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One cannot not communicate, says one axiom of Paul Watzlawick and emphasizes, that everything we do and everything we leave is a message to one’s counterpart. Where communication takes place conflict is close. From misunderstanding to war, from communication refusal to a communication overload: The combination of communication and conflict has different developments. The current book presents various facts of this combination. From an analysis of communicative conflict resolution of the Israel-Palestine-Conflict on Facebook, instances of leadership and communication in the literature of operation Iraqi freedom, political iconoclasm in the digital age on the basis of the death of Osama bin Laden, a social identity perspective on communication about errors in organisations, the overload with online communication at business, how conflict management training works, strategies in the communication of political violence to the influence of mass media on the course of contemporary military conflicts.
The continuous optimization of business processes is becoming an increasingly important factor for a company’s long-term success. Maturity models for business processes aim at maintaining a distinct quality of processes and help to determine the maturity level of the processes and the company’s maturity. Previous research has shown the lack of transparency and standardization for maturity models. In particular, existing maturity models were not scientifically compared and evaluated among themselves. Uncertainty and unawareness in selection and application of adequate
maturity models can be observed in applied science and practice. The aim of the scientific work was to evaluate existing business process maturity models in terms of strengths and weaknesses in order to provide a comprehensive and reliable knowledge-based on specific evaluation criteria setting. The conclusions have been used to take advantage of one of the pre-chosen models to measure the maturity of a business process. The examined models were CMMI, BPMM-OMG, PEMM and EDEN. The applied methodology consists of literature research, empirical findings and practical application. The empirical findings comprise a purpose-made questionnaire and an outcome weighted in terms of importance and / or appliance. A particular challenge of the research
was to compare the different maturity models based on their criteria, scales and general scope.
Due to the influence of a strong electromagnetic field an induced gap is expected to occur in the band structure of a semiconductor. In this paper the influence of the damping by electron–phonon collisions and by recombination on the new band structure is investigated. Taking into account damping kinetic equations for the electrons are derived and discussed with the help of calculations.
Unter dem Einfluß eines starken elektromagnetischen Feldes kommt es in der Bandstruktur eines Halbleiters zur Ausbildung eines Zusatzgaps. In dieser Arbeit wird der Einfluß der Dämpfung durch Elektron–Phononstöße und Rekombination auf die neue Bandstruktur untersucht. Weiterhin werden kinetische Gleichungen unter Berücksichtigung der Dämpfung abgeleitet und an Hand von numerischen Berechnungen diskutiert.
Kinetic problems for off-resonance excitation (dynamical Stark effect) and resonant excitation (laser-induced gaps) are studied. Within the Hartree-Fock theory, Stark shift and bleaching of the exciton line are evaluated. The influence of photon statistics on light-induced gaps is investigated. Open questions concerning the transient response are clarified.
Es werden kinetische Probleme für nichtresonante Anregung (dynamischer Stark-Effekt) und resonante Anregung (laserinduzierte Lücken) betrachtet. Im Rahmen der Hartree-Fock-Theorie werden Stark-Verschiebung und Oszillatorstärkenänderung für die Exzitonlinie berechnet. Der Einfluß der Photon-Statistik auf die lichtinduzierten Lücken wird untersucht. Einige offene Fragen des Kurzzeit-Response werden geklärt.
The dynamical Stark effect of excitons in CdS bulk crystals has been measured recently using differential transmission spectroscopy (DTS). A general DTS formula is derived taking into account exciton-exciton interaction. A perculiar influence of the pump and test polarization on its magnitude is predicted. Concerning the dephasing (transverse relaxation), coupling to optical phonons is treated on a microscopic level. A density-matrix approach leads to the imaginary part of the exciton-phonon self energy. Its strong frequency dependence which shows up as a non-Markoff relaxation strongly suppresses the relaxation for the pump pulse at large detuning. A more sophisticated approach using the non-equilibrium Green function gives deeper insight into the underlying scattering processes.
Kinetic equations for the density correlation and density-density response function are derived. Solving these equations numerically and comparing its solution with the adiabatic approximation the change in the transmitted spectrum of a single electronic transition is calculated where a red-shift can be observed.
Es werden kinetische Gleichungen für die Di Dichtekorrelationsfunktion und die Dichte-Dichte-Responsefunktion abgeleitet. Die numerische Lösung dieser Gleichungen wird mit der adiabatischen Approximation verglichen. Die Berechnung der Änderung im Transmissionsspektrum für einen einzelnen elektronischen Übergang ergibt eine Rotverschiebung.
Starting from the kinetic equations for the nonequilibrium Green's functions, a practical method is proposed which allows to solve the set of equations for the two-time propagators numerically. In contrast to the usual semiconductor Bloch equations with phenomenological damping relaxation and dephasing processes are treated microscopically for the case of coupling to a bath of LO-phonons. Beside a standard approximation for the treatment of LO-phonon scattering, no further approximations are performed. For the low-density limit we compare exact results with approximate treatments, as the Marcovian and non-Marcovian approximations resulting from a density matrix approach. First results concerning nonlinear optical properties are presented.
We report a strong (300:1) excitonic resonance in time-resolved (100 fs) four-wave mixing in GaAs quantum wells as a function of the incident photon energy and show that it results from the large difference in the dephasing rates of excitons and free carriers. We conclude that excitons dominate even when they make up only a small fraction of the excited states. These results, in conjuction with new results in exciton-phonon scattering, provide new insights into previous studies performed with spectrally broad ultrashort pulses.
The aim of this paper is to investigate the motivations that lead higher education students to replace several Learning Management Systems (LMS) services with cloud file hosting services for information sharing and collaboration among them. The research approach is based on the Technology Acceptance Model (TAM). More specifically, the model is devoted to identifying barriers and enablers to the acceptance of these technologies. A questionnaire comprising three factors (Attitude toward using technology, Perceived ease of use and Perceived usefulness) was applied to a sample consisting of 121 higher education students. Results show that the
perceived ease of use of cloud file hosting services is above that of LMS tools and services and that cloud file hosting services presented higher levels of perceived usefulness than standard learning management tools. In addition, attitude toward using cloud file hosting services is well above that of using LMS tools.
The Common European Sales Law (CESL) is the European Commission’s most recent policy initiative for European contract law. It aims to address the problem that differences between the national contract laws of the Member States may constitute an obstacle for the European Internal Market. This paper develops a model of the institutional competition in European contract law and uses it to addresses the question as to whether an optional European contract code and the CESL are economically desirable for European contract law. To do so I examine the transaction costs involved in the process of choosing an applicable law that European businesses face when they conduct cross-border transactions in the European Internal Market. I then describe how these transaction costs shape the competitive environment, i.e. what I refer to as the “European market for contract laws” in which the contracting parties choose a law to govern their cross-border contracts. Having identified this environment and the competitive forces operating within it, I propose a model, the “Cycle of European Contract Law”. I use this model to analyze the competitive processes that take place in the European market for contract laws. Based on my results I make recommendations for the optimal implementation of an optional European contract code and the CESL in European contract law.
Information overload is becoming bigger as internet grows. This entails several problems such as difficulty in finding information and redundancy of knowledge. In this paper, a solution of these problems is presented as a global representation of knowledge based on human perception, and modelled by means of ontologies. In this study we present the approach with several advantages as well as some drawbacks related to state of the art technologies.
Time‐resolved four wave mixing (4WM) signals of conjugated polymers are calculated using a density matrix approach and the Hartree–Fock approximation. The influence of the Coulomb interaction as well as size effects on the nonlinear optical response are examined. For the Hückel model (no Coulomb interaction), quantum beats due to the coherent excitation of several band states are found for small sizes, and photon echo‐like behavior is obtained for infinite size. The Coulomb interaction changes the nature of the response and gives rise to a broad delayed signal whose temporal profile is determined by the dephasing time.
The optical response of conjugated polymers is calculated using a one-dimensional tight-binding model with Coulomb interactions, and adopting the multipolar form for the electromagnetic field Hamiltonian. By formulating the problem using the reduced single-electron density matrix and its evolution in Liouville space, we obtain a real-space description for the elementary electronic excitations. A unified expression for the linear response including radiative decay, which is valid for arbitrary chain size compared with the optical wavelength, is described. For small sizes it shows exciton confinement effects on the radiative decay and for larger sizes it fully incorporates polariton effects.
We introduce a concept which allows to study the nonlinear optical response of conjugated polymers taking into account many-body effects of the excitation process. The formation of charge transfer excitons and the creation of lattice distortions are studied in short polymer chains by solving the self consistent equations of motion for the reduced single electron density matrix and the lattice displacement. The coupling of electronic motions to lattice dynamics gives rise to the formation of excitonic polarons, which can be identified in the femtosecond pump-probe signal.
We have investigated the optical excitation of solitons and charge transfer excitons in polymer chains by solving the equations of motion for the reduced density matrix and the lattice displacement simultaneously in time. Electron-phonon coupling leads to polaron-exciton formation which can be identified in transient pump-probe signals.
We present an exactly diagonalizable model Hamiltonian for the large polaron derived by analyzing the variational ansatz by Haga-Larsen (HL) for the Fröhlich Hamiltonian. The lowest energy eigenvalue of the model Hamiltonian for fixed wave numbers reproduces the energy of the variational ansatz by Haga-Larsen and is, therefore, an upper bound with respect to the corresponding energy eigenvalue of the Fröhlich Hamiltonian. This is valid for any momentum which is proven by extending the Haga-Larsen approach. Furthermore, since all integrations can be performed analytically, the model Hamiltonian is easily tractable. The energy eigenvalue spectrum of the model Hamiltonian is studied below and above the phonon-emission threshold. The quality of the model Hamiltonian is determined by the variational ansatz of Haga and Larsen. Incorporating an improved energy-momentum relation, a generalized model Hamiltonian is derived possessing a larger validity range with respect to the coupling strength. Furthermore, a second exactly diagonalizable model Hamiltonian based on improved Wigner-Brillouin perturbation theory due to Warmenbol, Peeters, and Devreese (WPD) is presented. It is briefly demonstrated that one is able to construct all mentioned model Hamiltonians also in the 2D polaron problem. In contrast to the 3D case, where the HL-type model Hamiltonian possesses the higher quality for any momentum, in the 2D case, it works well only for small momenta. For large momenta, only the WPD-type model Hamiltonian describes the energy-momentum relation correctly. We demonstrate the usefulness of the model Hamiltonian concept by exactly calculating the one-electron Green’s function for all mentioned model Hamiltonians and comment why significant advantages of the model Hamilton concept for the treating of low-dimensional systems (planar semiconducting quantum-well structures) can be expected.
In a virtualized business world leadership relations are shifting noticeably towards “remote leadership” where leadership is conducted mainly through modern communication technology to cope with physical distance between leaders and employees. Against this background, many academic scholars are suggesting that transformational leadership is an appropriate leadership style to manage effectively in a remote context. Surprisingly, the trend in practice seems to go in the opposite direction. Based on an empirical study of remote leaders in action, we diagnosed an increasing usage of the “transactional toolbox”– management by objectives, management by exceptions, performance measurement, controlling and planning systems. From an academic standpoint this biasn reveals a completely unexpected development in leadership behaviour. Thus, in our article we try to shed light on this opposing trend.
Ab-initio study of structural and optical properties of nonstoichiometric alkalimetal- oxides
(1997)
Structural and optical properties of nonstoichiometric LinO and NanO (n = 3, 4) clusters containing one and two excess electrons are studied using ab-initio methods accounting for electron correlation. We show that calculated absorption patterns are excellent fingerprints of structural and bonding properties. The optical response of Li4O and Na4O clusters with the most stable tetrahedral type structures is characterized by a common feature, that is the appearance of a dominant intense transition in infrared regime although excess of electrons are not localized, as it is the case for small alkali-halide clusters, with cuboid corner vacancy (surface F-center in finite systems).
We investigate ultrafast multi-state nuclear dynamics in a triatomic cluster. In particular, we explore how the intracluster nuclear dynamics of the Ag−3/Ag3/Ag+3 system is reflected in the femtosecond pump-probe negative ion-to neutral-to positive ion (NENEPO) signals. The nuclear dynamics is based on classical trajectories on the ground electronic adiabatic state potential hypersurfaces obtained from accurate ab initio quantum chemistry calculations. The nuclear dynamics of Ag3 initiated from the linear transition state involves distinct sequential processes of configurational relaxation to the triangular configuration, intracluster collisions, and the onset of IVR, resonant, and dissipative IVR, and vibrational equilibration. We determined the timescales for these processes and discussed their dependence on the initial cluster temperature. The Wigner representation of the density matrix was utilized to simulate the NENEPO-zero kinetic energy (NENEPO-ZEKE) signal and the total (integrated over the photoelectron energy) NENEPO signal. We show how geometrical change, completion of IVR and vibrational coherenceeffects can be identified in the NENEPO signals. A comparison of the calculated NENEPO signals with the available experimental data is presented.
The central issue in femtosecond (fs) time resolved spectroscopy of clusters is the investigation of geometric relaxation and internal vibrational redistribution (IVR) after optical excitation in a nonequilibrium configuration of nuclei by laser photoelectron excitation, and corresponding time delayed probing by multiphoton-ionization. For this purpose, we have developed multistate ab initio molecular dynamics involving adiabatic ground and excited electronic states, as well as nonadiabatic coupling between them, using the time evolution of initial thermal ensemble in Wigner representation. The combination of ab initio quantum chemical methods, used for the adiabatic and nonadiabatic molecular dynamics “on the fly,” and the Wigner distribution approach for the description of the motion of the nuclei allowed us the accurate determination of pump-probe and pump-dump signals also under temperature dependent initial conditions. The connection between simulated pump-probe signals and the underlying dynamics of nuclei involving adiabatic electronic ground states has been first established for the example of the Agequation image/Ag3/Agequation image systems, and compared with experimental negative-to-neutral-to-positive NeNePo pump-probe signals. Our simulations reproduced the experimental NeNePo results and determined, in addition to the timescales of geometric relaxation, the conditions under which the resonant or dissipative IVR, as well as vibrational coherence, should be found in the experimental pump-probe signals. This can be realized in the zero electron kinetic energy NeNePo-ZEKE experiments, which are in progress. The above combination of methods has been recently extended to the analysis of the timescales as well as of the dynamics in excited electronic states of the nonstoichiometric NanFn−1 (n=2–4) clusters with the single excess valence electron. Our approach allows the simulation of femtosecond NeExPo-pump-probe and NeExNe-pump-dump signals, based on an analytic formulation which utilizes temperature dependent ground state initial conditions of neutral system (Ne); an ensemble of trajectories carried out either on the adiabatic electronic excited state (Ex), or on both the excited and the ground states through nonadiabatic coupling in connection with the fewest switching hopping algorithm for the investigation of the dynamics of the system; and either the cationic (Po) or the neutral ground state (Ne) for the probing step. The choice of the systems has been made in order to determine the timescales of processes involving (1) fast geometric relaxation leaving the bonding frame intact versus IVR, as during the adiabatic dynamics in the first excited state of Na4F3, being the smallest prototype of F-colored centers in the bulk; and (2) the photo-isomerization process through the conical intersection during nonadiabatic dynamics due to the long amplitude motion, as in the Na3F2 cluster after breaking of one metallic and one ionic bond, representing the first example of a five atomic cluster in the gas phase exhibiting conical intersection between the ground and the first excited state. In both cases, full complexity of the problem has been considered taking into account all degrees of freedom. The investigated systems represent important test cases for providing the conceptual framework of ultrafast dynamics in finite systems.
Stationary spectra offer information on the interplay between the structures and the nature of electronic excitations reflecting bonding properties, as shown by comparing Sin with Agn (n=4-6) clusters. In order to study the dynamical properties, simulations and analysis of femtosecond (fs) time-resolved pump–probe or pump–dump signals have been carried out, which allows us to determine the timescales and the nature of configurational changes versus internal vibrational relaxation (IVR) in electronic ground or excited states. For this purpose we have developed a multi-state ab initio molecular dynamics (involving ground as well as adiabatic or non-adiabatic excited electronic states) on the timescale of the nuclear motion, using the time evolution of a thermal ensemble in the Wigner representation. The combination of ab initio quantum-chemical methods used for the molecular dynamics ‘on the fly’ and the Wigner-distribution approach for the description of the motion of the nuclei also allowed the accurate determination of pump–probe and pump–dump signals under temperature-dependent initial conditions. We use this novel combination of methods to investigate the dynamics in excited states of non-stoichiometric NanFn-1 clusters with a single excess electron. The timescales of the structural relaxation in excited states versus intramolecular vibrational relaxation processes have been determined, as illustrated for the example of Na4F3. This is the first study of the system with 15 degrees of freedom for which the dynamics in the excited states has been carried out without the precalculation of the energy surfaces.
We present a theoretical study of the multistate dynamics of the Ag3-/Ag3/Ag3+ system on the time scale of nuclear motion, as explored by femtosecond pump−probe negative ion-to neutral-to positive ion (NENEPO) spectroscopy. The dynamics of the Ag3 cluster initiated from its linear transition state involves configurational relaxation, intracluster collision, and onset of IVR, resonant and dissipative IVR and vibrational equilibration, whose time scales were determined. Our analysis reveals that theory is essential for the elucidation of the rich dynamic information regarding geometrical change, completion of IVR, and vibrational coherence effects in the NENEPO femtosecond signals.
Theoretical study of femtosecond pump–probe signals of nonstoichiometric alkali halide clusters
(1999)
We present the outline of the ab–initio molecular dynamics method for adiabatic excited states which is suitable to treat the involved excited electronic states simultaneously with the motion of the nuclei. The method allows the simulation of time–resolved pump–probe signals and the analysis of the signals in terms of the underlying nuclear dynamics. Moreover, the timescales of the structural relaxation in excited electronic states vs. intramolecular vibrational relaxation processes can be estimated and the influence of the initial temperature of the cluster can be determined.
The method is applied to the analysis of the timescales as well as of the dynamics of localized/delocalized electronic excitations in the Na2F molecule which represents a test example for nonstoichiometric alkali–halides with one excess electron. The aim is to develop a method for the investigation of time–dependent laser induced processes in clusters which is capable to extract the leading physical effects responsible for the controlled excitation dynamics and for the evolution of the non–equilibrium states.
The first three-dimensional quantum-dynamical ab initio simulation of the large amplitude vibrational dynamics of an Ag3 cluster initiated from its linear transition state is presented. This can be monitored by femtosecond pump-probe negative-ion to neutral-to-positive-ion spectroscopy with zero electron kinetic energy (NeNePo-ZEKE). The time evolution of the representative wavepacket confirms the dynamical effects which have been discovered previously by Wigner-type semiclassical simulations: the initial coherent bending and stretching from linear to near equilateral triangular configuration, followed by intracluster collision and intracluster vibrational relaxation with a weak fractional revival. In addition, the quantum wavepacket shows interferences and spreading.
Gesundheitsmanagement
(2012)
We investigate the ultrafast multistate nuclear dynamics involving adiabatic electronic excited states of nonstoichiometric halide deficient clusters (NanFn−1) characterized by strong ionic bonding and one excess electron, which is localized either in the halide vacancy or on the alkali atom attached to the ionic subunit depending on the cluster size. For this purpose we developed an ab initio adiabatic nuclear dynamics approach in electronic excited and ground states “on the fly” at low computational demand by introducing the “frozen ionic bonds” approximation, which yields an accurate description of excited states considering the excitation of the one excess electron in the effective field of the other n−1 valence electrons involved in the ionic bonding. We combined this multistate dynamics approach with the Wigner–Moyal representation of the vibronic density matrix forming the ab initio Wigner distribution approach to adiabatic dynamics. This method allows the simulation of femtosecondNeExPo-pump–probe and NeExNe-pump–dump signals based on an analytic formulation which utilizes temperature-dependent ground-state initial conditions (Ne), an ensemble of trajectories carried out on the electronic excited state (Ex) for the investigation of the dynamics of the system, and either the cationic (Po) or the ground state (Ne) for the probing step. The choice of the systems has been made in order to determine the time scales of processes involving (i) metallic bond breaking such as during the dynamics in the first excited state of Na2F, and (ii) fast geometric relaxation leaving the bonding frame intact as during the dynamics in the first excited state of Na4F3. The bond-breaking process via a conical intersection involving nonadiabatic dynamics will be presented in the accompanying paper [Hartmann et al., J. Chem. Phys. 114, 2123 (2001)]. The dynamics in the first excited state of Na2F from triangular-to linear-to triangular structure gives rise to fast geometric relaxation due to Na–Na bond breaking at the time scale of ∼90 fs but no signature of internal vibrational energy redistribution (IVR) is present in NeExNe-pump–dump signals since the broken metallic bond prevents the coupling between stretching and bending modes. Instead, anharmonicities of the bending periodic motion have been identified. In contrast, in the case of Na4F3, which is the smallest finite system for a surface F-center prototype of bulk color centers, after the geometric relaxation in the excited state of ∼100 fs leading to the deformed cuboidal type of structure without breaking of bonds, different types of IVR have been identified in NeExNe signals by tuning the dump laser: one-mode selective energy leaving IVR, resonant, and restricted energy arriving IVR corresponding to the selection of different parts of the phase space. Dissipative IVR could not be identified in NeExNe signals of Na4F3 at low initial temperature on the time scale up to 2 ps in spite of 15 degrees of freedom. Due to similar structural and electronic properties such as F centers in bulk, these findings can serve as guidance for establishing the time scales for geometric relaxation and IVR in excited states of larger systems.
Zielsetzung: Die Zielsetzung der vorliegenden Studie war es, die Machbarkeit der Erhebung der Zahlungsbereitschaft über soziale Netzwerke, hier Facebook, am Beispiel des Darmkrebs-Screenings zu untersuchen. Bei dem beschriebenen neuen diagnostischen Test handelt es sich um den neuartigen molekularen Bluttest Septin9, der im Vergleich zu standardmässig für Routinescreening auf Darmkrebs eingesetzten Test auf okkultes Blut im Stuhl (FOBT) eine bessere Performance, eine bessere Handhabbarkeit und eine bessere Compliance von Patienten und Ärzten aufweist.
Methodik: Es wurden Informationen zum Krankheitsbild und den alternativen Screeningmethoden für Darmkrebs gegeben. Die Zahlungsbereitschaft wurde in binären Kategorien (<100 oder >100 EUR) und als Höchstbetrag erfasst. Die weiteren Parameter wie Alter, Geschlecht, Versicherten- und Einkommensstatus, Ernährung, Kontakt mit Krebserkrankungen und gesundheitsbewusstes Verhalten (Alkohol, Rauchen) wurden in Kategorien erfasst. Die Befragung wurde von sechs Facebook-Accounts an insgesamt rund 500 Nutzer des sozialen Netzwerks mit der Möglichkeit der weiteren Distribution versandt. Die Beantwortung eines Kern-Teils der Fragen wurde als Bedingung für die anonyme Einsendung über einen Dropbox-Link vorausgesetzt. Der Rücklaufzeitraum betrug 14 Tage.
Ergebnisse: Es gingen 123 komplett ausgefüllte Fragebögen ein. Die Teilnehmer waren im Schnitt 24,2 Jahre und verdienen zu 94 % weniger als 1500 EUR monatlich. 27 % der Teilnehmer sind privat versichert. 68% gaben an in der Familie von Krebs betroffen zu sein und 36 %, dass sie sich der Gefahr von Darmkrebs bewusst sind. Die Angaben zum wichtigsten Attribut eines Screening-Tests verteilten sich folgendermaßen: 69 % Testgenauigkeit, 14 % Handling, 11 % Preis und 6% Schnelligkeit des Ergebnisses. 24 % gaben eine Zahlungsbereitschaft von weniger als 100 EUR an (Mittelwert 34 EUR), 76 % waren bereit mehr als 100 EUR zu bezahlen. Die durchschnittliche Zahlungsbereitschaft lag bei 271 EUR. Ein höheres Einkommen, eine Krebserkrankung in der Familie und ein Privatversichertenstatus waren mit einer höheren Zahlungsbereitschaft korreliert.
Schlussfolgerung: Eine Messung der Zahlungsbereitschaft sowie weiterer die Patientenpräferenzen beschreibender Variablen ist über soziale Netzwerke mit vergleichsweise geringem Aufwand möglich. Vorteile liegen in der Freiwilligkeit und der Anonymität der Erhebung, wodurch direkte, nicht standardisierte Beeinflussungsmöglichkeiten während der Befragung als Bias wegfallen. Nachteile liegen in der sicherlich starken Selektion der Zielgruppe, was zu einer Einschränkung der Anwendbarkeit der Methode führt.
We present a theoretical study of a femtosecond photo isomerization process due to a nonadiabatic radiationless decay from the first excited state through a conical intersection occurring in one of the nonstoichiometric halide-deficient clusters with one excess electron (Na3F2). This is an extension of the adiabatic dynamics study presented in the accompanying paper [J. Chem. Phys. 114, 2106 (2001)] for other members of the NanFn−1 series characterized by a strong ionic bonding for which the “frozen ionic bonds” approximation has been justified, allowing consideration of the optical response of the single excess electron in the effective field of the other electrons. In this contribution we outline the extension of the ab initio Wigner-distribution approach to nonadiabatic molecular dynamics which combines the Wigner–Moyal representation of the vibronic density matrix with the ab initio multistate molecular dynamics in the ground- and excited electronic states including the nonadiabatic coupling computed “on the fly” in connection with the fewest-switches hopping algorithm. This scheme allows accounting for temperature-dependent initial conditions, for the propagation in the excited state and in the ground state after the passage through the conical intersection, and for probing in the cationic ground state as well as for deriving analytic expressions for the pump–probe signals which utilize an ensemble of classical trajectories obtained at low computational demand. Our approach permits investigation of the photo isomerization through the conical intersection due to the long amplitude motion in the Na3F2 system in full complexity, taking into account all degrees of freedom. After breaking of one metallic and of one ionic bond the conical intersection occurs at the linear geometry and involves states of different symmetry which differ in the translocation of the one excess electron or positive charge localized at the Na atom from one end to the other of the system and separates two isomers with Cs and C2v structures. From the analysis of the nonadiabaticdynamics, the time scales for the metallic bond breaking of ∼90 fs and for the ionic bond breaking of ∼220 fs, for the passage through the conical intersection after ∼0.4 ps and for the internal vibrational energy redistribution (IVR) of more than 0.9 ps for the individual isomers, have been determined. The simulated fs pump–probe signals confirm the above results and provide the information about the experimental conditions such as laser frequencies and pulse duration under which bond breaking of different type as well as the population of each of the two isomers after the passage through the conical intersection can be identified. In this contribution we show that the mechanism of the photo isomerization at a conical intersection due to a long amplitude motion can occur in atomic clusters and is not necessarily limited to organic photochemistry.
Ultrafast ground state nuclear dynamics of Au4 and Ag4 is theoretically explored in the framework of negative ion - to neutral - to positive ion (NeNePo) pump-probe spectroscopy based on the ab initio Wigner distribution approach. This involves the preparation of a nonequilibrium neutral ensemble by pump induced photodetachment of a thermal anionic ground state distribution, gradient corrected DFT classical trajectory simulations "on the fly" on the neutral ground state, and detection of the relaxation process of the ensemble in the cationic ground state by a time-delayed probe pulse. In Au4, the initially prepared linear structure is close to a local minimum of the neutral state giving rise to characteristic vibrations in the signals for probe wavelength near the initial Franck-Condon transition. A timescale of ~1 ps for the structural relaxation towards the stable rhombic D neutral isomer was determined by the increase of the signal for probe wavelength in vicinity of the vertical ionization energy of the rhombic structure. In contrast, the relaxation dynamics in Ag4 is characterized by normal mode vibrations since both the initially prepared anionic ground state and the neutral ground state have rhombic minimum geometries. Thus, time-resolved oscillations of pump-probe signals are fingerprints of structural behaviour which can be used experimentally for the identification of particular isomers in the framework of NeNePo spectroscopy.
We present the ultrafast multistate nuclear dynamics involving adiabatic and nonadiabatic excited states of non-stoichiometric halide deficient clusters (NanF) characterized by strong ionic bonding and one-excess electron for which the "frozen ionic bonds" approximation has been justified allowing to consider the optical response of the single excess electron in the effective field of the other electrons. We combined the Wigner-Moyal representation of the vibronic density matrix with the ab initio multi state molecular dynamics in the ground and excited electronic states including the nonadiabatic couplings calculated "on the fly" at low computational demand. This method allows the simulation of femtosecond pump-probe and pump-dump signals based on an analytical formulation, which utilizes temperature dependent ground state initial conditions, an ensemble of trajectories carried out on the electronic excited state as well as on the ground state after the passage through the conical intersection in the case of nonadiabatic dynamics and for probing either in the cationic state or in the ground state. The choice of the systems we presented has been made in order to determine the timescales of the fast geometric relaxation leaving the bonding frame intact as during the dynamics in the first excited state of Na4F3, and of the bond breaking processes leading to conical intersection between the first excited state and the ground state as in Na3F2. The former is the smallest finite system prototype for an surface F-center of bulk color centers. The latter allows to study the photo isomerization in full complexity taking into account all degrees of freedom. In the case of Na4F3 after the fast geometric relaxation in the excited state leading to deformed cuboidal structure without breaking of bonds, different types of internal vibrational redistribution (IVR) processes have been identified in pump-dump signals by tuning the dump laser. In contrast, from the analysis of the pump-probe signals of Na3F2 cluster, the timescales for the metallic and the ionic bond breaking, as well as for the passage through conical intersection have been determined. Finally the conditions under which these processes can be experimentally observed have been identified.
Ultrafast ground state nuclear dynamics of small coinage metal clusters is theoretically explored in the framework of negative ion to neutral to positive ion (NeNePo) femtosecond pump−probe spectroscopy with the aim to determine the scope and perspective of this technique. This approach involves the preparation of an initial ensemble in the anionic ground state of the cluster, one-photon detachment by the pump pulse, the propagation of the system on the neutral electronic ground state, and detection via the cationic ground state by a time-delayed ionizing probe pulse. The calculations of the NeNePo-ZEKE signals under the condition of zero kinetic energy electrons are based on the combination of the Wigner distribution approach and ab initio molecular dynamics (MD) “on the fly” in the framework of gradient-corrected DFT for the propagation of an ensemble of classical trajectories and involves the average over the entire phase space. We have chosen examples of Ag2Au and Au4 to investigate time scales and the character of isomerization processes that are influenced by a local minimum corresponding to an energetically high-lying isomer with the structure related to the initial anionic structure. Capture of the nuclei within the local minimum takes place with dephased (Ag2Au) or nondephased (Au4) vibrational relaxation. Structural relaxations leading to isomerization processes are in both cases of delocalized nature and take place after 1 ps. In contrast, the Ag4 cluster represents an example for which isomerization processes do not occur, since rhombic structures with slightly different bond lengths are global minima of the anionic and neutral ground states. Therefore, the relaxation dynamics is characterized by regular oscillations, which serve as fingerprints of structural properties. On the basis of the analysis of pump−probe signals and underlying dynamics, this contribution provides information about conditions under which structural properties of gas-phase clusters (global and local minima) and isomerization processes can be observed in the framework of the NeNePo-ZEKE type of spectroscopy. The latter is important in the context of applicability of this technique to the investigation of cluster reactivity.
Objectives: Stratification of oncology drug therapy by genetic marker diagnostics can reveal additional patient benefit but also might influence the development process of drug manufacturers. The objective of this study is to identify and describe the most important incentives for pharmaceutical companies to develop personalized medicine drugs.
Methods: To describe the main factors influencing the decision making process in the development of personalized medicine drugs we designed a qualitative systemdynamic model. The main factors influencing the process and their priority ranking were determined by systematic literature search, structured expert interviews with pharmaceutical companies, test manufacturers and other key stakeholders such as regulatory bodies, reimbursement decision makers and payers. The model was build with the Consideo iModeler software package.
Results: In contrast to small companies big international companies constantly look for suitable companion diagnostic tests to select subgroups of high responder. The most important key factor for market success is the extent of clinical efficacy in comparison with competitors respectively the current treatment standard. Stratification of patient populations according to treatment response or frequency of adverse events using biomarker is regarded to increase clinical efficacy of the target indication. The test performance is important due to unsolved safety issues although not regarded as crucial for the success of the drug. In contrast to other stakeholders pharmaceutical companies did not consider personalized medicine to relevantly decrease development costs or marketing efforts respectively to increase the price potential for new drugs. A low prevalence of the remaining patient population after testing is not irrelevant but it is not seen as a factor which might lead to a stop of the development of a new drug by pharmaceutical companies.
Conclusions: Genetic stratification is seen as a breakthrough in cancer therapy by pharmaceutical companies and physicians. Due to the current need for improvement of approval and reimbursement processes for personalized medicine approaches in oncology especially in Europe future sales are more difficult to predict.
Arzneimittelversorgung
(2013)
Web portals and many Internet solutions contain objects with a geographical reference such as the position of a company or a tourist attraction. Existing maps are protected by copyright. The licence fee is high and it is very expensive and complicated to create own maps. Freely useable and suitable maps for presentations, such as open source, do not exist – although the project OpenGeoDB is growing day after day. Recently, however some changes occurred. After a registration, Yahoo and Google offer interfaces to their map data for non-commercial users. This can be used for free. The interfaces offer advanced user possibilities for accessing maps, which are mostly high resolution ones, using the Web 2 methods. We show how to integrate Google´s API interface into one's own web applications and finally, how regional data, stored in a database, can be presented by this solution. Currently, Google does not have sufficiently detailed maps for Eastern Europe yet. Nevertheless, our web solution uses data of the region Zips (Špis) in Slovakia. It demonstrates how geo-based data can be used for supporting regional marketing concepts by Web 2 in the future.
Portals are called web sites which are designed to offer services and/or an outline of special subjects. They have been developed as fast as information data bases and electronic communication facilities were extended. Recently, portals with geographically referenced information became important and popular for different fields like geo information systems of cities (see e. or the presentation of economically relevant data in the context of regional marketing, foreign direct investment or tourism by indicating important objects like public institutions, companies, hotels, sights, etc. on maps. In this manner they may contribute to the improvement of industrial structure and the marketing of a region. For representing geographical data on maps, applications with special client-server-architecture have to be developed. There are different solutions for the Internet using HTML and JavaScript, Flash or Java Applets. In our contribution we discuss currently available solutions and show an alternative approach. Our solution is based on the Java Applet technology and Asynchronous JavaScript and XML (Ajax). This technology is part of the web solutions known as Web 2.0 which is strongly discussed and developed in the present. Our results are demonstrated as a user-friendly web application with data of the Slovakian region Špis (Zips). An extended version of this web solution could be nicely incorporated into a modern concept for tourism of the Špis region.
In the last decade, portals on the WWW have been extensively developed for different applications in e-business, e-commerce, e-government or science and are used as an information and communication base. Recently, due to the progression of web- technologies, new user-friendly features could be added into portals. Among them the incorporation of geographic informations became most important since many relevant data are related to space. In such a way the value and the appropriate visualization of the relevant information as well as the ability to investigate the interrelation between different data could be reached (Bernhardt, 02). Geo-based web portals combine the features of common portals like searching for keywords or navigating with geo information systems (GIS). For a certain target group they provide a unique presentation of all relevant information within a region or a market, and provide user specific communication tools. In this context, providing maps is one of the main characteristics of geo-based web portals. Creating a geo-referenced map is a challenging and complex task since all relevant geo data like streets, objects, information of the landscape etc. have to be known and incorporated into the GIS. Therefore, a geo-object in the geo-based web portal has to contain both the geo-data and the content related data. Geo-data describe the structure of an object in space whereas the content related data provide additional attributes associated with the properties of the object (Dickmann & Zehner 2001). From the point of the architecture, a web-based map application consists of two essential components - the server and the client part. Typically, the server component is responsible for providing geographical information according to the client's request and returns the data and images suitable for the visualization back to the client application. The client component provides the user with a graphical user interface (GUI). Its main tasks are collecting the user input data and communicating with the server in order to retrieve the information as well as to provide interactive mechanisms for representing analyzing the results. The communication between the client and the sever component via a HTTP port is based on a defined request-response protocol. Typical solutions are implemented using JavaScript, Java applets or Flash and are discussed in more detail in the next section. In this contribution we describe an alternative approach using the Java Applet Technology, Asynchronous JavaScript and XML (Ajax). It's application for offering informations of companies operating in the field of food technology and food industry is shown. In such a way it represents a realization of our recently developed concept of a geo-based web portal (Hartmann et al, 05).
The internet is an unlimited growing and most comfortable information and communication base. In this context, web portals on the internet play an important role created for combining communication facilities and information data bases. An increasing number of portals involve web-based map applications to integrate geographic information for the representation of economical and other records. Web-based map applications are typically designed in a client-server architecture. Different solutions exist using especially HTML and JavaScript, Flash or Java applets. We discuss these possibilities and point out an alternative solution. Particularly, we show how to use Java Applet Technology and Asynchronous JavaScript and XML (Ajax) in this field. Finally, we report about our results as a complete, flexible map service solution which is available on the internet. An adapted kind of solution will be used by a geo-based marketing portal for offering information about the economic situation, social and cultural aspects and natural facts of regions to support joint-ventures inside the European Union.
Traditional Instrumentality x Value (I x V) models have attributed gains in performance groups to various conditions affecting the instrumentality of group members' effort for a variety of valued outcomes. Social identity models have challenged this interpretation, suggesting that the instrumentality of effort may be irrelevant when group identification is high. A laboratory study is reported in which both indispensability and group identification are manipulated, and participants' effort on a physical persistence task is assessed. Contrary to the social identity predictions but consistent with I x V predictions, the indispensability of effort had a positive effect on participants' effort. Group identification had no direct or moderating effects on effort. © 2008 Elsevier Inc. All rights reserved.
Counterproductive behaviors in teams: detrimental effects of cognitive loafing on transactive memory
(2013)
Cognitive interdependence in teams requires members to contribute their share to a common task. Cognitive loafing(reduced cognitive effort) can disrupt knowledge exchange in transactive memory systems. We administered a cognitive loafing measure to investigate its effects. Results show that cognitive loafing has significant negative impact on transactive memory, whereas affective commitment has a positive impact on transactive memory. Furthermore, we found that cognitive loafing within a team was not contagious among team members.
In a first study, we explored whether cognitive loafing (reduced cognitive effort) can disrupt knowledge exchange in transactive memory systems and administered a cognitive loafing measure to investigate its effects. In our second study, we explored if affective commitment and perceived team performance could counteract the detrimental effects of cognitive loafing. Results show that both affective commitment and perceived team performance moderated the relationship between observed cognitive loafing and transactive memory.
Applying the framework of ecological rationality, the authors studied the adaptivity of group decision making. In detail, they investigated whether groups apply decision strategies conditional on their composition in terms of task-relevant features. The authors focused on the recognition heuristic, so the task-relevant features were the validity of the group members' recognition and knowledge, which influenced the potential performance of group strategies. Forty-three three-member groups performed an inference task in which they had to infer which of two German companies had the higher market capitalization. Results based on the choice data support the hypothesis that groups adaptively apply the strategy that leads to the highest theoretically achievable performance. Time constraints had no effect on strategy use but did have an effect on the proportions of different types of arguments. Possible mechanisms underlying the adaptive use of recognition in group decision making are discussed.
Zulassung und Erstattung personalisierter Arzneimittel: Zwischenbilanz des Anpassungsprozesses
(2013)
Die Arzneimittelzulassung und der Aufnahmeprozess zur Kostenerstattung sollen die Entwicklung und Vermarktung von pharmazeutischen Innovationen mit Patientennutzen nicht behindern, zugleich aber die Wirtschaftlichkeit der Arzneimittelversorgung für die Kostenträger nicht gefährden. Eine Anpassung der Verfahren an die Merkmale personalisierter Arzneimittel erscheint notwendig. Dabei ist allerdings zu fragen, ob eine ungerechtfertigte Privilegierung erfolgt. In den USA und in der EU werden die jeweiligen Zulassungsverfahren für Arzneimittel und Tests schrittweise angepasst und integriert. Zulassung und Erstattungsentscheidungen sollen koordiniert werden. Eine Privilegierung, wie bei Arzneimitteln für seltene Indikationen (Orphan Drugs), findet jedoch für personalisierte Medizin nicht statt. Es bestehen keine unzumutbaren Hürden für die Hersteller. Zurückhaltung bei der Entwicklung innovativer Produkte wäre deshalb nicht gerechtfertigt.
Age discrimination is a common problem in organizations. In our pilot study, we want to explore the processes how the desired retirement age is influenced by age discrimination and see psychological empowerment as an important mediator for the relationship between these variables. Data stem from an online questionnaire completed by 130 employees from different organizations in Germany (all 50 years or older). Our results show that age discrimination is an antecedent for the desired retirement age. It has a direct as well as an indirect (via psychological empowerment) effect on the desired retirement age.
Im Projektgeschäft geht die Bedeutung des Vertrages weit über die Herstellung von Rechtsbeständigkeit hinaus. Daraus ergeben sich Konsequenzen für die inhaltliche Ausgestaltung des Vertrages, die von einem der Autoren in dieser Zeitschrift bereits erörtert wurden. Aber auch die äußere Darbietung des Vertrages leistet einen wesentlichen, in aller Regel unterschätzten Beitrag zu seiner Umsetzung. Im Folgenden wird gezeigt, wie sich sprachliche Fassung und Visualisierung des Vertrages auf seine Handhabung auswirken und welche Darbietungsmerkmale seine Akzeptanz durch nichtjuristische Nutzer erhöhen können.
Change in teams
(2011)
Humor ist Bestandteil tagtäglicher sozialer Interaktion und ein relevantes Forschungsthema - betrachtet man seinen Einfluss auf Einstellungen und Verhalten (Martin, 2007; Rissland, 2002). Schwierige oder unbequeme Ideen können sozial angemessen geäußert werden, wenn sie humorvoll verpackt sind, desgleichen hilft Humor bei der Kontrolle zwischenmenschlicher Interaktionen und kann emotional unterstützen. Humor ist ein komplexes Phänomen mit diversen Auswirkungen, abhängig von Inhalt und Kontext. Während Humor im Lehr-/Lernkontext schon länger Beachtung findet (z.B. Bryant et al., 1980), wird dieser in der arbeits- und organisationspsychologischen Forschung erst in letzter Zeit entdeckt (Romero & Cruthirds, 2006; Wood, Beckmann & Rossiter, 2011). Dabei hat Humor vielfältige Einflüsse auf Lernen (Ziv, 1988) sowie Leistung, Zufriedenheit, Kohäsion, Gesundheit, Burnout und Stress (Metaanalyse, Glew et al., 2010). Auch die negativen Aspekte von Humor finden zunehmend Beachtung (Martin et al., 2003). In dieser Arbeitsgruppe betrachten wir Humor aus pädagogischer und arbeits-/organisationspsychologischer Perspektive. Dabei kommen verschiedene Formen des Humors (Sinn, Stile) in diversen Alterklassen zur Anwendung, um Zusammenhänge mit Lernen und Motivation, Kreativität, Fehlerklima, Führung und Innovation sowie Verhalten in Verhandlungen zu zeigen. In dieser Arbeitsgruppe präsentieren wir folgende spannende Ergebnisse: Schüler lernen besser und sind motivierter, wenn Lehrer Humor anwenden (Bieg & Dresel). Die positiven (sozialer und selbstaufwertender) Humorstile sowie die negativen (aggressiver und selbsabwertender) hängen mit Fehlerorientierung (Csonka & Scheel) sowie mit Kreativität (Scheel & Csonka) zusammen. Humorvolle Führung ist mit innovativem Verhalten verbunden (Pundt) und humorvolle Kommentare in Verhandlungen wirken sich auf den Verhandlungsverlauf aus (Brantl, Gockel & Gibson). Wir plädieren für mehr ernsthafte Humorforschung, insbesondere zu dessen Schatten- und Sonnenseiten. Diskutantin: Frau Prof. Dr. Gisela Mohr, Universität Leipzig.
Durch Partizipation können Individuen und Gruppen ihre Interessen in Organisationen sicherstellen und selbstbestimmt handeln (Wilpert, 1989). Partizipation kann sich auf verschiedene Arten von Entscheidungen und auf verschiedene Ebenen der Organisation beziehen. Sie bedeutet generell, dass mehr als eine Person Entscheidungen vorbereitet oder fällt (Wegge et al., 2010). In dieser Arbeitsgruppe betrachten wir in drei Beiträgen Partizipation auf Teamebene (am Beispiel von geteilter und verteilter Führung), und in zwei weiteren Beiträgen Partizipation auf Organisationsebene. Dabei wird es um die Messung, Prädiktoren und Auswirkungen von Partizipation gehen, um dem komplexen und vielschichtigen Phänomen und seiner Wichtigkeit gerecht zu werden. Piecha und Wegge präsentieren eine Kurzskala zur Messung konstruktiver und destruktiver geteilter Führung in Teams und zeigen in einer Fragebogenstudie mit Altenpflegern differenzierte Zusammenhänge mit Gesundheit auf. Garbers und Konradt zeigen in ihrer Studie zwei positive Konsequenzen verteilter Führung am Beispiel von Apothekenteams: bessere Teamleistung und erhöhtes affektives Commitment. Gockel und Schmidt beschäftigen sich mit den Prädiktoren individuellen Führungsverhaltens in Teams und präsentieren, inwiefern sich eigene Persönlichkeitseigenschaften und die Eigenschaften der Teamkollegen auf Führungsverhalten auswirken. Mende und Wegge untersuchten in einem Experiment Erleben und Verhalten in partizipationsrelevanten Situationen in Organisationen. Pircher-Verdorfer und Kollegen stellen schließlich die psychometrischen Eigenschaften und Korrelate eines englischsprachigen Fragebogens zu sozial-moralischem Klima in Organisationen vor. Als Diskutant haben wir Jörg Felfe, Helmut-Schmidt-Universität Hamburg, eingeladen.
In a lab study, the effects of metacognition and perspective taking on the development of a transactive memory were examined. Discussions of 20 groups were coded with a specifically developed coding scheme. Perspective taking showed the expected positive effect, but metacognition did not. The features of the metacognition training might explain this.
Mock juries were exposed to an argument for nullifying the law to achieve a just verdict, an argument that the law must be obeyed, to both or neither argument. Both final verdicts and social-influence showed that either argument alone increased the power of pro-conviction factions, but that these effects were weakened when both arguments were heared.