1,544 research outputs found
Local classification of twodimensional affine spheres with constant curvature metric
AbstractWe extend results of Radon, Li-Penn and Magid-Ryan and give a local classification of affine spheres with constant curvature metric in affine 3-space
Complete Genome Sequence of Bacteroides ovatus V975
The complete genome sequence of Bacteroides ovatus V975 was determined. The genome consists of a single circular chromosome of 6,475,296 bp containing five rRNA operons, 68 tRNA genes, and 4,959 coding genes
Use of genetically modified bacteria for drug delivery in humans: Revisiting the safety aspect
The use of live, genetically modified bacteria as delivery vehicles for biologics is of considerable interest scientifically and has attracted significant commercial investment. We have pioneered the use of the commensal gut bacterium Bacteroides ovatus for the oral delivery of therapeutics to the gastrointestinal tract. Here we report on our investigations of the biological safety of engineered B. ovatus bacteria that includes the use of thymineless death as a containment strategy and the potential for the spread of transgenes in vivo in the mammalian gastrointestinal tract. We demonstrate the ability of GM-strains of Bacteroides to survive thymine starvation and overcome it through the exchange of genetic material. We also provide evidence for horizontal gene transfer in the mammalian gastrointestinal tract resulting in transgene-carrying wild type bacteria. These findings sound a strong note of caution on the employment of live genetically modified bacteria for the delivery of biologics
Quantization of Curvature for Compact Surfaces in S^n
For minimal surfaces in spheres, there is a well known conjecture about the quantization of intrinsic curvature which has been solved only in special cases so far. We recall an intrinsic and an extrinsic version for the known results and extend them to compact non-minimal surfaces in spheres. In particular we discuss special classes like Willmore surfaces and surfaces with parallel mean curvature vector
On the Design of Peer Punishment Experiments
We discuss how technologies of peer punishment might bias the results that are observed in experiments. A crucial parameter is the “fine-to-fee” ratio, which describes by how much the punished subjects income is reduced relatively to the fee the punishing subject has to pay to inflict punishment. We show that a punishment technology commonly used in experiments embeds a variable fine-to-fee ratio and show that it confounds the empirical findings about why, whom, and how much subjects punish
NIRwave: A wave-turbulence-driven solar wind model constrained by PSP observations
We generate a model description of the solar wind based on an explicit
wave-turbulence-driven heating mechanism, and constrain our model with
observational data. We included an explicit coronal heating source term in the
general 3D magnetohydrodynamic code NIRVANA to simulate the properties of the
solar wind. The adapted heating mechanism is based on the interaction and
subsequent dissipation of counter-propagating Alfv\'en waves in the solar
corona, accounting for a turbulent heating rate Q_p. The solar magnetic field
is assumed to be an axisymmetric dipole with a field strength of 1 G. Our model
results are validated against observational data taken by the Parker Solar
Probe (PSP). Our NIRwave solar wind model reconstructs the bimodal structure of
the solar wind with slow and fast wind speeds of 410 km/s and 650 km/s
respectively. The global mass-loss rate of our solar wind model is 2.6e-14
solar masses per year. Despite implementing simplified conditions to represent
the solar magnetic field, the solar wind parameters characterising our
steady-state solution are in reasonable agreement with previously established
results and empirical constraints. The number density from our wind solution is
in good agreement with the derived empirical constraints, with larger
deviations for the radial velocity and temperature. In a comparison to a
polytropic wind model generated with NIRVANA, we find that our NIRwave model is
in better agreement with the observational constraints that we derive.Comment: 14 pages, 12 figures, accepted for publication in A&
Burden and Needs of Patients with Severe GvHD from the Supportive and Palliative Care Perspective—A Literature Review
Graft-versus-host disease (GvHD) is a frequent, and often life-threatening, complication after an allogeneic, hematopoietic stem cell transplantation (allo-SCT). It can appear in an acute or a chronic form and presents different grades of severity. Particularly, the severe forms of GvHD are often responsible for a change of the curative intent for allo-SCT into a palliative goal of care. For this non-systematic review, we conducted a focused literature search in the MEDLINE database via PubMed to examine whether patients with severe forms of GvHD might have special needs and burdens from a supportive and palliative care perspective. To draw a comprehensive picture of this patient group, we included findings on quality of life (QoL) and physical symptoms and function as well as psychological and spiritual well-being. In most domains, patients with severe forms of GvHD showed greater impairment and a higher symptom burden compared to patients with milder forms of GvHD. However, we could not identify any studies that specifically investigated patients with severe forms of GvHD. Further research in this field is necessary to guarantee the highest standard of care for this very special patient group
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