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Copyright of Ecologia Mediterranea is the property of Ecologia Mediterranea and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: In this Note, we study numerically turbulent diffusion in the case of homogeneous stably stratified turbulence. This study is based on a linear analysis in spectral space. To express the Lagrangian velocity correlations using Eulerian correlations, we adapt the Corrsin assumption and then we calculate the tensor components of the mean square displacement. We begin by writing the basic linear equations governing the evolution of the spectra of double correlations then we present the Corrsin hypothesis as a model of turbulent diffusion. Subsequently, we describe the numerical method used and analyze the numerical results. Clearly, the Corrsin assumption can give the proper behavior, at large times, of the horizontal diffusion and improves the prediction of vertical diffusion. As an application of the numerical code elaborated, we study the influence of Prandtl number on the vertical diffusion which results in an accentuation of the suppression of vertical diffusion when the Prandtl number (less than 1) diminishes. [Copyright &y& Elsevier]

Abstract: SubPcBCl is synthesized from 1,4-benzene diboronic acid with a yield of 45%. The infrared, electronic and proton NMR spectra are in accordance with the results of literature. [Copyright &y& Elsevier]

We present a simulation of the vocal source, known as the two-mass model. It simulates the human vocal folds. We are starting a qualitative study of the effects of the source-conduit coupling on the shape and spectrum of the glottal wave. This simulation should give us a better understanding the acoustic production of speech. [ABSTRACT FROM AUTHOR]

(NH4)5H2PMo11MII O40 (M: Co, Ni), (NH4)4H2PMo11FeIII (H2O)O39 (PMo11M) and (NH4)2,5MxHyPMo12O40 (MPMo12) mixed salts with M = Ni, Co, Fe were synthesised and analyzed by IR and UV-Vis spectroscopies, X-Ray diffraction, thermal analysis (TG), differential scanning calorimetry (DSC) and BET analysis. Their catalytic, acid-base and redox properties were examined in the probe reaction of 2-propanol conversion at 150°C. The obtained results have shown that both nature of the coordination cation and its position in the polyoxometallate (inside Keggin unit, PMo11M or outside Keggin unit, MPMo12) play an important role on these properties. [ABSTRACT FROM AUTHOR]

Characterization of instabilities modes downstream an open cavity of various shape. In this paper, we have studied and characterized experimentally by the technique of measure Laser Doppler Velocimetry (LDV) the vortex shedding frequency. The study is conducted by changing the cavity length and height and the external flow velocity and therefore the flow patterns inside the cavity. The variation of the Strouhal number according to the Reynolds number, led us to a regrouping for every mode, permitting to really separate the mode the some of the other. [ABSTRACT FROM AUTHOR]

Copyright of Lettre de Medecine Physique et de Readaptation is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The chemical preparation, thermal analysis, crystal structure and IR spectroscopic investigation of (C10H26N4)(H2PO4)2.4H2O are described. The compound crystallizes in the monoclinic system with C2/c space group. Its unit cell dimensions are: a = 14.414(3) Å; b = 8.037(2) Å; c = 19.275(2) Å; β = 95.33(1)°; V = 2223.3(8) ų and Z = 4. The structure is built up from inorganic chains parallel to the b axis, linked via 0-H0 bonds. These chains are interconnected by water molecules. Thermal analysis reveals the presence of four water molecules in the structure. The IR spectrum of this new compound is reported and discussed on the basis of group theoretical analysis. [ABSTRACT FROM AUTHOR]

Abstract: The imaging of gliomas, as well as diffuse infiltrative gliomas or as more recently individualized entities, has been profoundly modified these last years. Correlated with the classic morphological MRI, numerous new sequences have appeared that allowed a more metabolic approach of the tumors, such as diffusion, perfusion – related to angiogenesis – and spectroscopy – reflecting metabolic data. Their development in daily practice allows to precise the diagnostic, to definite the more active areas (correlated with the hyperperfused or more metabolic active areas in relation with the Ki67 index) and so optimize the biopsy and/or evaluate the evolution of the lesion. When associated, they allow also and perhaps especially to precise the diagnostic, particularly with other tumoral masses such as lymphomas or metastases that can present misleading patterns, but also with other more benign lesions such as abcesses. Always critically analysed, and reevaluated along the time if necesary, they can sometimes help the histological diagnosis, but never can be used in place of it. [Copyright &y& Elsevier]

Abstract: Faunal remains from spoil heaps of two burrows inhabited by small carnivores (fox and badger) are analysed from a taphonomical point of view. This analysis provides characteristics for bone accumulation produced by small carnivores and will be a powerful tool for deciphering site formation about the occupational alternation of small carnivores and humans. Identified species were grouped by size classes. Faunal spectrum is composed by varied species of microfauna (70%), mesofauna (30%). Macromammal remains are under represented (less than 1%) and come from scavenged carcasses. Predators and consumed species are compared on the basis of the skeletal part representation, age classes and recording of predation marks (gnawed and digested bones). Skeletal part representation shows that all taxons exhibit a low-representation of axial skeleton and autopodial bones. Predators show a high representation of hind limb bones and a low representation of the fore limb bones whereas consumed species exhibit a reverse pattern. Mortality curve analysis provides an attritional profile for carnivores and helps for the establishment of the season of occupation of the burrow. Adults largely dominate consumed species. Moreover, predation marks are found in 1% of the carnivores’ bones and from 15% to more than 40% on prey bones. The large-sized prey bones only wear gnawed marks (20%) and anthropic marks (10–20%) whereas microfaunal remains exhibits more digested marks (40%) than gnawing stigmata (5%). Medium-sized animals bones wear both marks and with the same proportions (10–15%). [Copyright &y& Elsevier]

Abstract: We define the notion of triangular (Leray–Koszul) spectral sequence and show that the Jordan spectral invariants of an endomorphism form a triangular spectral sequence. We introduce the concept of a universal coupling between a spectral sequence and a triangular spectral sequence and obtain a second spectral sequence associated to a Massey exact couple. Using these ideas, we construct an example of a spectral sequence which is not derived from an exact couple. To cite this article: B. Bendiffalah, C. R. Acad. Sci. Paris, Ser. I 346 (2008). [Copyright &y& Elsevier]

This study explores the use of Machine Learning techniques for tool condition monitoring in metal machining. Pseudo-local Singular Spectrum Analysis (SSA) of vibration signals raised on the tool holder, coupled to a pass-band filter allowed the definition and the extraction of features which are very sensitive to the tool wear. These features are defined from sums of Fourier coefficients of the signals reconstructed by SSA and of their residues, in judiciously selected frequency bands. The rates of recognition of wear are very good and exceed 80%. This study highlights two important aspects: strong relevance of information in high frequency vibration components and benefits of the combination of SSA and pass-band filtering to get rid of useless components (noise). [ABSTRACT FROM AUTHOR]

Abstract: MRI spectroscopy is a non invasive method for detecting active metabolites used as markers. Chorine and citrate are used for analyzing prostate cancer. MRI spectroscopy combines morphologic imaging and metabolic cartography. This combination allows a new approach for the diagnosis of prostate cancer in patients with negative biopsy and high levels of PSA. With MRI spectroscopy the local staging of prostate cancer has a better accuracy than with MRI alone. It can also be used for the diagnosis of residual disease and recurrence in patients treated with conservative therapy. [Copyright &y& Elsevier]

Abstract: Besson, Courtois and Gallot proved that on a compact manifold, a hyperbolic metric has minimal entropy among the metrics of same volume. Here we show that a hyperbolic metric is a saddle point for the bottom of spectrum of the universal cover. More precisely, the bottom of its spectrum is maximal among the conformal metrics of same volume, and minimal in its Ebin class. [Copyright &y& Elsevier]

Abstract: The frequency analysis of many log data permits to verify that their stochastic component show ‘power-law-type’ spectral densities, characteristic of noise. They can be modelled by fractional Brownian motions. Continuous Wavelet Transformation (CWT) provides us with very efficient methods to determine the local spectral exponents of these scaling laws. These new attributes are related to the local fractality of these signals. We first present some theoretical results and an application to a fractional Brownian motion. The second application concerns a dataset recorded in the MAR203 borehole. We show that clustering of these new pseudo-logs leads to a good resolution between different lithofacies. To cite this article: N. Zaourar et al., C. R. Geoscience 338 (2006). [Copyright &y& Elsevier]

Abstract: We consider a system of a nucleus with an electron together with the quantized electromagnetic field. Instead of fixing the nucleus, the system is confined by its center of mass. This model is used in theoretical physics to explain the Lamb–Dicke and the Mössbauer effects. When an ultraviolet cut-off is imposed we initiate the spectral analysis of the Hamiltonian describing the system and we derive the existence of a ground state. This is achieved without conditions on the fine structure constant. To cite this article: L. Amour, J. Faupin, C. R. Acad. Sci. Paris, Ser. I 343 (2006). [Copyright &y& Elsevier]

Abstract: We propose a new approach for the discretization of diffusive flux on a non orthogonal mesh based on the Deferred correction introduced by Peric. This new method is applied successfully to the solution of a Poisson problem in quadrangular domains meshed with very distorted control volumes. The interest of this approach lies in the fact that the precision of the used schemes is conserved despite meshes distortion level. The comparative study of the value of the spectral radius of iteration matrix enables us to explain why our Deferred correction approach is better than that of Peric, which diverges on highly skewed meshes. To cite this article: Y.M. Ahipo, Ph. Traore, C. R. Mecanique 334 (2006). [Copyright &y& Elsevier]

Abstract: Selective T2 relaxation times measurement of intramyocellular and extramyocellular lipids in Zucker rats at 7 teslas. Several techniques have been used to quantify the concentration of muscular lipids, but they are invasive and cannot quantify accurately lipids inside the muscle cell from lipids outside. In vivo 1H-NMR spectroscopy is used to distinguish the two types of lipids. This technique is based on magnetic susceptibility difference experienced by intramyocellular and extramyocellular lipids. Nevertheless, the quantification of these lipids remains difficult due to lines-widths difference. Thus prior knowledge of the relaxation times of these two types of lipids is important to optimize this quantification. The aim of the present study is to measure transverse relaxation times of intramyocellular and extramyocellular lipids in the Zucker rat at 7 teslas. To cite this article: R. Fissoune et al., C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Abstract: Static and MAS solid-state study of supported phospholipid bilayer cylindrically oriented. Solid-state NMR spectroscopy has been used to investigate a biomimetic model membrane. In this model, the supported bilayers, obtained by fusion of SUVs, are tethered inside nanoporous aluminum oxide supports via a streptavidin/biotin spacer arm. The static and slow Magic-Angle Spinning deuterium NMR spectra of the tethered bilayers have been compared to the experimental and simulated spectra of a simpler model with cylindrical geometry, namely a phospholipid bilayer adsorbed on an oriented polymer (PET) sheet. MAS experimental spectra of both models are in good agreement with the simulated spectrum of an ideal cylindrical distribution of phospholipids. By studying bilayers of DMPC d54, the 2H MAS experiments permit to assess the geometrical arrangement of the lipids inside the nanopores. To cite this article: O. Wattraint, C. Sarazin, C. R. Chimie 9 (2006) . [Copyright &y& Elsevier]

Copyright of Canadian Journal of Chemical Engineering is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multipoles and shifts in the Lyman series of neon. The Lyman spectrum of hydrogenic neon is experimentally obtained from a laser-imploded glass microballoon. Through spatial resolution, hydrodynamic modelling and molecular-dynamics simulations, a comparison with predicted spectral profiles and line merging stresses the importance of such theoretical aspects as plasma polarisation shifts and ionic multipolar effects. [ABSTRACT FROM AUTHOR]

Abstract: Structural characterization and spectroscopic study of charge transfer of two polymorphs of complex (TTF)3(TNF)2, where TTF=tetrathiafulvalene and TNF=2,4,7-trinitro-9-fluorenone. Two polymorphs, α and β, for the charge-transfer complex (TTF)3(TNF)2, with TTF=tetrathiafulvalene and TNF=2,4,7-trinitro-9-fluorenone, have been characterized by X-ray diffraction and infrared spectroscopy. A structural modification of the TNF moiety allows different packing structures. An estimation of the degree of charge transfer establishes that δβ > δα ≈0, a feature consistent with crystalline structures. To cite this article: A. Salmerón-Valverde, S. Bernès, C. R. Chimie 8 (2005). [Copyright &y& Elsevier]

Abstract: Nuclear magnetic spectroscopy (MRS) is a useful method for noninvasively studying intracerebral metabolism. Proton MRS can identify markers of the neuronal viability (N-acetyl-aspartate, NAA), of the metabolism of cellular membranes (choline), of the cellular energy metabolism (creatine, lactate). In Phosphorus MRS, the peaks most readily identified are involved in the high-energy cellular metabolism (ATP, phosphocreatine, inorganic phosphate), and intracellular pH (pHi) can be determined using this method. MRS has been used in experimental models of traumatic brain injury (TBI), primarily to study the cellular metabolism and the relation between biochemical and histological changes after trauma. In trauma patients, significant changes in NAA, choline and pHi were found in both grey and white matter comparing with controls, and these alterations correlated with injury severity. Correlations have been reported between these biochimical changes (reduction in NAA, increase in choline) measured at 1 to 6 months after TBI and the clinical outcome of the patients. However, there are methodological issues which still impede to recommend MRS as a tool for predicting neurological outcome in the clinical setting. [Copyright &y& Elsevier]

Abstract: Different diagenetic transformations and their relative chronological sequence are studied in the meteoric diagenetic zone from the Upper Oligocene limestone at the North of the Aquitaine Basin (France), by combining high-resolution cathodoluminescence spectroscopy and electron-microprobe analyses. More than 128 spot analyses by electron microprobe and 60 analyses by cathodoluminescence spectroscopy are done on different meteoric cements firstly identified by classic optical microscopy. Three cement types are identified according to the relative intensity of the bands of their respective cathodoluminescence spectra (350, 380, 430, 500, and 620 nm). From these investigations, we could identify for each meteoric cement different phases of crystalline growth and crystalline dissolution. As a result, a better and more realistic meteoric diagenetic model is proposed. It illustrates the cyclic transformations from vadose zone (unsaturated) to meteoric zone (saturated). To cite this article: R. Chapoulie et al., C. R. Geoscience 337 (2005). [Copyright &y& Elsevier]

The reaction of β-keto-δ-carbethoxyphosphonates and phosphineoxides 1 with active cyanoarylidenes 2 in basic conditions provides a convenient access to the new 2-amino-6-(phosphonomethyl)-4H-pyranes 3. The reaction is found to be highly regioselective. The structure of all obtained products is confirmed by NMR (¹H, 31P, 13C), IR spectroscopy, and in some cases by mass spectrometry. [ABSTRACT FROM AUTHOR]

Objectives. – To review the literature on chronic exertional compartment syndrome.Methods. – We searched the Medline database with use of the keys words compartment syndrome, exertional, chronic, pressure, and fasciotomy.Results. – Exertional compartment syndrome is characterized by pain on exertion, which recedes at rest, and by excessive increase in compartment intramuscular pressure. Intramuscular pressure measurement is the reference diagnostic tool, but it has not been standardized or evaluated. Pressure observed during the first 5 min after exertion stops is more often used in diagnosis. The first studies of noninvasive investigations (magnetic resonance imaging, thallium single-photon emission tomographic imaging, near infrared spectroscopy) revealed their inadequate diagnostic value. The pathophysiological features of exertional compartment syndrome remain unclear: increased muscle bulk, fascia thickness and stiffness, stimulation of fascial sensory stretch-receptors, poor venous return, micromuscular injuries, and small clinical myopathic abnormalities. Treatment includes decreased sport activity or fasciotomy with partial fasciectomy. Several authors have used endoscopically assisted fasciotomy, which retrospective studies have shown to be successful. Long-term outcome studies could investigate the persistence of exertional minor pain and recurrence of the compartment syndrome with this treatment.Conclusion. – Further studies are required to understand the physiopathology, standardize the intramuscular pressure test and evaluate the pressure threshold values, evaluate noninvasive investigations and specify the long-term outcome of fasciotomy. [Copyright &y& Elsevier]

We build a rate potential through the introduction of several behavior assumptions, of which we discuss the physical meaning. Inserted into the quasi-static equations, this potential allows us to revisit the generic problem of the plastic buckling of the cruciform column. We get an interval on the parameter axis of which any point is a bifurcation point. This result is qualitatively interesting from the point of view of spectral analysis, as the existence of such a continuum was up to now related to discontinuities in the constitutive law, while everything is very smooth in the present case. To cite this article: A. Cimetie`re et al., C. R. Mecanique 332 (2004). [Copyright &y& Elsevier]

In the present article, we discuss the interaction of the spin 0 particule with an Aharanov–Bohm potential of two and three dimensions by the application of the Duffin–Kemmer–Petiau equation. We have calculated and discussed the spectrum of energy and its dependence on the intensity of the Aharonov–Bohm potential. [ABSTRACT FROM AUTHOR]

In this paper, we present a simple method that allows, among other things, to determine the absorption coefficient of X-rays from reflectivity measurements. This method is applicable if the analysed material is deposited on a substrate denser than the material layer, so that the X-rays reflectivity spectra exhibit two well-resolved descents. In such cases, the amplitude of the first descent (characteristic of the material layer) is directly related to the linear absorption coefficient of the material constituting the layer. We have been able to clarify this relationship and apply it successfully for several cases of materials, especially amorphous carbon and silicon. Values of thus obtained mass absorption coefficients are in very good agreement with those tabulated in the literature.[Journal translation] [ABSTRACT FROM AUTHOR]

Let X={X(t)}t∈R be a continuous-time strictly stationary and strongly mixing process. In this paper, we prove in the setting of spectral density estimation, at first, under some hard conditions on the spectral density φX (because of aliasing phenomenon), the uniformly complete convergence of the spectral density estimate from periodic sampling. Afterwards, to overcome aliasing, we consider the sampled process {X(tn)}n∈Z, where {tn} is a stationary point process independent from X. The uniform complete convergence of the spectral estimate based on the discrete time observations {X(tk),tk} is also obtained. The convergence rates are also established. To cite this article: M. Rachdi, C. R. Acad. Sci. Paris, Ser. I 337 (2003). [Copyright &y& Elsevier]

Objectives. – To review current data on the heart rate and blood pressure variability.Data sources. – Search through Medline™ databases of articles in french or english.Data selection. – Original articles and case reports were selected according to their quality and main advances. The articles were analysed in order to obtain current data about the methods of study and clinical application of blood pressure and heart rate variability.Data synthesis. – Various regulatory systems in the cardiovascular system play crucial roles in controlling and assuring adequate perfusion of the peripheral tissues. Among them the baroreceptor reflex is the most important regulatory mechanism in the short-term control of the heart rate and blood pressure, and operates through the autonomic nervous system. The gain of the cardiac baroreflex further referred to, as baroreflex sensitivity is an interesting way to study this system. Unfortunately, with our current knowledge, it is not possible to predict the instantaneous output of the baroreceptor in response to instantaneous changes in input within a frequency range of physiological importance. The fast Fourier transform can describe variables as the sum of elementary oscillatory components and it has been established as practical clinical methods for detecting abnormalities in cardiovascular control. A time–frequency distribution provides an indication of how the spectral energy distribution varies with time and it is an interesting tool in non-stationary data. One of the major motivations behind spectral analysis is the hope that the combination of time–domain and frequency–domain analyses will provide dynamical informations about the relation between blood pressure and heart rate. [Copyright &y& Elsevier]

Objective. – To assess the efficacy of ECG spectral analysis, compared with heart rate (HR) monitoring in the detection of vagal response to surgical stimuli.Methods. – Twenty Asa II–III patients (age: 65 ± 13 years) scheduled for surgery of cerebellopontine angle or implantation of sacral root stimulator were examined. Target controlled infusion of propofol (2–4 μg ml–1) and remifentanil (4 ng ml–1) was guided by the bispectral index (Bis). Arterial pressure via a radial catheter, pulse oximetry and end tidal CO2 were continuously monitored. Spectral analysis was achieved by connecting a computer to the cardiorespiratory monitor. Online power spectrum densities were calculated from the ECG R–R interval by software based on the fast Fourier transform (LabView™, National Instruments, USA). Low frequency (LF: 0.04–0.15Hz) and high frequency (HF: 0.15–0.4Hz) were associated with sympathetic and parasympathetic activities respectively. We defined vagal reaction as a decrease in FC or an increase in HF >10% of the prestimuli value. HF and FC were compared according to the detection delay (by a Student t test with p < 0.05 considered significant) and a concordance test with a kappa coefficient (κ): –1 = total discordance to 1 = total concordance.Results. – Twelve vagal reactions (observed in 8 patients) were detected within 5.5 ± 1.3 s (HF) and 12.4 ± 1.6 (FC) ; p < 0.001. Concordance between the 2 parameters was 95% (κ =0.9).Conclusion. – The ECG spectral analysis is a non-invasive technique, which permits the detection of intra-operative vagal reactions earlier than conventional monitoring of HR. [Copyright &y& Elsevier]

In the first part of this Note, we show that the first non-zero eigenvalue of the Laplace operator on 1-forms of a standard congruence arithmetic complex hyperbolic n-manifold is always &ges;10n−11/25. The following parts of this Note concern homological applications of this result. We prove, in particular, that if Sh0H⊂Sh0G are two Shimura varieties of type U(n−1,1) and U(n,1), the natural map H2n−3(Sh0H)→H2n−3(Sh0G) is injective, first step of a “Lefschetz theorem” for Shimura varieties. To cite this article: N. Bergeron, L. Clozel, C. R. Acad. Sci. Paris, Ser. I 334 (2002) 995–998. [Copyright &y& Elsevier]

Annealing at 400&les;T&les;600 °C (40&les;P&les;60 MPa and HM buffer-controlled f(O2)) of tourmalines synthesised at the same T and P with NNO buffer induces an oxidation of Fe2+ into Fe3+ in some Y sites only (Mo¨ssbauer Spectroscopy data). Annealing in the same conditions of natural tourmalines is consistent with these results. FTIR spectroscopy shows that oxidation of Fe2+ into Fe3+ is charge-balanced by deprotonation of the external OH(3) groups. To cite this article: Y. Fuchs et al., C. R. Geoscience 334 (2002) 245–249. [Copyright &y& Elsevier]

A new synthetic approach to the novel pyrimidine and pyridone is described. The structures of the obtained adducts by opening of dehydroacetic acid ring have been assigned by means of spectroscopic measurements. [ABSTRACT FROM AUTHOR]

La solution analytique de l'équation de transport/relaxation 3-D nous permet d'obtenir le profile des lignes spectrales élargies sous les effets Doppler et de pression. Dans le cadre de l'approximation d'impact, nous tenons compte de la dépendance en vitesse de l'élargissement et du déplacement causés par les collisions élastiques ainsi que du rétrécissement de Dicke dû aux collisions inélastiques. Nous avons utilisé les modèles de Rautian--Sobelman et de Keilson--Storer pour décrire ces dernières. Nous trouvons, dans la limite haute densité ou hydrodynamique, que les deux modèles donnent un profile qui est une somme pondérée de profiles de Lorentz si l'élargissement par collision est plus grand que la fréquence des collisions inélastiques ou un profile de Lorentz ordinaire dans le cas opposé. Ceci démontre que la grandeur relative des sections efficaces optique et cinématique est importante pour déterminer la forme des courbes d'absorption. Les solutions analytiques peuvent ˆtre utiles pour modéliser les courbes d'absorption dans les sondages à distance de l'atmosphère. [ABSTRACT FROM AUTHOR]

Seeds of tomato (Lycopersicum esculentum L. cv. Gribovsky‐1180) and carrot (Daucus carota L. cv. Santanet) were irradiated by continuous light of different wavelengths (white, blue, green, red, far‐red and He‐Ne laser) and different power density. Free radical output was measured using Electron Spin Resonance spectra (ESR). The dependence of the content of free radicals (FR) on the light power density was established. The yield of FR in the seeds irradiated with monochromatic light of the same power density was inversely proportional to the wavelength. The ESR spectra showed maximum absolute number of FR for white light. Successive irradiations gave cumulative effects on the output of free radicals in both directions: increase by the action of white light and decrease by the action of red and far‐red light. The contact of irradiated seeds with steam decreased the amount of FR. [ABSTRACT FROM AUTHOR]