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We propose in this work a hybrid improvement procedure for the bin packing problem. This heuristic has several features: the use of lower bounding strategies; the generation of initial solutions by reference to the dual min-max problem; the use of load redistribution based on dominance, differencing, and unbalancing; and the inclusion of an improvement process utilizing tabu search. Encouraging results have been obtained for a very wide range of benchmark instances, illustrating the robustness of the algorithm. The hybrid improvement procedure compares favourably with all other heuristics in the literature. It improved the best known solutions for many of the benchmark instances and found the largest number of optimal solutions with respect to the other available approximate algorithms.  相似文献   
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Purpose: Vascular targeted photodynamic therapy (VTP) is a nonsurgical tumor ablation approach used to treat early-stage prostate cancer and may also be effective for upper tract urothelial cancer (UTUC) based on preclinical data. Toward increasing response rates to VTP, we evaluated its efficacy in combination with concurrent PD-1 inhibitor/OX40 agonist immunotherapy in a urothelial tumor-bearing model. Experimental design: In mice allografted with MB-49 UTUC cells, we compared the effects of combined VTP with PD-1 inhibitor/OX40 agonist with those of the component treatments on tumor growth, survival, lung metastasis, and antitumor immune responses. Results: The combination of VTP with both PD-1 inhibitor and OX40 agonist inhibited tumor growth and prolonged survival to a greater degree than VTP with either immunotherapeutic individually. These effects result from increased tumor infiltration and intratumoral proliferation of cytotoxic and helper T cells, depletion of Treg cells, and suppression of myeloid-derived suppressor cells. Conclusions: Our findings suggest that VTP synergizes with PD-1 blockade and OX40 agonist to promote strong antitumor immune responses, yielding therapeutic efficacy in an animal model of urothelial cancer.  相似文献   
3.
POPMUSIC for the point feature label placement problem   总被引:1,自引:0,他引:1  
Point feature label placement is the problem of placing text labels adjacent to point features on a map so as to maximize legibility. The goal is to choose positions for the labels that do not give rise to label overlaps and that minimize obscuration of features. A practical goal is to minimize the number of overlaps while considering cartographic preferences. This article proposes a new heuristic for solving the point feature label placement problem based on the application of the POPMUSIC frame. Computational experiments show that the proposed heuristic outperformed other recent metaheuristics approaches in the literature. Experiments with problem instances involving up to 10 million points show that the computational time of the proposed heuristic increases almost linearly with the problem size. New problem instances based on real data with more than 13,000 labels are proposed.  相似文献   
4.
A suitable weak topology is considered on the Hilbert phase space of a quantum-mechanical system. It is then shown that if two bounded observables of the system have no common eigenvector, the sum of their variances in any state is always greater than some positive constant. Consequences of this result on some observables of simple physical systems are examined. First of all, the case of the position and momentum of the elementary particle in one dimension is studied and a comparation with Heisenberg's indeterminacy principle is carried out. Then, the case of angular variables is also examined, with special emphasis on spin 1/2. An experiment with neutrons is finally suggested and analysed with the help of the theory developed.  相似文献   
5.
A methodology based on microwave‐assisted extraction (MAE) and LC with fluorescence detection (FLD) was investigated for the efficient determination of 15 polycyclic aromatic hydrocarbons (PAHs) regarded as priority pollutants by the US Environmental Protection Agency and dibenzo(a,l)pyrene in atmospheric particulate samples. PAHs were successfully extracted from real outdoor particulate matter (PM) samples with recoveries ranging from 81.4 ± 8.8 to 112.0 ± 1.1%, for all the compounds except for naphthalene (62.3 ± 18.0%) and anthracene (67.3 ± 5.7%), under the optimum MAE conditions (30.0 mL of ACN for 20 min at 110°C). No clean‐up steps were necessary prior to LC analysis. LOQs ranging from 0.0054 ng/m3 for benzo(a)anthracene to 0.089 ng/m3 for naphthalene were reached. The validated MAE methodology was applied to the determination of PAHs from a set of real world PM samples collected in Oporto (north of Portugal). The sum of particulate‐bound PAHs in outdoor PM ranged from 2.5 and 28 ng/m3.  相似文献   
6.
With improved understanding of cancer biology and technical advancements in non-invasive management of urological malignancies, there is renewed interest in photodynamic therapy (PDT) as a means of focal cancer treatment. The application of PDT has also broadened as a result of development of better-tolerated and more effective photosensitizers. Vascular-targeted PDT (VTP) using padeliporfin, which is a water-soluble chlorophyll derivative, allows for tumor-specific cytotoxicity and has demonstrated efficacy in the management of urologic malignancies. Herein, we describe the evolution of photodynamic therapy in urologic oncology and the role of VTP in emerging treatment paradigms.  相似文献   
7.
Preparation of high-quality proteins from cacao vegetative organs is difficult due to very high endogenous levels of polysaccharides and polyphenols. In order to establish a routine procedure for the application of proteomic and biochemical analysis to cacao tissues, three new protocols were developed; one for apoplastic washing fluid (AWF) extraction, and two for protein extraction--under denaturing and nondenaturing conditions. The first described method allows a quick and easy collection of AWF--using infiltration-centrifugation procedure--that is representative of its composition in intact leaves according to the smaller symplastic contamination detected by the use of the hexose phosphate isomerase marker. Protein extraction under denaturing conditions for 2-DE was remarkably improved by the combination of chemically and physically modified processes including phenol, SDS dense buffer and sonication steps. With this protocol, high-quality proteins from cacao leaves and meristems were isolated, and for the first time well-resolved 1-DE and 2-DE protein patterns of cacao vegetative organs are shown. It also appears that sonication associated with polysaccharide precipitation using tert-butanol was a crucial step for the nondenaturing protein extraction and subsequent enzymatic activity detection. It is expected that the protocols described here could help to develop high-level proteomic and biochemical studies in cacao also being applicable to other recalcitrant plant tissues.  相似文献   
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