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Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

Specialized computational chemistry packages have permanently reshaped the landscape of chemical and materials science by providing tools to support and guide experimental efforts and for the prediction of atomistic and electronic properties. In this regard, electronic structure packages have played a special role by using first-principle-driven methodologies to model complex chemical and materials processes. Over the past few decades, the rapid development of computing technologies and the tremendous increase in computational power have offered a unique chance to study complex transformations using sophisticated and predictive many-body techniques that describe correlated behavior of electrons in molecular and condensed phase systems at different levels of theory. In enabling these simulations, novel parallel algorithms have been able to take advantage of computational resources to address the polynomial scaling of electronic structure methods. In this paper, we briefly review the NWChem computational chemistry suite, including its history, design principles, parallel tools, current capabilities, outreach, and outlook.

Introduction: HF-SCS applied to the ventral surface of the upper thoracic spinal cord (T2 level) results in physiologic activation of both the diaphragm and inspiratory intercostal muscles. Objective: To evaluate the effects of HF-SCS (500Hz, 1mA) applied to the ventral surface of the entire thoracic spinal cord. Material and Methods: In 4 anesthetized dogs, three eight plate stimulation leads, were inserted epidurally and positioned on the ventral surface of the spinal cord via laminectomies at the T6 and T10 levels. Changes in airway pressure (P) were assessed over different regions of the thoracic spinal cord following electrical stimulation (HFSCS: 500 Hz, 1 mA, 0.2ms) at each electrode lead in separate trials, under conditions of airway occlusion and hyperventilation induced apnea. Results: HF-SCS (500Hz, 1mA) resulted in negative P generation over the ventral surface of the entire thoracic spinal cord. Negative P generation was most pronounced at the T2 level (60±2 cmH2O) and T9 levels (46±8 cmH2O). Further examination of HFSCS at the T9 level demonstrated that maximum negative P was dependent upon low stimulus currents (1-3 mA) and high stimulus frequencies (>300 Hz). Both the diaphragm and inspiratory intercostal muscles contributed to negative P generation. Conclusions: The unique findings of the present investigation include the demonstration that spinal circuits which have connections to the inspiratory motoneuron pools exist over the ventral surface of the entire thoracic spinal cord. We postulate that responses are mediated, in part, by stimulation of the previously described intercostal to phrenic excitatory reflex. The large negative P generated at the T9 level suggests that HF-SCS in this region of the spinal cord may be a useful method to restore breathing in ventilator dependent tetraplegics.

We developed a simple three-stage amplifying tunable cw diode laser system that comprises: a Littrow configuration master laser, frequency stabilized with a dichroic atomic vapor laser lock (DAVLL), an acousto-optic frequency shifter (AOM), an injection-locked slave laser and a tapered amplifier (TA). Slave amplifies the frequency-shifted beam and suppresses (within 0.5%) the strong dependence of its intensity on the AOM carrier frequency, thus acting as an efficient optical limiter. The beam is further amplified in TA. System operates at 780 nm, with an output power above 700 mW, a time-averaged linewidth of 0.6 MHz, and a frequency drift below 2 MHz/h. The mode-hop-free tuning range of the master amounts 2 GHz, DAVLL allows a lock point tunability in the range of 400 MHz. The fine (with some tens of kHz precision) tuning range spans 70 MHz, determined by the AOM model applied. A detailed description of the system was given and its performance was tested. The basic components were designed and manufactured in our lab., Comment: 23 pages with 7 figures

A comparison between theory and experiment, concerning the K(4s)+K(7s)\rightarrow K(4s)+K(5f) reaction of energy transfer in thermal collisions, is presented. Relevant cross sections are calculated for the potassium vapour temperatures in the range of 310-1000 K. They are based on the theoretical adiabatic K_2 potential energy curves and on the use of the multicrossing Landau-Zener model. In the temperature range of the present experiment, 428-451 K, the computed cross sections vary little, from 2.09x10^-14 cm^2 to 2.04x10^-14 cm^2, and agree well with the value 1.8(8)x10^-14 cm^2, which is the average of the corresponding experimental results., Comment: 16 pages, 4 figures, research paper

Oxide phases formed at early oxidation stages on unmodified and yttrium-implanted β-NiAl intermetallic compound were studied with the aid of photoluminescence spectroscopy in scales developed at 1473 K for oxidation periods of up to 4 h. Two-stage-oxidation exposures with18O2-tracer were applied. The PLS method was also used to assess the residual stresses in α-Al2O3scale at consecutive stages of its development. It was found that scale formation occurs in a very local way, related to inhomogeneous distribution of Cr in substrate: sometimes distances as short as 10–15 μm were sufficient to observe entirely different phases in the scale. In general, implanted yttrium was found to retard the formation of a stable and protective layer of α-Al2O3. Oxidation for 4 h was necessary for no transient aluminum oxides (mostly θ and/or δ) to be detected, while on non-implanted material they were not found after only 26 min exposure. Only compressive stresses were found in α-alumina scales. They were rather high, reaching even 5 GPa. However, their dependence on the regions in the scale and the scale evolution stage was observed. The results indicate that patches frequently observed in scales on β-NiAl are regions where the phase transformation of transient aluminas to the α phase occurs preferentially. Ridges, which fill the transformation-related cracks, consisted only of α-Al2O3. Combination of these results with those obtained using SIMS distribution analyses of oxygen isotopes as well as with SEM/EDX, enabled very precise conclusions to be inferred concerning the scale growth mechanism. In particular, the local nature of the scale development can be described in more detail. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Evolution of the oxide scale growing at 1000°C as a result of up to 1-hour exposures in air on Fe20Cr5Al + Y2O3 ODS-Type alloy (MA956), was studied using an approach which enabled getting insight into its consecutive stages in terms of the phase and chemical composition, growth mechanism and morphology of the oxide layer. Only CX-Al2O3 oxide was found in the scale for oxidation exposures more prolonged than 2 min. 45 sec. In the case of 2 min. 45 sec oxidation period, a small amount of transient oxide, 6-Al2O3 was detected. Although relatively flat and uniform scale developed under all the studied conditions some Ti-rich oxide particles appear at its surface. Inward growth mechanism predominated at very early oxidation stages. Only for 2 min. 45 sec exposure the oxide was mainly formed near the scale-gas interface rather than in deeper parts of the scale. The residual stresses did not exceed 2.5 GPa and increased by ca. 50% as the exposure proceeded. © Lavoisier, Paris.

Integration af IT i folkeskolens undervisning rummer beskrivelser og diskussioner af de danske resultater af deltagelsen i en international kvalitativ undersøgelse af innovativ pædagogisk praksis. Udgivelsen indeholder seks artikler, der tilsammen beskriver og perspektiverer undersøgelsens resultater. Her præsenteres det internationale forskningskoncept, og det diskuteres, hvorvidt inddragelsen af IT i undervisningen bidrager til at skabe forbedrede betingelser for undervisningsdifferentiering og udvikling af en række moderne kompetencer blandt eleverne. Undersøgelsen perspektiveres ligeledes i forhold til forståelser af barrierer for integration af IT og sammenhænge mellem forskellige forståelser af samfundsudvikling og pædagogik. Udgivelsen indeholder tillige seks forskningsrapporter fra de danske casestudier af forløb og projekter på seks danske folkeskoler.

The dynamics is investigated of a free particle on a sphere (rigid rotor or rotator) that is initially in a coherent state. The instability of coherent states with respect to the free evolution leads to nontrivial time-development of averages of observables representing the position of a particle on a sphere that can be interpreted as quantum beats., Comment: 11 pages, 5 figures

Evolution of coherent states is considered for a particle confined to a cylinder moving in a harmonic oscillator potential. Because of the discontinuous changes as time goes by of the phase representing the position of a particle on a parallel (circle) the trajectory pattern of quantum averages specifying coordinates on a cylinder is very complex and in some aspects resembles chaotic one., Comment: 9 pages, 5 figures

Early oxidation of unmodified and yttrium-implanted or chromium-implanted β-NiAl intermetallic compound at 1473 K was studied using a combination of two-stage-oxidation exposure with 18O2 as a tracer, SIMS elemental distribution analysis (depth profiling and imaging modes) and photoluminescence spectroscopy analysis of the scale phase composition. It was found that phase transformation of transient aluminium oxides, represented by θ- Al2O3 into stable and protective α-Al 2O3 occurs locally and is affected by implanted additions: Yttrium retarded while chromium appeared to accelerate it. Typical patch- and/or web-like scale morphology of the growing scales was observed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

User manual for a web-based tool to help farmers make optimal decisions about nitrogen application in degraded and other lands. LTRA-7 (Pathways to CAPS in the Andes)

We report converged results for the ground and excited states and matter density of 16-O using realistic two-body nucleon-nucleon interactions and coupled-cluster methods and formalism developed in quantum chemistry. Most of the binding is obtained with the coupled-cluster singles and doubles approach. Additional binding due to three-body clusters (triples) is minimal. The coupled-cluster method with singles and doubles provides a good description of the matter density, charge radius, charge form factor, and excited states of a 1-particle-1-hole nature, but it cannot describe the first excited 0+ state. Incorporation of triples has no effect on the latter finding., 4 pages 2 figures

The detailed study of a quantum free particle on a pointed plane is performed. It is shown that there is no problem with a mysterious ``quantum anticentrifugal force" acting on a free particle on a plane discussed in a very recent paper: M. A. Cirone et al, Phys. Rev. A 65, 022101 (2002), but we deal with a purely topological efect related to distinguishing a point on a plane. The new results are introduced concerning self-adjoint extensions of operators describing the free particle on a pointed plane as well as the role played by discrete symmetries in the analysis of such extensions., Comment: 4 figures

TESLA Reports 2001 28 pp. (2001).

It is demonstrated that in contrast to the well-known case with a quantum particle moving freely in a real line, the wave packets corresponding to the coherent states for a free quantum particle on a circle do not spread but develop periodically in time. The discontinuous changes during the course of time in the phase representing the position of a particle can be interpreted as the quantum jumps on a circle., LaTeX, 3 PostScript figures

We present results from MiniMax (Fermilab T-864), a small test/experiment at the Tevatron designed to search for the production of disoriented chiral condensate (DCC) in $p - \bar p$ collisions at $\sqrt{s} = 1.8$ TeV in the forward direction, $\sim 3.4 < ��< \sim 4.2$. Data, consisting of $1.3 \times 10^6$ events, are analyzed using the robust observables developed in an earlier paper. The results are consistent with generic, binomial-distribution partition of pions into charged and neutral species. Limits on DCC production in various models are presented., 24 pages, 9 figures. Minor clarifications have been added

A deformation of the Fock space based on the finite difference replacement for the derivative is introduced. The deformation parameter is related to the dimension of the finite analogue of the Fock space., Comment: LaTeX, 13 pages

The coherent states for a particle on a sphere are introduced. These states are labelled by points of the classical phase space, that is the position on the sphere and the angular momentum of a particle. As with the coherent states for a particle on a circle discussed in Kowalski K {\em et al} 1996 {\em J. Phys. A} {\bf 29} 4149, we deal with a deformation of the classical phase space related with quantum fluctuations. The expectation values of the position and the angular momentum in the coherent states are regarded as the best possible approximation of the classical phase space. The correctness of the introduced coherent states is illustrated by an example of the rotator., LaTeX, 16 pages, 2 figures

A deformation of the Fock space based on the finite difference replacement for the derivative is introduced. The deformation parameter is related to the dimension of the finite analogue of the Fock space., LaTeX, 13 pages

The coherent states for a quantum particle on a circle are introduced. The Bargmann representation within the actual treatment provides the representation of the algebra [(J) over cap, U] = U, where U is unitary, which is a direct consequence of the Heisenberg algebra [, (J) over cap] = i, but it is more adequate for the study of circular motion.

We report on the progress of a search for disoriented chiral condensates (DCCs) in the far forward region at sqrt(s)=1.8 TeV. MiniMax is a small collider experiment situated at the C0 interaction region of the Tevatron and has been designed to measure the ratio of charged to neutral pions produced at eta near 4.1. The distribution of this ratio is expected to be very different for the generic binomial and DCC particle production models. We present a method used for the search using the factorial moments of particle generating functions, which can be extracted directly from the data. A preliminary comparison of robust ratios of measured values and those expected from the different models is also presented., Comment: Latex, 2 figures, 3 pages, To appear in the proceedings of DPF 96.

We speculate that, in very high energy hadronic collisions, large fireballs may be produced with interiors which have anomalous chiral order parameters. Such a process would result in radiation of pions with distinctive momentum and isospin distributions, and may provide an explanation of Centauro and related phenomena in cosmic-ray events. The phenomenology of such events is reviewed, with emphasis on the possibility of observing such phenomena at Fermilab experiment T-864 (MiniMax), or at a Full Acceptance Detector (FAD) at the SSC., Comment: 16 pages, LaTex, figures available on request. hep-ph/yymmnnn

Article published by the Endocrine Society

Theoretical speculations and experimental data suggesting the possibility of observing disoriented chiral condensates at a Full Acceptance Detector are reviewed., Comment: 18 pages, uses phyzzx, CWRUTH-92-6

Increase in maximum groundwater mining resulting from recharge basin usage in the Grand Prairie is reported. Management model incorporates new influence coefficients that describe effect on groundwater levels of simultaneously' occurring basin/aquifer interflow and groundwater extraction.