Fix-and-Optimize and Variable Neighborhood Search Approaches for Stochastic Multi-Item Capacitated Lot-Sizing Problems

We discuss stochastic multi-item capacitated lot-sizing problems with and without setup carryovers (also known as link lot size), S-MICLSP and S-MICLSP-L. The two models are motivated from a real-world steel enterprise. To overcome the nonlinearity of the models, a piecewise linear approximation method is proposed. We develop a new fix-and-optimize (FO) approach to solve the approximated models. Compared with the existing FO approach(es), our FO is based on the concept of “k-degree-connection” for decomposing the problems. Furthermore, we also propose an integrative approach combining our FO and variable neighborhood search (FO-VNS), which can improve the solution quality of our FO approach by diversifying the search space. Numerical experiments are performed on the instances following the nature of realistic steel products. Our approximation method is shown to be efficient. The results also show that the proposed FO and FO-VNS approaches significantly outperform the recent FO approaches, and the FO-VNS approaches can be more outstanding on the solution quality with moderate computational effort

Inflammatory microenvironment in the initiation and progression of bladder cancer

Accumulating evidence suggests the idea that chronic inflammation may play a critical role in various malignancies including bladder cancer and long-term treatment with non-steroidal anti-inflammatory drugs (NSAIDs) is significantly effective in reducing certain cancer incidence and mortality. However, the molecular mechanisms leading to malignant transformation and the progression of bladder cancer in a chronically inflammatory environment remain largely unknown. In this review, we will describe the role of inflammation in the formation and development of bladder cancer and summarize the possible molecular mechanisms by which chronic inflammation regulates cell immune response, proliferation and metastasis. Understanding the novel function orchestrating inflammation and bladder cancer will hopefully provide us insights into their future clinical significance in preventing bladder carcinogenesis and progression

LC-MS/MS Quantification of Nevirapine and Its Metabolites in Hair for Assessing Long-Term Adherence

The adherence assessment based on the combination of nevirapine (NVP) and its two metabolites (2-hydroxynevirapine and 3-hydroxynevirapine) would more comprehensively and accurately reflect long-term adherence than that of a single prototype. This study aimed to develop a specific, sensitive and selective method for simultaneous detection of the three compounds in hair and explore whether there was consistency among the three compounds in assessing long-term adherence. Furthermore, 75 HIV-positive patients who were taking the NVP drug were randomly recruited and divided into two groups (high-and low-adherence group). All participants self-reported their days of oral drug administration per month and provided their hair strands closest to the scalp at the region of posterior vertex. The concentrations of three compounds in the hair were determined using a developed LC-MS/MS method in multiple reaction monitoring. This method showed good performances in limit of quantification and accuracy with the recoveries from 85 to 115% and in precision with the intra-day and inter-day coefficients of variation within 15% for the three compounds. The population analysis revealed that patients with high-adherence showed significantly higher concentrations than those with low-adherence for all three compounds. There were significantly moderate correlations of nevirapine with 2-hydroxynevirapine and 3-hydroxynevirapin and high correlation between 2-hydroxynevirapine and 3-hydroxynevirapin. The two NVP’s metabolites showed high consistency with NVP in evaluating long-term adherence

Design and fatigue analysis of diagonally reinforced structures with a negative Poisson’s ratio lattice material

In this paper, a typical negative Poisson’s ratio lattice structure was studied and several diagonally reinforced 3D lattice structures were designed and analysed using the finite element method. On this basis, the fatigue life of the unreinforced and reinforced structures was calculated using SIMULIA Fe-safe software. Meanwhile, the fatigue failure process of the lattice structure was systematically simulated and quantitatively analysed by combining the multiaxial fatigue damage model. Results show that the enhancement design from the cell structure can provide an anti-diagonal shear enhancement effect. The structure A, B, and C can decrease the maximum von Mises stress by 95.8, 97.1, and 94.66%, and increase the compressibility by 80%, 56%, and 127%, respectively. The structure A enhancement yields the best overall performance in terms of structural stress, compressibility, and negative Poisson’s ratio properties enhancement. Compared with the unreinforced structure, the lifetime distribution of the structure A reinforced structure changes in both position and level. The overall lifetime has been improved from 10 ^2.813 of the unreinforced structure to 10 ^7 of the reinforced structure. Quantitative calculation of the fatigue damage is consistent with the fatigue life prediction results, which further validate the effectiveness of the diagonal enhancement method and the enhancement structure of the negative Poisson’s ratio lattice structure

An Automatic Fault Diagnosis Method for the Reciprocating Compressor Based on HMT and ANN

The health management of the reciprocating compressor is crucial for its long term steady operation and safety. Online condition monitoring technology for the reciprocating compressor is almost mature, whereas the fault diagnosis technologies are still insufficient to meet the need. Therefore, in this paper, a novel fault detection method for the reciprocating compressor based on digital image processing and artificial neural network (ANN) was proposed. This method is implemented to the sectionalized pressure–volume (p–V) curves, which are obtained by dividing a working cycle in the cylinder into four thermal processes, including expansion, suction, compression and discharge. Hit-or-miss transform is adopted to extract the comprehensive gradients of expansion and compression curves, and vertical projection transform is applied to extract the vertical projection features. Finally, all of the features are fed to an ANN to do classification. To validate the proposed method, a seeded fault testing was conducted to collect real running data. The results showed that the new approach shows a good performance, with a high classification accuracy of 97.9%

Low molecular weight heparin synergistically enhances the efficacy of adoptive and anti-PD-1-based immunotherapy by increasing lymphocyte infiltration in colorectal cancer

Background Immunotherapy, including adoptive cell therapy (ACT) and immune checkpoint inhibitors (ICIs), has a limited effect in most patients with colorectal cancer (CRC), and the efficacy is further limited in patients with liver metastasis. Lack of antitumor lymphocyte infiltration could be a major cause, and there remains an urgent need for more potent and safer therapies for CRC.Methods In this study, the antitumoral synergism of low molecular weight heparin (LMWH) combined with immunotherapy in the microsatellite stable (MSS) highly aggressive murine model of CRC was fully evaluated.Results Dual LMWH and ACT objectively mediated the stagnation of tumor growth and inhibition of liver metastasis, neither LMWH nor ACT alone had any antitumoral activity on them. The combination of LMWH and ACT obviously increased the infiltration of intratumor CD8+ T cells, as revealed by multiplex immunohistochemistry, purified CD8+ T-cell transfer assay, and IVIM in vivo imaging. Mechanistically, evaluation of changes in the tumor microenvironment revealed that LMWH improved tumor vascular normalization and facilitated the trafficking of activated CD8+ T cells into tumors. Similarly, LMWH combined with anti-programmed cell death protein 1 (PD-1) therapy provided superior antitumor activity as compared with the single PD-1 blockade in murine CT26 tumor models.Conclusions LMWH could enhance ACT and ICIs-based immunotherapy by increasing lymphocyte infiltration into tumors, especially cytotoxic CD8+ T cells. These results indicate that combining LMWH with an immunotherapy strategy presents a promising and safe approach for CRC treatment, especially in MSS tumors

Effects of light on the resistivity of chemical vapor deposited graphene films

This article reports that the resistance of a chemical vapor deposition (CVD) grown graphene film transferred onto an SiO₂ substrate increases to higher saturation values upon exposure to light of decreasing wavelength from the visible to ultraviolet

LC-MS/MS Quantification of Nevirapine and Its Metabolites in Hair for Assessing Long-Term Adherence

The adherence assessment based on the combination of nevirapine (NVP) and its two metabolites (2-hydroxynevirapine and 3-hydroxynevirapine) would more comprehensively and accurately reflect long-term adherence than that of a single prototype. This study aimed to develop a specific, sensitive and selective method for simultaneous detection of the three compounds in hair and explore whether there was consistency among the three compounds in assessing long-term adherence. Furthermore, 75 HIV-positive patients who were taking the NVP drug were randomly recruited and divided into two groups (high-and low-adherence group). All participants self-reported their days of oral drug administration per month and provided their hair strands closest to the scalp at the region of posterior vertex. The concentrations of three compounds in the hair were determined using a developed LC-MS/MS method in multiple reaction monitoring. This method showed good performances in limit of quantification and accuracy with the recoveries from 85 to 115% and in precision with the intra-day and inter-day coefficients of variation within 15% for the three compounds. The population analysis revealed that patients with high-adherence showed significantly higher concentrations than those with low-adherence for all three compounds. There were significantly moderate correlations of nevirapine with 2-hydroxynevirapine and 3-hydroxynevirapin and high correlation between 2-hydroxynevirapine and 3-hydroxynevirapin. The two NVP’s metabolites showed high consistency with NVP in evaluating long-term adherence