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The sharp decline in seminatural areas worldwide is undisputed, but the consequences of this decline, apart from the loss of biodiversity, cannot be fully assessed. To restore ecosystems or landscapes, it is essential to have so-called reference sites. We want to show how reliable reference sites can be found in heavily used landscapes with the help of independent sources, and we present an approach that can be used in other regions, because it is very well suited for developing essential databases in the context of theses at different levels. A forest of seminatural stocking was selected in northeast Germany as a case study. The mapping of archival sources and the analyses of historical maps as well as field investigations were combined to reconstruct the dynamics of vegetation and soil for the last several centuries to thousands of years. Palynological data from nearby sites show that the study area has been forested for several millennia and has been less influenced by humans in the last 450 years. Together with historical maps of tree species composition, it allows to infer that the specific forest has been preserved in good ecological conditions for at least 250 years. Soil inventory and field studies on two catenas and corings support this conclusion, as they rarely show signs of anthropogenic erosion and related colluviation. Using a multisource approach, it is possible to identify potential reference sites that provide a reliable basis for ecosystem or landscape restoration.

Mechanical systems facilitate the development of a hybrid quantum technology comprising electrical, optical, atomic and acoustic degrees of freedom.sup.1, and entanglement is essential to realize quantum-enabled devices. Continuous-variable entangled fields--known as Einstein-Podolsky-Rosen (EPR) states--are spatially separated two-mode squeezed states that can be used for quantum teleportation and quantum communication.sup.2. In the optical domain, EPR states are typically generated using nondegenerate optical amplifiers.sup.3, and at microwave frequencies Josephson circuits can serve as a nonlinear medium.sup.4-6. An outstanding goal is to deterministically generate and distribute entangled states with a mechanical oscillator, which requires a carefully arranged balance between excitation, cooling and dissipation in an ultralow noise environment. Here we observe stationary emission of path-entangled microwave radiation from a parametrically driven 30-micrometre-long silicon nanostring oscillator, squeezing the joint field operators of two thermal modes by 3.40 decibels below the vacuum level. The motion of this micromechanical system correlates up to 50 photons per second per hertz, giving rise to a quantum discord that is robust with respect to microwave noise.sup.7. Such generalized quantum correlations of separable states are important for quantum-enhanced detection.sup.8 and provide direct evidence of the non-classical nature of the mechanical oscillator without directly measuring its state.sup.9. This noninvasive measurement scheme allows to infer information about otherwise inaccessible objects, with potential implications for sensing, open-system dynamics and fundamental tests of quantum gravity. In the future, similar on-chip devices could be used to entangle subsystems on very different energy scales, such as microwave and optical photons. A parametrically driven 30-micrometre-long silicon nanostring oscillator emits stationary path-entangled microwave radiation, squeezing the joint field operators of two thermal modes by 3.4 decibels below the vacuum level., Author(s): S. Barzanjeh [sup.1] , E. S. Redchenko [sup.1] , M. Peruzzo [sup.1] , M. Wulf [sup.1] , D. P. Lewis [sup.1] , G. Arnold [sup.1] , J. M. Fink [...]

Research having to do with use of an unshunted comparator as a device for quantum measurements is decribed and discussed.

Electrical steel with a Si content up to 6.5 wt% is a good soft magnetic material, because the power losses are reduced through the increased electrical resistivity of the bulk material by the presence of alloying elements like Si and Al. Nevertheless, with the increasing of the alloying elements, the concentration of Fe atoms in the bulk is reduced and a lower magnetic saturation is reached, Samples are produced by hot dipping in a Si-Al hypereutectic bath, followed by annealing treatments for diffusion. Series of different concentration profiles have been obtained and the magnetic properties measured. A short immersion is sufficient to form a SiAl enriched layer with D[0.sub.3] ordered structure (25at% Si-Al) in the steel surface: 10 [micro]m of D[0.sub.3] or more can be obtained after 20 s immersion (dependent on substrate and experimental conditions). A short diffusion annealing lowers and broadens this level, e.g., to a classical level of 6.5 wt% of Si, while the center of the steel remains at the original level (e.g., 3 wt% Si). Similar gradients are obtained with the simultaneous presence of Si and Al. Magnetic measurements were performed at 50 and 400 Hz after different thermal cycles, leading to different gradients of Si and Al. The power losses are reduced more than 50% in the final material compared with the original. It appears that a short annealing after the dipping already gives low power losses, even before a homogeneous concentration profile is obtained over the sample thickness. A smooth concentration gradient is preferable, with a lower Si content in the center, in order to maintain a good magnetic saturation. This can also be shown through modeling of the magnetic behavior with the concentration gradient. The reduction of power losses is more pronounced at 400 Hz, proving the importance of the skin effect. A further advantage of this procedure is the shorter annealing time after hot dipping. Index Terms--Concentration gradient, electrical steel, magnetic properties, power losses, Si.

In this paper, a procedure which allows magnetic measurements in different directions with respect to the direction of the applied stress is described. Experimental data on a nonoriented electrical steel is presented. The magnetic properties in different directions were determined as a function of mechanical tensile stress. The impact of the residual effects of tensile stress on the magnetic properties of nonoriented electrical steel is considered. Index Terms--Magnetic measurements, residual effects.

The article focuses on the sodium leak channel (NALCN) is essential for survival in mammals. It mentions the resulting NALCN channel complex is constitutively active and conducts monovalent cations but is blocked by physiological concentrations of extracellular divalent cations; and also mentions that voltage-sensing domains can give rise to a broader range of gating phenotypes than previously anticipated.