Allelopathic potential of macrofungi on germinating maize (Zea mays L.) grain

The effect of methanol extracts of 10 macrofungi was evaluated on grain germination of maize (Zea mays L.). Germination percentage, radicle and plumule length and the level of carbohydrates and fatty acids were measured. Fungal metabolites inhibited germination up to 90.96%, plumule (97.77%) and radicle (92.83%) development. Plumule and radicle lengths were stimulated 35.26 and 10.60% in some assays, respectively. The fungal metabolites decreased the glucose (97.60%), sucrose (90.34%), fructose (96.85%), maltose (95.64%), oleic acid (97.50%) and linoleic acid (98.25%) levels, whereas increasing levels of the glucose (165.14%), sucrose (166.53%), fructose (83.18%), maltose (124.73%), oleic acid (6975.00%) and linoleic acid (5233.33%) were detected in some assays. It is concluded that macrofungi metabolites have commonly inhibitory effects on physiological and morphological processes of germinating maize grain except for considerable increases in the some parameters investigated

Developing accident frequency prediction models for urban roads: A case study in São Paulo, Brazil

The growing number of vehicles and the evolving behaviour of road users present new and additional challenges to road safety. Study on the variables that influence the frequency of crash occurrences such as road geometry, junction, speed and land use are needed as they have proven effects on the number and severity of crashes. In this paper, we identify and assess the variables, namely road geometry, vehicle speed, traffic volume, land use and junction type, and develop accident frequency prediction models for a main urban transport corridor in São Paulo, Brazil. Crash data was provided by the traffic management company of the city, other datasets were obtained from a mix of primary and secondary sources including roadside cameras, Geographic Information Systems (GIS) and digital mapping tools. The studied road was segmented and the coefficients associated with variables in the segments were obtained using Poisson regression through a stepwise variable selection procedure. Two models with junctions density per type (access/km, T-junction unsignalised/km, T-junction signalised/km and crossroads/km) and junction density per merged type (signalised/km and unsignalised/km) along with land use per type (commercial and residential) are developed. The junction density and land use are found to be significant and positively correlated with crash frequency. The models were evaluated by statistical means for their accuracy of predicting the crashes, and validated with additional information obtained from field observation

3D thumbnails for 3D videos with depth

In this chapter, we present a new thumbnail format for 3D videos with depth, 3D thumbnail, which helps users to understand the content by preserving the recognizable features and qualities of 3D videos. The current thumbnail solutions do not give the general idea of the content and are not illustrative. In spite of the existence of 3D media content databases, there is no thumbnail representation for 3D contents. Thus, we propose a framework that generates 3D thumbnails from layered depth video (LDV) and video plus depth (V+D) by using two different methodologies on importance maps: Saliency-depth and layer based approaches. Finally, several experiments are presented that indicate 3D thumbnails are illustrative. © 2012, IGI Global

Particle dynamics in a class of 2-dimensional gravity theories

We provide a method to determine the motion of a classical massive particle in a background geometry of 2-dimensional gravity theories, for which the Birkhoff theorem holds. In particular, we get the particle trajectory in a continuous class of 2-dimensional dilaton gravity theories that includes the Callan-Giddings-Harvey-Strominger (CGHS) model, the Jackiw-Teitelboim (JT) model, and the $d$-dimensional $s$-wave Einstein gravity. The explicit trajectory expressions for these theories are given along with the discussions on the results.Comment: 15 pages, LaTeX. The deletion of the repeated portion of the abstract and the proper line wrapping of the tex file. No other change

Differences in weight status and energy-balance related behaviors among schoolchildren in German-speaking Switzerland compared to seven countries in Europe

BACKGROUND: Overweight in children and adolescents have increased significantly and are a major public health problem. To allow international comparisons, Switzerland joined the European study 'ENERGY' cross sectional survey consortium that investigated the prevalence of overweight and obesity as well as selected dietary, physical and sedentary behaviors of 10--12 years old pupils across seven other countries in Europe. The aims of the present study was to compare body composition and energy-balance related behaviors of Swiss schoolchildren to those of the seven European ENERGY-countries and to analyze overweight and energy-balance related behaviors of Swiss children according to socio-demographic factors. METHODS: A school-based cross-sectional study among 10--12 year old children was conducted in Switzerland and seven other European countries using a standardized protocol. Body height, weight and waist-circumference were measured by trained research assistants. Energy-balance related behaviors - i.e. selected dietary, physical activity and screen-viewing behaviors were assessed by questionnaires. Weight status and behaviors in Switzerland were compared to the seven European ENERGY countries. Within the Swiss sample, analyses stratified by gender, parental education and ethnicity were performed. RESULTS: Data of 546 Swiss children (mean age 11.6+/-0.8y, 48% girls) were obtained and compared to the EN

Magnetohydrodynamic equilibria of a cylindrical plasma with poloidal mass flow and arbitrary cross section shape

The equilibrium of a cylindrical plasma with purely poloidal mass flow and cross section of arbitrary shape is investigated within the framework of the ideal MHD theory. For the system under consideration it is shown that only incompressible flows are possible and, conscequently, the general two dimensional flow equilibrium equations reduce to a single second-order quasilinear partial differential equation for the poloidal magnetic flux function $\psi$, in which four profile functionals of $\psi$ appear. Apart from a singularity occuring when the modulus of Mach number associated with the Alfv\'en velocity for the poloidal magnetic field is unity, this equation is always elliptic and permits the construction of several classes of analytic solutions. Specific exact equlibria for a plasma confined within a perfectly conducting circular cylindrical boundary and having i) a flat current density and ii) a peaked current density are obtained and studied.Comment: Accepted to Plasma Physics & Controlled Fusion, 14 pages, revte

Conserved Quasilocal Quantities and General Covariant Theories in Two Dimensions

General matterless--theories in 1+1 dimensions include dilaton gravity, Yang--Mills theory as well as non--Einsteinian gravity with dynamical torsion and higher power gravity, and even models of spherically symmetric d = 4 General Relativity. Their recent identification as special cases of 'Poisson--sigma--models' with simple general solution in an arbitrary gauge, allows a comprehensive discussion of the relation between the known absolutely conserved quantities in all those cases and Noether charges, resp. notions of quasilocal 'energy--momentum'. In contrast to Noether like quantities, quasilocal energy definitions require some sort of 'asymptotics' to allow an interpretation as a (gauge--independent) observable. Dilaton gravitation, although a little different in detail, shares this property with the other cases. We also present a simple generalization of the absolute conservation law for the case of interactions with matter of any type.Comment: 21 pages, LaTeX-fil

Metabolic acceleration and the evolution of human brain size and life history.

Humans are distinguished from the other living apes in having larger brains and an unusual life history that combines high reproductive output with slow childhood growth and exceptional longevity. This suite of derived traits suggests major changes in energy expenditure and allocation in the human lineage, but direct measures of human and ape metabolism are needed to compare evolved energy strategies among hominoids. Here we used doubly labelled water measurements of total energy expenditure (TEE; kcal day(-1)) in humans, chimpanzees, bonobos, gorillas and orangutans to test the hypothesis that the human lineage has experienced an acceleration in metabolic rate, providing energy for larger brains and faster reproduction without sacrificing maintenance and longevity. In multivariate regressions including body size and physical activity, human TEE exceeded that of chimpanzees and bonobos, gorillas and orangutans by approximately 400, 635 and 820 kcal day(-1), respectively, readily accommodating the cost of humans' greater brain size and reproductive output. Much of the increase in TEE is attributable to humans' greater basal metabolic rate (kcal day(-1)), indicating increased organ metabolic activity. Humans also had the greatest body fat percentage. An increased metabolic rate, along with changes in energy allocation, was crucial in the evolution of human brain size and life history

Local search heuristics for the multidimensional assignment problem

The Multidimensional Assignment Problem (MAP) (abbreviated s-AP in the case of s dimensions) is an extension of the well-known assignment problem. The most studied case of MAP is 3-AP, though the problems with larger values of s also have a large number of applications. We consider several known neighborhoods, generalize them and propose some new ones. The heuristics are evaluated both theoretically and experimentally and dominating algorithms are selected. We also demonstrate that a combination of two neighborhoods may yield a heuristics which is superior to both of its components

Adolescents and parental caregivers as lay health advisers in a community-based risk reduction intervention for youth: baseline data from Teach One, Reach One

The purpose of the current study is to describe the demographic, behavioral, and psychosocial characteristics of adolescent and caregiver lay health advisers (LHAs) participating in an intervention designed to reduce risk behaviors among rural African-American adolescents. Teach One, Reach One integrates constructs from the Theory of Planned Behavior and Social Cognitive Theory. It acknowledges that changing the sexual behaviors of African-American adolescents requires changing one's knowledge, attitudes, normative beliefs about the behavior of peers, and self-efficacy regarding adolescent sexual behavior, parent–teen communication about sex, and healthy dating relations among adolescents. Study participants completed baseline questionnaires assessing demographics and psychosocial determinants (knowledge, attitudes, perceived social norms, and self-efficacy) of sexual behaviors. Sixty-two adolescent and caregiver dyads participated. Caregivers included biological parents, legal guardians, or other parental figures. Strengths and areas in need of improvement were determined using median splits. Few adolescents had initiated sex. Their strengths included high levels of open parent–teen communication; positive attitudes and normative beliefs regarding both sex communication and healthy dating relationships; and high knowledge and self-efficacy for healthy dating behaviors. Areas needing improvement included low knowledge, unfavorable attitudes, poor normative beliefs, and low self-efficacy regarding condom use. Caregiver strengths included positive attitudes, normative beliefs, and self-efficacy for sex communication; positive attitudes and self-efficacy for condom use; and low acceptance of couple violence. Areas needing improvement included low levels of actual communication about sex and low knowledge about effective communication strategies and condom use. The current study highlights the value of assessing baseline characteristics of LHAs prior to intervention implementation, as it enables a better understanding of the key characteristics necessary for planning and implementing interventions, as well as engaging in targeted training activities