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Specimens of the genus Orobdella Oka, 1895 from Kunashir Island, the Kuril Islands, are identified as Orobdella kawakatsuorum Richardson, 1975. Mitochondrial tRNA[Leu] and ND1 data confirm the species identification of the Kunashir specimens. This is the first record of the genus Orobdella from the Kuril Islands.

Structural and magnetic properties have been studied in perovskite Nd1-xErxMnO3 (0 ≤ x ≤ 0.5). Er3+ doping enhances the Jahn-Teller distortion, strongly affects the Nd3+-Mn3+ interaction, destroys the intermediate state below the antiferromagnetic transition temperature in NdMnO3, and breaks the antiparallel arrangement between Nd3+ and Mn3+ spin ordering. The decreasing ferromagnetic component in magnetic hysteresis loops at 30 K indicates that the canted angles vary with x. These results offer strong evidence for the interaction between rare earth ions and transition metal ions and competition among rare earth ions as well.

Structural and magnetic properties have been studied in perovskite Nd1-xErxMnO3 (0 ≤ x ≤ 0.5). Er3+ doping enhances the Jahn-Teller distortion, strongly affects the Nd3+-Mn3+ interaction, destroys the intermediate state below the antiferromagnetic transition temperature in NdMnO3, and breaks the antiparallel arrangement between Nd3+ and Mn3+ spin ordering. The decreasing ferromagnetic component in magnetic hysteresis loops at 30 K indicates that the canted angles vary with x. These results offer strong evidence for the interaction between rare earth ions and transition metal ions and competition among rare earth ions as well.

Structural and magnetic properties have been studied in perovskite Nd1-xErxMnO3 (0 ≤ x ≤ 0.5). Er3+ doping enhances the Jahn-Teller distortion, strongly affects the Nd3+-Mn3+ interaction, destroys the intermediate state below the antiferromagnetic transition temperature in NdMnO3, and breaks the antiparallel arrangement between Nd3+ and Mn3+ spin ordering. The decreasing ferromagnetic component in magnetic hysteresis loops at 30 K indicates that the canted angles vary with x. These results offer strong evidence for the interaction between rare earth ions and transition metal ions and competition among rare earth ions as well.

Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La doping. The heat capacity of Nd1−xLaxCrO3 measured from 2 to 300 K reveals that the lattice, electronic, and magnetic contributions to heat capacity can be well interpreted quantitatively using the Debye and Schottky models. The splitting energy of the Cr3+ 3dt2g orbital and the Nd3+ ground state have been calculated by fitting to the Schottky anomaly at very low temperature. The Cr–Nd interaction is suppressed gradually by La doping, which is verified by the calculation of the mean-field interaction parameter. This doping dependence provides directed evidence of TM–RE magnetic interactions in perovskite compounds, in agreement with the proposed model.

Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La doping. The heat capacity of Nd1−xLaxCrO3 measured from 2 to 300 K reveals that the lattice, electronic, and magnetic contributions to heat capacity can be well interpreted quantitatively using the Debye and Schottky models. The splitting energy of the Cr3+ 3dt2g orbital and the Nd3+ ground state have been calculated by fitting to the Schottky anomaly at very low temperature. The Cr–Nd interaction is suppressed gradually by La doping, which is verified by the calculation of the mean-field interaction parameter. This doping dependence provides directed evidence of TM–RE magnetic interactions in perovskite compounds, in agreement with the proposed model.

Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La doping. The heat capacity of Nd1−xLaxCrO3 measured from 2 to 300 K reveals that the lattice, electronic, and magnetic contributions to heat capacity can be well interpreted quantitatively using the Debye and Schottky models. The splitting energy of the Cr3+ 3dt2g orbital and the Nd3+ ground state have been calculated by fitting to the Schottky anomaly at very low temperature. The Cr–Nd interaction is suppressed gradually by La doping, which is verified by the calculation of the mean-field interaction parameter. This doping dependence provides directed evidence of TM–RE magnetic interactions in perovskite compounds, in agreement with the proposed model.

Perovskite-type Nd1−xLaxCrO3(0 ≤ x ≤1.0) polycrystalline samples were synthesized using solid state reaction. Structural studies indicate that the lattice parameters, metal–oxygen bond lengths, and angles of Nd1−xLaxCrO3 strongly depend on the La content. Two magnetic transition temperatures, Cr3+ antiferromagnetic ordering temperature (TN) and the spin reorientation phase transition temperature (TSRPT), have been observed in the M-T curves. The increase in TN and decrease in TSRPT with increasing x value can be explained by the change in the magnetic interactions due to La doping. The heat capacity of Nd1−xLaxCrO3 measured from 2 to 300 K reveals that the lattice, electronic, and magnetic contributions to heat capacity can be well interpreted quantitatively using the Debye and Schottky models. The splitting energy of the Cr3+ 3dt2g orbital and the Nd3+ ground state have been calculated by fitting to the Schottky anomaly at very low temperature. The Cr–Nd interaction is suppressed gradually by La doping, which is verified by the calculation of the mean-field interaction parameter. This doping dependence provides directed evidence of TM–RE magnetic interactions in perovskite compounds, in agreement with the proposed model.

Poly(ADP)ribose (PAR) metabolism is essential to many cellular functions, including the maintenance of genomic integrity, the regulation of cell death mechanisms, as well as the regulation of gene expression. Recent work has uncovered many new players in the expanding effort to understand PAR metabolism and its cellular impact. PARP-1, the prototypical poly(ADP)ribose polymerase, was the first to be discovered, and has since been shown to be vital in the cellular response to DNA damage. Indeed, one report demonstrating that PARP-1 activation is required for apoptosis-inducing factor (AIF) release from mitochondria uncovered a novel link between DNA damage and signaling for cell death. The events following PARP activation, leading to signaling for AIF release, however, are still poorly understood. Based on our observations, we have developed a model to explain the nuclear/mitochondrial crosstalk that occurs following PARP activation. The work presented here answers several important questions regarding the relationship between ADP-ribose metabolism and mitochondria, including the role of PAR in signaling for the release of AIF, the presence of ADP-ribose metabolism protein members in mitochondria, and mitochondrial transcriptional effects following PARP activation. This work presents several novel findings, including the first report of a mitochondrial matrix isoform of poly(ADP-ribose) glycohydrolase (PARG) as well as direct evidence of mitochondria-associated PARP activity. Furthermore, it provides evidence for a novel effect of PARP-1 activation, in the specific transcriptional upregulation of the mitochondrial gene, NADH dehydrogenase, subunit 1 (ND1). Our data is consistent with the hypothesis that uncontrolled PARP activity results in energy metabolism dysfunction and cell death. Furthermore, it supports a model in which PARP activity is required for normal transcriptional responses in mitochondria following DNA damage. In total, this report adds to the body of

Genetic divergence in bat communities was assessed on both sides of the Straits of Gibraltar and cryptic diversity was examined. Screening was carried out using partial sequences of the mitochondrial (mt)DNA cytochrome b gene on 399 individual bats belonging to the 18 species found on both sides of the Straits of Gibraltar. For those bats that showed important genetic discontinuities, molecular markers (ND1 and nuclear RAG2 genes) were added to expand the sampling process. Phylogenetic reconstructions were obtained using maximum parsinomy, genetic distances, maximum likelihood, and Bayesian criteria. As an estimate of bats’ flight performance, we measured for each species the wing aspect ratio and wing loading indexes, and correlated them with the maximum pairwise genetic distances obtained between southern Iberian and northern Moroccan populations. Genetic mtDNA distances between populations on both continents exceed 5% in seven out of 18 bat species analysed and unknown lineages were uncovered within the species complexes Myotis nattereri and Myotis mystacinus. We did not find a general pattern in the degree of permeability of the Straits of Gibraltar for bats. Genetic distances were not correlated with the ability to cross the Straits. Our study shows that the cryptic diversity uncovered among bats continues to increase as more regions are studied.

© 2007 The Author et al. This is an open-access article distributed under the terms of the Creative Commons 2.5 Attribution License. The definitive version was published in Proceedings of The Royal Society B 275 (2008): 237-247, doi:10.1098/rspb.2007.1290., DNA barcoding has become a promising means for identifying organisms of all life stages. Currently, phenetic approaches and tree-building methods have been used to define species boundaries and discover 'cryptic species'. However, a universal threshold of genetic distance values to distinguish taxonomic groups cannot be determined. As an alternative, DNA barcoding approaches can be 'character based', whereby species are identified through the presence or absence of discrete nucleotide substitutions (character states) within a DNA sequence. We demonstrate the potential of character-based DNA barcodes by analysing 833 odonate specimens from 103 localities belonging to 64 species. A total of 54 species and 22 genera could be discriminated reliably through unique combinations of character states within only one mitochondrial gene region (NADH dehydrogenase 1). Character-based DNA barcodes were further successfully established at a population level discriminating seven population-specific entities out of a total of 19 populations belonging to three species. Thus, for the first time, DNA barcodes have been found to identify entities below the species level that may constitute separate conservation units or even species units. Our findings suggest that character-based DNA barcoding can be a rapid and reliable means for (i) the assignment of unknown specimens to a taxonomic group, (ii) the exploration of diagnosability of conservation units, and (iii) complementing taxonomic identification systems., The work was supported by the Federal Government Research Program (BMBF) BIOTA South Africa (S08) and the German Science Foundation (DFG) Special Priority Program 'Deep Metazoan Phylogeny' SP1174 (DFG HA 1947/5-1 and 5-2); grants given to the last author.

© 2007 The Author et al. This is an open-access article distributed under the terms of the Creative Commons 2.5 Attribution License. The definitive version was published in Proceedings of The Royal Society B 275 (2008): 237-247, doi:10.1098/rspb.2007.1290., DNA barcoding has become a promising means for identifying organisms of all life stages. Currently, phenetic approaches and tree-building methods have been used to define species boundaries and discover 'cryptic species'. However, a universal threshold of genetic distance values to distinguish taxonomic groups cannot be determined. As an alternative, DNA barcoding approaches can be 'character based', whereby species are identified through the presence or absence of discrete nucleotide substitutions (character states) within a DNA sequence. We demonstrate the potential of character-based DNA barcodes by analysing 833 odonate specimens from 103 localities belonging to 64 species. A total of 54 species and 22 genera could be discriminated reliably through unique combinations of character states within only one mitochondrial gene region (NADH dehydrogenase 1). Character-based DNA barcodes were further successfully established at a population level discriminating seven population-specific entities out of a total of 19 populations belonging to three species. Thus, for the first time, DNA barcodes have been found to identify entities below the species level that may constitute separate conservation units or even species units. Our findings suggest that character-based DNA barcoding can be a rapid and reliable means for (i) the assignment of unknown specimens to a taxonomic group, (ii) the exploration of diagnosability of conservation units, and (iii) complementing taxonomic identification systems., The work was supported by the Federal Government Research Program (BMBF) BIOTA South Africa (S08) and the German Science Foundation (DFG) Special Priority Program 'Deep Metazoan Phylogeny' SP1174 (DFG HA 1947/5-1 and 5-2); grants given to the last author.

© 2007 The Author et al. This is an open-access article distributed under the terms of the Creative Commons 2.5 Attribution License. The definitive version was published in Proceedings of The Royal Society B 275 (2008): 237-247, doi:10.1098/rspb.2007.1290., DNA barcoding has become a promising means for identifying organisms of all life stages. Currently, phenetic approaches and tree-building methods have been used to define species boundaries and discover 'cryptic species'. However, a universal threshold of genetic distance values to distinguish taxonomic groups cannot be determined. As an alternative, DNA barcoding approaches can be 'character based', whereby species are identified through the presence or absence of discrete nucleotide substitutions (character states) within a DNA sequence. We demonstrate the potential of character-based DNA barcodes by analysing 833 odonate specimens from 103 localities belonging to 64 species. A total of 54 species and 22 genera could be discriminated reliably through unique combinations of character states within only one mitochondrial gene region (NADH dehydrogenase 1). Character-based DNA barcodes were further successfully established at a population level discriminating seven population-specific entities out of a total of 19 populations belonging to three species. Thus, for the first time, DNA barcodes have been found to identify entities below the species level that may constitute separate conservation units or even species units. Our findings suggest that character-based DNA barcoding can be a rapid and reliable means for (i) the assignment of unknown specimens to a taxonomic group, (ii) the exploration of diagnosability of conservation units, and (iii) complementing taxonomic identification systems., The work was supported by the Federal Government Research Program (BMBF) BIOTA South Africa (S08) and the German Science Foundation (DFG) Special Priority Program 'Deep Metazoan Phylogeny' SP1174 (DFG HA 1947/5-1 and 5-2); grants given to the last author.

Morphological features and mitochondrial DNA (mtDNA) sequences were analysed to study the phylogenetic relationships among eight species of whiskered bats (genus Myotis, subgenus Selysius) in the Palaearctic region. The mtDNA phylogeny did not support the current division of the subgenus into species groups based on morphological data and species distributions, but showed instead that several species in the subgenus Selysius originated from distant lineages. The morphological similarity in some species could be due to convergence as a result of adaptation to similar habitats., International Symposium on "Dawn of a New Natural History - Integration of Geoscience and Biodiversity Studies". 5-6 March 2004. Sapporo, Japan.

International Symposium on "Dawn of a New Natural History - Integration of Geoscience and Biodiversity Studies". 5-6 March 2004. Sapporo, Japan., Morphological features and mitochondrial DNA (mtDNA) sequences were analysed to study the phylogenetic relationships among eight species of whiskered bats (genus Myotis, subgenus Selysius) in the Palaearctic region. The mtDNA phylogeny did not support the current division of the subgenus into species groups based on morphological data and species distributions, but showed instead that several species in the subgenus Selysius originated from distant lineages. The morphological similarity in some species could be due to convergence as a result of adaptation to similar habitats.

Morphological features and mitochondrial DNA (mtDNA) sequences were analysed to study the phylogenetic relationships among eight species of whiskered bats (genus Myotis, subgenus Selysius) in the Palaearctic region. The mtDNA phylogeny did not support the current division of the subgenus into species groups based on morphological data and species distributions, but showed instead that several species in the subgenus Selysius originated from distant lineages. The morphological similarity in some species could be due to convergence as a result of adaptation to similar habitats., International Symposium on "Dawn of a New Natural History - Integration of Geoscience and Biodiversity Studies". 5-6 March 2004. Sapporo, Japan.