Ultrathin TiN Epitaxial Films as Transparent Conductive Electrodes.

Titanium nitride (TiN), a transition-metal compound with tight covalent Ti-N bonding, has a high melting temperature and superior mechanical and chemical stabilities compared to noble metals. With a reduction in thickness, the optical transmittance of TiN films can be drastically increased, and in combination with its excellent electrical conductivity, the ultrathin and continuous TiN film can be considered as an ideal alternative of the metal oxide electrodes. However, the deposition of ultrathin and continuous metallic layer with a smooth surface morphology is a major challenge for typical deposition methods such as thermal evaporation or reactive sputtering. In particular, defects mainly related with oxygen contents and surface scattering can significantly limit the performance of ultrathin TiN films. In this work, ultrathin TiN films with 2-10 nm in thickness are grown by using the nitrogen plasma-assisted molecular-beam epitaxy (MBE) method in an ultrahigh vacuum environment. Excellent surface morphology with a root-mean-square roughness of ≤0.12 nm and a high optical transparency of 75% over the whole visible regime are achieved for ultrathin TiN epitaxial films. The dielectric properties determined by the spectroscopic ellipsometry and the electrical properties measured by the terahertz spectroscopy and the Hall effect method reveal that the percolation thickness of the TiN epitaxial film is less than 2.4 nm and its electrical conductivity is higher than 1.1 × 104 Ω-1 cm-1. These features make MBE-grown ultrathin TiN epitaxial films a good candidate for robust, low cost, and large-area transparent conductive electrodes.

Block-Based Connected-Component Labeling Algorithm Using Binary Decision Trees.

In this paper, we propose a fast labeling algorithm based on block-based concepts. Because the number of memory access points directly affects the time consumption of the labeling algorithms, the aim of the proposed algorithm is to minimize neighborhood operations. Our algorithm utilizes a block-based view and correlates a raster scan to select the necessary pixels generated by a block-based scan mask. We analyze the advantages of a sequential raster scan for the block-based scan mask, and integrate the block-connected relationships using two different procedures with binary decision trees to reduce unnecessary memory access. This greatly simplifies the pixel locations of the block-based scan mask. Furthermore, our algorithm significantly reduces the number of leaf nodes and depth levels required in the binary decision tree. We analyze the labeling performance of the proposed algorithm alongside that of other labeling algorithms using high-resolution images and foreground images. The experimental results from synthetic and real image datasets demonstrate that the proposed algorithm is faster than other methods.

An analysis of surgical outcomes in patients aged 80 years and older.

OBJECTIVES: Elderly patients (aged ≥ 80 years) undergo an increasing number of operations. Elderly patients undergoing operations usually develop more postoperative complications and have poorer outcomes. The aim of this study is to identify the relative importance between preoperative and intraoperative variables to predict adverse postoperative outcomes in these patients. METHODS: We retrospectively analyzed the records of 404 patients (aged ≥ 80 years and underwent a noncardiac surgery) collected from the quality assurance database in our department. We reviewed the patients' preoperative and intraoperative variables as well as postoperative complications and outcomes. Odds ratios of risk factors were then calculated by univariate and multivariate analyses. In addition, hazard ratios of incidence of discharge and mortality rates were analyzed. RESULTS: Overall, 26.4% of patients developed one or more postoperative complications, and the in-hospital mortality rate was 6.7%. The majority of these patients had pre-existing cardiovascular disorders such as hypertension (47.5%). Respiratory complication was the most common postoperative complication (12.9%). Multivariate analysis showed male sex, anesthesia method, and colloid infusion were risk factors for increased respiratory complication. Our results showed that patients who developed different kinds of postoperative complications had a different level of risks associated with prolonged hospital stay and mortality. CONCLUSION: Patients over the age of 80 years, of male sex, under general anesthesia, and receiving colloid infusion were at a higher risk of developing respiratory complications. Postoperative respiratory complications occurred in most of the geriatric surgical patients. Efforts to improve the surgical outcomes must include measures to minimize in-hospital complications. Detailed evaluation and better communicating the aforementioned risk factors to these patients are suggested for improving anesthesia quality and surgical outcomes.

Predictive risk index and prognosis of postoperative reintubation after planned extubation during general anesthesia: a single-center retrospective case-controlled study in Taiwan from 2005 to 2009.

OBJECTIVES: Postoperative reintubation after planned extubation (RAP) following general anesthesia is a major anesthetic morbidity. A previous study on RAP identified the various risk factors for RAP, including chronic obstructive pulmonary disease (COPD), pneumonia, systemic inflammatory response syndrome (SIRS), and airway surgery. However, the prognosis and predictive risk index of RAP were not investigated. METHODS: Data on surgical patients who were reintubated after planned extubation at the end of surgery between January 1, 2005 and December 31, 2009 were retrospectively sorted out from the quality assurance database of the Department of Anesthesiology, Chang Gung Memorial Hospital. Risk factors and prognosis of RAP cases were compared with the control group (successful planned extubation) using descriptive statistics and logistic regression. The RAP predictive risk index was developed from multivariate logistic regression and the predictive accuracy was evaluated by goodness-of-fit test. RESULTS: Of the 227,876 patients who were subjected to endotracheal intubation for general anesthesia, 130 (0.06%) sustained postoperative RAP. The control group consisted of 390 patients who were randomly selected from those who underwent endotracheal intubation without RAP. A total of 30 variables, including demographic, operative, anesthetic data, and prognosis were analyzed. We found that significant risk factors for RAP included COPD (odds ratio: 4.30), pneumonia (odds ratio: 6.60), ascites (odds ratio: 4.86), SIRS (odds ratio: 7.52), hypothermia (body temperature <35°C; odds ratio: 2.45), rocuronium as muscle relaxant (odds ratio: 1.90), inexperienced anesthetic service (odds ratio: 3.44), and airway surgery (odds ratio: 4.34). An RAP predictive risk index was developed and the predictive accuracy was confirmed by goodness-of-fit test as excellent discrimination (c statistic: 0.873). RAP significantly increased postoperative stay in hospital (odds ratio: 2.46) and intensive care unit, as well as tracheostomy and mortality (odds ratio: 58.52). CONCLUSION: The RAP predictive risk index included higher American Society of Anesthesiologists classification, conscious disturbance, COPD, pneumonia, SIRS, room air SpO2 <95%, hypothermia, airway surgery, and head and neck surgeries. The RAP predictive risk index provides us an opportunity to take preventive measures including renewal of risk-reduction protocols for high-risk patients.