Search results for "Production"
showing 10 items of 7600 documents
Crossed induction of sex in sympatric congeneric rotifer populations
2009
The transition from asexual to sexual reproduction in rotifers of the genus Brachionus (Monogononta) is triggered by a chemical signal produced and released by the rotifers themselves; the signal accumulates in the environment as population density increases. The response to this signal has been hypothesized to be speciesspecific. If not, the timing of sex and final diapausing egg production of a species might not be optimized. In this study, a set of experiments—based on individual and mass culture approaches—was carried out to investigate the differentiation in sex induction signals between sympatric and allopatric congeneric Brachionus populations by analyzing the capability of the mediu…
From sentence production to text production: Investigating fundamental processes
1991
The purpose of the present article is to present a nom exhaustive review about the cognitive psychology research in english and in french language, dealing with the study of the organization and the functioning of the oral and written language production mechanisms.
Search for promptly produced heavy quarkonium states in hadronic Z decays
1996
A search has been made for direct production of heavy quarkonium states in more than 3 million hadronic Z^{0} decays in the 1991-1994 DELPHI data. Prompt J/\psi, \psi(2S) and \Upsilon candidates have been searched for through their leptonic decay modes using criteria based on the kinematics and decay vertex positions. New upper limits are set at the 90 \% confidence level for {Br( Z^0 \rightarrow \left( Q \bar{Q} \right) X ) / Br( Z^0 \rightarrow \mbox{hadrons})} for various strong production mechanisms of J/\psi and \Upsilon; these range down to 0.9 \times 10^{-4}. The limits are set in the presence of a small excess (\sim 1 \% statistical probability of a background fluctuation) in the su…
Evolution of the grapevine (Vitis viniferaL.) imprinted by natural and human factorsThis review is one of a selection of papers presented at the symp…
2007
This paper is concerned with vegetative reproduction, which is the only mode of propagation in cultivated grapevines. After a brief summary of the systematics of the Vitaceae the question of the nomenclature of cultivated grapevines is discussed. Intra-varietal variability is discussed using morphological and molecular characteristics. The origins of variation are presented: mutations, foreign nucleic acids, and memory of previous environmental conditions. Grapevines provide characteristic products, leading viticulturalists to make selections among the diversity observed in the vineyard, thus decreasing diversity. Grapevines interact with various environmental agents. One example, the natur…
Soil Erosion Induced by the Introduction of New Pasture Species in a Faxinal Farm of Southern Brazil
2018
The faxinal management system is an endangered agro-silvopastoral system which forms part of the local traditional management in the Paraná federal state (Brazil). Significant changes in land management since the 1970s caused farmers to look for alternatives to increase the productivity of their farms. The introduction of new pasture species is causing land degradation problems, of which soil erosion is the most important challenge. Therefore, in this study, we assessed the environmental consequences of introducing exotic pasture species, such as Brachiaria decumbens. To achieve this goal, ten erosion plots were installed with exotic and native pastures (Paspalum notatum Flügg&e…
New results on the Roper resonance and the P_{11} partial wave
2008
Properties of the Roper resonance, the first scalar excitation of the nucleon, are determined. Pole positions and residues of the $P_{11}$ partial wave are studied in a combined analysis of pion- and photo-induced reactions. We find the Roper pole at $\{(1371\pm7)-i(92\pm10)\}$ MeV and an elasticity of $0.61\pm 0.03$. The largest decay coupling is found for the $N\sigma$ ($\sigma=(\pi\pi)$-$S$-wave). The analysis is based on new data on $\gamma p\to p\pi^0\pi^0$ for photons in the energy range from the two-pion threshold to 820 MeV from TAPS at Mainz and from 0.4 to 1.3 GeV from Crystal Barrel at Bonn and includes further data from other experiments. The partial wave analysis excludes the p…
Dall'impresa gerarchica alla comunità distribuita
2014
This article describes the emergence of collaborative production systems, that is those decentralized systems, different from markets and firms, where a community a loosely connected people, with a range of diverse and primarily intrinsic motivation, engage in a large scale collaboration whose outputs are governed as commons (e.g. open software, open hardware, etc.). After a description of the relationship between market system and managerial hierarchy, and the costs connected to each of these systems, the article exposes how peer production is usually organized and identifies the relative advantages of this organizational model over markets and firms under given circumstances. In the last …
Research and development expenditure in France : an analysis by sector
1996
La taille des entreprises a toujours été considérée comme une variable déterminante dans l'explication de leurs stratégies (stratégie de concentration ou stratégie d'innovation). Ce travail se propose d'analyser la relation évoquée par J. Schumpeter entre la taille des entreprises et le montant des dépenses en recherche-développement. Tout en suivant la méthodologie utilisée en Economie Industrielle, nous avons d'abord conduit une analyse exploratoire sur cette relation. Cette étude, réalisée au niveau branche, montre que la taille (mesurée par le nombre de salariés, la production effective ou la valeur ajoutée) exerce une influence positive sur les dépenses en recherche-développement (mesu…
Dinosaur bonebed amber from an original swamp forest soil
2021
AbstractDinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer namely composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeont…
Anaerobic Degradation of Environmentally Hazardous Aquatic Plant Pistia stratiotes and Soluble Cu(II) Detoxification by Methanogenic Granular Microbi…
2021
The aquatic plant Pistia stratiotes L. is environmentally hazardous and requires effective methods for its utilization. The harmfulness of these plants is determined by their excessive growth in water bodies and degradation of local aquatic ecosystems. Mechanical removal of these plants is widespread but requires fairly resource-intensive technology. However, these aquatic plants are polymer-containing substrates and have a great potential for conversion into bioenergy. The aim of the work was to determine the main patterns of Pistia stratiotes L. degradation via granular microbial preparation (GMP) to obtain biomethane gas while simultaneously detoxifying toxic copper compounds. The compos…