734 research outputs found

    Robust surface electronic properties of topological insulators: Bi2Te3 films grown by molecular beam epitaxy

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    The surface electronic properties of the important topological insulator Bi2Te3 are shown to be robust under an extended surface preparation procedure which includes exposure to atmosphere and subsequent cleaning and recrystallization by an optimized in-situ sputter-anneal procedure under ultra high vacuum conditions. Clear Dirac-cone features are displayed in high-resolution angle-resolved photoemission spectra from the resulting samples, indicating remarkable insensitivity of the topological surface state to cleaning-induced surface roughness.Comment: 3 pages, 3 figure

    Application of Respondent Driven Sampling to Collect Baseline Data on FSWs and MSM for HIV Risk Reduction Interventions in Two Urban Centres in Papua New Guinea

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    The need to obtain unbiased information among hardā€“to-reach and hidden populations for behavioural and biological surveillance, epidemiological studies, and intervention program evaluations has led researchers to search for a suitable sampling method. One method that has been tested among IDU and MSM recently is respondent-driven sampling (RDS). We used RDS to conduct a behavioural survey among FSWs and MSM in two urban centres in Papua New Guinea (PNG). In this paper we present the lessons learned implementing RDS in a developing country setting. We also present comparisons of RDSAT-adjusted versus unadjusted crude estimates of some key socio-demographic indicators as well as comparisons between the estimates from RDS and a hypothetical timeā€“location sample (TLS). Overall, the use of RDS among the MSM and FSWs in PNG had numerous advantages in terms of collecting a required sample size in a short time period, minimizing costs and maximising security for staff and respondents. Although there were a few problems these were easily remedied and we would recommend RDS for other similar studies in PNG and other developing countries

    Gene-expression of metastasized versus non-metastasized primary head and neck squamous cell carcinomas: A pathway-based analysis

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    Background: Regional lymph node metastasis is an important prognostic factor in head and neck squamous cell carcinoma (HNSCC) and plays a decisive role in the choice of treatment. Here, we present an independent gene expression validation study of metastasized versus non-metastasized HNSCC. Methods: We used a dataset recently published by Roepman et al. as reference dataset and an independent gene expression dataset of 11 metastasized and 11 non-metastasized HNSCC tumors as validation dataset. Reference and validation studies were performed on different microarray platforms with different probe sets and probe content. In addition to a supervised gene-based analysis, a supervised pathway-based analysis was performed, evaluating differences in gene expression for predefined tumorigenesis- and metastasis related gene sets. Results: The gene-based analysis showed 26 significant differentially expressed genes in the reference dataset, 21 of which were present on the microarray platform used in the validation study. 7 of these genes appeared to be significantly expressed in the validation dataset, but failed to pass the correction for multiple testing. The pathway-based analysis revealed 23 significant differentially expressed gene sets, 7 of which were statistically validated. These gene sets are involved in extracellular matrix remodeling (MMPs, MMP regulating pathways and the uPA system), hypoxia and angiogenesis (HIF1Ī± regulated angiogenic factors and HIF1Ī± regulated invasion). Conclusion: Pathways that are differentially expressed between metastasized and non-metastasized HNSCC are involved in the processes of extracellular matrix remodeling, hypoxia and angiogenesis. A supervised pathway-based analysis enhances the understanding of the biological context of the results, the comparability of results across different microarray studies, and reduces multiple testing problems by focusing on a limited number of pathways of interest instead of analyzing the large number of probes available on the microarray

    Severe neonatal enterovirus infection in twins with different outcomes:A case report

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    Enteroviruses are among the most common causes of acute viral illness worldwide, and in neonates, the clinical course of these infections is heterogeneous. Severe complications, such as myocarditis, are associated with high mortality rates. In this case report, we present the clinical course of premature twins born at 35 weeks of gestational age, suffering from a severe neonatal enterovirus infection with cardiac involvement, which proved fatal in one of the twins. This course led to prompt identification in the other twin and facilitated timely transfer to a neonatal intensive care unit with neonatal hemodynamic expertise, and facilitated the timely transfer to a neonatal intensive care nit with hemodynamic expertise and immediate availability of AZCMO would it have been indicated. Early supportive therapy in the other twin contributed to a positive outcome. Therefore, we emphasize the importance of early recognition in averting adverse consequences. As a recommendation, we propose routine screening of enterovirus in viral panels for febrile newborns.</p

    Coming out with the media: the ritualization of self-disclosure in the Dutch television program Uit de Kast

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    Using the media to disclose oneā€™s sexual identity has become an increasingly salient practice in recent years. Yet little is known about the reasons for the emergence of this form of self-disclosure. Based on an analysis of the Dutch television programme Uit de Kast (ā€˜Out of the Closetā€™), this article relates the rise of mediated coming out practices to the ritualizing power of the media: we argue that media plays a quintessential role in transforming the socially unscripted act of coming out into a patterned, culturally meaningful performance. Our analysis reveals that the ritual work of the programme is embedded in the ways 1) the generic format of the show structures the self-disclosures, 2) the authority of the media is deployed to channel the coming out process, and 3) the programme, while controlling diversity, reinforces dominant societal values and ideologies. The case not only highlights how unprecedented ritual forms come to flourish in the current era of ā€˜participatoryā€™ media culture, but also demonstrates how ritualization supports and naturalizes the claim that media is an effective agent to create order in everyday, ordinary lives

    Severe neonatal enterovirus infection in twins with different outcomes: A case report

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    Enteroviruses are among the most common causes of acute viral illness worldwide, and in neonates, the clinical course of these infections is heterogeneous. Severe complications, such as myocarditis, are associated with high mortality rates. In this case report, we present the clinical course of premature twins born at 35 weeks of gestational age, suffering from a severe neonatal enterovirus infection with cardiac involvement, which proved fatal in one of the twins. This course led to prompt identification in the other twin and facilitated timely transfer to a neonatal intensive care unit with neonatal hemodynamic expertise, and facilitated the timely transfer to a neonatal intensive care nit with hemodynamic expertise and immediate availability of AZCMO would it have been indicated. Early supportive therapy in the other twin contributed to a positive outcome. Therefore, we emphasize the importance of early recognition in averting adverse consequences. As a recommendation, we propose routine screening of enterovirus in viral panels for febrile newborns

    The Potential of MET Immunoreactivity for Prediction of Lymph Node Metastasis in Early Oral Tongue Squamous Cell Carcinoma

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    Objective MET positivity is independently associated with survival in oral squamous cell carcinoma (OSCC). Since MET is a known orchestrator of invasive tumor growth, we investigated its association with LNM in early oral tongue squamous cell carcinoma (OTSCC). As it is recommended by the NCCN to use tumor depth of invasion (DOI) in making decisions on elective neck dissection (END), the results obtained for MET positivity were aligned with those for DOI > 4 mm. The cutoff value used in our institution. Methods Tumor samples from patients who underwent primary tumor resection and neck dissection between 1995 and 2013, were collected from the archives of the Leiden and Erasmus University Medical Center. Immunohistochemistry with D1C2 was performed to identify MET negative (= 10% uniform positivity) cancers. ROC curve analysis and the Chi-squared test were used to investigate the association of MET positivity with LNM (pN+ and occult). Binary logistic regression was used to investigate the association of MET positivity with LNM. Results Forty-five (44.1%) of the 102 cancers were MET positive. Ninety were cN0 of which 20 were pN+ (occult metastasis). The remaining 12 cancers were cN+, of which 10 were proven pN+ and 2 were pN0. MET positivity was associated with LNM with a positive predictive value (PPV) of 44.4% and a negative predictive value (NPV) of 82.5% for pN+. For the occult group, the PPV was 36.8% and the NPV was 88.5%. Regression analysis showed that MET positivity is associated with pN+ and occult LNM (p-value < 0.05). Conclusion MET positivity is significantly associated with LNM in early OTSCC, outperforming DOI. The added value of MET positivity could be in the preoperative setting when END is being considered during the initial surgery. For cases with DO

    The State of Theory in LGBTQ Aging: Implications for Gerontological Scholarship

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    Social research in lesbian, gay, bisexual, transgender, and queer (LGBTQ) aging is a rapidly growing field, but an examination of the use of theory has not yet been conducted for its impact on the fieldā€™s direction. We conducted a systematic review of empirical articles published in LGBTQ aging in the years 2009ā€“2017 (N = 102). Using a typology of theory use in scholarly articles, we analyzed these articles for the types of theories being used, the degree to which theories were used in each article, and the analytical function they served. We found that 52% of articles consistently applied theory, 23% implied or partially applied theory, and 25% presented as atheoretical. A wide range of theories were used and served multiple analytical functions such as concept development and explanation of findings. We discuss the strengths and weaknesses of theory use in this body of literature, especially with respect to implications for future knowledge development in the field

    Morphological alterations of small intestinal epithelium of calves caused by feeding soybean protein.

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    The objective of this experiment was to detect alterations of small intestinal mucosa due to incorporation of large amounts of soybean protein in milk replacers and to relate these alterations to calf performance
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