Higher-order Moment Portfolio Optimization via The Difference-of-Convex Programming and Sums-of-Squares

We are interested in developing a Difference-of-Convex (DC) programming approach based on Difference-of-Convex-Sums-of-Squares (DC-SOS) decomposition techniques for high-order moment (Mean-Variance-Skewness-Kurtosis) portfolio optimization model. This problem can be formulated as a nonconvex quartic multivariate polynomial optimization, then a DC programming formulation based on the recently developed DC-SOS decomposition is investigated. We can use a well-known DC algorithm, namely DCA, for its numerical solution. Moreover, an acceleration technique for DCA, namely Boosted-DCA (BDCA), based on an inexact line search (Armijo-type line search) to accelerate the convergence of DCA for smooth and nonsmooth DC program with convex constraints is proposed. This technique is applied to DCA based on DC-SOS decomposition, and DCA based on universal DC decomposition. Numerical simulations of DCA and Boosted-DCA on synthetic and real datasets are reported. Comparisons with some non-dc programming based optimization solvers (KNITRO, FILTERSD, IPOPT and MATLAB fmincon) demonstrate that our Boosted-DC algorithms can achieve same numerical results with good performance comparable to these efficient methods on solving the high-order moment portfolio optimization model.Comment: 42 pages, 13 figure

A novel prognostic scoring model based on copper homeostasis and cuproptosis which indicates changes in tumor microenvironment and affects treatment response

Background: Intracellular copper homeostasis requires a complex system. It has shown considerable prospects for intervening in the tumor microenvironment (TME) by regulating copper homeostasis and provoking cuproptosis. Their relationship with hepatocellular carcinoma (HCC) remains elusive.Methods: In TCGA and ICGC datasets, LASSO and multivariate Cox regression were applied to obtain the signature on the basis of genes associated with copper homeostasis and cuproptosis. Bioinformatic tools were utilized to reveal if the signature was correlated with HCC characteristics. Single-cell RNA sequencing data analysis identified differences in tumor and T cells’ pathway activity and intercellular communication of immune-related cells. Real-time qPCR analysis was conducted to measure the genes’ expression in HCC and adjacent normal tissue from 21 patients. CCK8 assay, scratch assay, transwell, and colony formation were conducted to reveal the effect of genes on in vitro cell proliferation, invasion, migration, and colony formation.Results: We constructed a five-gene scoring system in relation to copper homeostasis and cuproptosis. The high-risk score indicated poor clinical prognosis, enhanced tumor malignancy, and immune-suppressive tumor microenvironment. The T cell activity was markedly reduced in high-risk single-cell samples. The high-risk HCC patients had a better expectation of ICB response and reactivity to anti-PD-1 therapy. A total of 156 drugs were identified as potential signature-related drugs for HCC treatment, and most were sensitive to high-risk patients. Novel ligand-receptor pairs such as FASLG, CCL, CD40, IL2, and IFN-Ⅱ signaling pathways were revealed as cellular communication bridges, which may cause differences in TME and immune function. All crucial genes were differentially expressed between HCC and paired adjacent normal tissue. Model-constructed genes affected the phosphorylation of mTOR and AKT in both Huh7 and Hep3B cells. Knockdown of ZCRB1 impaired the proliferation, invasion, migration, and colony formation in HCC cell lines.Conclusion: We obtained a prognostic scoring system to forecast the TME changes and assist in choosing therapy strategies for HCC patients. In this study, we combined copper homeostasis and cuproptosis to show the overall potential risk of copper-related biological processes in HCC for the first time

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Composite Film Based on Pulping Industry Waste and Chitosan for Food Packaging

Wood auto-hydrolysates (WAH) are obtained in the pulping process by the hydrothermal extraction, which contains lots of hemicelluloses and slight lignin. WAH and chitosan (CS) were introduced into this study to construct WAH-based films by the casting method. The FT-IR results revealed the crosslinking interaction between WAH and CS due to the Millard reaction. The morphology, transmittance, thermal properties and mechanical properties of composite WAH/CS films were investigated. As the results showed, the tensile strength, light transmittances and thermal stability of the WAH-based composite films increased with the increment of WAH/CS content ratio. In addition, the results of oxygen transfer rate (OTR) and water vapor permeability (WVP) suggested that the OTR and WVP values of the films decreased due to the addition of CS. The maximum value of tensile strengths of the composite films achieved 71.2 MPa and the OTR of the films was low as 0.16 cm3·μm·m−2·24 h−1·kPa−1, these properties are better than those of other hemicelluloses composite films. These results suggested that the barrier composite films based on WAH and CS will become attractive in the food packaging application for great mechanical properties, good transmittance and low oxygen transfer rate

Well-Defined Metal–O₆ in Metal–Catecholates as a Novel Active Site for Oxygen Electroreduction

Metal–nitrogen coordination sites, M–N_<i>x</i> (M = Fe, Co, Ni, etc.), have shown great potential to replace platinum group materials as electrocatalysts for oxygen reduction reaction (ORR). However, the real active site in M–N_<i>x</i> is still vague to date due to their complicated structure and composition. It is therefore highly desirable but challenging to develop ORR catalysts with novel and clear active sites, which could meet the needs of comprehensive understanding of structure–function relationships and explore new cost-effective and efficient ORR electrocatalysts. Herein, well-defined M–O₆ coordination in metal–catecholates (M–CATs, M = Ni or Co) is discovered to be catalytically active for ORR via a four-electron-dominated pathway. In view of no pyrolysis involved and unambiguous crystalline structure of M–CATs, the M–O₆ octahedral coordination site with distinct structure is determined as a new type of active site for ORR. These findings extend the scope of metal–nonmetal coordination as an active site for ORR and pave a way for bottom-up design of novel electrocatalysts containing M–O₆ coordination