Structure of a Superhydrophilic Surface: Wet Chemically Prepared Rutile-TiO2(110)(1 × 1).

Surface X-ray diffraction has been employed to quantitatively determine the geometric structure of an X-ray-induced superhydrophilic rutile-TiO2(110)(1 × 1) surface. A scatterer, assumed to be oxygen, is found at a distance of 1.90 ± 0.02 Å above the five-fold-coordinated surface Ti atom, indicating surface hydroxylation. Two more oxygen atoms, situated further from the substrate, are also included to achieve the optimal agreement between experimental and simulated diffraction data. It is concluded that these latter scatterers are from water molecules, surface-localized through hydrogen bonding. Comparing this interfacial structure with previous studies suggests that the superhydophilicity of titania is most likely to be a result of the depletion of surface carbon contamination coupled to extensive surface hydroxylation.

Geometry of α-Cr2O3(0001) as a Function of H2O Partial Pressure.

Surface X-ray diffraction has been employed to elucidate the surface structure of α-Cr2O3(0001) as a function of water partial pressure at room temperature. In ultra high vacuum, following exposure to ∼2000 Langmuir of H2O, the surface is found to be terminated by a partially occupied double layer of chromium atoms. No evidence of adsorbed OH/H2O is found, which is likely due to either adsorption at minority sites, or X-ray induced desorption. At a water partial pressure of ∼30 mbar, a single OH/H2O species is found to be bound atop each surface Cr atom. This adsorption geometry does not agree with that predicted by ab initio calculations, which may be a result of some differences between the experimental conditions and those modeled.

Urban ozone measurements using differential optical absorption spectroscopy.

In order to improve the air quality in Europe the European Commission has issued a number of directives with regard to acceptable levels of a range of gaseous pollutants, which includes ozone. Therefore, monitoring of this compound is necessary to comply with EU legislation, to provide improved pollution warnings for those who are sensitive to air pollutants as well as providing valuable data for environmental planning. Open-path spectroscopic techniques, such as differential optical absorption spectroscopy (DOAS), are ideal for monitoring pollutants because of the advantages they offer over classical methods and point-source analysers. A DOAS system has been installed in Dublin city centre to monitor a range of criteria pollutants including ozone. Observations of urban background ozone concentrations are presented. The measurements are compared with those obtained using a UV point-source analyser and are presented in the context of the current EU directive. The influence of trans-boundary pollution from mainland Europe leading to ozone episodes is also discussed. Observations of high ozone during this measurement campaign coincided with the influx of photochemically polluted air masses which originated over continental Europe. For the analysed time interval, the data suggest that the ground ozone level in Dublin might be significantly influenced by long-range transport from the United Kingdom and continental Europe.

Evaluation of amylase and lipase in the diagnosis of acute pancreatitis.

BACKGROUND: The diagnosis of acute pancreatitis relies heavily on a raised amylase. METHODS: In the present study patients were prospectively categorized, without knowledge of pancreatic enzyme levels, into acute pancreatitis (AP; n = 51), disease controls (n = 35), indeterminate as to pancreatitis (n = 189) or exclusions (non-pancreatitis diseases where amylase may be elevated; n = 53). RESULTS: Enzyme levels were analysed by receiver operator characteristics (ROC) curves, with specificity > 80%. Day 1 serum lipase gave the greatest diagnostic accuracy (area under ROC curve = 0.128; P = 0.041 vs serum amylase). At the calculated diagnostic threshold of 208 U/L, lipase gave a sensitivity of 67% and a specificity of 97%. Other diagnostic thresholds (day 1) were: serum total amylase, 176 U/L (ROC 0.104, sensitivity 45%, specificity 97%), urinary total amylase, 550 U/L (ROC 0.108, sensitivity 62%, specificity 97%) and serum pancreatic isoamylase, 41 U/L (ROC 0.107, sensitivity 63%, specificity 85%). At delayed diagnosis (3 days) no enzyme was superior to lipase. The combination of lipase and amylase did not increase diagnostic accuracy. CONCLUSION: Serum lipase is recommended for diagnosis of AP, both early and late in the disease. Although highly specific when elevated, all pancreatic enzymes have low sensitivity for diagnosis.

Delays in administration of acetylcysteine in paracetamol overdose.

Despite an effective antidote, paracetamol overdose is a frequent cause of fulminant hepatic failure in Ireland and the United Kingdom. Most treatment failures are due to late presentation but some may be related to delayed treatment in hospital. The aim of this study was to investigate delays in treatment in patients presenting to two large Dublin accident and emergency departments. One hundred and seventy seven admissions were recorded over a two year period. The average patient presented 6-8 hours after the overdose and waited another 1.5 to 2 hours for treatment to commence. Treatment was delayed more than 2 hours after presentation in 24/110 (22%) and more than 4 hours in 10/110 (10%). The majority had no adverse sequelae but four patients required ventilation, one haemofiltration and one died. The patient who died presented 35 hours after overdose. This study suggests that delays in treatment of paracetamol overdose are common. Delays of this magnitude may be clinically important in the small minority of patients with significant liver injury. It is possible that oral administration of n-acetylcysteine may reduce delays in treatment.

Perspectives on cancer patient education.

OBJECTIVES: To provide an overview on cancer patient education. DATA SOURCES: Literature related to demographic and health care trends, patient education, health literacy, and cancer patient information needs. CONCLUSIONS: Cancer patients need information related to diagnosis, treatment, side effects, self-care needs, and effects on work and relationships. Planned patient teaching includes a variety of teaching strategies and written materials, and contributes to better patient outcomes. Inadequate health literacy and other barriers present challenges to providing effective patient education. IMPLICATIONS FOR NURSING PRACTICE: More research is warranted in developing assessment tools and effective health education techniques and in measuring outcomes and costs related to patient education. The education needs of cancer patients will not drastically change in the next century. How nurses meet those needs, however, will change as we apply new learning theories and technologies of teaching.