Search results for " form"

Dimensions of invasiveness: Links between local abundance, geographic range size, and habitat breadth in Europe's alien and native floras.

2021

Understanding drivers of success for alien species can inform on potential future invasions. Recent conceptual advances highlight that species may achieve invasiveness via performance along at least three distinct dimensions: 1) local abundance, 2) geographic range size, and 3) habitat breadth in naturalized distributions. Associations among these dimensions and the factors that determine success in each have yet to be assessed at large geographic scales. Here, we combine data from over one million vegetation plots covering the extent of Europe and its habitat diversity with databases on species' distributions, traits, and historical origins to provide a comprehensive assessment of invasive…

Basal ice formation in snow cover in Northern Finland between 1948 and 2016

2018

Major trends in stem anatomy and growth forms in the perianth-bearing Piperales, with special focus on Aristolochia.

2014

International audience; BACKGROUND AND AIMS: The order Piperales has the highest diversity of growth forms among the earliest angiosperm lineages, including trees, shrubs, climbers and herbs. However, within the perianth-bearing Piperales (Asarum, Saruma, Lactoris, Hydnora, Prosopanche, Thottea and Aristolochia), climbing species only occur in the most species-rich genus Aristolochia. This study traces anatomical and morphological traits among these lineages, to detect trends in growth form evolution and developmental processes. METHODS: Transverse stem sections of different developmental stages of representatives of Asarum, Saruma, Lactoris, Hydnora, Thottea and Aristolochia were compared …

Social immunity and the evolution of group living in insects

2015

The evolution of group living requires that individuals limit the inherent risks of parasite infection. To this end, group living insects have developed a unique capability of mounting collective anti-parasite defences, such as allogrooming and corpse removal from the nest. Over the last 20 years, this phenomenon (called social immunity) was mostly studied in eusocial insects, with results emphasizing its importance in derived social systems. However, the role of social immunity in the early evolution of group living remains unclear. Here, I investigate this topic by first presenting the definitions of social immunity and discussing their applications across social systems. I then provide a…

Mechanical properties of natural fiber composites produced using dynamic sheet former

2018

Composites formed from wood fibers and man-made cellulosic fibers in PLA (polylactic acid) matrix, manufactured using sheet forming technique and hot pressing, are studied. The composites have very low density (due to high porosity) and rather good elastic modulus and tensile strength. As expected, these properties for the four types of wood fiber composites studied here improve with increasing weight fraction of fibers, even if porosity is also increasing. On the contrary, for man-made cellulosic fiber composites with circular fiber cross-section, the increasing fiber weight fraction (accompanied by increasing void content) has detrimental effect on stiffness and strength. The differences …

Methodology for determining foliar penetration of herbicides with reference to oil-based adjuvants

1994

Oils are used extensively in pesticide formulation and in pesticide application as spray adjuvants. They improve the biological efficacy of several foliage-applied herbicides without impairing their selectivity. Beneficial effects were first observed with atrazine in maize (Zea mays; Jones and Anderson 1968; Nalewaja 1968) and with phenmedipham in sugar beet (Beta vulgaris: Miller and Nalewaja 1973). More recently, oils have met with success as spray adjuvants for graminicides (Buhler and Burnside 1984; Nalewaja 1986; Barrentine and McWorther 1988) and for bentazone (Doran and Andersen 1975; Nalewaja et al. 1975). Since they allow the use of reduced herbicide application rates, oils also im…

European Formalism and Empiriocriticism : Formalism within the International Empiriocritical Movement

2020

Abstract This paper argues that Russian Formalism is to be considered a constitutive part of the international empiriocritical movement—Ernst Mach (1838—1916) and Richard Avenarius’s (1843—1896). The conceptual parallelism between Empiriocriticism and Formalism is striking indeed. Thus, the cornerstones of the empiriocritical approach—the concept of series [Reihe] and the concept of elements [Elemente], understood as sensations [Empfindungen]—are plainly recognizable within formalist theories: the notion of ‘series’ (for example, the notion of ‘literary series’ or ‘poetic series’, leading to the famous concept of ‘literariness’, literaturnost’) and the very formalist idea of a necessarily p…

Sphingomonas solaris sp. nov., isolated from a solar panel in Boston, Massachusetts

2020

Solar panel surfaces, although subjected to a range of extreme environmental conditions, are inhabited by a diverse microbial community adapted to solar radiation, desiccation and temperature fluctuations. This is the first time a new bacterial species has been isolated from this environment. Strain R4DWNT belongs to the genus Sphingomonas and was isolated from a solar panel surface in Boston, MA, USA. Strain R4DWNT is a Gram-negative, non-motile and rod-shaped bacteria that tested positive for oxidase and catalase and forms round-shaped, shiny and orange-coloured colonies. It is mesophilic, neutrophilic and non-halophilic, and presents a more stenotrophic metabolism than its closest neighb…

Humusica 1, article 1: Essential bases – Vocabulary

2018

International audience; The Special Issue Humusica 1 corresponds to a field guide for the classification of terrestrial humus systems and forms. The present first article of the issue defines vocabulary, objects and concepts necessary for: (a) field investigation, (b) understanding the process of classification, (c) assigning ecological significance to the defined morpho-functional units, (d) discussing and exchanging scientific data about humus systems. The article starts with general considerations, as the necessity humans have to classify natural objects for sharing ideas and information on them. Then the article focuses on soil as functional element of every ecosystem. Historical and re…

The effect of low frequency noise on the behaviour of juvenile Sparus aurata.

2020

[EN] Anthropogenic activities are causing increased noise levels in the marine environment. To date, few studies have been undertaken to investigate the effects of different noise frequencies on the behaviour of juvenile fish. In this study, the behavioural changes of juvenile gilthead seabream (Sparus aurata) are evaluated when exposed to white noise filtered in third-octave bands centred at 63, 125, 500, and 1000 Hz (sound pressure level, 140-150 dB re 1 mu& x3a1;a) for 7 h. The group dispersion, motility, and swimming height of the fish were analysed before and during the acoustic emission. Dispersion of the fish was found to reduce immediately upon application of low frequency sound (63…