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WavePacket
(2016)
WavePacket is an open-source program package for the numerical simulation of quantum-mechanical dynamics. It can be used to solve time-independent or time-dependent linear Schrödinger and Liouville–von Neumann-equations in one or more dimensions. Also coupled equations can be treated, which allows to simulate molecular quantum dynamics beyond the Born–Oppenheimer approximation. Optionally accounting for the interaction with external electric fields within the semiclassical dipole approximation, WavePacket can be used to simulate experiments involving tailored light pulses in photo-induced physics or chemistry. The graphical capabilities allow visualization of quantum dynamics ‘on the fly’, including Wigner phase space representations. Being easy to use and highly versatile, WavePacket is well suited for the teaching of quantum mechanics as well as for research projects in atomic, molecular and optical physics or in physical or theoretical chemistry. The present Part I deals with the description of closed quantum systems in terms of Schrödinger equations. The emphasis is on discrete variable representations for spatial discretization as well as various techniques for temporal discretization. The upcoming Part II will focus on open quantum systems and dimension reduction; it also describes the codes for optimal control of quantum dynamics. The present work introduces the MATLAB version of WavePacket 5.2.1 which is hosted at the Sourceforge platform, where extensive Wiki-documentation as well as worked-out demonstration examples can be found.
Hydrologic regionalization deals with the investigation of homogeneity in watersheds and provides a classification of watersheds for regional analysis. The classification thus obtained can be used as a basis for mapping data from gauged to ungauged sites and can improve extreme event prediction. This paper proposes a wavelet power spectrum (WPS) coupled with the self-organizing map method for clustering hydrologic catchments. The application of this technique is implemented for gauged catchments. As a test case study, monthly streamflow records observed at 117 selected catchments throughout the western United States from 1951 through 2002. Further, based on WPS of each station, catchments are classified into homogeneous clusters, which provides a representative WPS pattern for the streamflow stations in each cluster.
The effect of cellulose-based polyelectrolytes on biomimetic calcium phosphate mineralization is described. Three cellulose derivatives, a polyanion, a polycation, and a polyzwitterion were used as additives. Scanning electron microscopy, X-ray diffraction, IR and Raman spectroscopy show that, depending on the composition of the starting solution, hydroxyapatite or brushite precipitates form. Infrared and Raman spectroscopy also show that significant amounts of nitrate ions are incorporated in the precipitates. Energy dispersive X-ray spectroscopy shows that the Ca/P ratio varies throughout the samples and resembles that of other bioinspired calcium phosphate hybrid materials. Elemental analysis shows that the carbon (i.e., polymer) contents reach 10% in some samples, clearly illustrating the formation of a true hybrid material. Overall, the data indicate that a higher polymer concentration in the reaction mixture favors the formation of polymer-enriched materials, while lower polymer concentrations or high precursor concentrations favor the formation of products that are closely related to the control samples precipitated in the absence of polymer. The results thus highlight the potential of (water-soluble) cellulose derivatives for the synthesis and design of bioinspired and bio-based hybrid materials.
The hydrological budget of a region is determined based on the horizontal and vertical water fluxes acting in both inward and outward directions. These integrated water fluxes vary, altering the total water storage and consequently the gravitational force of the region. The time-dependent gravitational field can be observed through the Gravity Recovery and Climate Experiment (GRACE) gravimetric satellite mission, provided that the mass variation is above the sensitivity of GRACE. This study evaluates mass changes in prominent reservoir regions through three independent approaches viz. fluxes, storages, and gravity, by combining remote sensing products, in-situ data and hydrological model outputs using WaterGAP Global Hydrological Model (WGHM) and Global Land Data Assimilation System (GLDAS). The results show that the dynamics revealed by the GRACE signal can be better explored by a hybrid method, which combines remote sensing-based reservoir volume estimates with hydrological model outputs, than by exclusive model-based storage estimates. For the given arid/ semi-arid regions, GLDAS based storage estimations perform better than WGHM.
Watching the Vibration and Cooling of Ultrathin Gold Nanotriangles by Ultrafast X-ray Diffraction
(2016)
We study the vibrations of ultrathin gold nanotriangles upon optical excitation of the electron gas by ultrafast X-ray diffraction. We quantitatively measure the strain evolution in these highly asymmetric nano-objects, providing a direct estimation of the amplitude and phase of the excited vibrational motion. The maximal strain value is well reproduced by calculations addressing pump absorption by the nanotriangles and their resulting thermal expansion. The amplitude and phase of the out-of-plane vibration mode with 3.6 ps period dominating the observed oscillations are related to two distinct excitation mechanisms. Electronic and phonon pressures impose stresses with different time dependences. The nanosecond relaxation of the expansion yields a direct temperature sensing of the nano-object. The presence of a thin organic molecular layer at the nanotriangle/substrate interfaces drastically reduces the thermal conductance to the substrate.
The warm water geothermal reservoir below the village of Waiwera in New Zealand has been known by the native Maori for centuries. Development by the European immigrants began in 1863. Until the year 1969, the warm water flowing from all drilled wells was artesian. Due to overproduction, water up to 50 A degrees C now needs to be pumped to surface. Further, between 1975 and 1976, all warm water seeps on the beach of Waiwera ran dry. Within the context of sustainable water management, hydrogeological models must be developed as part of a management plan. Approaches of varying complexity have been set-up and applied since the 1980s. However, none of the models directly provide all results required for optimal water management. Answers are given simply to parts of the questions, nonetheless improving resource management of the geothermal reservoir.
Waage und Schwert
(2016)
Using both cross-sectional and prospective analyses, this study examined vulnerability factors for sexual victimization in 541 female and male Brazilian college students, of whom a subgroup of 250 took part in two measurements 6 months apart. Risk factors for sexual victimization (alcohol consumption, casual sex, and ambiguous communication) in participants’ cognitive scripts for consensual sex were linked to sexual victimization via their translation into risky sexual behavior. Pornography use was indirectly linked to sexual victimization through its influence on risky sexual scripts and sexual behavior. Child sexual abuse predicted sexual victimization in the cross-sectional analysis, and victimization since age 14 predicted revictimization in the six months covered by the prospective period. Few gender differences were found. This study is the first prospective investigation of vulnerability factors for sexual victimization in Brazil, and similarities to evidence from North America are discussed.
Vorwort der Herausgeberin
(2016)
Von der Demütigung zur Demut
(2016)
Die Rezeption des Propheten Jona im Koran setzt dessen biblischen Narrativ im Wesentlichen voraus und deutet diesen vor allem dort aus, wo man um eine Korrektur seines Prophetenbildes bemüht ist. Im Fokus stehen dabei die Buße, Umkehr und Erlösung Yūnus’ und seines Volkes. Nachkoranische Prophetenerzählungen (qisas alanbiyā’) füllen die narrativen Leerstellen der ‚Jona-Suren‘ wiederum mit erklärendem Erzählmaterial auf und schöpfen dafür auch aus dem umfangreichen Fundus biblischer und rabbinischer Traditionen, die sie sich im äußeren Rahmen der koranischen Yūnus Überlieferung schöpferisch zu eigen machen. So entstehen Erzählkompositionen, die sich als dialogische Auseinandersetzung mit religiösen Themen von gemeinsamer Relevanz lesen lassen. Der Artikel reflektiert gezielt Entwicklung und Verhältnis der Rezeptionen Jonas im Koran sowie in den Prophetenerzählungen von Ibn-Muhammad at-Ta‛labī und Muhammad ibn ‛Abd Allāh al-Kisā’i, in stetiger Auseinandersetzung mit der jüdischen Jona-Tradition.
Aim: We aimed to develop the first references for body height, body weight and body mass index (BMI) for boys based on the individual developmental tempo with respect to their voice break status. Methods: We re-analysed data from the German Health Interview and Examination Survey for Children and Adolescents (KiGGS study) on body height, body weight and body mass index based on the voice break, or mutation, in 3956 boys aged 10-17 years. We used the LMS method to construct smoothed references centiles for the studied variables in premutational, mutational and postmutational boys. Results: Body height, body weight and BMI differed significantly (p < 0.001) between the different stages of voice break. On average, boys were 5.9 cm taller, 5.8 kg heavier and had a 0.7 kg/m(2) higher BMI with every higher stage of voice break. Currently used growth references for chronological age in comparison with maturity-related references led to an average of 5.4% of boys being falsely classified as overweight.
This article explores the practice and political significance of politicians’ journeys to conflict zones. It focuses on the German example, looking at field trips to theatres of international intervention as a way of first-hand knowledge in policymaking. Paying tribute to Lisa Smirl and her work on humanitarian spaces, objects and imaginaries and on liminality in aid worker biographies, two connected arguments are developed. First, through the exploration of the routinized practices of politicians’ field trips the article shows how these journeys not only remain confined to the ‘auxiliary space’ of aid/intervention, but that it is furthermore a staged reality of this auxiliary space that most politicians experience on their journeys. The question is then asked, second, what politicians actually experience on their journeys and how their experiences relate to their policy knowledge about conflict and intervention. It is shown that political field trips enable sensory/affectual, liminoid and liminal experiences, which have functions such as authority accumulation, agenda setting, community building, and civilizing domestic politics, while at the same time reinforcing, in most cases, pre-existing conflict and intervention imaginaries.
The central rift of the Red Sea has 25 brine pools with different physical and geochemical characteristics. Atlantis II (ATIID), Discovery Deeps (DD) and Chain Deep (CD) are characterized by high salinity, temperature and metal content. Several studies reported microbial communities in these brine pools, but few studies addressed the brine pool sediments. Therefore, sediment cores were collected from ATIID, DD, CD brine pools and an adjacent brine-influenced site. Sixteen different lithologic sediment sections were subjected to shotgun DNA pyrosequencing to generate 1.47 billion base pairs (1.47 x 10(9) bp). We generated sediment-specific reads and attempted to annotate all reads. We report the phylogenetic and biochemical uniqueness of the deepest ATIID sulfur-rich brine pool sediments. In contrary to all other sediment sections, bacteria dominate the deepest ATIID sulfur-rich brine pool sediments. This decrease in virus-to-bacteria ratio in selected sections and depth coincided with an overrepresentation of mobile genetic elements. Skewing in the composition of viruses-to-mobile genetic elements may uniquely contribute to the distinct microbial consortium in sediments in proximity to hydrothermally active vents of the Red Sea and possibly in their surroundings, through differential horizontal gene transfer.
Der vorliegende Beitrag gibt einen Überblick über das Thema „Gewalt an Schulen“ und verknüpft es mit gesundheitlichen Aspekten von Schülerinnen und Schülern. Ausgehend von der Annahme, dass Gewalt und Gesundheit zwei Seiten einer Medaille sind, wird der Frage nachgegangen, wie sich Gewalt- und Mobbingphänomene an deutschen Schulen entwickelt haben und welche Zusammenhänge es zur Gesundheit von Schülerinnen und Schülern gibt. Die empirische Basis bilden langjährige Untersuchungen der Autoren, u. a. im Rahmen der internationalen Studie „Health Behaviour in School-aged Children“ (HBSC). Auf der Basis eigener empirischer Studien werden Prävalenzen und Strukturen der Schülergewalt sowie der Zusammenhang von Gewalt und Gesundheit verdeutlicht und Folgerungen für die Gewalt- und Gesundheitsprävention gezogen. Entgegen dramatisierender Einschätzungen in den Medien zeigt sich, dass in den letzten Jahren eine kontinuierliche Verringerung der Mobbing-Problematik an deutschen Schulen zu verzeichnen ist. Mit Blick auf den Zusammenhang von Gewalt und Gesundheit lässt sich ein signifikanter Zusammenhang zwischen dissozialem Verhalten und Parametern der Gesundheit belegen. So weisen Opfer und Täter-Opfer die größten und Unbeteiligte die geringsten gesundheitlichen Probleme auf, während für Täter – entgegen gängiger Annahmen – eher eine positive Grundstimmung kennzeichnend ist. Aufgrund des engen Zusammenhangs von Gewalt und Gesundheit wird die Folgerung abgeleitet, Gewaltprävention- und Gesundheitsförderung mit Schulentwicklung und Schulprogrammarbeit zu verbinden, um nachhaltige Präventionswirkung zu erzielen.
The article gives an overview of violence at school combined with the health of students. Based on the assumption that violence and health are two sides of the same coin, the article considers the question of the development of violence and bullying phenomena at German schools and its relation to student health. Long-term studies by the authors, such as the international Health Behavior in School-aged Children (HBSC) study, constitute the empirical basis. Prevalence and structures of student violence, as well as the relation between violence and health, are clarified and consequences for the prevention of violence and health are shown on the basis of our own empirical studies. Contrary to dramatic estimates in the media, a continuous reduction of bullying problems at German schools has been registered in recent years. In reference to the relation between violence and health, a significant correlation between dissocial behavior and health parameters was found. Victims and bully-victims show the most health problems and innocent bystanders the least health problems. In contrast to previous findings, bullies show a more positive prevailing mood. Due to the found associations between violence and health, it appears reasonable to combine violence prevention and health promotion measures to achieve sustainable prevention effects.
Context. For the spectral analysis of high-resolution and high signal-to-noise (S/N) spectra of hot stars, state-of-the-art non-local thermodynamic equilibrium (NLTE) model atmospheres are mandatory. These are strongly dependent on the reliability of the atomic data that is used for their calculation. Aims. New Kr IV-VII oscillator strengths for a large number of lines enable us to construct more detailed model atoms for our NLTE model-atmosphere calculations. This enables us to search for additional Kr lines in observed spectra and to improve Kr abundance determinations. Methods. We calculated Kr IV-VII oscillator strengths to consider radiative and collisional bound-bound transitions in detail in our NLTE stellar-atmosphere models for the analysis of Kr lines that are exhibited in high-resolution and high S/N ultraviolet (UV) observations of the hot white dwarf RE 0503-289. Results. We reanalyzed the effective temperature and surface gravity and determined T-eff = 70 000 +/- 2000 K and log (g/cm s(-2)) = 7.5 +/- 0.1. We newly identified ten Kr V lines and one Kr vi line in the spectrum of RE 0503-289. We measured a Kr abundance of 3.3 +/- 0.3 (logarithmic mass fraction). We discovered that the interstellar absorption toward RE 0503-289 has a multi-velocity structure within a radial-velocity interval of -40 km s(-1) < upsilon(rad) < +18 km s(-1). Conclusions. Reliable measurements and calculations of atomic data are a prerequisite for state-of-the-art NLTE stellar-atmosphere modeling. Observed Kr V-VII line profiles in the UV spectrum of the white dwarf RE 0503-289 were simultaneously well reproduced with our newly calculated oscillator strengths.
The valence-excited states of ferric and ferrous hexacyanide ions in aqueous solution were mapped by resonant inelastic X-ray scattering (RIXS) at the Fe L-2,L-3 and N K edges. Probing of both the central Fe and the ligand N atoms enabled identification of the metal-and ligand-centered excited states, as well as ligand-to-metal and metal-to-ligand charge-transfer excited states. Ab initio calculations utilizing the RASPT2 method were used to simulate the Fe L-2,L-3-edge RIXS spectra and enabled quantification of the covalencies of both occupied and empty orbitals of pi and sigma symmetry. We found that pi back-donation in the ferric complex is smaller than that in the ferrous complex. This is evidenced by the relative amounts of Fe 3d character in the nominally 2 pi CN- molecular orbital of 7% and 9% in ferric and ferrous hexacyanide, respectively. Utilizing the direct sensitivity of Fe L-3-edge RIXS to the Fe 3d character in the occupied molecular orbitals, we also found that the donation interactions are dominated by sigma bonding. The latter was found to be stronger in the ferric complex, with an Fe 3d contribution to the nominally 5 sigma CN- molecular orbitals of 29% compared to 20% in the ferrous complex. These results are consistent with the notion that a higher charge at the central metal atom increases donation and decreases back-donation.