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The main qualitative properties of the solution set of almost lower (upper) semicontinuous one-sided Perron differential inclusion with state constraints in finite dimensional spaces are studied. Using the technique introduced by Veliov (Nonlinear Anal 23:1027–1038, 1994) we give sufficient conditions for the solution map of the above state constrained differential inclusion to be continuous in the sense of Hausdorff metric. An application on the propagation of the continuity of the state constrained minimum time function associated with the nonautonomous differential inclusion and the target zero is given. Some relaxation theorems are proved, which are used afterward to derive necessary and sufficient conditions for invariance.  相似文献   
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Three different types of experiments have been performed to explore the complete and incomplete fusion dynamics in heavy-ion collisions. In this respect, first experiment for the measurement of excitation functions of the evaporation residues produced in the 20Ne + 165Ho system at projectile energy ranges ≈2–8 MeV /nucleon has been done. Measured cumulative and direct cross-sections have been compared with the theoretical model code PACE-2, which takes into account only the complete fusion process. It has been observed that, incomplete fusion fraction is sensitively dependent on projectile energy and mass asymmetry between the projectile and the target systems. Second experiment for measuring the forward recoil range distributions of the evaporation residues produced in the 20Ne + 165Ho system at projectile energy ≈8 MeV /nucleon has been done. It has been observed that, some evaporation residues have shown additional peaks in the measured forwardrecoil range distributions at cumulative thicknesses relatively smaller than the expected range of the residues produced via complete fusion. The results indicate the occurrence of incomplete fusion involving the breakup of 20Ne into 4He + 16O and /or 8Be + 12C followed by one of the fragments with target nucleus 165Ho. Third experiment for the measurement of spin distribution of the evaporation residues produced in the 16O + 124Sn system at projectile energy ≈6 MeV /nucleon, showed that the residues produced as incomplete fusion products associated with fast α and 2 α-emission channels observed in the forward cone, are found to be distinctly different from those of the residues produced as complete fusion products. The spin distribution of the evaporation residues also inferred that in incomplete fusion reaction channels input angular momentum (J 0) increases with fusion incompleteness when compared to complete fusion reaction channels. Present observation clearly shows that the production of fast forward α-particles arises from relatively larger angular momentum in the entrance channel leading to peripheral collision.  相似文献   
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ABSTRACT. The use of marine protected areas (MPAs) as a basic management tool to limit exploitation rates in marine fisheries has been widely suggested. Models are important in predicting the consequences of management decisions and the design of monitoring programs in terms of policy goals. However, few tools are available that consider both multiple fleets and ecosystem scale dynamics. We use a new applied game theory tool, Ecoseed, that operates within a temporally and spatially explicit biomass dynamics model, Ecopath with Ecosim, to evaluate the efficacy of marine protected areas in the North Sea in both ecological and economic terms. The Ecoseed model builds MPAs based on the change in values of predicted economic rents of fisheries and the existence value of biomass pools in the ecosystem. We consider the market values of four fisheries operating in the North Sea: a trawl fishery, a gill net fishery, a seine fishery, and an industrial (reduction) fishery. We apply existence values, scaled such that their aggregate is similar to the total fishery value, to six biomass pools of concern: juvenile cod, haddock, whiting, saithe, seals, and the collective pool ‘Other predators’ that include marine mammals. Four policy options were considered: to maximize the rent only; to maximize the existence values only; to maximize the sum of the rent and existence values; and, finally, to maximize the sum of the rent and the existence values, but excluding only the trawl fleet from the MPA. The Ecoseed model suggests that policy goals that do not include ecological considerations can negatively impact the rents obtained by the different fishing sectors. The existence values will also be negatively impacted unless the MPA is very large. The Ecoseed model also suggests that policy goals based solely on existence values will negatively impact most fisheries. Under policy options that included ecological considerations, maximum benefits were derived from an MPA that covered 25–40% of the North Sea, placed along the southern and eastern coasts. Finally, the Ecoseed model suggests that an exclusion of the trawl fishery only from the MPA can provide small‐to‐substantial positive impacts to most species and fleets; this relative impact depends on level of interaction between the trawl fleet and the other fleets target species (e.g., through bycatch).  相似文献   
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ABSTRACT. What bio‐economic benefits can be expected from the implementation of marine protected areas (MPAs) in a fishery facing a shock in the form of recruitment failure, and managed jointly compared to separately? What are the optimal sizes of MPAs under cooperation and non‐cooperation? I explore these questions in the current paper by developing a computational two‐agent model, which incorporates MPAs using the North East Atlantic codfishery as an example. Results from the study indicate that MPAs can protect the discounted economic rent from the fishery if the habitat is likely to face a shock, andfishers have a high discount rate. The total standing biomass increases with increasing MPA size but only up to a point. Basedon the specifics of the model, the study also shows that the economically optimal size of MPA for cod varies between 50 70% depending on (i) the exchange rate between the protectedandunprotectedareas of the habitat; (ii) whether fishers behalf cooperatively or non‐cooperatively; and(iii) the severity of the shock that the ecosystem may face.  相似文献   
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Cell arrays are of foremost importance for many applications in pharmaceutical research or fundamental biology. Although arraying techniques have been widely investigated for adherent cells, organization of cells in suspension has been rarely considered. The arraying of non-adherent cells using the diamagnetic repulsive force is presented. A planar arrangement of Jurkat cells is achieved at the microscale above high quality microfabricated permanent magnets with remanent magnetization of J(r)≈ 1 T, in the presence of a paramagnetic contrast agent. The cytotoxicity of three Gd based contrast agents, Gd-DOTA, Gd-BOPTA and Gd-HP-DO3A, is studied. Among them, Gd-HP-DO3A appears to be the most biocompatible toward Jurkat cells. In close agreement with analytical simulations, diamagnetically 'suspended' cells have been successfully arrayed above square and honeycomb-like micromagnet arrays, which act as a "diamagnetophobic" surface. Living cell trapping is achieved in a simple manner using concentrations of Gd-HP-DO3A as low as 1.5 mM.  相似文献   
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ABSTRACT

Nanotechnology is an emerging field of science. The base of nanotechnology is nanoparticles. The size of nanoparticles ranges from 1 to 100?nm. The nanoparticles are classified into different classes such as inorganic nanoparticles, organic nanoparticles, ceramic nanoparticles and carbon base nanoparticles. The inorganic nanoparticles are further classified into metal nanoparticles and metal oxide nanoparticles.similarly carbon base nanoparticles classified into Fullerene, Carbon nanotubes, Graphene, Carbon nanofiber and carbon black Nanoparticles are also classified on the basis of dimension such as one dimension nanoparticles, two-dimension nanoparticles and three-dimension nanoparticles. The nanoparticles are synthesized by using two approaches like top-down approach and bottom-up approach. In this review chemical, physical and green synthesis of nanoparticles is reported. The synthesized nanoparticles are synthesized using different qualitative and quantitative techniques. The Qualitative techniques include Fourier Transform Infrared Spectroscopy (FT-IR), UV-Vis spectrophotometry, Scanning electron microscope (SEM), X.ray diffraction (XRD) and Atomic Force Microscopy (AFM). The Quantitative techniques include Transmission Electron Microscopy (TEM), Annular Dark-Field Imaging (HAADF) and Intracranial pressure (ICP). The nanoparticles have different application which is reported in this review.  相似文献   
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Abstract. The dynamic deterrence model (DDM) represents an analytical framework widely used for analyzing compliance with fishery regulations aiming for sustainable fishery management. However, applications of the DDM have so far been limited to the case of constant probability of detection that assumes independence of the length of time to detection. This paper modifies the DDM to allow for more flexible and broader specification by introducing, for the first time, two important variables to the supply of offences function, namely evasion activity and enforcement efforts and accommodating inconstant probability of detection specifications. Determinants of probability of detection are specified and important potential extensions of the modified DDM are discussed in this paper. The relative magnitude of the effects of each of these determinants on probability of detection, however, remains an important empirical question that requires further investigation for prioritization of policy actions.  相似文献   
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Rasool  Nouman  Akhtar  Ammara  Hussain  Waqar 《Structural chemistry》2020,31(5):1777-1783
Structural Chemistry - At the end of December 2019, a novel strain of coronavirus, given the name of 2019-nCoV, emerged for exhibiting symptoms of severe acute respiratory syndrome. The virus is...  相似文献   
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