Synthesis and Photocatalytic Activity of Anatase TiO2 Nanoparticles-coated Carbon Nanotubes

A simple and straightforward approach to prepare TiO2-coated carbon nanotubes (CNTs) is presented. Anatase TiO2 nanoparticles (NPs) with the average size ~8 nm were coated on CNTs from peroxo titanic acid (PTA) precursor even at low temperature of 100 °C. We demonstrate the effects of CNTs/TiO2 molar ratio on the adsorption capability and photocatalytic efficiency under UV–visible irradiation. The samples showed not only good optical absorption in visible range, but also great adsorption capacity for methyl orange (MO) dye molecules. These properties facilitated the great enhancement of photocatalytic activity of TiO2 NPs-coated CNTs photocatalysts. The TiO2 NPs-coated CNTs exhibited 2.45 times higher photocatalytic activity for MO degradation than that of pure TiO2

The role of metacognition in self-critical rumination: an investigation in individuals presenting with low self-esteem

Background: No research, to date, has directly investigated the role of metacognition in self-critical rumination and low self-esteem. Aim: To investigate the presence of metacognitive beliefs about self-critical rumination; the goal of self-critical rumination and its stop signal; and the degree of detachment from intrusive self-critical thoughts. Method: Ten individuals reporting both a self-acknowledged tendency to judge themselves critically and having low self-esteem were assessed using metacognitive profiling, a semi-structured interview. Results: All participants endorsed both positive and negative metacognitive beliefs about self-critical rumination. Positive metacognitive beliefs concerned the usefulness of self-critical rumination as a means of improving cognitive performance and enhancing motivation. Negative metacognitive beliefs concerned the uncontrollability of self-critical rumination and its negative impact on mood, motivation and perception of self-worth. The primary goal of engaging in self-critical rumination was to achieve a better or clearer understanding of a given trigger situation or to feel more motivated to resolve it. However, only four participants were able to identify when this goal had been achieved, which was if the trigger situation were not to occur again. Participants unanimously stated that they were either unable to detach from their self-critical thoughts or could do so some of the time with varying degrees of success. More often than not, though, self-critical thoughts were viewed as facts, would rarely be seen as distorted or biased, and could take hours or days to dissipate. Conclusions: These findings provide preliminary evidence that specific facets of metacognition play a role in the escalation and perseveration of self-critical rumination

Data enhancement for co-morbidity measurement among patients referred for sleep diagnostic testing: an observational study

<p>Abstract</p> <p>Background</p> <p>Observational outcome studies of patients with obstructive sleep apnea (OSA) require adjustment for co-morbidity to produce valid results. The aim of this study was to evaluate whether the combination of administrative data and self-reported data provided a more complete estimate of co-morbidity among patients referred for sleep diagnostic testing.</p> <p>Methods</p> <p>A retrospective observational study of 2149 patients referred for sleep diagnostic testing in Calgary, Canada. Self-reported co-morbidity was obtained with a questionnaire; administrative data and validated algorithms (when available) were also used to define the presence of these co-morbid conditions within a two-year period prior to sleep testing.</p> <p>Results</p> <p>Patient self-report of co-morbid conditions had varying levels of agreement with those derived from administrative data, ranging from substantial agreement for diabetes (κ = 0.79) to poor agreement for cardiac arrhythmia (κ = 0.14). The enhanced measure of co-morbidity using either self-report or administrative data had face validity, and provided clinically meaningful trends in the prevalence of co-morbidity among this population.</p> <p>Conclusion</p> <p>An enhanced measure of co-morbidity using self-report and administrative data can provide a more complete measure of the co-morbidity among patients with OSA when agreement between the two sources is poor. This methodology will aid in the adjustment of these coexisting conditions in observational studies in this area.</p

Clinicopathologic Features Associated With Having Four or More Metastatic Axillary Nodes in Breast Cancer Patients With a Positive Sentinel Lymph Node

The survival benefit of a completion axillary lymph node dissection (ALND) in patients after removal of a metastatic sentinel lymph node (SLN) is uncertain and is under study in ongoing clinical trials. The completion ALND remains necessary, however, for the identification of cases with at least four metastatic lymph nodes, in which extended-field locoregional and/or postmastectomy radiation will be recommended. Our goal was evaluate clinicopathologic features that might serve as surrogates for determining which patients with a positive SLN are likely or unlikely to belong to this high-risk subset.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41409/1/10434_2006_Article_9251.pd

Escalating penalties for repeat offenders: a note on the role of information

Optimal law enforcement, Escalating sanctions, Repeat offender, Imperfect information, K42, H23,

Non-chondritic sulphur isotope composition of the terrestrial mantle

International audienceCore-mantle differentiation is the largest event experienced by a growing planet during its early history. Terrestrial core segregation imprinted the residual mantle composition by scavenging siderophile (iron-loving) elements such as tungsten, cobalt and sulphur. Cosmochemical constraints suggest that about 97% of Earth's sulphur should at present reside in the core, which implies that the residual silicate mantle should exhibit fractionated 34S/32S ratios according to the relevant metal-silicate partition coefficients, together with fractionated siderophile element abundances. However, Earth's mantle has long been thought to be both homogeneous and chondritic for 34S/32S, similar to Canyon Diablo troilite, as it is for most siderophile elements. This belief was consistent with a mantle sulphur budget dominated by late-accreted chondritic components. Here we show that the mantle, as sampled by mid-ocean ridge basalts from the south Atlantic ridge, displays heterogeneous 34S/32S ratios, directly correlated to the strontium and neodymium isotope ratios 87Sr/86Sr and 143Nd/144Nd. These isotope trends are compatible with binary mixing between a low-34S/32S ambient mantle and a high-34S/32S recycled component that we infer to be subducted sediments. The depleted end-member is characterized by a significantly negative δ34S of -1.28 +/- 0.33‰ that cannot reach a chondritic value even when surface sulphur (from continents, altered oceanic crust, sediments and oceans) is added. Such a non-chondritic 34S/32S ratio for the silicate Earth could be accounted for by a core-mantle differentiation record in which the core has a 34S/32S ratio slightly higher than that of chondrites (δ34S = +0.07‰). Despite evidence for late-veneer addition of siderophile elements (and therefore sulphur) after core formation, our results imply that the mantle sulphur budget retains fingerprints of core-mantle differentiation