Refractive index of a transparent liquid measured with a concave mirror

This paper describes the spherical concave mirror method for measuring the index of refraction of transparent liquids. We derived the refractive index equation using Snell's law and the small-angle approximation. We also verified the validity of this method using the traditional spherical mirror and thin-lens Gaussian equations.Comment: IOPart, 8 pages, 4 figure

Major variations in subtropical North Atlantic heat transport at short (5 day) timescales and their causes

Variability in the North Atlantic ocean heat transport at 26.5°N on short (5-day) timescales is identified and contrasted with different behaviour at monthly intervals using a combination of RAPID/MOCHA/WBTS measurements and the NEMO-LIM2 1/12° ocean circulation/sea ice model. Wind forcing plays the leading role in establishing the heat transport variability through the Ekman transport response of the ocean and the associated driving atmospheric conditions vary significantly with timescale. We find that at 5-day timescales the largest changes in the heat transport across 26.5°N coincide with north-westerly airflows originating over the American land mass that drive strong southward anomalies in the Ekman flow. During these events the northward heat transport reduces by 0.5-1.4 PW. In contrast, the Ekman transport response at longer monthly timescales is smaller in magnitude (up to 0.5 PW) and consistent with expected variations in the leading mode of North Atlantic atmospheric variability, the North Atlantic Oscillation. The north-westerly airflow mechanism can have a prolonged influence beyond the central 5-day timescale and on occasion can reduce the accumulated winter ocean heat transport into the North Atlantic by ∼40%

Full-depth temperature trends in the Northeastern Atlantic through the early 21st century

The vertical structure of temperature trends in the northeastern Atlantic (NEA) is investigated from a blend of Argo and hydrography data. The representativeness of sparse hydrography sampling in the basin-mean is assessed using a numerical model. Between 2003 and 2013, the NEA underwent a strong surface cooling (0-450?m) and a significant warming at intermediate and deep levels (1000?m-3000?m) that followed a strong cooling trend observed between 1988 and 2003. During 2003-2013, gyre-specific changes are found in the upper 1000?m (warming and cooling of the subtropical and subpolar gyres, respectively) whilst the intermediate and deep warming primarily occurred in the subpolar gyre, with important contributions from isopycnal heave and water mass property changes. The full-depth temperature change requires a local downward heat flux of 0.53?±?0.06?W?m?2 through the sea-surface, and its vertical distribution highlights the likely important role of the NEA in the recent global warming hiatus

A Rossby whistle: a resonant basin mode observed in the Caribbean Sea

We show that an important source of coastal sea level variability around the Caribbean Sea is a resonant basin mode. The mode consists of a baroclinic Rossby wave which propagates westward across the basin and is rapidly returned to the east along the southern boundary as coastal shelf waves. Almost two wavelengths of the Rossby wave fit across the basin, and it has a period of 120 days. The porous boundary of the Caribbean Sea results in this mode exciting a mass exchange with the wider ocean, leading to a dominant mode of bottom pressure variability which is almost uniform over the Grenada, Venezuela, and Colombia basins and has a sharp spectral peak at 120 day period. As the Rossby waves have been shown to be excited by instability of the Caribbean Current, this resonant mode is dynamically equivalent to the operation of a whistle

Blau\u27s Theory of Structural Differentiation Revisited: A Theory of Structural Change or Scale?

The major objective of this study was to determine if Blau\u27s (1970) theory of structural differentiation better captures differences in scale between organizations or structural changes within organizations. Data gathered on 134 Ph.D.-granting universities over nine years permitted us to compare results of within-organizations tests of Blau\u27s theory those from both cross-sectional and longitudinal between-organization tests. The findings suggest that the theory\u27s power lies in explaining structural differences between organizations rather than in explaining structural change

NEAT: An efficient network enrichment analysis test

Background: Network enrichment analysis is a powerful method, which allows to integrate gene enrichment analysis with the information on relationships between genes that is provided by gene networks. Existing tests for network enrichment analysis deal only with undirected networks, they can be computationally slow and are based on normality assumptions. Results: We propose NEAT, a test for network enrichment analysis. The test is based on the hypergeometric distribution, which naturally arises as the null distribution in this context. NEAT can be applied not only to undirected, but to directed and partially directed networks as well. Our simulations indicate that NEAT is considerably faster than alternative resampling-based methods, and that its capacity to detect enrichments is at least as good as the one of alternative tests. We discuss applications of NEAT to network analyses in yeast by testing for enrichment of the Environmental Stress Response target gene set with GO Slim and KEGG functional gene sets, and also by inspecting associations between functional sets themselves. Conclusions: NEAT is a flexible and efficient test for network enrichment analysis that aims to overcome some limitations of existing resampling-based tests. The method is implemented in the R package neat, which can be freely downloaded from CRAN ( https://cran.r-project.org/package=neat )

Somatostatin receptor in human hepatocellular carcinomas: Biological, patient and tumor characteristics

Background/Aim: The evidence on the efficacy of somatostatin analogues in the treatment of hepatocellular carcinoma (HCC) in humans is conflicting. A variety of human tumors demonstrate somatostatin receptors. All subtypes bind human somatostatin with high affinity, while somatostatin analogues bind with high affinity to somatostatin receptor subtype 2 (sst2). We investigated the sst2 expression in HCC and examined whether HCCs expressing sst2 are a distinct subgroup. Patients and Methods: Forty-five human HCCs were tested for sst2 expression and biological alterations. The proliferative capacity was determined with Ki67 immunostaining and the DNA ploidy status was measured by fluorescent in situ hybridization with a chromosome 1-specific repetitive DNA probe. Expression of tumor suppressor genes (p16, p53 and Rb1) was measured by immunohistochemistry. Results: sst2 expression was detected in 30 tumors (67%). No correlation existed between sst2 expression and the immunoprofiles of the tumor suppressor genes, aneuploidy, proliferation, age, gender, α-fetoprotein levels, tumor size, tumor grade and underlying liver disease. Conclusion: In 67% of the patients with HCC, sst2 could be detected in the tumor. No clinical, pathological or biological characteristics were specific for sst2-positive tumors. Copyrigh

Explosive trade-Offender types and interventions in economic firework crime

Het gebruik van professioneel vuurwerk is voor consumenten verboden. Desondanks wordt regelmatig gebruikgemaakt van professioneel vuurwerk door consumenten, bijvoorbeeld rondom de jaarwisseling of bij sportevenementen, waarbij het vuurwerk overlast veroorzaakt en een groot veiligheidsrisico vormt. Verder neemt het aantal aanslagen waarbij professioneel vuurwerk als explosief wordt ingezet de afgelopen jaren sterk toe. Voordat het vuurwerk bij deze eindgebruikers terechtkomt, heeft het een lange weg afgelegd vanuit het buitenland naar de illegale handel in zwaar vuurwerk binnen Nederland. De personen die betrokken zijn bij deze handel vormen de focus van dit onderzoek naar economische vuurwerkcriminaliteit. Onder professioneel vuurwerk valt momenteel al het vuurwerk met de categorie F4 en F3 van de Europese Pyrorichtlijn. Daarnaast valt F2-vuurwerk onder professioneel vuurwerk als dit niet in de Regeling aanwijzing consumenten- en theatervuurwerk (RACT) als consumentenvuurwerk wordt aangemerkt. Het onderzoek geeft verder inzicht in welke interventies voor het tegengaan van economische vuurwerkcriminaliteit effectief (kunnen) zijn, toegespitst op specifieke daderprofielen. In dit onderzoek wordt speciale aandacht besteed aan jeugdige daders in de leeftijd tot 23 jaar, mede vanuit de wens om scherper te krijgen wat de instroom en doorgroei van jongeren in deze criminele wereld kan voorkomen. Het onderzoek kent op grond van het voorgaande de volgende twee doelen: Het vergroten van het inzicht in de verschillende typen daders van economische vuurwerkcriminaliteit. Het vergroten van het inzicht in de bedoelde/onbedoelde effecten van straffen/interventies, zowel repressief als preventief en gespecificeerd naar typen daders. INHOUD Inleiding Huidige kennis Onderzoeksopzet Dadertypen economische vuurwerkcriminaliteit Jurisprudentieonderzoek Analyse van politie- en OBJD-data Experts over effecten van interventies Economische markt- en gedragsanalyse SyntheseRegular consumers are not permitted to use professional fireworks. Nevertheless, these types of fireworks are routinely set off by consumers in the Netherlands, for instance during New Year’s Eve and at sporting events, causing disturbance and posing a major safety risk. Also, the number of attacks using professional fireworks as explosives has increased strongly over the last few years. Before reaching the end users, these professional fireworks were imported from abroad to the illegal fireworks trade within the Netherlands. The people behind this illegal trade in professional fireworks are the focus of this current study on economic firework crime. In the Netherlands professional fireworks currently in clude all fireworks with the F4 and F3 category of the European Pyro Directive. In addition, F2-fireworks are considered professional if they are not classified as consumer fireworks in the Consumer and Theatre Fireworks Act (RACT). The current study provides insight into which interventions for combating economic fire work crime are (or can be) effective, focusing on specific offender profiles. In this research, special attention is paid to young offenders aged 22 and under, to (among other things) shed light onto what can prevent the influx and progression of young people in organized crime. Based on the above, the study has the following two objectives: Increasing understanding of the different types of perpetrators of economic fire work crime. Increasing understanding of the intended/unintended effects of punishments/in terventions, both repressive and preventive and specified by types of offenders

The fallacy of placing confidence in confidence intervals

Interval estimates – estimates of parameters that include an allowance for sampling uncertainty – have long been touted as a key component of statistical analyses. There are several kinds of interval estimates, but the most popular are confidence intervals (CIs): intervals that contain the true parameter value in some known proportion of repeated samples, on average. The width of confidence intervals is thought to index the precision of an estimate; CIs are thought to be a guide to which parameter values are plausible or reasonable; and the confidence coefficient of the interval (e.g., 95 %) is thought to index the plausibility that the true parameter is included in the interval. We show in a number of examples that CIs do not necessarily have any of these properties, and can lead to unjustified or arbitrary inferences. For this reason, we caution against relying upon confidence interval theory to justify interval estimates, and suggest that other theories of interval estimation should be used instead