1,178 research outputs found
Unconventional lateral gene transfer in extreme thermophilic bacteria
Conjugation and natural competence are two major mechanisms that explain the acquisition of foreign genes throughout bacterial evolution. In recent decades, several studies in model organisms have revealed in great detail the steps involved in such processes. The findings support the idea that the major basis of these mechanisms is essentially similar in all bacteria. However, recent work has pinpointed the existence of new, evolutionarily different processes underlying lateral gene transfer. In Thermus thermophilus HB27, at least 16 proteins are required for the activity of one of the most efficient natural competence systems known so far. Many of those proteins have no similarities to proteins involved in natural competence in other well-known models. This unusual competence system is conserved, in association with the chromosome, in all other Thermus spp. genomes so far available, it being functional even in strains from isolated environments, such as deep mines. Conjugation is also possible among Thermus spp. Homologues to proteins implicated in conjugation in model bacteria are encoded in the genome of a recently sequenced strain of Thermus thermophilus and shared by other members of the genus. Nevertheless, processive DNA transfer in the absence of a functional natural competence system in strains in which no conjugation homologous genes can be found hints at the existence of an additional and unconventional conjugation mechanism in these bacteriaThis work was supported by grant BIO2010-18875 from the Spanish Ministry of Science and Innovation. An institutional grant from Ramón Areces Foundation to CBMSO is acknowledged. CEC holds a Juan de la Cierva postdoctoral contract from the Spanish Ministry of Science and Innovation. CB and LA are founded by FPI and JAE fellowships from the Ministry of Education and the Spanish National Research Council (CSIC),
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Unconventional lateral gene transfer in extreme thermophilic bacteria
Conjugation and natural competence are two major mechanisms that explain the acquisition of foreign genes throughout bacterial evolution. In recent decades, several studies in model organisms have revealed in great detail the steps involved in such processes. The findings support the idea that the major basis of these mechanisms is essentially similar in all bacteria. However, recent work has pinpointed the existence of new, evolutionarily different processes underlying lateral gene transfer. In Thermus thermophilus HB27, at least 16 proteins are required for the activity of one of the most efficient natural competence systems known so far. Many of those proteins have no similarities to proteins involved in natural competence in other well-known models. This unusual competence system is conserved, in association with the chromosome, in all other Thermus spp. genomes so far available, it being functional even in strains from isolated environments, such as deep mines. Conjugation is also possible among Thermus spp. Homologues to proteins implicated in conjugation in model bacteria are encoded in the genome of a recently sequenced strain of Thermus thermophilus and shared by other members of the genus. Nevertheless, processive DNA transfer in the absence of a functional natural competence system in strains in which no conjugation homologous genes can be found hints at the existence of an additional and unconventional conjugation mechanism in these bacteria
Audio observation of a Wellington Tree Wētā Hemideina crassidens defence stridulation
Wellington Tree Wētā Hemideina crassidens are known to produce a stridulating sound during defence (Field 1982). No papers that I could find have presented publicly available audio files which include this sound. Here, I describe one such call, and encourage others to upload their observations to community science websites
Speech and language therapists’ perspectives of therapeutic alliance construction and maintenance in aphasia rehabilitation post stroke
Background: Therapeutic alliance refers to the interactional and relational processes operating during therapeutic interventions. It been shown to be a strong determinant of treatment efficacy in psychotherapy and evidence is emerging from a range of healthcare and medical disciplines to suggest that the construct of therapeutic alliance may in fact be a variable component of treatment outcome, engagement and satisfaction. Although this construct appears to be highly relevant to aphasia rehabilitation, no research to date has attempted to explore this phenomenon and thus consider its potential utility as a mechanism for change.
Aims: This novel study aims to explore speech and language therapists’ perceptions and experiences of developing and maintaining therapeutic alliances in aphasia rehabilitation post stroke.
Methods & Procedures: Twenty two, in-depth, semi-structured interviews were conducted with speech and language therapists working with people with aphasia post stroke. Qualitative data were analysed using inductive thematic analysis.
Outcomes & Results: Analysis resulted in the emergence of three overarching themes: 1) laying the groundwork; 2) augmenting cohesion; and, 3) contextual shapers. Recognising personhood, developing shared expectations of therapy and establishing therapeutic ownership were central to laying the groundwork for therapeutic delivery. Augmenting cohesion was perceived to be dependent on the therapists’ responsiveness and ability to resolve both conflict and resistance, as part of an ongoing active process. These processes were further moulded by contextual shapers such as the patient’s family, relational continuity and organisational drivers.
Conclusions & Implications: The findings suggest that therapists used multiple, complex relational strategies to establish and manage alliances with people with aphasia, which were reliant on a fluid interplay of verbal and non-verbal skills. The data highlight the need for further training to support therapists to forge purposive alliances. Training should develop: therapeutic reflexivity; inclusivity in goal setting, relational strategies and motivational enhancement techniques. The conceptualisation of therapeutic alliance, however, is only provisional. Further research is essential to elucidate the experiences and perceptions of alliance development for people with aphasia undergoing rehabilitation
Laboratory Development
This research was sponsored by the National Science Foundation Grant NSF PHy 87-1440
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