Set multi-covering via inclusion-exclusion

Set multi-covering is a generalization of the set covering problem where each element may need to be covered more than once and thus some subset in the given family of subsets may be picked several times for minimizing the number of sets to satisfy the coverage requirement. In this paper, we propose a family of exact algorithms for the set multi-covering problem based on the inclusion-exclusion principle. The presented ESMC (Exact Set Multi-Covering) algorithm takes O* ((2 t)n) time and O* ((t + 1)n) space where t is the maximum value in the coverage requirement set (The O* (f (n)) notation omits a p o l y log (f (n)) factor). We also propose the other three exact algorithms through different tradeoffs of the time and space complexities. To the best of our knowledge, this present paper is the first one to give exact algorithms for the set multi-covering problem with nontrivial time and space complexities. This paper can also be regarded as a generalization of the exact algorithm for the set covering problem given in [A. Björklund, T. Husfeldt, M. Koivisto, Set partitioning via inclusion-exclusion, SIAM Journal on Computing, in: FOCS 2006 (in press, special issue)]. © 2009 Elsevier B.V. All rights reserved.postprin

Impact of melt rheology on zein foam properties

Zein, the main protein fraction in maize, is left as a by-product from bio-ethanol production. The protein has been investigated as a material for a long time, but mainly in the form of films. In contrast, foamed zein is presented in this article. Zein foams may perhaps be used, e.g. as trays for biodegradable food packages or as scaffolds for tissue engineering. A batch method for manufacturing solid foams was successfully developed, the foams being manufactured by evaporation of solvent from zein resins. In order to be suitable for foam formation, a resin must possess gas-retaining properties, which can be predicted by extensional rheology. The presence of plasticizer in some of the resins decreased their extensional viscosity, and this in turn affected the foaming process. Although all the resins displayed strain-hardening behaviour, there was coalescence of pores in all the foams. Insufficient extensional viscosity resulted in the collapse of pore walls during foam expansion. Structure analysis showed, e.g. that most pores were elongated along the main axis of the mould in which the foams were manufactured. The plasticizer content in the resins had no significant effect on the mechanical properties of the foams

Isolation of flavonoids from mulberry (Morus alba L.) leaves with macroporous resins

Flavonoids are major active constituents in mulberry (Morus alba L.) leaves and possess various pharmacological activities. In the present study, the extraction technology and preparative separation oftotal flavonoids (TFs) in mulberry leaves extracts by macroporous resins were studied systematically, and the column packed with selected resin was used to perform dynamic adsorption and desorptiontests to optimize the separation process. The research results indicated that the maximal yield of TFs was achieved when mulberry leaves were extracted under the optimized conditions of a pH of 8, asolid-liquid ratio of 1:40, a temperature of 90oC and a time of 4 h. H103 resin is the most appropriate for the separation of TFs from other components in mulberry leaves extracts, which adsorption behavior canbe described with Langmuir and Freundlich isotherms and two-step adsorption kinetics model. The optimum parameters for TFs separation by H103 were achieved, after one run treatment. The recoveryand purity of TFs in the final product were 90.57 and 76.33%, respectively. In conclusion, the preparative separation of TFs in mulberry leaves can be easily and effectively done by H103 resin

Electron shuttle-mediated microbial Fe(III) reduction under alkaline conditions

Purpose: Extracellular Fe(III) reduction plays an important role in a variety of biogeochemical processes. Several mechanisms for microbial Fe(III) reduction in pH-neutral environments have been proposed, but pathways of microbial Fe(III) reduction within alkaline conditions have not been clearly identified. Alkaline soils are vastly distributed; thus, a better understanding of microbial Fe(III) reduction under alkaline conditions is of significance. The purpose of this study is to explore the dominant mechanism of bacterial iron reduction in alkaline environments. Materials and methods: We used antraquinone-2,6-disulfonate (AQDS) as a representative of quinone moities of humic substances and elemental sulfur and sulfate as sulfur species to investigate the potential role of humic substances and sulfur species in mediating microbial Fe(III) reduction in alkaline environments. We carried out thermodynamic calculations to predict the ability of bacteria to reduce Fe(III) (oxyhydr)oxides under alkaline conditions and the ability of AQDS and sulfur species to serve as electron acceptors for microbial anaerobic respiration in an assumed alkaline soil environments. A series of incubation experiments with two model dissimilatory metal reducing bacteria, Shewanella oneidensis MR-1 and Geobacter sulfurreducens PCA as well as mixed bacteria enriched from a soil were performed to confirm the contribution of AQDS and sulfur species to Fe(III) reduction under alkaline conditions. Results and discussion: Based on thermodynamic calculations, we predicted that, under alkaline conditions, the enzymatic reduction of Fe(III) (oxyhydr)oxides would be thermodynamically feasible but very weak. In our incubation experiments, the reduction of ferrihydrite by anaerobic cultures of Shewanella oneidensis MR-1, Geobacter sulfurreducens PCA or microbes enriched from a soil was significantly increased in the presence of S0 or AQDS. Notably, AQDS contributed more to promoting Fe(III) reduction as a soluble electron shuttle than S0 did under the alkaline conditions probably because of different mechanisms of microbial utilization of AQDS and S0. Conclusions: These results suggest that microbial reduction of Fe(III) (oxyhydr)oxides under alkaline conditions may proceed via a pathway mediated by electron shuttles such as AQDS and S0. Considering the high ability of electron shuttling and vast distribution of humic substances, we suggest that humic substance-mediated Fe(III) reduction may potentially be the dominant mechanism for Fe(III) reduction in alkaline environments

Studies on Anti-Hepatoma Effect of Gan-Ai-Xiao Decoction

Purpose: To explore the anti-hepatoma effect of Gan-Ai-Xiao Decoction (GAXD), a folk remedy.Methods: High performance liquid chromatography (HPLC) was used to identify the major chemical components of GAXD ethanol extract (EE). The cytotoxic effect of GAXD EE against HepG2 cells was measured by methyl thiazolyl tetrazolium (MTT) assay. Flow cytometry and Western blot were used to study the effect of GAXD EE on apoptosis and apoptotic proteins (Bcl-2, Bax and caspase-3) in HepG2 cells. Xenograft assay was used to evaluate the anti-hepatoma effect of GAXD EE in vivo.Results: Four components were identified in GAXD EE by HPLC. The results of MTT and flow cytometry assays indicated that GAXD EE significantly reduced HepG2 cells viability (p < 0.05) and induced its apoptosis. The results of Western blot assay suggested that GAXD EE down-regulated the expression of anti-apoptotic protein (Bcl-2) and up-regulated the expression of pro-apoptotic proteins (Bax and caspase-3) in HepG2 cells. Furthermore, the results of xenograft assay showed that GAXD EE significantly inhibited the growth of HepG2 cells-induced tumor (p < 0.05) without any effect on the body weight of nude mice.Conclusion: GAXD has anti-hepatoma activity, and the mechanism is associated with apoptosis.Keywords: Gan-Ai-Xiao Decoction, Anti-hepatoma, Flow Cytometry, Western Blot, Xenograft, HepG2 cells, Apoptosi

Two Birds with One Stone? Possible Dual-Targeting H1N1 Inhibitors from Traditional Chinese Medicine

The H1N1 influenza pandemic of 2009 has claimed over 18,000 lives. During this pandemic, development of drug resistance further complicated efforts to control and treat the widespread illness. This research utilizes traditional Chinese medicine Database@Taiwan (TCM Database@Taiwan) to screen for compounds that simultaneously target H1 and N1 to overcome current difficulties with virus mutations. The top three candidates were de novo derivatives of xylopine and rosmaricine. Bioactivity of the de novo derivatives against N1 were validated by multiple machine learning prediction models. Ability of the de novo compounds to maintain CoMFA/CoMSIA contour and form key interactions implied bioactivity within H1 as well. Addition of a pyridinium fragment was critical to form stable interactions in H1 and N1 as supported by molecular dynamics (MD) simulation. Results from MD, hydrophobic interactions, and torsion angles are consistent and support the findings of docking. Multiple anchors and lack of binding to residues prone to mutation suggest that the TCM de novo derivatives may be resistant to drug resistance and are advantageous over conventional H1N1 treatments such as oseltamivir. These results suggest that the TCM de novo derivatives may be suitable candidates of dual-targeting drugs for influenza.National Science Council of Taiwan (NSC 99-2221-E-039-013-)Committee on Chinese Medicine and Pharmacy (CCMP100-RD-030)China Medical University and Asia University (CMU98-TCM)China Medical University and Asia University (CMU99-TCM)China Medical University and Asia University (CMU99-S-02)China Medical University and Asia University (CMU99-ASIA-25)China Medical University and Asia University (CMU99-ASIA-26)China Medical University and Asia University (CMU99-ASIA-27)China Medical University and Asia University (CMU99-ASIA-28)Taiwan Department of Health. Clinical Trial and Research Center of Excellence (DOH100-TD-B-111-004)Taiwan Department of Health. Cancer Research Center of Excellence (DOH100-TD-C-111-005

Early Treatment of Nevus of Ota in Children is More Effective and Beneficial to Mental Health: Observation on the Efficacy of Q-Switched Ruby Laser in Treating 159 Cases of Nevus of Ota in Children

Ji-Cong Jiang,&ast; Ying-Wei Wang,&ast; Yu Gao, Qi-Shuang Zhou Department of Dermatology, The Second Affiliated Hospital and Yuying Children’s Hospital of Wenzhou Medical University, Wenzhou, Zhejiang Province, 325027, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Qi-Shuang Zhou; Yu Gao, Email [email protected]; [email protected] and Objective: Nevus of Ota (NO), also known as “brownish-blue nevus of the palate of the eye”, is a benign dermal pigmentation that increases skin disease. The Q-switched ruby laser is a classic treatment for nevus of Ota in children, but the optimal age for treatment is still controversial. The aim of this study was to investigate the treatment effect of Q-switched ruby laser in children with nevus of Ota at different ages and the effect on psychological health status.Materials and Methods: Children with nevus of Ota treated with Q-switched ruby laser in the Department of Dermatology of the Second Affiliated Hospital of Wenzhou Medical University from June 2015 to June 2019 were retrospectively analysed. And the mental health status was assessed using the CDI scale.Results: In the preschool children group (0– 7 year age), the significant efficacy rates was 93.1%, the average number of treatments was 3.6, and the overall incidence of adverse reactions was 4.7%. The significant efficacy rates in the school-age children group (7– 14 year age) was 90.3%, the average number of treatments was 5.1, and the overall incidence of adverse reactions was 13.7%. The mean post-treatment CDI score in the preschool children group was 10.8, and 9.7% of children exceeding 19 points. The mean pre-treatment CDI score in the school-age children group was 17.3, and 24.6% of children exceeding 19 points. The mean post-treatment CDI score was 13.6 and 15.1% of children exceeded 19 points. The chi-square test for the significant efficacy rate of the two groups showed P> 0.05, which was not statistically significant. The significant efficacy rate of the preschool group and that of the school-age children group. The t-test for the number of treatments in the two groups showed P< 0.05, which was statistically significant. Adverse reactions in the two groups showed a statistically significant P< 0.05. The mean CDI scores and the percentage of depressed individuals in the school-age children group were significantly lower after treatment than before treatment (p< 0.05).Conclusion: Q-switched ruby laser is safe and effective in treating nevus of Ota in children. Early treatment can reduce the number of treatments and the incidence of adverse reactions. In addition, early treatment can reduce children’s depression, which is beneficial to mental health.Keywords: nevus of Ota, children, Q-switched ruby laser, early treatment, mental healt

The Antioxidant Protein Peroxiredoxin 4 Is Epigenetically Down Regulated in Acute Promyelocytic Leukemia

The antioxidant peroxiredoxin (PRDX) protein family comprises 6 members, which are implicated in a variety of cellular responses, including growth factor signal transduction. PRDX4 resides in the endoplasmic reticulum (ER), where it locally controls oxidative stress by reducing H2O2levels. We recently provided evidence for a regulatory function of PRDX4 in signal transduction from a myeloid growth factor receptor, the granulocyte colony-stimulating factor receptor (G-CSFR). Upon activation, the ligand-induced G-CSFR undergoes endocytosis and routes via the early endosomes where it physically interacts with ER-resident PRDX4. PRDX4 negatively regulates G-CSFR mediated signaling. Here, we investigated whether PRDX4 is affected in acute myeloid leukemia (AML); genomic alterations and expression levels of PRDX4 were investigated. We show that genomic abnormalities involving PRDX4 are rare in AML. However, we find a strong reduction in PRDX4 expression levels in acute promyelocytic leukemia (APL) compared to normal promyelocytes and different molecular subtypes of AML. Subsequently, the possible role of DNA methylation and histone modifications in silencing of PRDX4 in APLs was investigated. We show that the reduced expression is not due to methylation of the CpG island in the promoter region of PRDX4 but correlates with increased trimethylation of histone 3 lysine residue 27 (H3K27me3) and lysine residue 4 (H3K4me3) at the transcriptional start site (TSS) of PRDX4, indicative of a bivalent histone code involved in transcriptional silencing. These findings suggest that the control of G-CSF responses by the antioxidant protein PRDX4 may be perturbed in APL

A genetic cause of Alzheimer disease: mechanistic insights from Down syndrome

Down syndrome, caused by an extra copy of chromosome 21, is associated with a greatly increased risk of early onset Alzheimer disease. It is thought that this risk is conferred by the presence of three copies of the gene encoding amyloid precursor protein (APP), an Alzheimer risk factor, although the possession of extra copies of other chromosome 21 genes may also play a role. Further study of the mechanisms underlying the development of Alzheimer disease in Down syndrome could provide insights into the mechanisms that cause dementia in the general population