The Environmental Effects of Global Changes on Northeast Central Europe in the Case of Non-Modified Agricultural Management

Climate impact scenarios for agriculture usually consider yield development, landscape water balance, nutrient dynamics or the endangerment of habitats separately. Scenario results are further limited by roughly discriminated land use types at low spatial resolution or they are restricted to single sites and isolated crops. Here, we exemplify a well data based comprehensive sensitivity analysis of a drought endangered agrarian region in Northeast Germany using a 2050 climate scenario. Coherently modelled results on water balance and yields indicate that agricultural production may persist, whereas wetlands and groundwater production will be negatively affected. The average percolation rate decreases from 143 mm a-1 to 12 mm a-1, and the average yield decline broken down by crops ranges from 4% for summer wheat to 14% for potatoes (main cereals: 5%)

Climate bifurcations in a Schwarzschild equation model of the Arctic atmosphere

A column model of the Arctic atmosphere is developed including the nonlinear positive feedback responses of surface albedo and water vapour to temperature. The atmosphere is treated as a grey gas and the flux of longwave radiation is governed by the two-stream Schwarzschild equations. Water vapour concentration is determined by the Clausius–Clapeyron equation. Representative concentration pathways (RCPs) are used to model carbon dioxide concentrations into the future. The resulting 9D two-point boundary value problem is solved under various RCPs and the solutions analysed. The model predicts that under the highest carbon pathway, the Arctic climate will undergo an irreversible bifurcation to a warm steady state, which would correspond to annually ice-free conditions. Under the lowest carbon pathway, corresponding to very aggressive carbon emission reductions, the model exhibits only a mild increase in Arctic temperatures. Under the two intermediate carbon pathways, temperatures increase more substantially, and the system enters a region of bistability where external perturbations could possibly cause an irreversible switch to a warm, ice-free state.</p

Understanding extracellular vesicle and nanoparticle heterogeneity: novel methods and considerations

Extracellular vesicles (EVs) are a heterogeneous population of membrane-enclosed nanoparticles released by cells. They play a role in intercellular communication and are involved in numerous physiological and pathological processes. Cells release subpopulations of EVs with distinct composition and inherent biological function which overlap in size. Current size-based isolation methods are, therefore, not optimal to discriminate between functional EV subpopulations. In addition, EVs overlap in size with several other biological nanoparticles, such as lipoproteins and viruses. Proteomic analysis has allowed for more detailed study of EV composition, and EV isolation approaches based on this could provide a promising alternative for purification based on size. Elucidating EV heterogeneity and the characteristics and role of EV subpopulations will advance our understanding of EV biology and the role of EVs in health and disease. Here, we discuss current knowledge of EV composition, EV heterogeneity and advances in affinity based EV isolation tools

A Comparison of Production and Soils in Modified Mixed Prairie Community

This study examined the effects of reseeding a Stipa-Agropyron- Bouteloua community to monocultures of crested wheatgrass (Agropyron cristatum (L.) Geartn.), Russian wild rye grass (Elymus junceus Fisch.), and wheat (Triticum aestivum L.) on above and below ground biomass and indicators of soil quality. Summer fallowed wheat produced 10817 kg ha-1 and 4090 kg ha-1 of above ground below ground biomass respectively whereas the native community produced 3191 kg ha-1 above ground and 13013 kg ha-1 of below ground biomass. However wheat, crested wheatgrass and Russian wildrye grass generally showed a lower biological index, phosphatase and dehydrogenase activity

An energy balance model for paleoclimate transitions

A new energy balance model (EBM) is presented and is used to study paleoclimate transitions. While most previous EBMs only dealt with the globally averaged climate, this new EBM has three variants: Arctic, Antarctic and tropical climates. The EBM incorporates the greenhouse warming effects of both carbon dioxide and water vapour, and also includes ice–albedo feedback and evapotranspiration. The main conclusion to be inferred from this EBM is that the climate system may possess multiple equilibrium states, both warm and frozen, which coexist mathematically. While the actual climate can exist in only one of these states at any given time, the EBM suggests that climate can undergo transitions between the states via mathematical saddle-node bifurcations. This paper proposes that such bifurcations have actually occurred in Paleoclimate transitions. The EBM is applied to the study of the Pliocene paradox, the glaciation of Antarctica and the so-called warm, equable climate problem of both the mid-Cretaceous Period and the Eocene Epoch. In all cases, the EBM is in qualitative agreement with the geological record.</p

Soliton compression and supercontinuum spectra in nonlinear diamond photonics

We numerically explore synthetic crystal diamond for realizing novel light sources in ranges which are up to now difficult to achieve with other materials, such as sub-10-fs pulse durations and challenging spectral ranges. We assess the performance of on-chip diamond waveguides for controlling light generation by means of nonlinear soliton dynamics. Tailoring the cross-section of such diamond waveguides allows to design dispersion profiles with custom zero-dispersion points and anomalous dispersion ranges exceeding an octave. Various propagation dynamics, including supercontinuum generation by soliton fission, can be realized in diamond photonics. In stark contrast to usual silica-based optical fibers, where such processes occur on the scale of meters, in diamond millimeter-scale propagation distances are sufficient. Unperturbed soliton-dynamics prior to soliton fission allow to identify a pulse self-compression scenario that promises record-breaking compression factors on chip-size propagation lengths

Применение информационных технологий и этические нюансы в управлении массовым сознанием

This paper discusses the current value of information technology in our lives, as well as their application to control the mass consciousness

Minimal state models for ionic channels involved in glucagon secretion

Pancreatic alpha cells synthesize and release glucagon. This hormone along with insulin, preserves blood glucose levels within a physiological range. During low glucose levels, alpha cells exhibit electrical activity related to glucagon secretion. In this paper, we introduce minimal state models for those ionic channels involved in this electrical activity in mice alpha cells. For estimation of model parameters, we use Monte Carlo algorithms to fit steadystate channel currents. Then, we simulate dynamic ionic currents following experimental protocols. Our aims are 1) To understand the individual ionic channel functioning and modulation that could affect glucagon secretion, and 2) To simulate ionic currents actually measured in voltage-clamp alpha-cell experiments in mice. Our estimations indicate that alpha cells are highly permeable to sodium and potassium which mainly manage action potentials. We have also found that our estimated N-type calcium channel population and density in alpha cells is in good agreement to those reported for L-type calcium channels in beta cells. This finding is strongly relevant since both, L-type and N-type calcium channels, play a main role in insulin and glucagon secretion, respectively

Evaluation of job satisfaction of practice staff and general practitioners: an exploratory study

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