment. Achieving these specific shapes involves coordinating the many processes that transform single cells into complex organs, and regulating their growth so that they can function within a fully-formed body. Main text Conceptually, body and organ shape can be separated in two categories, although in practice these categories need not be mutually exclusive. Body shape results from the extent to which organs, or parts of organs, grow relative to each other. The patterns of relative organ size are characterized using allometry. Organ shape, on the other hand, is defined as the geometric features of an organ’s component parts excluding its size. Characterization of organ shape is frequently described by the relative position of homologous features, known as landmarks, distributed throughout the organ. These descriptions fall into the domain of geometric morphometrics. Conclusion In this review, we discuss the methods of characterizing body and organ shape, the developmental programs thought to underlie each, highlight when and how the mechanisms regulating body and organ shape might overlap, and provide our perspective on future avenues of research.

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