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911.
We study generalized complex cohomologies of generalized complex structures constructed from certain symplectic fiber bundles over complex manifolds. We apply our results in the case of left-invariant generalized complex structures on nilmanifolds and to their space of small deformations. 相似文献
912.
We define the concept of reproducible map and show that, whenever the constraint map defining the quasivariational inequality (QVI) is reproducible then one can characterize the whole solution set of the QVI as a union of solution sets of some variational inequalities (VI). By exploiting this property, we give sufficient conditions to compute any solution of a generalized Nash equilibrium problem (GNEP) by solving a suitable VI. Finally, we define the class of pseudo-Nash equilibrium problems, which are (not necessarily convex) GNEPs whose solutions can be computed by solving suitable Nash equilibrium problems. 相似文献
913.
A novel method for the UHPLC–MS/MS analysis of (E)-4-hydroxynonenal (4-HNE) is described. The method is based on derivatization of 4-HNE with pentafluorophenylhydrazine (1) or 4-trifluoromethylphenylhydrazine (2) in acetonitrile in the presence of trifluoroacetic acid as catalyst at room temperature and allows complete analysis of one sample of vegetable oil in only 21 min, including sample preparation and chromatography. The method involving hydrazine 1, implemented in an ion trap instrument with analysis of the transition m/z 337 → 154 showed LOD = 10.9 nM, average accuracy of 101% and precision ranging 2.5–4.0% RSD intra-day (2.7–4.1% RSD inter-day), with 4-HNE standard solutions. Average recovery from lipid matrices was 96.3% from vaseline oil, 91.3% from sweet almond oil and 105.3% from olive oil. The method was tested on the assessment of safety and oxidative degradation of seven samples of dietary oil (soybean, mixed seeds, corn, peanut, sunflower, olive) and six cosmetic-grade oils (avocado, blackcurrant, apricot kernel, echium, sesame, wheat germ) and effectively detected increased 4-HNE levels in response to chemical (Fenton reaction), photochemical, or thermal stress and aging, aimed at mimicking typical oxidation associated with storage or industrial processing. The method is a convenient, cost-effective and reliable tool to assess quality and safety of vegetable oils. 相似文献
914.
915.
Simone Franchini 《Stochastic Processes and their Applications》2017,127(10):3372-3411
We consider a generalized two-color Polya urn (black and white balls) first introduced by Hill et al. (1980), where the urn composition evolves as follows: let , and denote by the fraction of black balls after step , then at step a black ball is added with probability and a white ball is added with probability . Originally introduced to mimic attachment under imperfect information, this model has found applications in many fields, ranging from Market Share modeling to polymer physics and biology.In this work we discuss large deviations for a wide class of continuous urn functions . In particular, we prove that this process satisfies a Sample-Path Large Deviations principle, also providing a variational representation for the rate function. Then, we derive a variational representation for the limit where is the number of black balls at time , and use it to give some insight on the shape of . Under suitable assumptions on we are able to identify the optimal trajectory. We also find a non-linear Cauchy problem for the Cumulant Generating Function and provide an explicit analysis for some selected examples. In particular we discuss the linear case, which embeds the Bagchi–Pal Model [6], giving the exact implicit expression for in terms of the Cumulant Generating Function. 相似文献
916.
A Comparison of Dose Metrics to Predict Local Tumor Control for Photofrin‐mediated Photodynamic Therapy
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Haixia Qiu Michele M. Kim Rozhin Penjweini Jarod C. Finlay Theresa M. Busch Tianhao Wang Wensheng Guo Keith A. Cengel Charles B. Simone II Eli Glatstein Timothy C. Zhu 《Photochemistry and photobiology》2017,93(4):1115-1122
This preclinical study examines light fluence, photodynamic therapy (PDT) dose and “apparent reacted singlet oxygen,” [1O2]rx, to predict local control rate (LCR) for Photofrin‐mediated PDT of radiation‐induced fibrosarcoma (RIF) tumors. Mice bearing RIF tumors were treated with in‐air fluences (50–250 J cm?2) and in‐air fluence rates (50–150 mW cm?2) at Photofrin dosages of 5 and 15 mg kg?1 and a drug‐light interval of 24 h using a 630‐nm, 1‐cm‐diameter collimated laser. A macroscopic model was used to calculate [1O2]rx and PDT dose based on in vivo explicit dosimetry of the drug concentration, light fluence and tissue optical properties. PDT dose and [1O2]rx were defined as a temporal integral of drug concentration and fluence rate, and singlet oxygen concentration consumed divided by the singlet oxygen lifetime, respectively. LCR was stratified for different dose metrics for 74 mice (66 + 8 control). Complete tumor control at 14 days was observed for [1O2]rx ≥ 1.1 mm or PDT dose ≥1200 μm J cm?2 but cannot be predicted with fluence alone. LCR increases with increasing [1O2]rx and PDT dose but is not well correlated with fluence. Comparing dosimetric quantities, [1O2]rx outperformed both PDT dose and fluence in predicting tumor response and correlating with LCR. 相似文献
917.
918.
Andrea Mariela Araya‐Sibaja Valdir Soldi Carlos Eduardo Maduro de Campos Simone Gonalves Cardoso Silvia Lucia Cuffini 《Crystal Research and Technology》2016,51(1):49-57
The selective crystallization of progesterone polymorphs prepared by Polymer‐Induced Heteronucleation (PIHn) method was investigated. Polyvinyl alcohol (PVA), hydroxypropyl methylcellulose (HPMC), dextran, gelatin, polyisoprene (PI), and acrylonitrile/butadiene copolymer (NBR) were used as heteronucleants. Crystallizations were conducted from 0.5, 10 and 40 mg mL−1 solutions in chloroform at room temperature by solvent evaporation. The samples were characterized by X‐ray powder diffraction, differential scanning calorimetry, infrared spectroscopy and scanning electron microscopy. Form 2 was obtained from 0.5 mg mL−1 solution in almost all polymers. A mixture of both polymorphs crystallized from the three concentrations on gelatine; from 10 and 40mg mL−1 on PVA and HPMC and, from 10 mg mL−1 solutions on NBR. Form 2 crystallized on HPMC was stable for three months under ambient stress conditions (40ºC and 75% RH). These results are good evidence that the tailoring of new formulations and devices with progesterone the metastable and more soluble form 2 is possible. 相似文献
919.
Quantum optimal control theory allows us to design accurate quantum gates. We employ it to design high-fidelity two-bit gates for Josephson charge qubits in the presence of both leakage and noise. Our protocol considerably increases the fidelity of the gate and, more important, it is quite robust in the disruptive presence of 1/f noise. The improvement in the gate performances discussed in this work (errors approximately 10(-3)-10(-4) in realistic cases) allows us to cross the fault tolerance threshold. 相似文献
920.
Dalla Bella S Giguère JF Peretz I 《The Journal of the Acoustical Society of America》2007,121(2):1182-1189
Most believe that the ability to carry a tune is unevenly distributed in the general population. To test this claim, we asked occasional singers (n=62) to sing a well-known song in both the laboratory and in a natural setting (experiment 1). Sung performances were judged by peers for proficiency, analyzed for pitch and time accuracy with an acoustic-based method, and compared to professional singing. The peer ratings for the proficiency of occasional singers were normally distributed. Only a minority of the occasional singers made numerous pitch errors. The variance in singing proficiency was largely due to tempo differences. Occasional singers tended to sing at a faster tempo and with more pitch and time errors relative to professional singers. In experiment 2 15 nonmusicians from experiment 1 sang the same song at a slow tempo. In this condition, most of the occasional singers sang as accurately as the professional singers. Thus, singing appears to be a universal human trait. However, two of the occasional singers maintained a high rate of pitch errors at the slower tempo. This poor performance was not due to impaired pitch perception, thus suggesting the existence of a purely vocal form of tone deafness. 相似文献