Genetic control of male fertility in Arabidopsis thaliana : structural analysis of premeiotic developmental mutants

We have taken a mutational approach to identify genes important for male fertility in Arabidopsis thaliana and have isolated a number of nuclear male/ sterile mutants in which vegetative growth and female fertility are not altered. Here we describe detailed developmental analyses of four mutants, each of which defines a complementation group and has a distinct developmental end point. All four mutants represent premeiotic developmental lesions. In ms3, tapetum and middle layer hypertrophy result in the degeneration of microsporocytes. In ms4, microspore dyads persist for most of anther development as a result of impaired meiotic division. In ms5, degeneration occurs in all anther cells at an early stage of development. In ms15, both the tapetum and microsporocytes degenerate early in anther development. Each of these mutants had shorter filaments and a greater number of inflorescences than congenic male-fertile plants. The differences in the developmental phenotypes of these mutants, together with the non-allelic nature of the mutations indicate that four different genes important for pollen development, have been identified.

Raat Ki Rani : nightclubs, vamps and urban transgressive spaces in Hindi cinema

This paper considers how city spaces in Hindi cinema have repeatedly been viewed as sites of transgressive sexual experience, particularly via representations of female sexuality in nightclubs and the flagrant performances of the women or ‘vamps’ that inhabit them. Emerging in Hindi cinema in the 1950s, and becoming a staple in films of the 1960s and 1970s, the ‘vamp’ became synonymous with unrestrained sexuality and the immorality of the city. The dichotomy between the idealised, bucolic, timeless village and the city as an icon of degenerate modernity was repeatedly seen in Hindi cinema, and the strongest signifier of this urban immorality was the ‘vamp’ who was seen as an outsider, and connoted urban vice, excess and desire. By and large the actresses that played ‘vamps’ (such as the blonde haired and blue eyed Helen) were of ‘Western’ appearance. The cabaret and nightclub were thus seen as being ‘Western’ in origin. This paper discusses how this was perhaps a response to colonial and Orientalist stereotyping, where the ‘Indian’ woman and the ‘Western’ woman operated as binary oppositional structures. Such oppositions were clearly present in nightclub dance performances, which were full of meaning to the cinematic audience, who would be able to ‘read’ the seductive, gyrating and explicit movements. This paper decodes examples of the movements in these ‘decadent’ performances, as it was through these movements and performances that the ‘westernised vamp’ became firmly located in urban transgressive spaces, closely tied with national anxiety about the depravity of city spaces.

Tree façades : generative modelling with an axial branch rewriting system

The methods and algorithms of generative modelling can be improved when representing organic structures by the study of computational models of natural processes and their application to architectural design. In this paper, we present a study of the generation of branching structures and their application to the development of façade support systems. We investigate two types of branching structures, a recursive bifurcation model and an axial tree based L-system for the generation of façades. The aim of the paper is to capture not only the form but also the underlying principles of biomimicry found in branching. This is then tested, by their application to develop experimental façade support systems. The developed algorithms implement parametric variations for façade generation based on natural tree-like branching. The benefits of such a model are: ease of structural optimization, variations of support and digital fabrication of façade components.

Blind extraction using fractional lower-order statistics

In traditional method to blindly extract interesting source signals sequentially, the second-order or higher-order statistics of signals are often utilized. However, for impulsive sources, both of the second-order and higher-order statistics may degenerate. Therefore, it is necessary to exploit new method for the blind extraction of impulsive sources. Based on the best compression-reconstruction principle, a novel model is proposed in this work, together with the corresponding algorithm. The proposed method can be used for blind extraction of sources which are distributed from alpha stable process. Simulations are given to illustrate availability and robustness of our algorithm.

Nonorthogonal approximate joint diagonalization with well-conditioned diagonalizers

To make the results reasonable, existing joint diagonalization algorithms have imposed a variety of constraints on diagonalizers. Actually, those constraints can be imposed uniformly by minimizing the condition number of diagonalizers. Motivated by this, the approximate joint diagonalization problem is reviewed as a multiobjective optimization problem for the first time. Based on this, a new algorithm for nonorthogonal joint diagonalization is developed. The new algorithm yields diagonalizers which not only minimize the diagonalization error but also have as small condition numbers as possible. Meanwhile, degenerate solutions are avoided strictly. Besides, the new algorithm imposes few restrictions on the target set of matrices to be diagonalized, which makes it widely applicable. Primary results on convergence are presented and we also show that, for exactly jointly diagonalizable sets, no local minima exist and the solutions are unique under mild conditions. Extensive numerical simulations illustrate the performance of the algorithm and provide comparison with other leading diagonalization methods. The practical use of our algorithm is shown for blind source separation (BSS) problems, especially when ill-conditioned mixing matrices are involved.

Surface wrinkling of the twinning induced plasticity steel during the tensile and torsion tests

'Heterogeneous twinning' is defined as plastic deformation due to the formation and progress of twins resulting in surface wrinkles on the deforming part when the initial grain size is relatively large compared to the typical size of the part. In the case of a Twinning Induced Plasticity (TWIP) steel with an initial grain size of ~160. m, the heterogeneous twinning generated visible wrinkles, an orange peel effect, under medium uni-axial strains. The heterogeneous twinning did not occur in the material subjected to high shear strains. The complications resulting from this phenomenon on strain hardening characterization of the TWIP steels using two commonly used mechanical tests, tensile and torsion are discussed along with some experimental aspects of heterogeneous twinning. © 2014.

Dynamic cloud service selection using an adaptive learning mechanism in multi-cloud computing

Cloud service selection in a multi-cloud computing environment is receiving more and more attentions. There is an abundance of emerging cloud service resources that makes it hard for users to select the better services for their applications in a changing multi-cloud environment, especially for online real time applications. To assist users to efficiently select their preferred cloud services, a cloud service selection model adopting the cloud service brokers is given, and based on this model, a dynamic cloud service selection strategy named DCS is put forward. In the process of selecting services, each cloud service broker manages some clustered cloud services, and performs the DCS strategy whose core is an adaptive learning mechanism that comprises the incentive, forgetting and degenerate functions. The mechanism is devised to dynamically optimize the cloud service selection and to return the best service result to the user. Correspondingly, a set of dynamic cloud service selection algorithms are presented in this paper to implement our mechanism. The results of the simulation experiments show that our strategy has better overall performance and efficiency in acquiring high quality service solutions at a lower computing cost than existing relevant approaches.

Mixed feelings: Anglo-Indians and the distribution of the sensible in Indian cinema

Hollywood, and various regional cinemas in India typically represent Mixed-Race Anglo-Indians as a degenerate community marked by lax morals, alcoholism, and indolence. These stereotypical tropes typically generate indignant protests from members of this miniscule Indian community, and debates about the representation of Anglo-Indians focus on the injustices propagated by such stereotypes. This paper rethinks Anglo-Indian representation in cinema by drawing on Jacques Rancière’s concept of ‘the distribution of the sensible,’ which provides a cartography for understanding how one’s various identity assignations structure sensory experience. In other words those who are marginalized have ways of seeing and hearing from those occupy normative or dominant subject positions, and these differences are best approached in terms of neo-Kantian aesthetic judgment. It also argues, with Rancière, that ‘inequality’ is built into the distribution of the sensible. Drawing on a number of Indian and Hollywood films — including Aparna Sen’s 36 Chowringhee Lane (1981) Anjan Dutt’s Bada Din (1998) Ismail Merchant’s Cotton Mary (2000), Bow Barracks Forever (2004) and Harry McClure’s Going Away (2013) — the paper contends that Rancière’s ‘distribution of the sensible’ allows us to think through a politics that is connected to ‘aesthetic judgement’ as well as a politics of differentiation that informs our understanding of the function of minoritarian characters in narrative cinema.