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Are Investors Warned by Disclosure of Conflicts of Interest? The Moderating Effect of Investment Horizon
Financial analysts are required to disclose conflicts of interest (COI) in their research reports, but there is limited evidence on the effectiveness of COI disclosures. We investigate whether the influence of disclosing COI in analyst reports on investors' decision making depends on investment horizon. Experimental results show that short-term investors who view a COI disclosure are significantly less willing to invest in the recommended stock compared to short-term investors who do not view such a disclosure, while the presence of a COI disclosure does not significantly affect long-term investors’ willingness to invest. Results further demonstrate that the COI disclosure decreases short-term investors’ willingness to invest by reducing their perception of analysts’ trustworthiness and expertness. This study provides evidence on when and how the COI disclosure can influence investors’ behavior and enhances our understanding of investors’ reactions to cautionary disclaimers
The Community of Inquiry Framework Ten Years Later: Introduction to the Special Issue
This article introduces the special issue on the Community of Inquiry (CoI) framework which is being published ten years after the model was first introduced. Since that time the CoI framework has been used to guide and inform both research and practice worldwide. We are very honored to have articles by the original three authors of the CoI model in this special issue. The special issue also contains articles by leading CoI researchers as well as some scholars who are just beginning to use the framework
Why do homeowners renovate energy efficiently?:Contrasting perspectives and implications for policy
This paper contrasts two perspectives on energy efficient home renovations from applied behavioural research on energy efficiency and from sociological research on homes and domestic life. Applied behavioural research characterises drivers and barriers to cost-effective renovations, and identifies personal and contextual influences on homeowners' renovation decisions. Research findings inform policies to promote energy efficiency by removing barriers or strengthening decision influences. Sociological research on domestic life points to limitations in this understanding of renovation decision making that emphasises houses but not homes, energy efficiency but not home improvements, the one-off but not the everyday, and renovations but not renovating. The paper proposes a situated approach in response to this critique. A situated approach retains a focus on renovation decision making, but conceptualises decisions as processes that emerge from the conditions of everyday domestic life and are subject to different levels of influence. This situated approach is tractable for energy efficiency policy while recognising the ultimate influences that explain why homeowners decide to renovate
Wolbachia and DNA barcoding insects: patterns, potential and problems
Wolbachia is a genus of bacterial endosymbionts that impacts the breeding systems of their hosts. Wolbachia can confuse the patterns of mitochondrial variation, including DNA barcodes, because it influences the pathways through which mitochondria are inherited. We examined the extent to which these endosymbionts are detected in routine DNA barcoding, assessed their impact upon the insect sequence divergence and identification accuracy, and considered the variation present in Wolbachia COI. Using both standard PCR assays (Wolbachia surface coding protein – wsp), and bacterial COI fragments we found evidence of Wolbachia in insect total genomic extracts created for DNA barcoding library construction. When >2 million insect COI trace files were examined on the Barcode of Life Datasystem (BOLD) Wolbachia COI was present in 0.16% of the cases. It is possible to generate Wolbachia COI using standard insect primers; however, that amplicon was never confused with the COI of the host. Wolbachia alleles recovered were predominantly Supergroup A and were broadly distributed geographically and phylogenetically. We conclude that the presence of the Wolbachia DNA in total genomic extracts made from insects is unlikely to compromise the accuracy of the DNA barcode library; in fact, the ability to query this DNA library (the database and the extracts) for endosymbionts is one of the ancillary benefits of such a large scale endeavor – for which we provide several examples. It is our conclusion that regular assays for Wolbachia presence and type can, and should, be adopted by large scale insect barcoding initiatives. While COI is one of the five multi-locus sequence typing (MLST) genes used for categorizing Wolbachia, there is limited overlap with the eukaryotic DNA barcode region
Barcoding of the cytochrome oxidase I (COI) indicates a recent introduction of Ciona savignyi into New Zealand and provides a rapid method for Ciona species discrimination
Mitochondrial cytochrome oxidase I (COI) gene sequencing (DNA barcoding) of Ciona specimens from New Zealand (NZ) led to the first record of the solitary ascidian Ciona savignyi in the Southern Hemisphere. We sought to quantify C. savignyi COI genetic diversity around the NZ archipelago and to compare this with diversity within C. savignyi's native range in the north-west Pacific. Ciona savignyi specimens were collected from two NZ sites and from three sites around Japan. COI sequences (595 bp) were amplified and measures of genetic diversity were calculated. Based on differences between their COI sequences we developed a PCR-based assay to distinguish C. savignyi from the morphologically similar C. intestinalis. A total of 12 C. savignyi COI haplotypes were recovered from the 76 samples. Of the four haplotypes observed in NZ, two were unique. From the 10 haplotypes observed in the Japan samples, eight were unique. The C. savignyi populations in Japan were found to contain higher haplotype diversity when compared with those in NZ. The NZ samples contained only a small subset of the haplotype variation of the Japan samples, however, NZ samples did harbor two haplotypes not observed in the Japan samples. A PCR-based assay developed from the COI sequences was able to reliably discriminate the two Ciona species. The low COI genetic diversity within the two NZ C. savignyi populations sampled is consistent with a founder effect associated loss of genetic diversity. The robust PCR-based assay for distinguishing C. savignyi and C. intestinalis may find application in ecological and taxonomic studies and can be applied to both archival materials and live animals
Testing use of mitochondrial COI sequences for the identification and phylogenetic analysis of New Zealand caddisflies (Trichoptera)
We tested the hypothesis that cytochrome c oxidase subunit 1 (COI) sequences would successfully discriminate recognised species of New Zealand caddisflies. We further examined whether phylogenetic analyses, based on the COI locus, could recover currently recognised superfamilies and suborders. COI sequences were obtained from 105 individuals representing 61 species and all 16 families of Trichoptera known from New Zealand. No sequence sharing was observed between members of different species, and congeneric species showed from 2.3 to 19.5% divergence. Sequence divergence among members of a species was typically low (mean = 0.7%; range 0.0–8.5%), but two species showed intraspecific divergences in excess of 2%. Phylogenetic reconstructions based on COI were largely congruent with previous conclusions based on morphology, although the sequence data did not support placement of the purse-cased caddisflies (Hydroptilidae) within the uncased caddisflies, and, in particular, the Rhyacophiloidea. We conclude that sequence variation in the COI gene locus is an effective tool for the identification of New Zealand caddisfly species, and can provide preliminary phylogenetic inferences. Further research is needed to ascertain the significance of the few instances of high intra-specific divergence and to determine if any instances of sequence sharing will be detected with larger sample sizes
Identification of Birds through DNA Barcodes
Short DNA sequences from a standardized region of the genome provide a DNA barcode for identifying species. Compiling a public library of DNA barcodes linked to named specimens could provide a new master key for identifying species, one whose power will rise with increased taxon coverage and with faster, cheaper sequencing. Recent work suggests that sequence diversity in a 648-bp region of the mitochondrial gene, cytochrome c oxidase I (COI), might serve as a DNA barcode for the identification of animal species. This study tested the effectiveness of a COI barcode in discriminating bird species, one of the largest and best-studied vertebrate groups. We determined COI barcodes for 260 species of North American birds and found that distinguishing species was generally straightforward. All species had a different COI barcode(s), and the differences between closely related species were, on average, 18 times higher than the differences within species. Our results identified four probable new species of North American birds, suggesting that a global survey will lead to the recognition of many additional bird species. The finding of large COI sequence differences between, as compared to small differences within, species confirms the effectiveness of COI barcodes for the identification of bird species. This result plus those from other groups of animals imply that a standard screening threshold of sequence difference (10× average intraspecific difference) could speed the discovery of new animal species. The growing evidence for the effectiveness of DNA barcodes as a basis for species identification supports an international exercise that has recently begun to assemble a comprehensive library of COI sequences linked to named specimens
Photoinduced charge and spin dynamics in strongly correlated electron systems
Motivated by photoinduced phase transition in manganese oxides, charge and
spin dynamics induced by photoirradiation are examined. We calculate the
transient optical absorption spectra of the extended double-exchange model by
the density matrix renormalization group (DMRG) method. A charge-ordered
insulating (COI) state becomes metallic just after photoirradiation, and the
system tends to recover the initial COI state. The recovery is accompanied with
remarkable suppression of an antiferromagnetic correlation in the COI state.
The DMRG results are consistent with recent pump-probe spectroscopy data.Comment: 5 pages, 4 figure
Genetic Variation of MtDNA Cytochrome Oxidase Subunit I (COI) in Local Swamp Buffaloes in Indonesia
The objective of this research was to identify genetic variation of mitochondria DNA especially in cytochrome oxidase subunit I (COI) among population of Indonesian buffaloes. Samples of swamp buffaloes were collected from Aceh (n= 3), North Sumatra (n= 3), Riau (n= 3), Banten (n= 3), Central Java (n= 3), West Nusa Tenggara (n= 3) and South Sulawesi (n= 3), and riverine buffalo from North Sumatra (n= 1) out of group for comparison. Sequence of COI was analyzed using MEGA 5.10 software with neighbor-joining method kimura 2-parameter model to reconstruct phylogeny tree. The result showed that three haplotypes for swamp buffalo and one haplotype for riverine buffalo in Indonesia resulted from 41 polymorphic sites. This finding showed that the COI gene could be considered as a marker to distinguish among swamp buffaloes in Indonesia
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