57 research outputs found
Protoclusters at z=5.7: A view from the MultiDark galaxies
Protoclusters, which will yield galaxy clusters at lower redshift, can
provide valuable information on the formation of galaxy clusters. However,
identifying progenitors of galaxy clusters in observations is not an easy task,
especially at high redshift. Different priors have been used to estimate the
overdense regions that are thought to mark the locations of protoclusters. In
this paper, we use mimicked Ly-emitting galaxies at to identify
protoclusters in the MultiDark galaxies, which are populated by applying three
different semi-analytic models to the 1 MultiDark Planck2
simulation. To compare with observational results, we extend the criterion 1 (a
Ly luminosity limited sample), to criterion 2 (a match to the observed
mean galaxy number density). To further statistically study the finding
efficiency of this method, we enlarge the identified protocluster sample
(criterion 3) to about 3500 at and study their final mass distribution.
The number of overdense regions and their selection probability depends on the
semi-analytic models and strongly on the three selection criteria (partly by
design). The protoclusters identified with criterion 1 are associated with a
typical final cluster mass of which is in
agreement with the prediction (within ) of an observed massive
protocluster at . Identifying more protoclusters allows us to
investigate the efficiency of this method, which is more suitable for
identifying the most massive clusters: completeness () drops
rapidly with decreasing halo mass. We further find that it is hard to have a
high purity () and completeness simultaneously.Comment: 10 pages, 4 figures, 2 tables, version matched to the publication in
MNRA
New Polyketides With Anti-Inflammatory Activity From the Fungus Aspergillus rugulosa
Two new polyketide compounds, asperulosins A and B (1–2), and one new prenylated small molecule, asperulosin C (3), along with nine known compounds (4–12), were isolated and identified from a fungus Aspergillus rugulosa. Their structures were extensively elucidated via HRESIMS, 1D, and 2D NMR analysis. The absolute configurations of the new compounds were determined by the comparison of their electronic circular dichroism (ECD), calculated ECD spectra, and the detailed discussion with those in previous reports. Structurally, compounds 1 and 2 belonged to the polyketide family and were from different origins. Compound 2 was constructed by five continuous quaternary carbon atoms, which occur rarely in natural products. All of the isolates were evaluated for anti-inflammatory activity against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW264.7 cells. Among those, compounds 1 and 5 showed a significant inhibitory effect on NO production with IC50 values of 1.49 ± 0.31 and 3.41 ± 0.85 μM, respectively. Additionally, compounds 1 and 5 markedly increased the secretion of anti-inflammatory cytokine IL10 while suppressing the secretion of pro-inflammatory cytokines IL6, TNF-α, IFN-γ, MCP-1, and IL12. Besides, 1 and 5 inhibited the transcription level of pro-inflammatory macrophage markers IL6, IL1β, and TNF-α while remarkably elevating the anti-inflammatory factor IL10 and M2 macrophage markers ARG1 and CD206. Moreover, 1 and 5 restrained the expression and nuclear translocation of NF-κB, as well as its downstream signaling proteins COX-2 and iNOS. All these results suggest that 1 and 5 have potential as anti-inflammatory agents, with better or comparable activities than those of the positive control, dexamethasone
Comparison of Relaxation Modulus Converted from Frequency- and Time-Dependent Viscoelastic Functions through Numerical Methods
Due to the difficulty of obtaining relaxation modulus directly from experiments, many interconversion methods from other viscoelastic functions to relaxation modulus were developed in previous years. The objectives of this paper were to analyze the difference of relaxation modulus converted from dynamic modulus and creep compliance and explore its potential causes. The selected methods were the numerical interconversions based on Prony series representation. For the dynamic to relaxation conversion, the time spectrum was determined by the collocation method. Meanwhile, for the creep to relaxation conversion, both the collocation method and least squares method were adopted to perform the Laplace transform. The results show that these two methods do not present a significant difference in estimating relaxation modulus. Their difference mostly exists in the transient reduced time region. Calculating the average of two methods is suggested to avoid great deviation of single experiment. To predict viscoelastic responses from creep compliance, the collocation method yields comparable results to the least squares method. Thus, simply-calculated collocation method may be preferable in practice. Further, the master curve pattern is sensitive to the Prony series coefficients. The difference in transient reduced time region may be attributed to the indeterminate Prony series coefficients
Two new species of Verruconis from Hainan, China
Two new species of the genus Verruconis, V. hainanensis and V. pseudotricladiata, were described using combined morphological and DNA sequence data. The DNA sequences of respective strains including nuclear ribosomal DNA genes (nuSSU, ITS, nuLSU) and fragments of three protein-coding genes (ACT1, BT2, TEF1) were sequenced and compared with those from closely-related species to genera Ochroconis and Verruconis (Family Sympoventuriaceae, Order Venturiales). Morphologically, both species showed typical ampulliform conidiophores and conidiogenous cells, features not seen in other species of Verruconis. The conidia of V. hainanensis are fusiform and those of V. pseudotricladiata are Y or T shaped, similar to old members of a closely-related genus Scolecobasidium. The addition of these two new species provides a new perspective on the heterogeneity of Scolecobasidium
Two new species of Verruconis from Hainan, China
Two new species of the genus Verruconis, V. hainanensis and V. pseudotricladiata, were described using combined morphological and DNA sequence data. The DNA sequences of respective strains including nuclear ribosomal DNA genes (nuSSU, ITS, nuLSU) and fragments of three protein-coding genes (ACT1, BT2, TEF1) were sequenced and compared with those from closely-related species to genera Ochroconis and Verruconis (Family Sympoventuriaceae, Order Venturiales). Morphologically, both species showed typical ampulliform conidiophores and conidiogenous cells, features not seen in other species of Verruconis. The conidia of V. hainanensis are fusiform and those of V. pseudotricladiata are Y or T shaped, similar to old members of a closely-related genus Scolecobasidium. The addition of these two new species provides a new perspective on the heterogeneity of Scolecobasidium
Predictors of extubation failure in neurocritical patients identified by a systematic review and meta-analysis.
BACKGROUND: Prediction of extubation failure, particularly in neurocritical patients, is unique and controversial. We conducted a systematic review and meta-analysis to identify the risk factors for extubation failure in these patients. METHODS: A literature search of databases (MEDLINE, EMBASE, the Cochrane Library, and Web of Science) was performed up to August of 2013 to identify trials that evaluated extubation failure predictors. Included trials were either prospective or retrospective cohort studies. RESULTS: Nine studies involving 928 participants were included. The systematic review and meta-analysis revealed that the following were predictive for extubation failure: pneumonia, atelectasis, mechanical ventilation of >24 h, a low Glasgow Coma Scale score (7-9T) (OR = 4.96, 95% CI = 1.61-15.26, P = 0.005), the inability to follow commands (OR = 2.07, 95% CI = 1.15-3.71, P = 0.02), especially the command to close the eyes, thick secretion, and no intact gag reflex. Meanwhile, the following were not predictive for extubation failure: sex, secretion volume, coughing upon suctioning, and the inability to follow one command among showing two fingers, wiggling the toes, or coughing on command. Additionally, some traditional weaning parameters were shown to poorly predict extubation failure in neurocritical patients. CONCLUSIONS: Besides pneumonia, atelectasis, and the duration of mechanical ventilation, other factors that should be taken into consideration in the prediction of extubation failure when neurocritical patients are weaned from tracheal intubation include neurologic abilities (Glasgow Coma Scale score and following commands), the secretion texture, and the presence of a gag reflex
Effects of probucol on restenosis after percutaneous coronary intervention: a systematic review and meta-analysis.
Restenosis after percutaneous coronary intervention (PCI) is a remained clinical problem which limits long-term success of PCI. Although there was recognition that probucol in treating restenosis after percutaneous transluminal coronary angioplasty, the efficacy of probucol on restenosis after stent-implantation is controversial. So this meta-analysis was conducted to investigate the association between probucol and late restenosis.Articles were assessed by four trained investigators, with divergences resolved by consensus. PubMed, EMBASE, ScienceDirect and the Cochrane Central Register of clinical trials were searched for pertinent studies. Inclusion criteria were random allocated to treatment and a comparison of probucol-treated patients and control patients (not treated with lipid-lowering drug) undergoing PCI.Fifteen studies with 859 subjects were analyzed. Major outcome, binary angiographic restenosis defined as >50% stenosis upon follow-up angiography, was significantly decreased with probucol treatment (RR = 0.59 [0.43, 0.80] among vessels, P = 0.0007; and RR = 0.52 [0.40, 0.68] among patients, P<0.00001). Probucol also increased the minimal luminal diameter (SMD = 0.45 [0.30, 0.61], P<0.00001) and decreased late loss upon follow-up after 6 months (SMD = -0.41 [-0.60, -0.22], P<0.0001). Moreover, there was a significantly lower incidence of major adverse cardiac events (MACE) in the probucol group than control group (RR = 0.69 [0.51, 0.93], P = 0.01).Probucol is more than a lipid-lowering drug. It is also effective in reducing the risk of restenosis and incidence of MACE after PCI
The quality assessment of individual studies included.
<p>The quality assessment of individual studies included.</p
Meta-analysis result of following commands.
<p>Meta-analysis result of following commands.</p
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