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41.
Breakup cross sections were obtained for the 6Li + 144Sm system at energies above and below the Coulomb barrier from a detailed analysis of the data recorded at backward angles. These cross sections are compared with inelastic target excitations previously reported revealing a similar behavior as a function of the bombarding energy but a large absolute difference between them. Using kinematical considerations we have analyzed possible contributions from different breakup channels and we have extracted information on magnitudes such as the relative kinetic energies of the corresponding breakup fragments.  相似文献   
42.
A method for enhancing the signal to noise ratio (SNR) in NMR volume coils is described. By introducing inserts made of low-loss, high dielectric constant material into specific locations in the coil, the SNR can often be enhanced by up to 20%, while B1 homogeneity is hardly affected. A model for predicting the limit of the SNR improvement is also presented. The model accurately predicts the SNR gain obtained in both numerical simulations and experiment. An experiment was conducted on a mini-MRI system. Experimental results are in very good agreement with the simulations in regard to both SNR improvement and B1 enhancement in transmission. Inserts made of ultra high dielectric constant materials can be as thin as few millimeters, thus, conveniently fitting into existing coil-sample gaps in volume coils.  相似文献   
43.
Hit-and-run algorithms are Monte Carlo methods for detecting necessary constraints in convex programming including semidefinite programming. The well known of these in semidefinite programming are semidefinite coordinate directions (SCD), semidefinite hypersphere directions (SHD) and semidefinite stand-and-hit (SSH) algorithms. SCD is considered to be the best on average and hence we use it for comparison.We develop two new hit-and-run algorithms in semidefinite programming that use diagonal directions. They are the uniform semidefinite diagonal directions (uniform SDD) and the original semidefinite diagonal directions (original SDD) algorithms. We analyze the costs and benefits of this change in comparison with SCD. We also show that both uniform SDD and original SDD generate points that are asymptotically uniform in the interior of the feasible region defined by the constraints.  相似文献   
44.
Fusion, breakup and scattering for the 9Be + 144Sm system at near barrier energies are investigated by different approaches. We show that at energies above the barrier there is a small complete fusion suppression when compared with predictions from a double folding potential and with a similar tightly bound system. At sub-barrier energies there is no significant deviation from the predictions using coupled channel calculations that do not include the breakup channel. The energy dependence of the optical potential does not show the usual threshold anomaly found in tightly bound systems. From a simultaneous analysis of fusion and scattering data we estimate the distance where breakup starts to occur.  相似文献   
45.
The equation , , is studied in and in the periodic case. It is shown that the equation is well-posed in and possesses regularizing properties. For nonnegative initial data and the solution decays in as . In the periodic case it tends uniformly to a limit. A consistent difference scheme is presented and proved to be stable and convergent.

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46.
A double superconducting solenoid system is installed at the Pelletron Laboratory of the University of S?o Paulo, Brazil. This system allows the production of secondary beams of 8Li, 6He, 7Be and others light exotic nuclei. The first results using this facility are presented.  相似文献   
47.
Journal of Radioanalytical and Nuclear Chemistry - Uranium oxides are essential materials in the production process of nuclear fuel for civilian or military applications. As such, identifying their...  相似文献   
48.
49.
The formation of apoptosis‐inducing amyloidal structures by metabolites has significantly extended the “amyloid hypothesis” to include non‐proteinaceous, single metabolite building blocks. However, detection of metabolite assemblies is restricted compared to their larger protein‐based counterparts owing to the hindrance of external labelling and limited immunohistochemical detection tools. Herein, we present the detection of the formation, dynamics, and cellular distribution of metabolite amyloid‐like structures and provide mechanistic insights into the generation of supramolecular chromophores. Moreover, the intrinsic fluorescence properties allow the detection of metabolite assemblies in living cells without the use of external dyes. Altogether, this intrinsic fluorescence of metabolite assemblies further verifies their amyloidal nature, while providing an important tool for further investigation of their pathological role in inborn error of metabolism disorders.  相似文献   
50.
Jojoba (Simmondsia chinensis (Link) Schneider) wax is used for various dermatological and pharmaceutical applications. Several reports have previously shown beneficial properties of Jojoba wax and extracts, including antimicrobial activity. The current research aimed to elucidate the impact of Jojoba wax on skin residential bacterial (Staphylococcus aureus and Staphylococcus epidermidis), fungal (Malassezia furfur), and virus infection (herpes simplex 1; HSV-1). First, the capacity of four commercial wax preparations to attenuate their growth was evaluated. The results suggest that the growth of Staphylococcus aureus, Staphylococcus epidermidis, and Malassezia furfur was unaffected by Jojoba in pharmacologically relevant concentrations. However, the wax significantly attenuated HSV-1 plaque formation. Next, a complete dose–response analysis of four different Jojoba varieties (Benzioni, Shiloah, Hatzerim, and Sheva) revealed a similar anti-viral effect with high potency (EC50 of 0.96 ± 0.4 µg/mL) that blocked HSV-1 plaque formation. The antiviral activity of the wax was also confirmed by real-time PCR, as well as viral protein expression by immunohistochemical staining. Chemical characterization of the fatty acid and fatty alcohol composition was performed, showing high similarity between the wax of the investigated varieties. Lastly, our results demonstrate that the observed effects are independent of simmondsin, repeatedly associated with the medicinal impact of Jojoba wax, and that Jojoba wax presence is required to gain protection against HSV-1 infection. Collectively, our results support the use of Jojoba wax against HSV-1 skin infections.  相似文献   
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