How to tell the difference between a positive image and a stereotype: reading Priscilla, Queen of the Desert

This paper intervenes in critical discussions about the representation of homosexuality. Rejecting the ‘manifest content’ of films, it turns to cultural history to map those public discourses which close down the ways in which films can be discussed. With relation to The Adventures of Priscilla, Queen of the Desert, it examines discussions of the film in Australian newspapers (both queer and mainstream) and finds that while there is disagreement about the interpretation to be made of the film, the terms within which those interpretations can be made are quite rigid. A matrix based on similarity, difference and value provides a series of positions and a vocabulary (transgression, assimilation, positive images and stereotypes) through which to make sense of this film. The article suggests that this matrix, and the idea that similarity and difference provide a suitable axis for making sense of homosexual identity, are problematic in discussing homosexual representation.

旱生植物冷蒿（Artemisia frigida）的甲烷排放

本工作研究植物源CH4排放，即植物本身生成的CH4，不是厌氧微生物代谢产生的。目前对植物是否直接排放甲烷仍然存在很大争议：一方面实验中观测到的植物甲烷排放率差异较大；另一方面对植物甲烷排放内在机理仍不清楚。本文以旱生植物冷蒿(Artemisia frigida)为对象，测定冷蒿甲烷排放，分析冷蒿甲烷排放的可能存在的外界干扰因素。实验结果表明，冷蒿确实能够排放甲烷，冷蒿甲烷生成可能与活性氧代谢有关。 冷蒿是一种典型的旱生植物，其生长的典型草原中，土壤透气性好并表现为大气甲烷的汇。土壤孔隙间的甲烷浓度不高于大气甲烷浓度，能够通过植物根系进入植物体内的土壤甲烷量十分有限，植物组织又缺乏吸附甲烷的能力，很难在植物体内累积甲烷。因此，一些实验研究中所提出的植物蒸腾作用和细胞壁吸附作用对冷蒿的甲烷排放并没有显著影响。我们研究在实验室条件下冷蒿能否排放甲烷，无论是野外生长的冷蒿，还是室内无菌培养的冷蒿，都有明显的甲烷排放。通过研究植物呼吸作用与甲烷排放之间的相关性，我们发现两者有明显的线性关系。植物在应对环境胁迫时，呼吸电子传递链发生紊乱，导致活性氧的积累，这可能是植物所排放甲烷的主要来源。进而，我们通过活性氧添加实验证实包括超氧阴离子(•O2-)，羟基自由基(•OH)和过氧化氢(H2O2)在内的多种活性氧都能够促进冷蒿的甲烷排放，而抗氧化酶CAT则对冷蒿的甲烷排放具有抑制效果，我们认为这种抑制效果是通过对ROS的清除来实现的。冷蒿体内能够不断产生甲烷的途径可能需要活性氧的参与，植物体内自由基水平的高低，很可能决定了这种植物能否排放甲烷。因此，我们对比了四种植物体内的抗氧化酶活性。我们在抗氧化酶活性高的物种中没有测得甲烷的排放，而冷蒿和小叶锦鸡儿两种有明显甲烷排放的植物，其三种抗氧化酶活性均较低。由此我们认为，植物体内的活性氧与植物细胞内的某些成分发生反应并产生甲烷的过程很可能是植物体内清除活性氧，降低过氧化毒害的一种适应机制。

Evaluación de textos escolares.

Intentar conseguir nuevos procesos de investigación y de renovación del libro de texto para contribuir al perfeccionamiento cualitativo del texto. Necesidad de someter a revisión los esquemas evaluadores del libro de texto. El libro de texto. Evaluación del libro de texto: teorías, modelos, escalas sistemáticas de evaluación. Diseño descriptivo. Línea metodológica de caracter hermético. Entre las diversas variables que influyen en la calidad del producto educativo se estudia únicamente la variable de entrada de tipo formal e institucional, de carácter instrumental: el libro de texto. Diversos modelos de evaluación del libro de texto. Véase bibliografía. Análisis de contenido. Análisis de un elemento componente del Sistema Educativo: el libro de texto. Análisis comparativo entre distintos sistemas de valoración del libro de texto. Estudio crítico. Se establecen criterios para la elaboración de modelos de evaluación. Estos criterios son: formulación de objetivos, organización racionalizada de los contenidos científicos: pautas operativas, exigencia de actividad, pautas operativas, presentación de reforzamiento, atención a las diferencias individuales. Concepto de libro de texto ideal. Hay que acceder a la formalización de aquellos planteamientos operacionales que puedan orientar la estructuración de un modelo coherente de evaluación aplicable al conocimiento cualitativo de los libros de texto. La evaluación del libro de texto necesita abrirse a nuevas perspectivas que completen, modifiquen y amplien sus tradicionales trayectorias históricas.

Sufficients conditions for analysis of extrema in the step-response of the linear control systems

This note deals whith the problem of extrema which may occur in the step-response of a stable linear system with real zeros and poles. Some simple sufficients conditions and necessary conditions are presented for analyses when zeros located between the dominant and fastest pole does not cause extrema in the step-response. These conditions require knowledge of the pole-zero configuration of the corresponding transfer-function.

Morphometrical diagnosis of the malaria vectors Anopheles cruzii, An. homunculus and An. bellator

Background: Anopheles (Kerteszia) cruzii is a primary vector of Plasmodium parasites in Brazil's Atlantic Forest. Adult females of An. cruzii and An. homunculus, which is a secondary malaria vector, are morphologically similar and difficult to distinguish when using external morphological characteristics only. These two species may occur syntopically with An. bellator, which is also a potential vector of Plasmodium species and is morphologically similar to An. cruzii and An. homunculus. Identification of these species based on female specimens is often jeopardised by polymorphisms, overlapping morphological characteristics and damage caused to specimens during collection. Wing geometric morphometrics has been used to distinguish several insect species; however, this economical and powerful tool has not been applied to Kerteszia species. Our objective was to assess wing geometry to distinguish An. cruzii, An. homunculus and An. bellator. Methods: Specimens were collected in an area in the Serra do Mar hotspot biodiversity corridor of the Atlantic Forest biome (Cananeia municipality, State of Sao Paulo, Brazil). The right wings of females of An. cruzii (n= 40), An. homunculus (n= 50) and An. bellator (n= 27) were photographed. For each individual, 18 wing landmarks were subjected to standard geometric morphometrics. Discriminant analysis of Procrustean coordinates was performed to quantify wing shape variation. Results: Individuals clustered into three distinct groups according to species with a slight overlap between representatives of An. cruzii and An. homunculus. The Mahalanobis distance between An. cruzii and An. homunculus was consistently lower (3.50) than that between An. cruzii and An. bellator (4.58) or An. homunculus and An. bellator (4.32). Pairwise cross-validated reclassification showed that geometric morphometrics is an effective analytical method to distinguish between An. bellator, An. cruzii and An. homunculus with a reliability rate varying between 78-88%. Shape analysis revealed that the wings of An. homunculus are narrower than those of An. cruzii and that An. bellator is different from both of the congeneric species. Conclusion: It is possible to distinguish among the vectors An. cruzii, An. homunculus and An. bellator based on female wing characteristics.

The EU should tax in harmony. CEPS Commentary, 3 May 2012

Rather than expending unnecessary negative energy on the blunt and indiscriminate financial transaction tax (FTT), this commentary argues that the EU should give priority to its tax base harmonisation project. Progress on this front would advance several objectives at once: it would make an important step towards more economic union, it would promote the EU as a business location and it would succeed in appropriating tax income to the location where corporate activities are effectively exercised.