2,307 research outputs found
Gene transcription analysis during interaction between potato and Ralstonia solanacearum
Bacterial wilt (BW) caused by Ralstonia solanacearum (Rs) is an important quarantine disease that spreads worldwide and infects hundreds of plant species. The BW defense response of potato is a complicated continuous process, which involves transcription of a battery of genes. The molecular mechanisms of potato-Rs interactions are poorly understood. In this study, we combined suppression subtractive hybridization and macroarray hybridization to identify genes that are differentially expressed during the incompatible interaction between Rs and potato. In total, 302 differentially expressed genes were identified and classified into 12 groups according to their putative biological functions. Of 302 genes, 81 were considered as Rs resistance-related genes based on the homology to genes of known function, and they have putative roles in pathogen recognition, signal transduction, transcription factor functioning, hypersensitive response, systemic acquired resistance, and cell rescue and protection. Additionally, 50 out of 302 genes had no match or low similarity in the NCBI databases, and they may represent novel genes. Of seven interesting genes analyzed via RNA gel blot and semi-quantitative RT-PCR, six were induced, one was suppressed, and all had different transcription patterns. The results demonstrate that the response of potato against Rs is rapid and involves the induction of numerous various genes. The genes identified in this study add to our knowledge of potato resistance to Rs
Geometric Entropy of Nonrelativistic Fermions and Two Dimensional Strings
We consider the geometric entropy of free nonrelativistic fermions in two
dimensions and show that it is ultraviolet finite for finite fermi energies,
but divergent in the infrared. In terms of the corresponding collective field
theory this is a {\em nonperturbative} effect and is related to the soft
behaviour of the usual thermodynamic entropy at high temperatures. We then show
that thermodynamic entropy of the singlet sector of the one dimensional matrix
model at high temperatures is governed by nonperturbative effects of the
underlying string theory. In the high temperature limit the ``exact''
expression for the entropy is regular but leads to a negative specific heat,
thus implying an instability. We speculate that in a properly defined two
dimensional string theory, the thermodynamic entropy could approach a constant
at high temperatures and lead to a geometric entropy which is finite in the
ultraviolet.Comment: LaTex, 19 pages, no figures. Some references adde
The Consistent Result of Cosmological Constant From Quantum Cosmology and Inflation with Born-Infeld Scalar Field
The Quantum cosmology with Born-Infeld(B-I) type scalar field is considered.
In the extreme limits of small cosmological scale factor the wave function of
the universe can also be obtained by applying the methods developed by
Hartle-Hawking(H-H) and Vilenkin. H-H wave function predicts that most Probable
cosmological constant equals to (
equals to the maximum of the kinetic energy of scalar field). It is different
from the original results() in cosmological constant obtained by
Hartle-Hawking. The Vilenkin wave function predicts a nucleating unverse with
largest possible cosmological constant and it is larger than . The
conclusions have been nicely to reconcile with cosmic inflation. We investigate
the inflation model with B-I type scalar field, and find that depends on
the amplitude of tensor perturbation , with the form
The vacuum energy in inflation epoch depends on the
tensor-to-scalar ratio . The amplitude of the
tensor perturbation can, in principle, be large enough to be
discovered. However, it is only on the border of detectability in future
experiments. If it has been observed in future, this is very interesting to
determine the vacuum energy in inflation epoch.Comment: 12 pages, one figure, references added, accepted by European Physical
Journal
Relationships between intrauterine fetal growth trajectories and markers of adiposity and inflammation in young adults
Background
There is now good evidence that events during gestation significantly influence the developmental well-being of an individual in later life. This study aimed to investigate the relationships between intrauterine growth trajectories determined by serial ultrasound and subsequent markers of adiposity and inflammation in the 27-year-old adult offspring from the Raine Study, an Australian longitudinal pregnancy cohort.
Methods
Ultrasound fetal biometric measurements including abdominal circumference (AC), femur length (FL), and head circumference (HC) from 1333 mother-fetal pairs (Gen1–Gen2) in the Raine Study were used to develop fetal growth trajectories using group-based trajectory modeling. Linear mixed modeling investigated the relationship between adult body mass index (BMI), waist circumference (WC), and high-sensitivity C-reactive protein (hs-CRP) of Gen2 at 20 (n = 485), 22 (n = 421) and 27 (n = 437) years and the fetal growth trajectory groups, adjusting for age, sex, adult lifestyle factors, and maternal factors during pregnancy.
Results
Seven AC, five FL and five HC growth trajectory groups were identified. Compared to the average-stable (reference) group, a lower adult BMI was observed in two falling AC trajectories: (β = −1.45 kg/m2, 95% CI: −2.43 to −0.46, P = 0.004) and (β = −1.01 kg/m2, 95% CI: −1.96 to −0.05, P = 0.038). Conversely, higher adult BMI (2.58 kg/m2, 95% CI: 0.98 to 4.18, P = 0.002) and hs-CRP (37%, 95% CI: 9–73%, P = 0.008) were observed in a rising FL trajectory compared to the reference group. A high-stable HC trajectory associated with 20% lower adult hs-CRP (95% CI: 5–33%, P = 0.011).
Conclusion
This study highlights the importance of understanding causes of the unique patterns of intrauterine growth. Different fetal growth trajectories from early pregnancy associate with subsequent adult adiposity and inflammation, which predispose to the risk of diabetes and cardiometabolic disease
HuR binding to AU-rich elements present in the 3 ' untranslated region of Classical swine fever virus
Background: Classical swine fever virus (CSFV) is the member of the genus Pestivirus under the family Flaviviridae. The 5' untranslated region (UTR) of CSFV contains the IRES, which is a highly structured element that recruits the translation machinery. The 3' UTR is usually the recognition site of the viral replicase to initiate minus-strand RNA synthesis. Adenosine-uridine rich elements (ARE) are instability determinants present in the 3' UTR of short-lived mRNAs. However, the presence of AREs in the 3' UTR of CSFV conserved in all known strains has never been reported. This study inspects a possible role of the ARE in the 3' UTR of CSFV. Results: Using RNA pull-down and LC/MS/MS assays, this study identified at least 32 possible host factors derived from the cytoplasmic extracts of PK-15 cells that bind to the CSFV 3' UTR, one of which is HuR. HuR is known to bind the AREs and protect the mRNA from degradation. Using recombinant GST-HuR, this study demonstrates that HuR binds to the ARE present in the 3' UTR of CSFV in vitro and that the binding ability is conserved in strains irrespective of virulence. Conclusions: This study identified one of the CSFV 3' UTR binding proteins HuR is specifically binding to in the ARE region
Characterization of latex allergenic components by capillary zone electrophoresis and N-terminal sequence analysis
In a previous study, protein components purified from latex gloves that elicited allergenic reactions were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and yielded apparent molecular weights of 14, 22, 30, 34, 46, and 58 kD, These allergenic components were isolated for further characterization by capillary zone electrophoresis and N-terminal amino acid sequence analysis. These components all migrated at approximately 25 and 35 min on capillary zone electrophoresis, Diode array spectral analysis detected indistinguishable characteristics between these two protein peaks, In addition, complex formation of these components with patients' immunoglobulin was demonstrated by capillary zone electrophoresis. Analysis of components separated by SDS-PAGE on a polyvinylidene difluoride membrane showed that the first 13 residues were identical to the sequence of hevein, Based on the criteria of charge-to-mass ratio and N-terminal amino acid sequence, our results suggest that these components of latex proteins are similar in the primary structure
Testing Holographic Principle from Logarithmic and Higher Order Corrections to Black Hole Entropy
The holographic principle is tested by examining the logarithmic and higher
order corrections to the Bekenstein-Hawking entropy of black holes. For the BTZ
black hole, I find some disagreement in the principle for a holography screen
at spatial infinity beyond the leading order, but a holography with the screen
at the horizon does not, with an appropriate choice of a period parameter,
which has been undetermined at the leading order, in Carlip's horizon-CFT
approach for black hole entropy in any dimension. Its higher dimensional
generalization is considered to see a universality of the parameter choice. The
horizon holography from Carlip's is compared with several other realizations of
a horizon holography, including induced Wess-Zumino-Witten model approaches and
quantum geometry approach, but none of the these agrees with Carlip's, after
clarifications of some confusions. Some challenging open questions are listed
finally.Comment: To appear in JHEP. The corrections in Sec.2 with those that follow
are more clearly explained. Careful distingtion between the implications of
my results to AdS/CFT and to the holograhic principl
Running Spectral Index and Formation of Primordial Black Hole in Single Field Inflation Models
A broad range of single field models of inflation are analyzed in light of
all relevant recent cosmological data, checking whether they can lead to the
formation of long-lived Primordial Black Holes (PBHs). To that end we calculate
the spectral index of the power spectrum of primordial perturbations as well as
its first and second derivatives. PBH formation is possible only if the
spectral index increases significantly at small scales, i.e. large wave number
. Since current data indicate that the first derivative of the
spectral index is negative at the pivot scale , PBH formation
is only possible in the presence of a sizable and positive second derivative
("running of the running") . Among the three small-field and five
large-field models we analyze, only one small-field model, the "running mass"
model, allows PBH formation, for a narrow range of parameters. We also note
that none of the models we analyze can accord for a large and negative value of
, which is weakly preferred by current data.Comment: 26 pages, 5 figures, Refs. added, Minor textual change; version to
appear in JCA
Near-threshold Production in Heavy-ion Collisions
Within a hadronic transport model we study in detail contributions to kaon
yields and momentum spectra from various baryon (resonance)-baryon (resonance)
and interactions in heavy-ion collisions at beam energies near the
free-space kaon production threshold. It is found that the finite lifetime of
baryon resonances affects significantly the shape of kaon spectra, and the high
energy parts of the kaon spectra are dominated by kaons from processes. resonances are found to contribute
about 10\% to the kaon yield. Effects of boosting the Fermi momentum
distributions of the two colliding nuclei into their center of mass frame,
centrality of the reaction as well as the nuclear equation of state on kaon
yields and spectra are also discussed. Model calculations on ,
and spectra for the reaction of Au+Au at GeV are
compared with the experimental data from the KaoS collaboration.Comment: 18 pages, 11 figures available upon request. TAMU preprint #940403
Scalar-Tensor Theory of Gravity and Generalized Second Law of Thermodynamics on the Event Horizon
In blackhole physics, the second law of thermodynamics is generally valid
whether the blackhole is a static or a non-static one. Considering the universe
as a thermodynamical system the second law of blackhole dynamics extends to the
non-negativity of the sum of the entropy of the matter and the horizon, known
as generalized second law of thermodynamics(GSLT). Here, we have assumed the
universe to be bounded by the event-horizon or filled with perfect fluid and
holographic dark energy in two cases. Thus considering entropy to be an
arbitrary function of the area of the event-horizon, we have tried to find the
conditions and the restrictions over the scalar field and equation of state for
the validity of the GSLT and both in quintessence-era and in phantom-era in
scalar tensor theory.Comment: 8 page
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