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Core–shell structures with ZnO cores have been widely investigated due to their effectiveness in suppressing surface defects of ZnO nanostructures. As the surface defects are hugely dependent on the synthesis conditions, it is important to understand the interactions between shell material and ZnO with different surface chemistry. Here we produce well-aligned ZnO nanorods using two growth methods, leading to ZnO with different surface chemistries. A thin layer of TiO2 shell is applied via layer-by-layer adsorption method. The core–shell structure is confirmed via high-resolution transmission electron microscopy. The optical properties and chemical states of both bare nanorods and core–shell structures are investigated and compared using photoluminescence (PL) measurement and x-ray photoelectron spectroscopy (XPS). Both PL and XPS results suggest surface defects are passivated by TiO2 shell coating. The shell coating has a stronger effect on ZnO synthesized in OH− rich environment, due to excessive hydroxyl groups provided during synthesis, which remain even after annealing-induced crystallization. [ABSTRACT FROM AUTHOR]

Abstract Background Fatigue among cancer patients has often been reported in the literature; however, great variations have been documented, ranging from 15% to 90%, probably due to the lack of a widely accepted definition and established diagnostic criteria for cancer-related fatigue. The objective of this study was to evaluate the proposed International Statistical Classification of Diseases and Related Health Problems (10th revision) (ICD-10) criteria in a sample of cancer patients from a medical center and a regional teaching hospital in northern Taiwan. More accurate prevalence estimates of CRF may result in improved diagnoses and management of one of the most common symptoms associated with cancer and its treatment. Methods Since self-reporting from patients is the most effective and efficient method to measure fatigue, the ICD-10 criteria for fatigue were used. The ICD-10 criteria questionnaire was translated into Chinese and was approved by experts. Patients were recruited from outpatient palliative and oncology clinics and from palliative and oncology inpatient units. Results Of the 265 cancer patients that were interviewed between 21 October 2008 and 28 October 2009, 228 (86%) reported having at least 2 weeks of fatigue in the past month, and further evaluation with the ICD-10 criteria showed that 132 (49.8%) had cancer-related fatigue. Internal consistency was very good, which was indicated by a Cronbach alpha of 0.843. Conclusion The prevalence of diagnosable CRF in the patients in this sample, of whom most were under palliative treatment, was 49.8%, which was probably somewhat lower than in some of the previous reports that have used less-strict criteria. In addition, among the various criteria of the proposed diagnostic criteria, the most frequently reported symptoms in our sample populations were regarding sleep disturbance and physical factors. Although they will require further replication in other samples, these formal diagnostic criteria can serve as a step toward a common language and a better understanding of the severity range of CRF.

Automatic material handling system (AMHS) is becoming more important in 300 mm wafer fabrication factories (fab). Effective and efficient design and control of AMHS has become more critical particularly in capacity planning. The major concept of the AMHS capacity determination model is to maintain the originally designed optimal production throughput or cycle time of products. In order to maintain fab’s throughput or cycle time of products, WIP (work in process) portfolio of the constraint or the fastest workstation should be kept. Based on this concept, a GI/G/m queuing model based on FCFS (First-come-first-serve) dispatching rule of AMHS is applied to determine the required number of vehicles. Basically, products should be transported to the specific workstation (constraint or fastest workstation) before the workstation finishes the existing process; therefore, sufficient WIP in front of this specific workstation should be kept. Under this condition, the probability that transportation time exceeds product processing time under a certain transportation capacity level can be calculated by the proposed model. Hence, we can get the required capacity of AMHS to achieve the probability target set in advance. Due to the capacity of AMHS can be set according to the acceptable probability of non-exceeding the processing time of the constraint or fastest workstation, the level of WIP in front of this workstation can be kept. It also can be ensured that AMHS will not affect the production performance as well as keep the reasonable investment level. [ABSTRACT FROM PUBLISHER]

Migration and invasion is one of the most important features in tumor metastasis and development. Non-small cell lung cancer (NSCLC) is one of the most common types of cancer globally, and has been linked to air contamination. Evidence indicates that cysteine-rich angiogenic inducer 61 (CYR61) is associated with the migration and invasion of NSCLC. Overexpression of CYR61 protein promotes the migration and the transition of tumor-derived vascular endothelial cells in NSCLC. However, the association between CYR61 and NSCLC remains poorly understood. Lenvatinib is an oral multi-target drug that targets various receptors upon tumor angiogenesis. Dexamethasone is widely approved for combination therapy in patients with NSCLC. In the current study, the expression and function of CYR61 in NSCLC was analyzed during the progression of NSCLC. Inhibitory effects on migration and invasion induced by lenvatinib and dexamethasone were determined by migratory and invasion assays. Migratory pathways of extracellular signal-regulated kinases (ERK) and protein kinase B (AKT) were also investigated by targeting vascular endothelial growth factor (VEGF) and CYR61 via synergistic treatment with transforming growth factor-β1 (TGF-β1) and dexamethasone. Therapeutic outcomes of combined treatment with lenvatinib and dexamethasone were assessed in NSCLC-bearing mice. The results of the present study indicate that cooperative treatment of lenvatinib and dexamethasone significantly inhibited TGF-β1-induced cell migration and suppressed tumor growth (P<0.01). Notably, the results demonstrated that dexamethasone eradicated the promotion effects of TGF-β1 on the AKT/epithelial-mesenchymal transition process and lenvatinib extinguished tumor cell metastasis by targeting VEGF. The results of the current study also demonstrate that dexamethasone suppressed the expression of CAG-I and enhanced expression of matrix metalloproteinase-1. Synergistic treatment for NSCLC was demonstrated to be efficacious. In conclusion, dexamethasone inhibited AKT/ERK phosphorylation and lenvatinib antagonism bound VEGF leading to the limitation of migration and invasion of cancer cells in NSCLC. [ABSTRACT FROM AUTHOR]

Time constraints related issues are unavoidable in wafer fabrications. However, when the lots released from a batch workstation overload the downstream serial workstation the consequences are more serious. Under a time constraints environment, peak workload is a critical problem that seriously hurts the overall performance of the downstream workstation. This work applies a GI/G/m queuing network to develop a capacity planning model for batch-serial processes. By applying this queuing network model, the expected waiting time between batch-serial processes can be estimated. Managers can also determine the capacity through the setting of expected rate of exceeding time constraints. The arrival smoothing of the upstream batch workstation and its effect on the downstream workstation is also analysed. The results show that arrival smoothing can effectively decrease the waiting time on the downstream serial workstation through increasing the upstream number of batch machines and decreasing the batch size. The results also conclude that increasing the number of downstream serial machines is not the only option under the batch-serial process in a time constraint environment. Therefore, an investment function of batch-serial process equipment with time constraints is established in this work that can support managers when making investment decisions. [ABSTRACT FROM AUTHOR]

A time constraint is a queue-time boundary that is set between particular sequential operations to ensure final product yield. These time boundaries, called 'sequential time constraints', can be found in a series of operations on the back-end of wafer fabrication. Wafers exceeding the time constraints are traced through the fabrication process, but generally pass through the remaining processes. Nonetheless, it is a waste of capacity to continue processing wafers with unacceptable yield. Unfortunately, these unacceptable wafers cannot be identified before the wafer acceptance test using the current control policy. This work proposes a control rule for two-level time constraints with capacity planning methodology under this rule. Wafers exceeding the lower time constraints will be treated as normal wafers; however, once wafers exceed the upper time constraint, they will be scrapped immediately. In the capacity planning model, a GI/G/m queuing network is applied to determine the required number of machines. By pre-setting target yields, the rates of wafers being marked or scrapped can be controlled. Furthermore, a novel scheme-regarding machine failures as irregular customers-is introduced to describe the effect of service interruptions. The results show that the proposed control rule and capacity planning model can more effectively resolve the issues of sequential time constraints. Moreover, the results of the analysis indicate that the current capacity expansion policy of the semiconductor industry should be re-examined. [ABSTRACT FROM AUTHOR]

Foundry companies are very concerned about fully utilizing equipment and increasing productivity because of the rapid depreciation and large investments made in equipment. Factory output is limited by its bottleneck machine. If a discrepancy exists between the planned and actual product mix, a new machine will become the bottleneck and will have a strong impact on the capacity. All famous foundry companies, such as TSMC, UMC, and others, implement backup solutions to such problems. However, the level of protective capacity at the non-bottleneck workstations strongly affects production performance. Therefore, the backup quantity should be well managed. Accordingly, a backup capacity determination model is presented in two parts: the Backup Capacity Determination Model (BCDM) and the Performance Evaluation Model (PEM). The concept of protective capacity is applied to determine the backup capacity in the BCDM. The determination of protective capacity is based on the statistical fluctuation of factors that include machine downtime and unreasonable queuing time in front of the non-bottleneck workstations. The PEM applies queuing theory and Little's Law to evaluate the effects of the backup capacity exceeding the backup capacity on throughput, work in process and the cycle time of the backup factory. A backup capacity determination model provides important information, so that managers have access to a sufficient and reliable reference when confronted with a problem that involves backup capacity. [ABSTRACT FROM AUTHOR]