600 research outputs found
Tools for genetic manipulation of the plant growth-promoting bacterium Azospirillum amazonense
<p>Abstract</p> <p>Background</p> <p><it>Azospirillum amazonense </it>has potential to be used as agricultural inoculant since it promotes plant growth without causing pollution, unlike industrial fertilizers. Owing to this fact, the study of this species has gained interest. However, a detailed understanding of its genetics and physiology is limited by the absence of appropriate genetic tools for the study of this species.</p> <p>Results</p> <p>Conjugation and electrotransformation methods were established utilizing vectors with broad host-replication origins (pVS1 and pBBR1). Two genes of interest - <it>glnK </it>and <it>glnB</it>, encoding PII regulatory proteins - were isolated. Furthermore, <it>glnK</it>-specific <it>A. amazonense </it>mutants were generated utilizing the pK19MOBSACB vector system. Finally, a promoter analysis protocol based on fluorescent protein expression was optimized to aid genetic regulation studies on this bacterium.</p> <p>Conclusion</p> <p>In this work, genetic tools that can support the study of <it>A. amazonense </it>were described. These methods could provide a better understanding of the genetic mechanisms of this species that underlie its plant growth promotion.</p
Do patients prefer optimistic or cautious psychiatrists? An experimental study with new and long-term patients
Abstract
Background
Patients seeking treatment may be assumed to prefer a psychiatrist who suggests a new treatment with confidence and optimism. Yet, this might not apply uniformly to all patients. In this study, we tested the hypothesis that new patients prefer psychiatrists who present treatments optimistically, whilst patients with longer-term experience of mental health care may rather prefer more cautious psychiatrists.
Methods
In an experimental study, we produced video-clips of four psychiatrists, each suggesting a pharmacological and a psychological treatment once with optimism and once with caution. 100 \u2018new\u2019 patients with less than 3\ua0months experience of mental health care and 100 \u2018long-term\u2019 patients with more than one year of experience were shown a random selection of one video-clip from each psychiatrist, always including an optimistic and a cautious suggestion of each treatment. Patients rated their preferences for psychiatrists on Likert type scales. Differences in subgroups with different age (18\u201340 vs. 41\u201365 years), gender, school leaving age (\u226416 vs. >16\ua0years), and diagnosis (ICD 10\ua0F2 vs. others) were explored.
Results
New patients preferred more optimistic treatment suggestions, whilst there was no preference among long-term patients. The interaction effect between preference for treatment presentations and experience of patients was significant (interaction p -value\u2009=\u20090.003). Findings in subgroups were similar.
Conclusion
In line with the hypothesis, psychiatrists should suggest treatments with optimism to patients with little experience of mental health care. However, this rule does not apply to longer-term patients, who may have experienced treatment failures in the past
Recommended from our members
The impact of mental health recovery narratives on recipients experiencing mental health problems: Qualitative analysis and change model.
BACKGROUND: Mental health recovery narratives are stories of recovery from mental health problems. Narratives may impact in helpful and harmful ways on those who receive them. The objective of this paper is to develop a change model identifying the range of possible impacts and how they occur. METHOD: Semi-structured interviews were conducted with adults with experience of mental health problems and recovery (n = 77). Participants were asked to share a mental health recovery narrative and to describe the impact of other people's recovery narratives on their own recovery. A change model was generated through iterative thematic analysis of transcripts. RESULTS: Change is initiated when a recipient develops a connection to a narrator or to the events descripted in their narrative. Change is mediated by the recipient recognising experiences shared with the narrator, noticing the achievements or difficulties of the narrator, learning how recovery happens, or experiencing emotional release. Helpful outcomes of receiving recovery narratives are connectedness, validation, hope, empowerment, appreciation, reference shift and stigma reduction. Harmful outcomes are a sense of inadequacy, disconnection, pessimism and burden. Impact is positively moderated by the perceived authenticity of the narrative, and can be reduced if the recipient is experiencing a crisis. CONCLUSIONS: Interventions that incorporate the use of recovery narratives, such as peer support, anti-stigma campaigns and bibliotherapy, can use the change model to maximise benefit and minimise harms from narratives. Interventions should incorporate a diverse range of narratives available through different mediums to enable a range of recipients to connect with and benefit from this material. Service providers using recovery narratives should preserve authenticity so as to maximise impact, for example by avoiding excessive editing
Commissioning of the vacuum system of the KATRIN Main Spectrometer
The KATRIN experiment will probe the neutrino mass by measuring the
beta-electron energy spectrum near the endpoint of tritium beta-decay. An
integral energy analysis will be performed by an electro-static spectrometer
(Main Spectrometer), an ultra-high vacuum vessel with a length of 23.2 m, a
volume of 1240 m^3, and a complex inner electrode system with about 120000
individual parts. The strong magnetic field that guides the beta-electrons is
provided by super-conducting solenoids at both ends of the spectrometer. Its
influence on turbo-molecular pumps and vacuum gauges had to be considered. A
system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter
strips has been deployed and was tested during the commissioning of the
spectrometer. In this paper the configuration, the commissioning with bake-out
at 300{\deg}C, and the performance of this system are presented in detail. The
vacuum system has to maintain a pressure in the 10^{-11} mbar range. It is
demonstrated that the performance of the system is already close to these
stringent functional requirements for the KATRIN experiment, which will start
at the end of 2016.Comment: submitted for publication in JINST, 39 pages, 15 figure
Phylogenetic placement of environmental sequences using taxonomically reliable databases helps to rigorously assess dinophyte biodiversity in Bavarian lakes (Germany).
1. Reliable determination of organisms is a prerequisite to explore their spatial
and temporal occurrence and to study their evolution, ecology, and dispersal. In
Europe, Bavaria (Germany) provides an excellent study system for research on the
origin and diversification of freshwater organisms including dinophytes, due to
the presence of extensive lake districts and ice age river valleys. Bavarian freshwater
environments are ecologically diverse and range from deep nutrient‐poor
mountain lakes to shallow nutrient‐rich lakes and ponds.
2. We obtained amplicon sequence data (V4 region of small subunit‐rRNA, c. 410 bp
long) from environmental samples collected at 11 sites in Upper Bavaria. We
found 186 operational taxonomic units (OTUs) associated with Dinophyceae that
were further classified by means of a phylogenetic placement approach.
3. The maximum likelihood tree inferred from a well‐curated reference alignment comprised
a systematically representative set of 251 dinophytes, covering the currently
known molecular diversity and OTUs linked to type material if possible. Environmental
OTUs were scattered across the reference tree, but accumulated mostly in freshwater
lineages, with 79% of OTUs placed in either Apocalathium, Ceratium, or Peridinium,
the most frequently encountered taxa in Bavaria based on morphology.
4. Twenty‐one Bavarian OTUs showed identical sequences to already known and
vouchered accessions, two of which are linked to type material, namely Palatinus
apiculatus and Theleodinium calcisporum. Particularly within Peridiniaceae, delimitation
of Peridinium species was based on the intraspecific sequence variation.
5. Our approach indicates that high‐throughput sequencing of environmental samples
is effective for reliable determination of dinophyte species in Bavarian lakes.
We further discuss the importance of well‐curated reference databases that remain
to be developed in the future
- …