27 research outputs found
Wallenstein’s Power Problem and Its Consequences
This paper wants to be both: an introduction to game-theoretical thinking as well as a game-theoretical discussion of Schiller’s Wallenstein. Note that the intention of this article is to convince theatergoers and people who work in the theatrical arts that it is worthwhile to study some game theory. Others will hopefully profit from the unusual Wallenstein interpretation. It is not this article’s purpose to teach game theorists, but rather to inspire applications. The drama is depicted as a game and consequently submitted to a formal analysis that is based on the economic concept of rationality. Weber’s definition of power is operationalized and applied to Wallenstein’s decision situation.Power, bargaining, mixed-strategy Nash equilibrium, theater, Wallenstein
The James Webb Space Telescope Mission
Twenty-six years ago a small committee report, building on earlier studies,
expounded a compelling and poetic vision for the future of astronomy, calling
for an infrared-optimized space telescope with an aperture of at least .
With the support of their governments in the US, Europe, and Canada, 20,000
people realized that vision as the James Webb Space Telescope. A
generation of astronomers will celebrate their accomplishments for the life of
the mission, potentially as long as 20 years, and beyond. This report and the
scientific discoveries that follow are extended thank-you notes to the 20,000
team members. The telescope is working perfectly, with much better image
quality than expected. In this and accompanying papers, we give a brief
history, describe the observatory, outline its objectives and current observing
program, and discuss the inventions and people who made it possible. We cite
detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space
Telescope Overview, 29 pages, 4 figure
Isolation and characterization of lactococcal bacteriophages from cultured buttermilk plants in the United States
From July 1993 and June 1994, 27 different lactococcal bacteriophages were isolated from 27 US cultured buttermilk plants located in 23 states. Phages
were characterized by DNA homology, electron
microscopy, restriction patterns, genome size, host
range, and serology. Over 80% (22 of 27) of the
phages were classified into the 936 species, and the
remaining phages were divided almost equally between the P335 species (3 of 27) and the c2 species
(2 of 27). The 936 and c2-type phages had the same
basic morphological and genetic characteristics as
other phages from the same species isolated in other
countries. Very closely related 936 phages were isolated from widely separated areas in the US. The
P335 phages had a very narrow host range and
showed noticeable genetic and immunological diversity. None of the phages could propagate on the two
exopolysaccharide-producing Lactococcus Zactis
strains tested. Novel mechanisms for phage
resistance should be tested for efficiency against
members of the lactococcal phage species 936, c2, and
P335. To our knowledge, this study is the first
thorough examination of industrial lactococcal phages
isolated from buttermilk plants
Tryptophan catabolism is associated with acute GVHD after human allogeneic stem cell transplantation and indicates activation of indoleamine 2,3-dioxygenase
Induction of indoleamine 2,3-dioxygenase (IDO), the rate-limiting enzyme in tryptophan degradation along the kynurenine pathway, acts as a potent immunoregulatory loop. To address its role in human allogeneic stem cell transplantation, we measured major tryptophan metabolites, such as quinolinic acid and kynurenine, in serial urine specimens from 51 patients by liquid chromatography-tandem mass spectrometry. Samples were collected between admission and day 90 after transplantation, and metabolite levels were correlated with early clinical events and outcome. In selected patients, IDO gene expression was assessed by quantitative RT-PCR in intestinal biopsies. Surviving patients had significantly lower metabolite levels on days 28, 42, and 90, respectively, compared with patients dying of GVHD and associated complications (n = 10). Kynurenine levels were directly correlated with severity and clinical course of GVHD: Mean urinary quinolinic acid levels were 4.5 ± 0.3 μmol/mmol creatinine in the absence of acute GVHD, 8.0 ± 1.1 μmol/mmol creatinine for GVHD grade 1 or 2, and 13.5 ± 2.7 μmol/mmol creatinine for GVHD grade 3 or 4 (P < .001), respectively. GVHD-dependent induction of IDO was further suggested by increased expression of IDO mRNA in intestinal biopsies from patients with severe GVHD. Our data indicate reactive release of kynurenines in GVHD-associated inflammation
Phenotypic and genetic characterization of the bacteriophage abortive infection mechanism abiK from Lactococcus lactis
The natural plasmid pSRQ800 isolated from Lactococcus lactis subsp. lactis W1 conferred strong phage
resistance against small isometric phages of the 936 and P335 species when introduced into phage-sensitive L.
lactis strains. It had very limited effect on prolate phages of the c2 species. The phage resistance mechanism
encoded on pSRQ800 is a temperature-sensitive abortive infection system (Abi). Plasmid pSRQ800 was
mapped, and the Abi genetic determinant was localized on a 4.5-kb EcoRI fragment. Cloning and sequencing
of the 4.5-kb fragment allowed the identification of two large open reading frames. Deletion mutants showed
that only orf1 was needed to produce the Abi phenotype. orf1 (renamed abiK) coded for a predicted protein of
599 amino acids (AbiK) with an estimated molecular size of 71.4 kDa and a pI of 7.98. DNA and protein
sequence alignment programs found no significant homology with databases. However, a database query based
on amino acid composition suggested that AbiK might be in the same protein family as AbiA. No phage DNA
replication nor phage structural protein production was detected in infected AbiK1 L. lactis cells. This system
is believed to act at or prior to phage DNA replication. When cloned into a high-copy vector, AbiK efficiency
increased 100-fold. AbiK provides another powerful tool that can be useful in controlling phages during
lactococcal fermentations
Metagenomic analysis of the stool microbiome in patients receiving allogeneic SCT: Loss of diversity is associated with use of systemic antibiotics and more pronounced in gastrointestinal GvHD
Next-generation sequencing of the hypervariable V3 region of the 16s rRNA gene isolated from serial stool specimens collected from 31 patients receiving allogeneic stem cell transplantation (SCT) was performed to elucidate variations in the composition of the intestinal microbiome in the course of allogeneic SCT. Metagenomic analysis was complemented by strain-specific enterococcal PCR and indirect assessment of bacterial load by liquid chromatography-tandem mass spectrometry of urinary indoxyl sulfate. At the time of admission, patients showed a predominance of commensal bacteria. After transplantation, a relative shift toward enterococci was observed, which was more pronounced under antibiotic prophylaxis and treatment of neutropenic infections. The shift was particularly prominent in patients that developed subsequently or suffered from active gastrointestinal (GI) graft-versus-host disease (GVHD). The mean proportion of enterococci in post-transplant stool specimens was 21% in patients who did not develop GI GVHD as compared with 46% in those that subsequently developed GI GVHD and 74% at the time of active GVHD. Enterococcal PCR confirmed predominance of Enterococcus faecium or both E. faecium and Enterococcus faecalis in these specimens. As a consequence of the loss of bacterial diversity, mean urinary indoxyl sulfate levels dropped from 42.5 ± 11 μmol/L to 11.8 ± 2.8 μmol/L in all post-transplant samples and to 3.5 ± 3 μmol/L in samples from patients with active GVHD. Our study reveals major microbiome shifts in the course of allogeneic SCT that occur in the period of antibiotic treatment but are more prominent in association with GI GVHD. Our data indicate early microbiome shifts and a loss of diversity of the intestinal microbiome that may affect intestinal inflammation in the setting of allogeneic SCT
Hind limb kinematics during therapeutic exercises in dogs with osteoarthritis of the hip joints
Toward Biomarkers for Chronic Graft-versus-Host Disease: National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease: III. Biomarker Working Group Report
AbstractBiology-based markers that can be used to confirm the diagnosis of chronic graft-versus-host disease (GVHD) or monitor progression of the disease could help in the evaluation of new therapies. Biomarkers have been defined as any characteristic that is objectively measured and evaluated as an indicator of a normal biologic or pathogenic process, a pharmacologic response to a therapeutic intervention, or a surrogate end point intended to substitute for a clinical end point. The following applications of biomarkers could be useful in chronic GVHD clinical trials or management: (1) predicting response to therapy; (2) measuring disease activity and distinguishing irreversible damage from continued disease activity; (3) predicting the risk of developing chronic GVHD; (4) diagnosing chronic GVHD: (5) predicting the prognosis of chronic GVHD; (6) evaluating the balance between GVHD and graft-versus-leukemia effects (graft-versus-leukemia or GVT); and (7) serving as a surrogate end point for therapeutic response. Such biomarkers can be identified by either hypothesis-driven testing or by high-throughput discovery-based methods. To date, no validated biomarkers have been established for chronic GVHD, although several candidate biomarkers have been identified from limited hypothesis-driven studies. Both approaches have merit and should be pursued. The consistent treatment and standardized documentation needed to support biomarker studies are most likely to be satisfied in prospective clinical trials