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A common wisdom in quantum mechanics is that the Hamiltonian has to be Hermitian in order to ensure a real eigenvalue spectrum. Yet, parity–time (PT)-symmetric Hamiltonians are sufficient for real eigenvalues and therefore constitute a complex extension of quantum mechanics beyond the constraints of Hermiticity. However, as only single-particle or classical wave physics has been exploited so far, an experimental demonstration of the true quantum nature of PT symmetry has been elusive. In our work, we demonstrate two-particle quantum interference in a PT-symmetric system. We employ integrated photonic waveguides to reveal that the quantum dynamics of indistinguishable photons shows strongly counterintuitive features. To substantiate our experimental data, we analytically solve the quantum master equation using Lie algebra methods. The ideas and results presented here pave the way for non-local PT-symmetric quantum mechanics as a novel building block for future quantum devices.

Plants naturally cycle amino acids across root cell plasma membranes, and any net efflux is termed exudation. The dominant ecological view is that microorganisms and roots passively compete for amino acids in the soil solution, yet the innate capacity of roots to recover amino acids present in ecologically relevant concentrations is unknown. We find that, in the absence of culturable microorganisms, the influx rates of 16 amino acids (each supplied at 2.5 micromolar) exceed efflux rates by 5% to 545% in roots of alfalfa (Medicago sativa), Medicago truncatula, maize (Zea mays), and wheat (Triticum aestivum). Several microbial products, which are produced by common soil microorganisms such as Pseudomonas bacteria and Fusarium fungi, significantly enhanced the net efflux (i.e. exudation) of amino acids from roots of these four plant species. In alfalfa, treating roots with 200 micromolar phenazine, 2,4-diacetylphloroglucinol, or zearalenone increased total net efflux of 16 amino acids 200% to 2,600% in 3 h. Data from 15N tests suggest that 2,4-diacetylphloroglucinol blocks amino acid uptake, whereas zearalenone enhances efflux. Thus, amino acid exudation under normal conditions is a phenomenon that probably reflects both active manipulation and passive uptake by microorganisms, as well as diffusion and adsorption to soil, all of which help overcome the innate capacity of plant roots to reabsorb amino acids. The importance of identifying potential enhancers of root exudation lies in understanding that such compounds may represent regulatory linkages between the larger soil food web and the internal carbon metabolism of the plant.

Current project development practices often fail to engage stakeholders early and effectively. Decision support is often non-inclusive, single-sided, and lacking in transparency, while complexity goes beyond human's comprehension. Additionally, many approaches focus primarily on technical system aspects, neglecting the integration of stakeholders' individual preferences. This often results in project impasses, leaving stakeholders unable to collaboratively achieve a \"yes.\" There is a need for a purely associative, a-priori design approach that integrates system realities and stakeholder ideals within a joint socio-technical solution space. The state-of-the-art Preferendus, embedded in the proven Open Design Systems (Odesys) methodology, is a neutral tool for transforming complexity into success. Aiming for synthesis, Odesys' robust IMAP optimization method generates a single best-fit design solution. Here, Odesys is applied for a Dutch wind farm stalemate development, balancing multiple stakeholder preferences, wind farm performances, and project constraints. The success of this approach hinges on stakeholder trust and input. This article introduces a structured stakeholder assessment method using choice-based conjunctive analysis (CBCA), facilitating transparent determination of global and local stakeholder weights and preference functions. Modelling 'disputable' exogenous factors as endogenous design parameters, the application demonstrates how one can shift toward a collaborative \"yes.\" For this, it is concluded that a zoomed-out solution space would enable the energy transition to be tackled with multiple options rather than a prescribed one. The Odesys approach fosters decision-making that aligns with the social threefold principles of freedom, equality, and fraternity, guiding projects toward genuine democratic outcomes rather than selecting from curated options.

The Primate Station on Tenerife in the Canary Islands is known for Wolfgang Köhler's experiments (1914-20) on the intelligent behavior of anthropoid apes. The Station was founded in 1912 by Max Rothmann, neurophysiologist at the University of Berlin, and sponsored by the Royal Prussian Academy of Sciences. The present article describes the circumstances and sudden appointment of Eugen Teuber as director. In addition to setting up the Station in 1913, Teuber observed the \"affective calls\" of chimpanzees; their \"gestural language\" led him to conclude that one might communicate with them by means of gestural signs like those used by deaf-mutes. His findings are compared with discoveries made 50 years later. Photographs taken by Teuber illustrate his tenure. He left a well-functioning Station to Wolfgang Köhler whose first intelligence experiment of December 31, 1913, he recorded.

Strategic project planning and dynamic control are essential to ensure that complex projects are both prepared and executed best-fit-for-common-purpose, guided by three interrelated strategies: (1) Agreeing First, (2) Acting Feasibly, and (3) Adapting Flexibly. When these strategies become too complex for humans to fully conceive and manage, effective computer-aided decision support becomes crucial. However, standard simulation-driven evaluation and a-posteriori decision-making are typically single-sided and technically focused focus, rather than applying a combined simulation-and-optimisation approach that a-priori integrates stakeholder interests and their mitigation behavior. Moreover, current planning and control methodologies often lack robust stochastic representations and associative multi objective optimisation methods that capture the full socio-technical complexity while maximizing the potential within reach. This paper introduces Odycon (Open Design and Dynamic Control), a new purpose-driven project management methodology that provides an actionable solution to these challenges. It presents a generic mathematical framework for project planning and control that integrates stakeholder preferences (human domain) with system performances (physical domain), enabling more effective planning and dynamic control. Odycon integrates standard Monte Carlo simulation (MCS) with the novel Integrative Maximisation of Aggregated Preferences (IMAP) optimisation method to develop a best-fit strategic plan and the most effective mitigation control strategies. Its value is demonstrated through applications in offshore wind installation and highway infrastructure projects, showcasing advances in associative design and decision-making, and aiming for a best-fit-for-common-purpose synthesis across different complex project phases.

Strategic project planning and dynamic control is essential for ensuring complex projects to be executed best-fit for common purpose. When best-for-project strategies are no longer conceivable for humans, there is a need for effective and efficient computer-aided decision support. To this end, standard simulation-driven evaluation and a-posteriori decision-making is often used instead of a combined simulation and optimisation approach that a-priori integrates the stakeholders goal orientation and risk management into a best-fit design solution. However, recently developed state-of-the-art planning and control methodologies that do already incorporate this integration still lack a stochastic representation and/or an associative multi-objective approach. This paper presents a new project management methodology, called Odycon (Open design and dynamic control), which dissolves the aforementioned shortcomings. To enable this, a generic mathematical statement is first formulated for project planning and dynamic control uniting technical logistical) capabilities, human goal-oriented behaviour, and stakeholders interests. Then, both Monte-Carlo simulation (MCS) and the Integrative Maximisation of Aggregated Preferences (IMAP) optimisation method are combined, resulting in a best-fit strategic planning and dynamic control methodology. Odycons use and added value are demonstrated for two applications: (1) a pure strategic planning of an offshore wind installation project, and (2) a pure dynamic control of a highway infrastructure construction project. Both applications demonstrate Odycons advances in concurrent and associative design and decision-making, offering best-fit for common purpose synthesis for different complex project phases.

Semiconductor microcavities with artificial single-photon emitters have become one of the backbones of semiconductor quantum optics. In many cases however, technical and physical issues limit the study of optical fields to incoherently excited systems. We analyze the model of a two-level system in a single-mode cavity, where the former is incoherently driven. The specific structure of the applied master equation yields a recurrence relation for the steady-state values of correlations of the intracavity field and the emitter. We provide boundary conditions, that permit a systematical, easy to implement solution, which is numerically less demanding than standard methods. Different cavity systems from previous experiments are analyzed. The derived boundary conditions also allow us direct analytical statements about the overall quantum state and its higher order moments. With this we can give very good approximations for the full quantum state of the field and show, that for every physically reasonable set of system parameters, the state of the intracavity field is nonclassical.