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In recent years, there has been an increasing trend towards viewing complex infrastructure systems in a holistic manner, to better understand their behaviour. This paper extends the holism concept to facilitate comprehension of the deterioration of the three bridge components: the deck, superstructure, and substructure. The hypothesis is that these bridge components deteriorate, not in isolation, but collectively as a system of systems, and therefore their deterioration exhibits substantial interdependency. To investigate these interdependencies, this paper uses National Bridge Inventory (NBI) data. The paper explores the efficacy of using a multivariate three-stage least squares (3SLS) model to describe these interdependencies and to quantify the effects of other explanatory factors on the deterioration of these components. The results of the 3SLS model are compared to traditional linear models estimated using ordinary least squares (OLS), to demonstrate the 3SLS model's ability to return more precise estimates of bridge deterioration effects. The results show that the 3SLS model statistically outperforms the OLS models by an average of 104% and 173%, based on root mean square error and mean absolute percentage error, respectively. These results support the hypothesis that bridge components exhibit system-of-systems behavior as their deterioration levels are influenced by the condition of each other. The results also suggest that such holistic nature can be captured using a simultaneous equation model. Improved condition prediction can enhance confidence in agency bridge management functions and result in a more efficient use of limited public resources for infrastructure maintenance and repair. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the effect of diabetes mellitus on lacrimal gland morphology and function. Materials and Methods: The lacrimal glands of rats (n = 6) were removed 8 weeks after the onset of diabetes and processed for electron microscopy. The lacrimal gland of control rats (n = 6) were processed similarly. Lacrimal tissue samples of diabetic rats (n = 12) were also incubated with different concentrations (10-6 - 10-3M) of acetylcholine and noradrenaline to investigate secretagogue-induced peroxidase release. The lacrimal glands of control rats (n = 12) were treated in a similar manner Results: Diabetic rats and their lacrimal glands gained significantly (p < 0.05) less weight compared to age-matched controls. Lacrimal acinar cells of diabetic rat have significantly (p < 0.001) smaller and more homogenous secretory granules compared to age-matched control. Lacrimal glands of diabetic rats contained significantly (p < 0.05) less peroxidase and secrete significantly less quantity (p < 0.05) of the enzyme in response to either acetylcholine or noradrenaline challenge compared to control glands. Conclusions: The results indicate that diabetes is associated with lacrimal gland insufficiency as a result of abnormal acinar morphology and reduced peroxidase content and secretion. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the efficacy of deep intramuscular methylprednisolone (IMMP) in the treatment of recurrent scleritis. Methods: A total of 15 patients with scleritis (12 anterior, 3 pan) underwent IMMP injection deep into the thigh. Thirteen patients were already being treated with oral non-steroidal anti-inflammatory drugs, oral prednisolone, an oral immunosuppressive agent, or a combination of these drugs. A second IMMP injection was given to nine patients, making a total of 24 injections. Follow-up ranged from 4 to 18 months. Results: There was a documented improvement in scleritis after 21/24 (87.3%) injections with a mean duration of improvement of 5.7 months. No patient required the introduction of oral corticosteroid or immunosuppressive agent, and only one patient required an increase in methotrexate to control the disease. No systemic, injection site, or ocular side effects were noted. Conclusions: Deep IMMP is a safe and effective treatment for scleritis. It ensures compliance, avoids the systemic side effects of oral corticosteroids, and is easily repeatable in the outpatient setting. [ABSTRACT FROM AUTHOR]

Purpose: To report bilateral ocular hypertension in association with ocular sarcoidosis. Methods: Case note review of patients with a diagnosis of sarcoidosis-related uveitis. Results: The authors identified 5 patients who fulfilled the diagnostic criteria for ocular sarcoidosis and who had intraocular pressures of > 40 mmHg in each eye. Conclusions: Physicians should be aware of the association of raised intraocular pressure with ocular sarcoidosis. [ABSTRACT FROM AUTHOR]