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Changes in epithelial secretory cells and potentiation of neurogenic inflammation in the trachea of rats with respiratory tract infections.
In rats respiratory tract infections due to Sendai virus and coronavirus usually are transient, but they can have long-lasting consequences when accompanied by Mycoplasma pulmonis infections. Morphological alterations in the tracheal epithelium and a potentiation of the inflammatory response evoked by sensory nerve stimulation ("neurogenic inflammation") are evident nine weeks after the infections begin, but the extent to which these changes are present at earlier times is not known. In the present study we characterized these abnormalities in the epithelium and determined the extent to which they are present 3 and 6 weeks after the infections begin. We also determined the magnitude of the potentiation of neurogenic inflammation at these times, whether the potentiation can be reversed by glucocorticoids, and whether a proliferation of blood vessels contributes to the abnormally large amount of plasma extravasation associated with this potentiation. To this end, we studied Long-Evans rats that acquired these viral and mycoplasmal infections from other rats. We found that the tracheal epithelium of the infected rats had ten times as many Alcian blue-PAS positive mucous cells as did that of pathogen-free rats; but it contained none of the serous cells typical of pathogen-free rats, so the total number of secretory cells was not increased. In addition, the epithelium of the infected rats had three times the number of ciliated cells and had only a third of the number of globule leukocytes. In response to an injection of capsaicin (150 micrograms/kg i.v.), the tracheas of the infected rats developed an abnormally large amount of extravasation of two tracers, Evans blue dye and Monastral blue pigment, and had an abnormally large number of Monastral blue-labeled venules, particularly in regions of mucosa overlying the cartilaginous rings. This abnormally large amount of extravasation was blocked by dexamethasone (1 mg/day i.p. for 5 days). We conclude that M. pulmonis infections, exacerbated at the outset by viral infections, result within three weeks in the transformation of epithelial serous cells into mucous cells, the proliferation of ciliated cells, and the depletion of globule leukocytes. They also cause a proliferation of mediator-sensitive blood vessels in the airway mucosa, which is likely to contribute to the potentiation of neurogenic inflammation that accompanies these infections
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Local Kesten–McKay Law for Random Regular Graphs
We study the adjacency matrices of random -regular graphs with large but
fixed degree . In the bulk of the spectrum down to the optimal spectral scale, we prove that the
Green's functions can be approximated by those of certain infinite tree-like
(few cycles) graphs that depend only on the local structure of the original
graphs. This result implies that the Kesten--McKay law holds for the spectral
density down to the smallest scale and the complete delocalization of bulk
eigenvectors. Our method is based on estimating the Green's function of the
adjacency matrices and a resampling of the boundary edges of large balls in the
graphs
Edge rigidity and universality of random regular graphs of intermediate degree
For random -regular graphs on vertices with , we
develop a expansion of the local eigenvalue distribution about the
Kesten-McKay law up to order . This result is valid up to the edge of
the spectrum. It implies that the eigenvalues of such random regular graphs are
more rigid than those of Erd\H{o}s-R\'enyi graphs of the same average degree.
As a first application, for , we show that all nontrivial
eigenvalues of the adjacency matrix are with very high probability bounded in
absolute value by . As a second application, for
, we prove that the extremal eigenvalues are
concentrated at scale and their fluctuations are governed by
Tracy-Widom statistics. Thus, in the same regime of , of all
-regular graphs have second-largest eigenvalue strictly less than .The work of J.H. is supported by the Institute for Advanced Study. A.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 715539_RandMat) and from the Swiss National Science Foundation through the SwissMAP grant. The work of H.-T.Y. is partially supported by NSF Grants DMS-1606305 and DMS-1855509, and a Simons Investigator award
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Edge rigidity and universality of random regular graphs of intermediate degree
© 2020, Springer Nature Switzerland AG. For random d-regular graphs on N vertices with 1 ≪ d≪ N2 / 3, we develop a d- 1 / 2 expansion of the local eigenvalue distribution about the Kesten–McKay law up to order d- 3. This result is valid up to the edge of the spectrum. It implies that the eigenvalues of such random regular graphs are more rigid than those of Erdős–Rényi graphs of the same average degree. As a first application, for 1 ≪ d≪ N2 / 3, we show that all nontrivial eigenvalues of the adjacency matrix are with very high probability bounded in absolute value by (2+o(1))d-1. As a second application, for N2 / 9≪ d≪ N1 / 3, we prove that the extremal eigenvalues are concentrated at scale N- 2 / 3 and their fluctuations are governed by Tracy–Widom statistics. Thus, in the same regime of d, 52 % of all d-regular graphs have second-largest eigenvalue strictly less than 2d-1.The work of J.H. is supported by the Institute for Advanced Study. A.K. gratefully acknowledges funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 715539_RandMat) and from the Swiss National Science Foundation through the SwissMAP grant. The work of H.-T.Y. is partially supported by NSF Grants DMS-1606305 and DMS-1855509, and a Simons Investigator award
The effect of glutamine supplement on small intestinal morphology and xylose absorptive ability of weaned piglets
The purpose of this study is to demonstrate the effects of glutamine (Gln) supplement on small intestinal morphology, xylose absorptive and growth performance of weaned piglets. Forty eight piglets weaned at 28 ± 2 days of age were randomly allotted to three treatment groups. A basal corn-soybean diet was formulated to contain 20.3% protein and 3450 kcal DE/kg diet. Glutamine was supplemented to the basal diet at 0% (control), 1% (Gln 1%) and 2% (Gln 2%). Pigs were fed experimental diets for three weeks. The results showed that the villous height of the Gln groups tended higher than the control group in duodenum and jejunum (P < 0.1). Glutamine supplementation increased plasma net xylose absorptive concentration from 0.78 to 1.20 and 0.95 to 1.23 in Gln 1% and Gln 2% group, respectively, which were better than the control group (0.86 to 0.97) in day 7 to 14 after weaning. Growth performance was not significantly affected by Gln supplement; however, average daily gain was approximately improved from 21 to 28% by Gln supplement compared to the control group during 21 days of experimental period. In summary, the results suggested that dietary supplementation of Gln could be beneficial in small intestinal villous morphology and xylose absorptive capacity, and could have a slight contribution to the average daily gain of weaned piglets.Key words: Glutamine, growth performance, intestinal morphology, weaned piglets
虚拟参考站技术中对流层误差建模方法研究
Author name used in this publication: 黄丁发Author name used in this publication: 丁晓利, DING Xiao-liAuthor name used in this publication: 殷海涛Title in Traditional Chinese: 虛擬參考站技術中對流層誤差建模方法研究Journal title in Traditional Chinese: 測繪學報2006-2007 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe
Bulk eigenvalue statistics for random regular graphs
We consider the uniform random -regular graph on vertices, with for arbitrary . We prove that in the
bulk of the spectrum the local eigenvalue correlation functions and the
distribution of the gaps between consecutive eigenvalues coincide with those of
the Gaussian Orthogonal Ensemble.AK was partly supported by Swiss National Science Foundation grant 144662. HTY was partly supported by NSF grant DMS-1307444 and a Simons Investigator fellowship.his is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the Institute of Mathematical Statistics
Aerobic co-composting degradation of highly PCDD/F-contaminated field soil. A study of bacterial community
© 2018 Elsevier B.V. This study investigated bacterial communities during aerobic food waste co-composting degradation of highly PCDD/F-contaminated field soil. The total initial toxic equivalent quantity (TEQ) of the soil was 16,004 ng-TEQ kg −1 dry weight. After 42-day composting and bioactivity-enhanced monitored natural attenuation (MNA), the final compost product's TEQ reduced to 1916 ng-TEQ kg −1 dry weight (approximately 75% degradation) with a degradation rate of 136.33 ng-TEQ kg −1 day −1 . Variations in bacterial communities and PCDD/F degraders were identified by next-generation sequencing (NGS). Thermophilic conditions of the co-composting process resulted in fewer observed bacteria and PCDD/F concentrations. Numerous organic compound degraders were identified by NGS, supporting the conclusion that PCDD/Fs were degraded during food waste co-composting. Bacterial communities of the composting process were defined by four phyla (Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes). At the genus level, Bacillus (Firmicutes) emerged as the most dominant phylotype. Further studies on specific roles of these bacterial strains are needed, especially for the thermophiles which contributed to the high degradation rate of the co-co-composting treatment's first 14 days
The Classical Harmonic Vibrations of the Atomic Centers of Mass with Micro Amplitudes and Low Frequencies Monitored by the Entanglement between the Two Two-level Atoms in a Single mode Cavity
We study the entanglement dynamics of the two two-level atoms coupling with a
single-mode polarized cavity field after incorporating the atomic centers of
mass classical harmonic vibrations with micro amplitudes and low frequencies.
We propose a quantitative vibrant factor to modify the concurrence of the two
atoms states. When the vibrant frequencies are very low, we obtain that: (i)
the factor depends on the relative vibrant displacements and the initial phases
rather than the absolute amplitudes, and reduces the concurrence to three
orders of magnitude; (ii) the concurrence increases with the increase of the
initial phases; (iii) the frequency of the harmonic vibration can be obtained
by measuring the maximal value of the concurrence during a small time. These
results indicate that even the extremely weak classical harmonic vibrations can
be monitored by the entanglement of quantum states.Comment: 10 pages, 3 figure
Transformation Pathways of Silica under High Pressure
Concurrent molecular dynamics simulations and ab initio calculations show
that densification of silica under pressure follows a ubiquitous two-stage
mechanism. First, anions form a close-packed sub-lattice, governed by the
strong repulsion between them. Next, cations redistribute onto the interstices.
In cristobalite silica, the first stage is manifest by the formation of a
metastable phase, which was observed experimentally a decade ago, but never
indexed due to ambiguous diffraction patterns. Our simulations conclusively
reveal its structure and its role in the densification of silica.Comment: 14 pages, 4 figure
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