96 research outputs found
Residu de Grothendieck et forme de Chow
We show an explicit relation between the Chow form and the Grothendieck residue; and we clarify the role that the residue can play in the intersection theory besides its role in the division problem
Recognizing greenway network for quantifying students experience on campus-based universities : assessing the campus outdoor spaces at San Diego State University
This paper evaluates the potential of creating a green infrastructure – more specifically, an urban greenway – and its contribution the students’ campus experience, with emphasis on the outdoor university activities. To achieve best value for money – particularly in the current financial climate, with severe budget cuts constraining universities – justifying investments on campus outdoor spaces such as greenways, relies on a clear demonstration of their link to the overall success of the campus. Attempts of quantify the benefits from investments on such spaces are challenged by the scarcity of studies on the relationship between students’ experience and design (and related cost) of different types of campus landscape settings. This paper fills this gap by offering a thorough examination of a variety of extant campus developments and by measuring the performance of some selected open spaces against a ‘price-tag’ mechanism. The case study of the San Diego State University has been chosen as core case study and supplemented by 16 sub-cases across California State. The assessment has been conducted through three steps. First, a site inventory of the physical characteristics and landscape features has been conducted, focusing on 7 typologies of campus outdoor spaces (COS). Second, four main use patterns (Individual-customized, Group-social, Programmed-scheduled, and Active experiences) have been assessed by calculating the intensity of use (function of the frequency and duration of use) for each of them. The data collected was based on syntax observation methods with photos and maps of COS as prompts. Third, a Campus-Experience-Score (C-E-C) has been calculated and normalized to the size and population of the university, matching it against the actual development costs of each COS setting. The C-E-C allows measuring the link between types and features of COS and related students’ experience. Findings were discussed and verified through six in-depth interviews with local and international academics and developers/practitioners. This paper offers valuable benchmark to designers and planners seeking to maximize the value for money of investments on COS such as greenways
Resultant-based methods for plane curves intersection problems
http://www.springeronline.com/3-540-28966-6We present an algorithm for solving polynomial equations, which uses generalized eigenvalues and eigenvectors of resultant matrices. We give special attention to the case of two bivariate polynomials and the Sylvester or Bezout resultant constructions. We propose a new method to treat multiple roots, detail its numerical aspects and describe experiments on tangential problems, which show the efficiency of the approach. An industrial application of the method is presented at the end of the paper. It consists in recovering cylinders from a large cloud of points and requires intensive resolution of polynomial equations
A New Solution to the Relative Orientation Problem using only 3 Points and the Vertical Direction
This paper presents a new method to recover the relative pose between two
images, using three points and the vertical direction information. The vertical
direction can be determined in two ways: 1- using direct physical measurement
like IMU (inertial measurement unit), 2- using vertical vanishing point. This
knowledge of the vertical direction solves 2 unknowns among the 3 parameters of
the relative rotation, so that only 3 homologous points are requested to
position a couple of images. Rewriting the coplanarity equations leads to a
simpler solution. The remaining unknowns resolution is performed by an
algebraic method using Grobner bases. The elements necessary to build a
specific algebraic solver are given in this paper, allowing for a real-time
implementation. The results on real and synthetic data show the efficiency of
this method
Solving special polynomial systems by using structured matrices and algebraic residues
Turkish D-light : accentuating heritage values with daylight
Historic buildings have their own cultural identity, which is often related to their aesthetic qualities such as period
characteristics (geometry, size, colour, form and shape), materials and construction. Daylight is one of the primary
elements contributing to the distinctiveness of the visual environment of many historic buildings, but is rarely
considered as one of the components that shape the character of a building when adaptive preservation schemes of
historical buildings are planned. Many historic buildings were originally designed to accommodate activities different to
their new use and preserving the quality of daylight that originally contributed to their visual identity is a challenging
task. Maintaining the ‘day-lit appearance’ of a building can be particularly problematic if the building is to be used as a
museum or a gallery owing to the artefacts’ conservation requirements. This work investigated the opportunities of
maintaining the original ambient conditions of renovated historical buildings while meeting the required daylight levels
of the proposed new use. The study utilised an annual daylight simulation method and hourly weather data to preserve
daylight conditions in renovated historic buildings. The model was piloted in a Turkish bathhouse situated in Bursa,
Turkey, that is currently under renovation. The simulation model produces 4483 hourly values of daylight illuminance
for a period of a whole year using the computer program Radiance. It is concluded that daylight characteristics should
be taken into account when developing a renovation scheme. With increasing pressure on valuing historic buildings in
many parts of the world, the work reported here should be beneficial to those concerned with the conservation and
adaptive reuse of historic buildings. The study findings could also be useful to those interested in predicting potential
energy savings by combining daylighting and electric lighting in historic buildings
Does having a twin-brother make for a bigger brain?
Objective: Brain volume of boys is larger than that of girls by ∼10%. Prenatal exposure to testosterone has been suggested in the masculinization of the brain. For example, in litter-bearing mammals intrauterine position increases prenatal testosterone exposure through adjacent male fetuses, resulting in masculinization of brain morphology. Design: The influence of intrauterine presence of a male co-twin on masculinization of human brain volume was studied in 9-year old twins. Methods: Magnetic resonance imaging brain scans, current testosterone, and estradiol levels were acquired from four groups of dizygotic (DZ) twins: boys from same-sex twin-pairs (SSM), boys from opposite-sex twin-pairs (OSM), girls from opposite-sex twin-pairs (OSF), and girls from same-sex twin-pairs (SSF; n=119 individuals). Data on total brain, cerebellum, gray and white matter volumes were examined. Results: Irrespective of their own sex, children with a male co-twin as compared to children with a female co-twin had larger total brain (+2.5%) and cerebellum (+5.5%) volumes. SSM, purportedly exposed to the highest prenatal testosterone levels, were found to have the largest volumes, followed by OSM, OSF and SSF children. Birth weight partly explained the effect on brain volumes. Current testosterone and estradiol levels did not account for the volumetric brain differences. However, the effects observed in children did not replicate in adult twins. Conclusions: Our study indicates that sharing the uterus with a DZ twin brother increases total brain volume in 9-year olds. The effect may be transient and limited to a critical period in childhood. © 2009 European Society of Endocrinology
A Novel Therapy for Melanoma Developed in Mice: Transformation of Melanoma into Dendritic Cells with Listeria monocytogenes
Listeria monocytogenes is a gram-positive bacteria and human pathogen widely used in cancer immunotherapy because of its capacity to induce a specific cytotoxic T cell response in tumours. This bacterial pathogen strongly induces innate and specific immunity with the potential to overcome tumour induced tolerance and weak immunogenicity. Here, we propose a Listeria based vaccination for melanoma based in its tropism for these tumour cells and its ability to transform in vitro and in vivo melanoma cells into matured and activated dendritic cells with competent microbicidal and antigen processing abilities. This Listeria based vaccination using low doses of the pathogen caused melanoma regression by apoptosis as well as bacterial clearance. Vaccination efficacy is LLO dependent and implies the reduction of LLO-specific CD4+ T cell responses, strong stimulation of innate pro-inflammatory immune cells and a prevalence of LLO-specific CD8+ T cells involved in tumour regression and Listeria elimination. These results support the use of low doses of pathogenic Listeria as safe melanoma therapeutic vaccines that do not require antibiotics for bacterial removal
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