64 research outputs found

    Properties of the Volume Operator in Loop Quantum Gravity II: Detailed Presentation

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    The properties of the Volume operator in Loop Quantum Gravity, as constructed by Ashtekar and Lewandowski, are analyzed for the first time at generic vertices of valence greater than four. The present analysis benefits from the general simplified formula for matrix elements of the Volume operator derived in gr-qc/0405060, making it feasible to implement it on a computer as a matrix which is then diagonalized numerically. The resulting eigenvalues serve as a database to investigate the spectral properties of the volume operator. Analytical results on the spectrum at 4-valent vertices are included. This is a companion paper to arXiv:0706.0469, providing details of the analysis presented there.Comment: Companion to arXiv:0706.0469. Version as published in CQG in 2008. More compact presentation. Sign factor combinatorics now much better understood in context of oriented matroids, see arXiv:1003.2348, where also important remarks given regarding sigma configurations. Subsequent computations revealed some minor errors, which do not change qualitative results but modify some numbers presented her

    Relationships Among Some Biochemical Parameters, Trace Elements and Lipid Peroxidation Levels in Women With Gestational Diabetes Mellitus

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    Aim:The aim of the present study was to determine levels of copper (Cu), zinc (Zn), iron (Fe), malondialdehyde and some biochemical parameters in women with gestational diabetes mellitus (GDM) compared with healthy pregnant women, and to evaluate the relationships among these parameters.Materials and Methods:The patients consisted of 56 pregnant with GDM. The control group consisted of 60 healthy pregnant women. Plasma malondialdehyde, blood glucose, insulin, glycosylated hemoglobin (HbA1c), total cholesterol, triacylglycerol and LDL-cholesterol were measured by biochemical methods. The concentrations of serum Fe, Cu and Zn were determined by flame atomic absorption spectrophotometer.Results:The levels of blood glucose, insulin, HOMA-IR, glycosylated hemoglobin (HbA1c), total cholesterol, triacylglycerol and LDL-cholesterol, levels of plasma malondialdehyde, levels of serum Fe and Cu in women with GDM group were found higher than those in healthy pregnant women. However, levels of serum Zn were significantly lower in GDM pregnants than those in the healthy pregnant women. There were significant negative correlations between LDL-cholesterol and Cu levels of GDM subjects. Additionally, there were significant negative correlation between LDL-cholesterol and plasma malondialdehyde levels. However, there were significant positive correlations between serum Fe and plasma malondialdehyde levels.Conclusion:Our findings emphasize the significant deficiencies of Zn levels and the significant elevation of malondialdehyde, hyperglycemia and hyperlipidemia in women with GDM. Therefore, supplementation with Zn element involved in the antioxidative system may increase antioxidative enzyme activities, and consequently, an improvement in fetal and maternal complications may be expected

    Predictive modelling of a novel anti-adhesion therapy to combat bacterial colonisation of burn wounds

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    As the development of new classes of antibiotics slows, bacterial resistance to existing antibiotics is becoming an increasing problem. A potential solution is to develop treatment strategies with an alternative mode of action. We consider one such strategy: anti-adhesion therapy. Whereas antibiotics act directly upon bacteria, either killing them or inhibiting their growth, anti-adhesion therapy impedes the binding of bacteria to host cells. This prevents bacteria from deploying their arsenal of virulence mechanisms, while simultaneously rendering them more susceptible to natural and artificial clearance. In this paper, we consider a particular form of anti-adhesion therapy, involving biomimetic multivalent adhesion molecule 7 coupled polystyrene microbeads, which competitively inhibit the binding of bacteria to host cells. We develop a mathematical model, formulated as a system of ordinary differential equations, to describe inhibitor treatment of a Pseudomonas aeruginosa burn wound infection in the rat. Benchmarking our model against in vivo data from an ongoing experimental programme, we use the model to explain bacteria population dynamics and to predict the efficacy of a range of treatment strategies, with the aim of improving treatment outcome. The model consists of two physical compartments: the host cells and the exudate. It is found that, when effective in reducing the bacterial burden, inhibitor treatment operates both by preventing bacteria from binding to the host cells and by reducing the flux of daughter cells from the host cells into the exudate. Our model predicts that inhibitor treatment cannot eliminate the bacterial burden when used in isolation; however, when combined with regular or continuous debridement of the exudate, elimination is theoretically possible. Lastly, we present ways to improve therapeutic efficacy, as predicted by our mathematical model

    Long-term follow-up results of a dorsal approach to complex dorsal metacarpophalangeal dislocation

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    Purpose: The present study aimed to examine the dorsal approach to complex MCP joint dislocation and to compare our clinical results with others reported in the literature. Methods: The study retrospectively reviewed the files of patients diagnosed with complex MCP joint dislocation treated in our orthopedics and traumatology clinic between January 2011 and 2022. For all patients, age, gender, affected side, affected finger, injury mechanism, grip strength on the injured side, grip strength in the intact contralateral hand, range of motion of the affected finger, range of motion of the contralateral finger, two-point discrimination, dominant hand and associated bone fractures were recorded. Data analysis used IBM SPSS software, version 22.0 (IBM Corporation, New York, USA). Results: Median follow-up was 11.5 (7–18) years, and mean age 27.6 (18–52) years. Mean joint range of motion was 83.9° (67−100) post-recovery, and 84.2° (65−100) contralaterally, with no significant difference between the two. Mean two-point discrimination was 2.91 (2.5−3.2) cm in the operated finger, and 2.93 (2.6−3.2) cm contralaterally, with no significant difference between the two. There was likewise no significant difference in grip strength: 88.8 (60−107) lbs, versus 91.8 (70−110) lbs contralaterally. Conclusions: The dorsal approach is a simple and reliable means of joint reduction, providing visualization of joint bone surfaces and not requiring exploration of neurovascular structures. Level of Evidence: Therapeutic, Level III. © 2023 SFC
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