An Optimization-Based Computational Procedure for Retrofit of Refinery Water Network Systems Incorporating Water Reuse, Regeneration, and Recycle

Water is a key element for the normal functioning of refineries and petrochemical plants in the hydrocarbon processing industry. Scarcities in freshwater supply and increasingly stringent rules on wastewater discharges have emerged as issues of major concern in our time. Water has become an increasingly crucial resource to industrial plants due to increased requirements in operating efficiency and optimization, to avoid high demand of water, and the drive for sustainable development that may result in plants being vulnerable to interruptions in water supply and to water shortages in the future. It is a well-acknowledged fact that cost of water is low but its value is high, and that there is increased regulatory requirements for zero discharge from process plants. In line with these developments, this work has been undertaken with the goal of formulating and solving a mathematical optimization model for the optimal design of an integrated water network system for a typical oil refinery via combined knowledge of engineering heuristics and mathematical programming. The integrated model explicitly considers the incorporation of water minimization approaches and strategies that consist of the potential for water reuse, regeneration, and recycle (W3R), with the objective of minimizing freshwater consumption and wastewater flows while complying to the maximum allowable contaminant concentrations where it is concerned. The stipulated objective directly corresponds to minimizing the associated capital and operating costs of the facility, although cost is not explicitly considered in this work. The methodology includes data collection on flowrates and contaminant concentrations and the subsequent step of data reconciliation on the water balances. Next, a superstructure embedding all feasible alternatives for the implementation of the potential W3R opportunities are developed. A nonlinear programming (NLP) model is then formulated based on the superstructure with the addition of constraints on the maximum allowable contaminant concentrations to meet regulatory discharge requirements as well as for the evaluation of W3R opportunities. Computational studies are performed on the NLP model using GAMS algebraic modeling platform on an industrially-significant problem representative of industrial scale with six contaminants considered. The satisfactory numerical results show that our proposed approach is a promising tool to aid decision-making in the retrofit of refinery water network systems

The morphology of diaphragmatic defects in hepatic hydrothorax: Thoracoscopic finding

BackgroundUntil now, the pathophysiology of hepatic hydrothorax has been moot. We discuss (on the basis of gross videothoracoscopy findings in 11 cases and the literature) the pathogenesis and clinical presentation of this complex condition.MethodsWe prospectively studied 11 patients (age, 31–73 years; 6 men and 5 women) with refractory hepatic hydrothorax (Child-Pugh class B-C) who underwent thoracoscopic repair of diaphragmatic defects. The diaphragmatic defects were examined intraoperatively.ResultsThe diaphragmatic defects stemming from hepatic hydrothorax were classified into 4 morphologic types: type I, no obvious defect (1 patient); type II, blebs lying on the diaphragm (4 patients); type III, broken defects (fenestrations) in the diaphragm (8 patients); and type IV, multiple gaps in the diaphragm (1 patient). The type of diaphragmatic defect did not correlate with the volume occupied by the pleural effusion in the preoperative chest radiograms.ConclusionsThe finding of this study allowed hepatic hydrothorax pathophysiology to be directly visualized, and further studies concerning the treatment of hepatic hydrothorax might be based on these mechanisms

DNA methylation subgroups and the CpG island methylator phenotype in gastric cancer: A comprehensive profiling approach

10.1186/1471-230X-14-55BMC Gastroenterology141-BGMA

18 Years Surgical Experience With Mediastinal Mature Teratoma

Few studies have examined the surgical outcomes of mediastinal mature teratoma in Taiwan. In the present study, the clinicopathological characteristics of mature teratoma and their impact on surgical outcome were analyzed. Methods: From 1988 to 2005, 57 cases of mediastinal mature teratoma were reviewed. We collected and analyzed data about patient age, sex, symptoms, blood sugar, pulmonary function, diagnosis, tumor size, histopathological features, operative methods, operative time, tumor adhesion, blood loss, ventilator requirement, intensive care unit stay, chest tube requirement, and postoperative hospital stay. Results: There were 18 male and 39 female patients with a median age of 27 years. Forty-three patients received conventional open surgery, whereas 14 received video-assisted thoracoscopic surgery. The patients in the thoracoscopic group had a decreased operative time (106.4 ± 35.7 min vs. 205.4 ± 75.7 min, p = 0.038), fewer ventilator days (0.2 ± 0.4 vs. 0.5 ± 0.8, p = 0.034), and a shorter stay in the intensive care unit (0.6 ± 0.8 days vs. 1.5 ± 1.4 days, p = 0.030). Pancreatic tissue was identified in 21 of 57 tumors (36.8%). The patients with tumors that contained pancreatic tissue had more presenting symptoms and complicated surgery than those whose tumors were without pancreatic tissue (76.2% vs. 33.3%, p = 0.002, and 42.9% vs. 11.1%, p = 0.008). The patients with symptoms had a higher incidence of complicated surgery than those without (39.3% vs. 6.9%, p = 0.004). Conclusion: Mediastinal mature teratoma commonly occurs in young women. Thoracoscopic surgery is a feasible technique for mediastinal mature teratoma resection if no dense adhesions are found during preoperative assessment. The presence of symptoms might be a relative contraindication for thoracoscopic teratoma resection because of its association with surgical complications

The ability of LCRMP-1 to promote cancer invasion by enhancing filopodia formation is antagonized by CRMP-1

Metastasis is a predominant cause of death in patients with cancer. It is a complex multistep process that needs to be better understood if we are to develop new approaches to managing tumor metastasis. Tumor cell invasion of the local stroma is suppressed by collapsin response mediator protein-1 (CRMP-1). Recently, we identified a long isoform of CRMP-1 (LCRMP-1), expression of which correlates with cancer cell invasiveness and poor clinical outcome in patients with non-small-cell lung cancer (NSCLC). Here, we report that LCRMP-1 overexpression in noninvasive human cell lines enhanced filopodia formation, cancer cell migration, and invasion via stabilization of actin. This effect required a highly conserved N-terminal region of LCRMP-1 as well as the WASP family verprolin-homologous protein-1/actin nucleation pathway (WAVE-1/actin nucleation pathway). Furthermore, LCRMP-1 appeared to act downstream of Cdc42, a Rho family protein known to be involved in actin rearrangement. In addition, LCRMP-1 associated with CRMP-1, which downregulated cancer cell metastasis by interrupting the association of LCRMP-1 and WAVE-1. Finally, we found that high-level expression of LCRMP-1 and low-level expression of CRMP-1 were associated with lymph node metastasis and poor survival in patients with NSCLC. In sum, we show that LCRMP-1 and CRMP-1 have opposing functions in regulating cancer cell invasion and metastasis and propose that this pathway may serve as a potential anticancer target