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Background The effective management of chronic tuberculous empyema requires an evacuation of pus and a re-expansion of the lung or an obliteration of the empyema space such as closed thoracostomy, decortication, or open window thoracostomy (OWT) followed by intrathoracic muscular transposition (IMT). However, the most effective management of chronic tuberculous empyema is still debatable. Methods From June 1999 to July 2010, 18 patients with chronic tuberculous empyema who underwent OWT and/or IMT were enrolled in this study. The causes of empyema, and methods and outcomes of treatment were retrospectively reviewed. The success rate of IMT was investigated to evaluate the efficacy. Results Mean patient age was 54.3 ± 14.9 years and 16 patients were male. Depending on operative methods, three groups were divided: OWT only (n = 4); two-stage operation as OWT followed by IMT (n = 7); and one-stage operation as OWT with IMT simultaneously (n = 7). Of 14 patients who underwent IMT, 13 patients successfully recovered from empyema and bronchopleural fistula (BPF) (success rate, 92.86%), but one patient developed a secondary bacterial infection. There was no operative mortality. Conclusion This study suggests that IMT may be an effective option to control infection or BPF in chronic tuberculous empyema. [ABSTRACT FROM AUTHOR]

Pulmonary extrauterine epithelioid trophoblastic tumors (ETTs) are extremely rare. A 26-year-old nonsmoking woman with a history of a suspected subclinical miscarriage presented with a large mass in the right lower lobe that was confirmed to be a pulmonary extrauterine ETT using immunohistochemical stains. When a nonsmoking fertile woman presents with a pulmonary mass and an elevated serum β-human chorionic gonadotrophin in the absence of gynecologic disease, pulmonary extrauterine ETT should be considered. [ABSTRACT FROM AUTHOR]

The article details a study which evaluated the performance of confirmatory interferon-γ release assays (IGRAs) in addition to tuberculin skin tests (TSTs) in high school students with TST-positive (TST+) results who have had contact with another student who had tuberculosis (TB). The study found that the addition of confirmatory IGRA for TST+ TB patients can effectively focus latent TB infection (LTBI) treatment targeting.

This paper presents a model for integrating inventory replenishment and delivery planning in a two-level supply chain consisting of a supplier and a retailer. The supplier is authorized to manage the inventory level of the retailer by using the information on demands from final customers and the inventory level of the retailer. The problem considered here is to determine order-up-to levels of the supplier and the retailer simultaneously for the objective of minimizing the expected long-run average cost, which is composed of replenishment cost at the supplier, delivery cost to the retailer, and inventory holding costs at both members. We develop a renewal theoretic optimization model for a case of compound Poisson demands with distribution-free order quantities and present an approximation method for obtaining a solution of the problem. In addition, a closed-form solution is derived for the problem with a special case of compound Poisson demands, in which demand quantities follow an exponential distribution. A series of simulation tests show that the solutions obtained from the approximated cost functions are reasonably good. [ABSTRACT FROM AUTHOR]

This paper focuses on the problem of scheduling wafer lots on diffusion workstations in a semiconductor wafer fabrication facility. In a diffusion workstation, there are multiple identical machines, and each of them can process a (limited) number of wafer lots at a time. Wafer lots can be classified into several product families, and wafer lots that belong to the same product family can be processed together as a batch. Processing times and setup times for wafer lots of the same product family are the same, but ready times of the wafer lots (at the diffusion workstation) may be different. We present several heuristic algorithms for the problem with the objective of minimizing total tardiness. For evaluation of performance of the suggested algorithms, a series of computational experiments is performed on randomly generated test problems. Results show that the suggested algorithms perform better than algorithms currently used in practice. [ABSTRACT FROM AUTHOR]

This paper focuses on a lot-order assignment problem, called the pegging problem, in a semiconductor wafer fabrication facility. Pegging is a process of assigning wafer lots to orders for wafers. We consider two types of pegging strategies: hard pegging strategy, under which the lot-order assignment is not changed once lots are assigned to orders; and soft pegging strategy, under which the lot-order assignment can be changed during the production period. For the soft pegging strategy, we develop three operational policies and three algorithms for the pegging problem of assigning lots to orders with the objective of minimizing total tardiness of the orders. To evaluate performance of the suggested policies and algorithms, we perform simulation experiments using real factory data as well as randomly generated data sets. Results of the simulation tests show that the repegging policies and the algorithms operated under the soft pegging strategy give better results than the hard pegging strategy. [ABSTRACT FROM AUTHOR]

This paper presents a real-time scheduling methodology in a semiconductor wafer fab that produces multiple product types with different due dates. In the suggested real-time scheduling method, lot scheduling rules and batch scheduling rules are selected from sets of candidate rules based on information obtained from discrete event simulation. Since a rule combination that gives the best performance may vary according to the states of the fab, a selected rule combination is employed for a certain period of time and then a new combination is selected and employed. Since multiple simulation runs should be made in the simulation-based real-time scheduling (SBRTS) method, it may take excessively long computation time to react to unexpected events. To reduce response time, we suggest three techniques for accelerating rule comparison. We test these techniques as well as other operational policies that can be used in the SBRTS method through computational experiments on a number of test problems. [ABSTRACT FROM AUTHOR]

The loading problem in a Flexible Manufacturing System (FMS) involves allocating operations and associated cutting tools to machines for a given set of parts. There may be different environments for the loading problem that result from three ways of grouping machines in an FMS, i.e., no grouping, partial grouping, and total grouping. Unlike most previous studies on the loading problem for the configurations of no grouping and total grouping, this paper focuses on the loading problem resulting from partial grouping, in which each machine is tooled differently but each operation can be processed by one or more machines. Two types of heuristic algorithms are suggested for the loading problem with the objective of minimizing the maximum workload of the machines. Performances of the suggested loading algorithms are tested on randomly generated test problems and the results show that the suggested algorithms perform better than existing ones. In addition, it is found from simulation experiments that loading plans from partial grouping give significantly better performance than those from total grouping. [ABSTRACT FROM AUTHOR]

This note presents an efficient approximation method to evaluate the performance of tree-structured Assembly/Disassembly (AD) systems in which each station consists of multiple identical machines. It is assumed that the times to failure, times to repair, and processing times are exponentially distributed and the capacities of the buffers are finite. The method transforms an AD system with parallel machines in each station to an (approximately) equivalent AD system with a single machine in each station. After the transformation, a decomposition algorithm is used to analyze the performance of the transformed system. The results of computational experiments show that the suggested method gives good estimates in a short time. [ABSTRACT FROM AUTHOR]

Although osteomyelitis is a very rare complication of Bacillus Calmette-Guérin (BCG) vaccination, sternal osteomyelitis as a late complication of BCG vaccination diagnosed by polymerase chain reaction (PCR) in a child is described. We might consider BCG osteomyelitis in the case of osteomyelitis without bacterial isolation within a year after BCG vaccination, the absence of pulmonary foci, and a contact to the patient with tuberculosis. [ABSTRACT FROM AUTHOR]

We report a case of a symptomatic angioleiomyoma in the left posterior mediastinum. A 66-year-old woman presented with left back and flank pain for 6 months. Chest computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well-circumscribed 4.3 cm round mass. The mass was initially diagnosed as nerve sheath tumor, because of her symptoms and its close location to the sympathetic trunk and intercostal nerve. It was uneventfully removed through video-assisted thoracoscopic surgery. The pathology revealed an angioleiomyoma. [ABSTRACT FROM AUTHOR]