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The Second Wave of Chinese Outbound Tourism Growth, Segmentation, Sophistication
The accessory bacteriochlorophyll
The primary electron transfer in reaction centers of Rhodobacter sphaeroides is studied by subpicosecond absorption spectroscopy with polarized light in the spectral range of 920-1040 nm. Here the bacteriochlorophyll anion radical has an absorption band while the other pigments of the reaction center have vanishing ground-state absorption. The transient absorption data exhibit a pronounced 0.9-ps kinetic component which shows a strong dichroism. Evaluation of the data yields an angle between the transition moments of the special pair and the species related with the 0.9-ps kinetic component of 26 +/- 8 degrees. This angle compares favorably with the value of 29 degrees expected for the reduced accessory bacteriochlorophyll. Extensive transient absorbance data are fully consistent with a stepwise electron transfer via the accessory bacteriochlorophyll
a meta-analysis
The objective of the conducted meta-analysis was to assess the efficacy of the
treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum
uterine infections have a high prevalence and a very negative effect on
reproductive performance in dairy cattle. Because of a wide discordance
between research results, a meta-analysis of the efficacy of the treatment of
bovine endometritis with PGF(2α) was conducted. A comprehensive literature
search was performed using online databases to reveal a total of 2,307
references. In addition, 5 articles were retrieved by reviewing citations.
After applying specific exclusion criteria and evaluating specific evidence
parameters, 5 publications, comprising 6 trials, were eligible for being
analyzed by means of meta-analysis. Data for each trial were extracted and
analyzed using meta-analysis software Review Manager (version 5.1; The Nordic
Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were
calculated on calving to first service and calving to conception interval.
Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative
effect on both reproductive performance parameters. Heterogeneity was
substantial for calving to first service and calving to conception interval
[I(2) (measure of variation beyond chance)=100 and 87%, respectively];
therefore, random-effects models were used. Sensitivity analysis as well as
subgroup analysis showed that the performance of randomization was influential
in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a
publication bias toward smaller studies that reported a prolonged calving to
conception interval after a PGF(2α) treatment. We conclude that the
investigation of this subject by means of meta-analysis did not reveal an
improvement of reproductive performance of cows with endometritis after
treatment with PGF(2α). Furthermore, there is a shortage of comparable high
quality studies investigating reproductive performance after PGF(2α) treatment
of cows with chronic endometritis
quality and comparability of clinical trials investigating the efficacy of prostaglandin F2α for the treatment of bovine endometritis
The objective of this study was to evaluate the quality and comparability of
published literature, and to summarize the effect of prostaglandin F(2α)
(PGF(2α)) for the treatment of endometritis. It has been postulated that there
is a dearth of high-level evidence-based research results in veterinary
medicine. Also, there is a marked variation in the quality of studies in
veterinary and animal science. Post-partum uterine infections occur commonly
in dairy cattle and are reported to have a negative impact on reproductive
performance. A comprehensive literature search was conducted utilizing online
databases revealing a total of 2723 references. After applying specific
exclusion criteria, a total of 68 trials were eligible for further analysis.
These articles were evaluated utilizing specific parameters listed in an
evaluation form such as randomization and the involvement of control groups.
The analysis revealed that more than half of the trials (51·5%) were at least
20 years old. Furthermore, we found that about one third (36·8%) of all trials
were controlled and randomized, while 3 of those (4·4%) were also blinded. Of
those trials which calculated a calving-to-conception interval (n=30), 50% of
the authors claimed an improvement, which was statistically significant in
23·3% of the cases. We conclude that there is a wide discrepancy between
research results investigating the efficacy of PGF(2α)
A critical evaluation of diagnostic methods used to identify dairy cows with acute post-partum metritis in the current literature
The overall objective of this study was to investigate how relevant research
publications address the validity of diagnostic methods for acute puerperal
metritis (APM) in dairy cows, a disease commonly treated with antibiotic
drugs. Therefore, a literature search was conducted in Journal of Dairy
Science, Theriogenology, Animal Reproduction Science and The Veterinary
Journal utilizing the ScienceDirect database. The search revealed 259 articles
addressing APM. After applying exclusion criteria, a total of 48 trials
remained. It was determined whether the author gave a clear definition of APM,
the time of diagnosis relative to calving, and the person who performed the
diagnosis. Studies were checked for the presence of definitions of possible
findings, thresholds, and test characteristics of the methods used. Overall 9
different diagnostic methods were employed. On average 2·5 ± 1·75 diagnostic
methods were used in a study. References to support the use of the diagnostic
methods were provided in 10 of 48 articles (20·8%). Vaginal discharge,
transrectal palpation and rectal temperature were examined in 39, 22, and 21
of the studies, respectively. Thresholds for diagnostic tests and test
characteristics were mentioned in 6 and 3 of the 48 articles, respectively.
Based on this systematic review of 48 research papers the evidence supporting
the use of the diagnostic methods to identify cows with APM has either been
not reported or is weak. In conclusion, the reporting of the diagnostic
methods to identify cows with APM needs to be improved and further high-
quality research is necessary to improve diagnostic performance of the methods
employed
Spontaneous symmetry breaking in spinor Bose-Einstein condensates
We present an analytical model for the theoretical analysis of spin dynamics
and spontaneous symmetry breaking in a spinor Bose-Einstein condensate (BEC).
This allows for an excellent intuitive understanding of the processes and
provides good quantitative agreement with experimental results in Phys. Rev.
Lett. 105, 135302 (2010). It is shown that the dynamics of a spinor BEC
initially prepared in an unstable Zeeman state mF=0 (|0>) can be understood by
approximating the effective trapping potential for the state |+-1> with a
cylindrical box potential. The resonances in the creation efficiency of these
atom pairs can be traced back to excitation modes of this confinement. The
understanding of these excitation modes allows for a detailed characterization
of the symmetry breaking mechanism, showing how a twofold spontaneous breaking
of spatial and spin symmetry can occur. In addition a detailed account of the
experimental methods for the preparation and analysis of spinor quantum gases
is given.Comment: 12 pages, 14 figure
The promoter of human p22/PACAP response gene 1 (PRG1) contains functional binding sites for the p53 tumor suppressor and for NFÎșB
AbstractWe describe functional binding sites for the tumor suppressor p53 and for NFÎșB residing in the promoter of the novel human early response gene p22/PRG1 (IEX-1/DIF-2). Gel shift and supershift assays demonstrate binding of p53 and NFÎșB to their corresponding sites in vitro. CAT-reporter gene assays show transactivation of the human p22/PRG1 promoter by p53 in Hep3B cells stably transfected with a temperature-sensitive mutant p53, but not in p53-deficient Hep3B cells. TNFα induced NFÎșB dependent transactivation was shown in HepG2 cells or in 818-4 pancreatic cancer cells. These data imply that human p22/PRG1 is a target gene for p53 and NFÎșB involved in growth regulation and stress response
Spatially Resolved Tomographic Assessment of Axial Mixing in Structured and Random Packings
AbstractThe liquid axial dispersion inside modern structured packings (Sulzer Mellapakâą 500.Y, Raschig SuperâPak 350Y) and one random packing of the 4th generation (Raschig SuperâRing 0.3) was measured by means of computed tomography. As the gas velocity is known to have little effect on the liquid axial dispersion at low hydraulic load, all experiments were conducted without countercurrent gas flow at liquid loads of B = 10, 15, and 20âm3mâ2hâ1 in a column with an inner diameter of 100âmm. Injection of the Xârayâactive tracer potassium iodide allows the identification of active and passive liquid accumulations inside the structured packing. Good agreement was found between the active liquid holdup from tomographic images and the total holdup calculated from the mean residence time for the structured packings.Combining Xârayâactive tracers und computed tomography, the liquid holdup and interfacial area inside structured and random packings were analyzed. Different kinds of dispersion effects were detected depending on the packing geometry.
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