1,418 research outputs found
Apparatus for Dynamical Texture Measurements by Neutron Diffraction Using a Position Sensitive- Detector
Self-trapping of impurities in Bose-Einstein condensates: Strong attractive and repulsive coupling
We study the interaction-induced localization -- the so-called self-trapping
-- of a neutral impurity atom immersed in a homogeneous Bose-Einstein
condensate (BEC). Based on a Hartree description of the BEC we show that --
unlike repulsive impurities -- attractive impurities have a singular ground
state in 3d and shrink to a point-like state in 2d as the coupling approaches a
critical value. Moreover, we find that the density of the BEC increases
markedly in the vicinity of attractive impurities in 1d and 2d, which strongly
enhances inelastic collisions between atoms in the BEC. These collisions result
in a loss of BEC atoms and possibly of the localized impurity itself.Comment: 7 pages, 5 figure
ExB mean flows in finite ion temperature plasmas
The impact of ion pressure dynamics on E x B mean flows is investigated.
Using a simplified, two-dimensional, drift ordered fluid model in the
thin-layer approximation, three stresses in addition to the Reynolds stress are
shown to modify the E x B mean flow. These additional terms in the stress
tensor all require ion pressure fluctuations. Quasi-linear analysis show that
these additional stresses are as important as the Reynolds stress, and hence
must be taken into account in analysis of transport barriers in which sheared E
x B mean flows are key ingredients
Beyond Nanopore Sequencing in Space: Identifying the Unknown
Astronaut Kate Rubins sequenced DNA on the International Space Station (ISS) for the first time in August 2016 (Figure 1A). A 2D sequencing library containing an equal mixture of lambda bacteriophage, Escherichia coli, and Mus musculus was prepared on the ground with a SQK_MAP006 kit and sent to the ISS frozen and loaded into R7.3 flow cells. After a total of 9 on-orbit sequencing runs over 6 months, it was determined that there was no decrease in sequencing performance on-orbit compared to ground controls (1). A total of ~280,000 and ~130,000 reads generated on-orbit and on the ground, respectively, identified 90% of reads that were attributed to 30% lambda bacteriophage, 30% Escherichia coli, and 30% M. musculus (Figure 1B). Extensive bioinformatics analysis determined comparable 2D and 1D read accuracies between flight and ground runs (Figure 1C), and data collected from the ISS were able to construct directed assemblies of E.coli and lambda genomes at 100% and M. musculus mitochondrial genome at 96.7%. These findings validate sequencing as a viable option for potential on-orbit applications such as environmental microbial monitoring and disease diagnosis. Current microbial monitoring of the ISS applies culture-based techniques that provide colony forming unit (CFU) data for air, water, and surface samples. The identity of the cultured microorganisms in unknown until sample return and ground-based analysis, a process that can take up to 60 days. For sequencing to benefit ISS applications, spaceflight-compatible sample preparation techniques are required. Subsequent to the testing of the MinION on-orbit, a sample-to-sequence method was developed using miniPCR and basic pipetting, which was only recently proven to be effective in microgravity. The work presented here details the in- flight sample preparation process and the first application of DNA sequencing on the ISS to identify unknown ISS-derived microorganisms
Ultrastrong Stationary Double Layers in a Nondischarge Magnetoplasma
application/pdf学術論文 (Article)719987 bytesjournal articl
Dysregulation of FGFR signalling by a selective inhibitor reduces germ cell survival in human fetal gonads of both sexes and alters the somatic niche in fetal testes
A novel numerical framework for self-similarity in plasticity: Wedge indentation in single crystals
High-grade cervical intraepithelial neoplasia in human papillomavirus self-sampling of screening non-attenders
The comprehensive cohort model in a pilot trial in orthopaedic trauma
Background: The primary aim of this study was to provide an estimate of effect size for the functional outcome of
operative versus non-operative treatment for patients with an acute rupture of the Achilles tendon using
accelerated rehabilitation for both groups of patients. The secondary aim was to assess the use of a
comprehensive cohort research design (i.e. a parallel patient-preference group alongside a randomised group) in
improving the accuracy of this estimate within an orthopaedic trauma setting.
Methods: Pragmatic randomised controlled trial and comprehensive cohort study within a level 1 trauma centre.
Twenty randomised participants (10 operative and 10 non-operative) and 29 preference participants (3 operative
and 26 non-operative). The ge range was 22-72 years and 37 of the 52 patients were men. All participants had an
acute rupture of their Achilles tendon and no other injuries. All of the patients in the operative group had a simple
end-to-end repair of the tendon with no augmentation. Both groups then followed the same eight-week
immediate weight-bearing rehabilitation programme using an off-the-shelf orthotic. The disability rating index (DRI;
primary outcome), EQ-5D, Achilles Total Rupture Score and complications were assessed ed at two weeks, six
weeks, three months, six months and nine months after initial injury.
Results: At nine months, there was no significant difference in DRI between patients randomised to operative or
non-operative management. There was no difference in DRI between the randomised group and the parallel
patient preference group. The use of a comprehensive cohort of patients did not provide useful additional
information as to the treatment effect size because the majority of patients chose non-operative management.
Conclusions: Recruitment to clinical trials that compare operative and non-operative interventions is notoriously
difficult; especially within the trauma setting. Including a parallel patient preference group to create a
comprehensive cohort of patients has been suggested as a way of increasing the power of such trials. In our
study, the comprehensive cohort model doubled the number of patients involved in the study. However, a strong
preference for non-operative treatment meant that the increased number of patients did not significantly increase
the ability of the trial to detect a difference between the two interventions
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