Determination of all semisymmetric recursive information measures of multiplicative type on n positive discrete probability distributions

AbstractInformation measures Δm (entropies, divergences, inaccuracies, information improvements, etc.), depending upon n probability distributions which we unite into a vector distribution, are recursive of type μ if Δm(p1, p2, p3,…,pm)=Δm−1(p1+p2, p3,…,pm)+μ(p1+p2)Δ2p1p1+p2,p2p1+p2. If also a similar equation holds with three instead of two distinguished vectors, then μ has to be multiplicative, except if all Δm are identically 0. The information measure is semisymmetric if Δ3(p1, p2, p3) = Δ3(p1, p3, p2). We determine all semisymmetric (in particular, symmetric) recursive information measures of multiplicative type, allowing first only positive probabilities. Previously the cases n ⪕ 3 have been examined mainly for μ(t) = μ(τ1, τ2,…, τn) = τ1α1 τ2α2 … τnαn and some probabilities were allowed to be 0. This has made the proofs easier. But permitting certain probabilities to be 0 would exclude most information measures important for applications, so the description of appropriate domains became complicated. However, we show how the measures which we determine here can be extended to the “old” domains and to more general ones

Scheduling jobs with agreeable processing times and due dates on a single batch processing machine

AbstractIn this paper we study the problems of scheduling jobs with agreeable processing times and due dates on a single batch processing machine to minimize total tardiness, and weighted number of tardy jobs. We prove that the problem of minimizing total tardiness is NP-hard even if the machine capacity is two jobs and we develop a pseudo-polynomial-time algorithm for an NP-hard special case of this problem. We also develop a pseudo-polynomial-time algorithm for the NP-hard problem of minimizing weighted number of tardy jobs, which suggests that this problem cannot be strongly NP-hard unless P=NP

Iron in the biology and treatment of gastrointestinal cancer

Background Iron is intimately related to the biology and pathology of gastrointestinal cancer with both iron excess and iron deficiency influencing disease. This thesis examines the biological and clinical effects of iron replacement in gastrointestinal cancer. Methods This thesis reports the effects of iron replacement in colorectal cancers at a biological level using immunohistochemistry, real time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) during clinical treatment for iron deficiency anaemia prior to surgery. Systematic review of the literature also investigates the clinical evidence for such an approach to pre-operative anaemia. The thesis then examines the natural history and impact of anaemia in oesophagogastric cancer before reporting a pilot randomised control study using intravenous iron to treat anaemia in this setting. Results Examining iron administration in colorectal cancer demonstrated that colorectal adenocarcinomas reprogram their iron metabolism to increase the potential labile iron pool. These changes appear to be decoupled from the normal intracellular iron sensing mechanisms. Route of administration of iron to patients did not alter tumour growth or effect iron transport mechanisms. Differential compartmentalisation of iron was noted however. Clinical anaemia in oesophagogastric cancer becomes more severe with time and treatment and was associated with poorer survival outcomes. Furthermore, higher initial haemoglobin, rather than just the absence of anaemia, was associated with better survival outcomes. In a randomised control pilot study for intravenous iron use compared to standard care for anaemia in oesophagogastric cancer, intravenous iron effectively replenished iron stores measured using ferritin and transferrin saturations. Despite chemotherapy and the tumour in situ the intravenous iron group saw an increase in haemoglobin. This was despite a significantly lower starting haemoglobin in the intravenous iron group. Quality of life was also significantly improved in the intravenous iron group. Conclusion This thesis supports the continued clinical use of intravenous iron for anaemia in gastrointestinal cancer, showing no deleterious effects at a biological level despite replenishment of iron stores and increases in haemoglobin at a clinical level. More research is required to investigate compartmentalisation of iron and conclude clinical efficacy in larger adequately powered studies

Analysis of radial variations in material properties and matrix composition of chondrocyte-seeded agarose hydrogel constructs

SummaryObjectiveTo examine the radial variations in engineered cartilage that may result due to radial fluid flow during dynamic compressive loading. This was done by evaluating the annuli and the central cores of the constructs separately.MethodChondrocyte-seeded agarose hydrogels were grown in free-swelling and dynamic, unconfined loading cultures for 42 days. After mechanical testing, constructs were allowed to recover for 1–2h, the central 3mm cores removed, and the cores and annuli were retested separately. Histological and/or biochemical analyses for DNA, glycosaminoglycan (GAG), collagen, type I collagen, type II collagen, and elastin were performed. Multiple regression analysis was used to determine the correlation between the biochemical and material properties of the constructs.ResultsThe cores and annuli of chondrocyte-seeded constructs did not exhibit significant differences in material properties and GAG content. Annuli possessed greater DNA and collagen content over time in culture than cores. Dynamic loading enhanced the material properties and GAG content of cores, annuli, and whole constructs relative to free-swelling controls, but it did not alter the radial variations compared to free-swelling culture.ConclusionSurprisingly, the benefits of dynamic loading on tissue properties extended through the entire construct and did not result in radial variations as measured via the coring technique in this study. Nutrient transport limitations and the formation of a fibrous capsule on the periphery may explain the differences in DNA and collagen between cores and annuli. No differences in GAG distribution may be due to sufficient chemical signals and building blocks for GAG synthesis throughout the constructs

Special issue on Structural Health Monitoring of Civil Structures

Ching-Tai Ng, Tommy H.T. Cha

Iron in the biology and treatment of gastrointestinal cancer

Background Iron is intimately related to the biology and pathology of gastrointestinal cancer with both iron excess and iron deficiency influencing disease. This thesis examines the biological and clinical effects of iron replacement in gastrointestinal cancer. Methods This thesis reports the effects of iron replacement in colorectal cancers at a biological level using immunohistochemistry, real time polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) during clinical treatment for iron deficiency anaemia prior to surgery. Systematic review of the literature also investigates the clinical evidence for such an approach to pre-operative anaemia. The thesis then examines the natural history and impact of anaemia in oesophagogastric cancer before reporting a pilot randomised control study using intravenous iron to treat anaemia in this setting. Results Examining iron administration in colorectal cancer demonstrated that colorectal adenocarcinomas reprogram their iron metabolism to increase the potential labile iron pool. These changes appear to be decoupled from the normal intracellular iron sensing mechanisms. Route of administration of iron to patients did not alter tumour growth or effect iron transport mechanisms. Differential compartmentalisation of iron was noted however. Clinical anaemia in oesophagogastric cancer becomes more severe with time and treatment and was associated with poorer survival outcomes. Furthermore, higher initial haemoglobin, rather than just the absence of anaemia, was associated with better survival outcomes. In a randomised control pilot study for intravenous iron use compared to standard care for anaemia in oesophagogastric cancer, intravenous iron effectively replenished iron stores measured using ferritin and transferrin saturations. Despite chemotherapy and the tumour in situ the intravenous iron group saw an increase in haemoglobin. This was despite a significantly lower starting haemoglobin in the intravenous iron group. Quality of life was also significantly improved in the intravenous iron group. Conclusion This thesis supports the continued clinical use of intravenous iron for anaemia in gastrointestinal cancer, showing no deleterious effects at a biological level despite replenishment of iron stores and increases in haemoglobin at a clinical level. More research is required to investigate compartmentalisation of iron and conclude clinical efficacy in larger adequately powered studies

Understanding General Activity Motivation for Persons with Stroke—A Reversal Theory Perspective

Introduction: Motivation is the barrier identified for clients with stroke to reintegrate community living. Reversal Therapy may help to understand the pattern of bipolar variations of motivational factors. This study analyzed the general activity motivation of clients with stroke and their relationship with community participation and mental wellbeing. Methodology: Sampling of 115 subjects including 30 stroke clients and 85 normal subjects. Measurements included the validated Chinese version of General Activity Motivation Measure (GAMM), Community Integration Questionnaire (CIQ) & Short Warwick Edinburgh Mental Wellbeing Scale (SWEMWBS). Results: In GAMM, the normal group scores (Mean 50.09 SD 5.79) higher then clients with stroke (Mean 46.09; SD 8.00) (p < 0.05). GAMM correlated positively with CIQ and SWEMWBS (p < 0.05). Four factors identified under GAMM namely Means-end, Relationship, Rules and Transactions that identified with Reversal Theory. Reversals between poles of each domain evidenced between two groups. “Acquiring new experiences” was strong predictor for community integration. Conclusion: Reversal Theory is useful to explain motivational changes among clients with stroke. To develop chances of “new experiences”, “feel accomplishment every day”, “get out of house regularly” and “to do the things that they can enjoy” at “their own pace” are the motivators for reintegrate into community living

Scattering characteristics of quasi-Scholte waves at blind holes in metallic plates with one side exposed to water

Corrosion is one of the major issues in metallic structures, especially those operating in humid environments and submerged in water. It is important to detect corrosion at its early stage to prevent further deterioration and catastrophic failures of the structures. Guided wave-based damage detection technique is one of the promising techniques for detecting and characterizing damage in structures. In water-immersed plate structures, most of the guided wave modes have strong attenuation due to energy leakage into the surrounding liquid. However, there is an interface wave mode known as quasi-Scholte waves, which can propagate with low attenuation. Therefore, this mode is promising for structural health monitoring (SHM) applications. This paper presents an analysis of the capability of quasi-Scholte waves in detecting internal corrosion-like defects in water-immersed structures. A three-dimensional (3D) finite element (FE) model is developed to simulate quasi-Scholte wave propagation and wave scattering phenomena on a steel plate with one side exposed to water. The accuracy of the model is validated through experimental measurements. There is good agreement between the FE simulations and experimental measurements. The experimentally verified 3D FE model is then employed in a series of parametric studies to analyze the scattering characteristics of quasi-Scholte waves at circular blind holes with different diameters and depths, which are the simplest representation of progressive corrosion. The findings of this study can enhance the understanding of quasi-Scholte waves scattering at corrosion damage of structures submerged in water and help improve the performance of in-situ damage detection techniques.Xianwen Hu, Ching Tai Ng, Andrei Kotouso

Bolted joint integrity monitoring with second harmonic generated by guided waves

In this study, the second harmonic generation due to the contact nonlinearity caused by bolt loosening is studied experimentally and numerically using three-dimensional explicit finite element simulations. In particular, it is demonstrated that the magnitude of the second harmonic generation normally increases with the loosening of the bolted joint, and there is a reasonable agreement between the numerical simulations and experimental results. The finite element model, which was validated against the experimentally measured data, is further utilized to investigate an important practical situation when a loosened bolt is weakened by fatigue cracks located at the edge of the hole. The numerical case studies show that the contact nonlinearity and the change of the behaviour of the second harmonic generation with the tightening level are very different to the corresponding results with the fatigue cracks. This identified difference in the second harmonic generation behaviour can serve as an indicator of the bolted joint integrity and thus provide early warning for engineers to make decision on the necessity of carrying out further safety inspections. Overall, the findings of this study provide improved physical insights into second harmonic generation for bolt loosening, which can be used to further advance damage detection techniques using nonlinear guided waves.Yi Yang, Ching-Tai Ng, Andrei Kotouso