181 research outputs found
Critical analysis of self-doping and water-soluble n-type organic semiconductors: structures and mechanisms
Self-doping organic semiconductors provide a promising route to avoid instabilities and morphological issues associated with molecular n-type dopants. Structural characterization of a naphthalenetetracarboxylic diimide (NDI) semiconductor covalently bound to an ammonium hydroxide group is presented. The dopant precursor was found to be the product of an unexpected base catalyzed hydrolysis, which was reversible. The reversible hydrolysis had profound consequences on the chemical composition, morphology, and electronic performance of the doped films. In addition, we investigated the degradation mechanism of the quaternary ammonium group and the subsequent doping of NDI. These findings reveal that the products of more than one chemical reaction during processing of films must be considered when utilizing this promising class of water-soluble semiconductors
Secondary Eclipse Photometry of WASP-4b with Warm Spitzer
We present photometry of the giant extrasolar planet WASP-4b at 3.6 and 4.5
micron taken with the Infrared Array Camera on board the Spitzer Space
Telescope as part of Spitzer's extended warm mission. We find secondary eclipse
depths of 0.319+/-0.031% and 0.343+/-0.027% for the 3.6 and 4.5 micron bands,
respectively and show model emission spectra and pressure-temperature profiles
for the planetary atmosphere. These eclipse depths are well fit by model
emission spectra with water and other molecules in absorption, similar to those
used for TrES-3 and HD 189733b. Depending on our choice of model, these results
indicate that this planet has either a weak dayside temperature inversion or no
inversion at all. The absence of a strong thermal inversion on this highly
irradiated planet is contrary to the idea that highly irradiated planets are
expected to have inversions, perhaps due the presence of an unknown absorber in
the upper atmosphere. This result might be explained by the modestly enhanced
activity level of WASP-4b's G7V host star, which could increase the amount of
UV flux received by the planet, therefore reducing the abundance of the unknown
stratospheric absorber in the planetary atmosphere as suggested in Knutson et
al. (2010). We also find no evidence for an offset in the timing of the
secondary eclipse and place a 2 sigma upper limit on |ecos(omega)| of 0.0024,
which constrains the range of tidal heating models that could explain this
planet's inflated radius.Comment: 8 pages, 7 figures (some in color), accepted for publication in Ap
Credibility and adjustment: gold standards versus currency boards
It is often maintained that currency boards (CBs) and gold standards (GSs) are alike in that they are stringent monetary rules, the two basic features of which are high credibility of monetary authorities and the existence of automatic adjustment (non discretionary) mechanism. This article includes a comparative analysis of these two types of regimes both from the perspective of the sources and mechanisms of generating confidence and credibility, and the elements of operation of the automatic adjustment mechanism. Confidence under the GS is endogenously driven, whereas it is exogenously determined under the CB. CB is a much more asymmetric regime than GS (the adjustment is much to the detriment of peripheral countries) although asymmetry is a typical feature of any monetary regime. The lack of credibility is typical for peripheral countries and cannot be overcome completely even by “hard” monetary regimes.http://deepblue.lib.umich.edu/bitstream/2027.42/40078/3/wp692.pd
The role of a pseudocapsula in thymic epithelial tumors: outcome and correlation with established prognostic parameters. Results of a 20-year single centre retrospective analysis
<p>Abstract</p> <p>Background</p> <p>Treatment of thymoma is often based on observation of only a few patients. Surgical resection is considered to be the most important step. Role of a pseudocapsula for surgery, its clinical significance and outcome compared with established prognostic parameters is discussed which has not been reported so far.</p> <p>Methods</p> <p>84 patients with thymoma underwent resection and analysis was carried out for clinical features, prognostic factors and long-term survival.</p> <p>Results</p> <p>Fifteen patients were classified in WHO subgroup A, 21 in AB, 29 in B and 19 patients in C. Forty two patients were classified in Masaoka stage I, 19 stage II, 9 stage III and 14 stage IV. Encapsulated thymoma was seen in 40, incomplete or missing capsula in 44 patients. In 71 complete resections, local recurrence was 5%. 5-year survival was 88.1%. Thymomas with pseudocapsula showed a significant better survival (94.9% vs. 61.1%, respectively) (p = 0.001) and was correlated with the absence of nodal or distant metastasis (p = 0.04 and 0.001, respectively). Presence of pseudocapsula as well as the Masaoka and WHO classification, and R-status were of prognostic significance. R-status and Masaoka stage appeared to be of independent prognostic significance in multivariate analysis.</p> <p>Conclusion</p> <p>Intraoperative presence of an encapsulated tumor is a good technical marker for the surgeon to evaluate resectability and estimate prognosis. Although the presence of a capsula is of strong significance in the univariate analysis, it failed in the multivariate analysis due to its correlation with clinical Masaoka stage. Masaoka stage has a stronger relevance than WHO classification to determinate long-term outcome.</p
Trends in Depression and Antidepressant Prescribing in Children and Adolescents: A Cohort Study in The Health Improvement Network (THIN)
In 2003, the Committee on Safety of Medicines (CSM) advised against treatment with selective serotonin reuptake inhibitors (SSRIs) other than fluoxetine in children, due to a possible increased risk of suicidal behaviour. This study examined the effects of this safety warning on general practitioners' depression diagnosing and prescription behaviour in children
Chapter 9 Moral Responsibility and the Justification of Policies to Preserve Antimicrobial Effectiveness
Restrictive policies that limit antimicrobial consumption, including therapeutically
justified use, might be necessary to tackle the problem of antimicrobial
resistance. We argue that such policies would be ethically justified when forgoing
antimicrobials constitutes a form of easy rescue for an individual. These are cases
of mild and self-limiting infections in otherwise healthy patients whose overall
health is not significantly compromised by the infection. In such cases, restrictive
policies would be ethically justified because they would coerce individuals into fulfilling
a moral obligation they independently have. However, to ensure that such
justification is the strongest possible, states also have the responsibility to ensure
that forgoing antimicrobials is as easy as possible for patients by implementing
adequate compensation measures
Candida bracarensis: Evaluation of virulence factors and its tolerance to Amphotericin B and Fluconazole
Candida bracarensis is an uncommon Candida species found during an epidemiological study of candidiasis performed in Braga, Portugal. Initially, it was identified as C. glabrata, but recently detailed analyses pointed out their differences. So, little information is still available about C. bracarensis virulence factors and antifungal susceptibilities. Therefore, the main goal of this work is to evaluate the ability of C. bracarensis to form biofilms, to produce hydrolytic enzymes (proteases, phospholipases and hemolysins), as well as its susceptibility to amphotericin B and fluconazole. It was shown, for the first time, that all C. bracarensis strains were able to form biofilms and display proteinase and hemolytic activities. Moreover, although planktonic cells presented antifungal susceptibility, amphotericin B and fluconazole were unable to inhibit biofilm formation and eradicate pre-formed biofilms. Due to the propensity of C. bracarensis to display antifungal resistance and virulence attributes, the control of these emerging pathogens is recommended.This work was supported by the projects PTDC/SAU-MIC/119069/2010, PEst-OE/EQB/LA0023/2013, from Fundação para a Ciência e Tecnologia (FCT), Portugal and ‘‘BioHealth—Biotechnology and Bioengineering approaches to improve health quality’’, Ref. NORTE-07-0124FEDER-000027, co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. The authors also acknowledge the project ‘‘Consolidating Research Expertise and Resources on Cellular and Molecular Biotechnology at CEB/IBB’’, Ref. FCOMP-01-0124-FEDER027462
Promoting optimal parenting and children’s mental health : a preliminary evaluation of the How-to Parenting Program
Parenting quality is widely accepted as a primary predictor of children’s mental health. The present study examined the effectiveness of a parenting program in fostering optimal parenting and child mental health. The selected program was How to talk so kids will listen & listen so kids will talk (How-to Parenting Program). This program was selected because its content corresponds closely to what the parenting style literature suggests is optimal parenting (i.e., includes structure, affiliation and autonomy support). Eleven groups of six to twelve parents were conducted in 7 local grade schools. The program, offered by two trained leaders, consisted of eight weekly sessions and taught a total of 30 skills. A total of 82 parents completed questionnaires both prior to and after the program. Participants’ children between eight and 12 years old (N = 44) completed questionnaires at school, at both assessment points. Repeated measures ANOVAs using parent reports indicated that structure, affiliation and autonomy support were increased after the program, compared to baseline. The level of child internalizing and externalizing problems also decreased significantly. Importantly, children reports confirmed that parental autonomy support increased from pre to post-test and child-reported well-being improved as well. The preliminary evidence from this pre-test versus post-test repeated measures design suggests that the How-to Parenting Program is effective in improving parenting style and in promoting children’s mental health and that future evaluation research examining the potential of this program is warranted
Evidence of Segregated Spawning in a Single Marine Fish Stock: Sympatric Divergence of Ecotypes in Icelandic Cod?
There is increasing recognition of intraspecific diversity and population structure within marine fish species, yet there is little direct evidence of the isolating mechanisms that maintain it or documentation of its ecological extent. We analyzed depth and temperature histories collected by electronic data storage tags retrieved from 104 Atlantic cod at liberty ≥1 year to evaluate a possible isolating mechanisms maintaining population structure within the Icelandic cod stock. This stock consists of two distinct behavioral types, resident coastal cod and migratory frontal cod, each occurring within two geographically distinct populations. Despite being captured together on the same spawning grounds, we show the behavioral types seem reproductively isolated by fine-scale differences in spawning habitat selection, primarily depth. Additionally, the different groups occupied distinct seasonal thermal and bathymetric niches that generally demonstrated low levels of overlap throughout the year. Our results indicate that isolating mechanisms, such as differential habitat selection during spawning, might contribute to maintaining diversity and fine-scale population structure in broadcast-spawning marine fishes
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