The Experts below are selected from a list of 10617 Experts worldwide ranked by ideXlab platform
Yannick Moret - One of the best experts on this subject based on the ideXlab platform.
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Social life‐history response to individual immune challenge of workers of Bombus terrestris L.: a possible new Cooperative Phenomenon
Ecology Letters, 2004Co-Authors: Yannick Moret, Paul Schmid-hempelAbstract:Parasites typically reduce host survival or fecundity. To minimize fitness loss, hosts can make temporal adjustments of their reproductive effort. To date such plastic shifts of life-history traits in response to parasitism are only known from solitary organisms where infected individuals can react by themselves. In the case of social insects, where brood care and reproductive effort is shared between reproductive individuals (typically the queen) and workers, adjustments of the reproductive effort would depend on collective decision-making. We tested for this possibility by experimentally activating the immune response of individual workers in colonies of the bumblebee, Bombus terrestris L. This induction resulted, in combination with environmental conditions, in a reduction of fitness of the social unity (i.e. colony success, measured by number and biomass of offspring) and a collective response towards earlier reproduction. As both phenomena are expressed at the level of the colony, the result suggests that key elements of the use of immune defence have been maintained through the evolutionary transition to sociality.
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social life history response to individual immune challenge of workers of bombus terrestris l a possible new Cooperative Phenomenon
Ecology Letters, 2004Co-Authors: Yannick Moret, Paul SchmidhempelAbstract:Parasites typically reduce host survival or fecundity. To minimize fitness loss, hosts can make temporal adjustments of their reproductive effort. To date such plastic shifts of life-history traits in response to parasitism are only known from solitary organisms where infected individuals can react by themselves. In the case of social insects, where brood care and reproductive effort is shared between reproductive individuals (typically the queen) and workers, adjustments of the reproductive effort would depend on collective decision-making. We tested for this possibility by experimentally activating the immune response of individual workers in colonies of the bumblebee, Bombus terrestris L. This induction resulted, in combination with environmental conditions, in a reduction of fitness of the social unity (i.e. colony success, measured by number and biomass of offspring) and a collective response towards earlier reproduction. As both phenomena are expressed at the level of the colony, the result suggests that key elements of the use of immune defence have been maintained through the evolutionary transition to sociality.
Sophia I. Klokishner - One of the best experts on this subject based on the ideXlab platform.
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Modeling the Magnetic Properties and Mössbauer Spectra of Multifunctional Magnetic Materials Obtained by Insertion of a Spin-Crossover Fe(III) Complex into Bimetallic Oxalate-Based Ferromagnets
Inorganic chemistry, 2013Co-Authors: S.m. Ostrovsky, Oleg S. Reu, Andrew Palii, Miguel Clemente-león, Eugenio Coronado, João C. Waerenborgh, Sophia I. KlokishnerAbstract:In this article, we present a theoretical microscopic approach to describe the magnetic and spectroscopic behavior of multifunctional hybrid materials which demonstrate spin crossover and ferromagnetic ordering. The low-spin to high-spin transition is considered as a Cooperative Phenomenon that is driven by the interaction of the electronic shells of the Fe ions with the full symmetric deformation of the local surrounding that is extended over the crystal lattice via the acoustic phonon field. The proposed model is applied to the analysis of the series [FeIII(sal2-trien)] [MnIICrIII(ox)3]·solv, in short 1·solv, where solv = CH2Cl2, CH2Br2, and CHBr3.
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Charge-transfer-induced spin transitions in crystals containing cyanide-bridged Co-Fe clusters: role of intra- and intercluster interactions.
The journal of physical chemistry. A, 2012Co-Authors: Marianna A. Roman, Oleg S. Reu, Sophia I. KlokishnerAbstract:A theoretical model has been developed to explain at the electronic level the charge-transfer-induced spin transition (CTIST) in crystals based on cyano-bridged binuclear Fe–Co clusters. The CTIST is considered as a Cooperative Phenomenon (phase transformation) driven by the long-range electron-deformational interaction via the acoustic phonons field that is taken into account within the mean field approach. The model for CTIST includes also the metal–metal electron transfer and intracluster magnetic exchange. The conditions that favor the CTIST are discussed. The qualitative explanation of the experimental data is given.
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A model of spin crossover in manganese(III) compounds: effects of intra- and intercenter interactions.
Inorganic chemistry, 2011Co-Authors: Sophia I. Klokishner, Marianna A. Roman, Oleg S. ReuAbstract:A microscopic approach to the problem of Cooperative spin crossover in the [MnL2]NO3 crystal, which contains MnIII ions as structural units, is elaborated on, and the main mechanisms governing this effect are revealed. The proposed model also takes into account the splitting of the low-spin 3T1 (t24) and high-spin 5E (t23e) terms by the low-symmetry crystal field. The low-spin → high-spin transition has been considered as a Cooperative Phenomenon driven by interaction of the electronic shells of the MnIII ions with the all-around full-symmetric deformation that is extended over the crystal lattice via the acoustic phonon field. The model well explains the observed thermal dependencies of the magnetic susceptibility and the effective magnetic moment.
Paul Schmid-hempel - One of the best experts on this subject based on the ideXlab platform.
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Social life‐history response to individual immune challenge of workers of Bombus terrestris L.: a possible new Cooperative Phenomenon
Ecology Letters, 2004Co-Authors: Yannick Moret, Paul Schmid-hempelAbstract:Parasites typically reduce host survival or fecundity. To minimize fitness loss, hosts can make temporal adjustments of their reproductive effort. To date such plastic shifts of life-history traits in response to parasitism are only known from solitary organisms where infected individuals can react by themselves. In the case of social insects, where brood care and reproductive effort is shared between reproductive individuals (typically the queen) and workers, adjustments of the reproductive effort would depend on collective decision-making. We tested for this possibility by experimentally activating the immune response of individual workers in colonies of the bumblebee, Bombus terrestris L. This induction resulted, in combination with environmental conditions, in a reduction of fitness of the social unity (i.e. colony success, measured by number and biomass of offspring) and a collective response towards earlier reproduction. As both phenomena are expressed at the level of the colony, the result suggests that key elements of the use of immune defence have been maintained through the evolutionary transition to sociality.
Paul Schmidhempel - One of the best experts on this subject based on the ideXlab platform.
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social life history response to individual immune challenge of workers of bombus terrestris l a possible new Cooperative Phenomenon
Ecology Letters, 2004Co-Authors: Yannick Moret, Paul SchmidhempelAbstract:Parasites typically reduce host survival or fecundity. To minimize fitness loss, hosts can make temporal adjustments of their reproductive effort. To date such plastic shifts of life-history traits in response to parasitism are only known from solitary organisms where infected individuals can react by themselves. In the case of social insects, where brood care and reproductive effort is shared between reproductive individuals (typically the queen) and workers, adjustments of the reproductive effort would depend on collective decision-making. We tested for this possibility by experimentally activating the immune response of individual workers in colonies of the bumblebee, Bombus terrestris L. This induction resulted, in combination with environmental conditions, in a reduction of fitness of the social unity (i.e. colony success, measured by number and biomass of offspring) and a collective response towards earlier reproduction. As both phenomena are expressed at the level of the colony, the result suggests that key elements of the use of immune defence have been maintained through the evolutionary transition to sociality.
Oleg S. Reu - One of the best experts on this subject based on the ideXlab platform.
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Modeling the Magnetic Properties and Mössbauer Spectra of Multifunctional Magnetic Materials Obtained by Insertion of a Spin-Crossover Fe(III) Complex into Bimetallic Oxalate-Based Ferromagnets
Inorganic chemistry, 2013Co-Authors: S.m. Ostrovsky, Oleg S. Reu, Andrew Palii, Miguel Clemente-león, Eugenio Coronado, João C. Waerenborgh, Sophia I. KlokishnerAbstract:In this article, we present a theoretical microscopic approach to describe the magnetic and spectroscopic behavior of multifunctional hybrid materials which demonstrate spin crossover and ferromagnetic ordering. The low-spin to high-spin transition is considered as a Cooperative Phenomenon that is driven by the interaction of the electronic shells of the Fe ions with the full symmetric deformation of the local surrounding that is extended over the crystal lattice via the acoustic phonon field. The proposed model is applied to the analysis of the series [FeIII(sal2-trien)] [MnIICrIII(ox)3]·solv, in short 1·solv, where solv = CH2Cl2, CH2Br2, and CHBr3.
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Charge-transfer-induced spin transitions in crystals containing cyanide-bridged Co-Fe clusters: role of intra- and intercluster interactions.
The journal of physical chemistry. A, 2012Co-Authors: Marianna A. Roman, Oleg S. Reu, Sophia I. KlokishnerAbstract:A theoretical model has been developed to explain at the electronic level the charge-transfer-induced spin transition (CTIST) in crystals based on cyano-bridged binuclear Fe–Co clusters. The CTIST is considered as a Cooperative Phenomenon (phase transformation) driven by the long-range electron-deformational interaction via the acoustic phonons field that is taken into account within the mean field approach. The model for CTIST includes also the metal–metal electron transfer and intracluster magnetic exchange. The conditions that favor the CTIST are discussed. The qualitative explanation of the experimental data is given.
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A model of spin crossover in manganese(III) compounds: effects of intra- and intercenter interactions.
Inorganic chemistry, 2011Co-Authors: Sophia I. Klokishner, Marianna A. Roman, Oleg S. ReuAbstract:A microscopic approach to the problem of Cooperative spin crossover in the [MnL2]NO3 crystal, which contains MnIII ions as structural units, is elaborated on, and the main mechanisms governing this effect are revealed. The proposed model also takes into account the splitting of the low-spin 3T1 (t24) and high-spin 5E (t23e) terms by the low-symmetry crystal field. The low-spin → high-spin transition has been considered as a Cooperative Phenomenon driven by interaction of the electronic shells of the MnIII ions with the all-around full-symmetric deformation that is extended over the crystal lattice via the acoustic phonon field. The model well explains the observed thermal dependencies of the magnetic susceptibility and the effective magnetic moment.