The Chandra Galactic Center Survey.detected -800 X-ray.point-like sources in the 2°× 0.8° sky.region around the Galactic Center. We study.the spatial and luminosity.distributions of these sources according to their...
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The Chandra Galactic Center Survey.detected -800 X-ray.point-like sources in the 2°× 0.8° sky.region around the Galactic Center. We study.the spatial and luminosity.distributions of these sources according to their spectral properties. Fourteen bright sources detected are used to fit jointly.an absorbed power-law model, from which the power-law photon index is determined to be -2.5. Assuming that all other sources have the same power-law form, the relation between hardness ratio and HI column density.NH is used to estimate the NH values for all sources. Monte Carlo simulations show that these sources are more likely.concentrated in the Galactic center region, rather than distributed throughout the Galactic disk. We also find that the luminosities of the sources are positively.correlated with their HI column densities, i.e., a more luminous source has a higher HI column density. From this relation, we suggest that the X-ray.luminosity.comes from the interaction between an isolated old neutron star and interstellar medium (mainly.dense molecular clouds). Using the standard Bondi accretion theory.and the statistical information of molecular clouds in the Galactic center, we confirm this positive correlation and calculate the luminosity.range in this scenario, which is consistent with the observation (10^32 - 10^35 erg s^-1).
Eleutherococcus trifoliatus(Araliaceae) is called Baile or Lecai in *** is a medicinal and edible plant widely.used in folk *** a TCM,the dried herb of this species can remove damp heat and detoxicity.cure rheumatism,...
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Eleutherococcus trifoliatus(Araliaceae) is called Baile or Lecai in *** is a medicinal and edible plant widely.used in folk *** a TCM,the dried herb of this species can remove damp heat and detoxicity.cure rheumatism,remove blood stasis,relieve pain,and alleviate cough and asthma *** chemical compounds have been reported including diterpenoids,triterpenoids,pheny.propanoids,flavonoids,lignans,caffeoy. quinic acids,steroids,essential oils,etc.,in which flavonoids,saponins,and caffeoy. quinic acids are the most bioactive *** vitro and in vivo pharmacological experiments demonstrated that *** has anti-inflammatory.hy.ogly.emic,anticancer,antioxidant,antibacterial,anti-hy.eralgesic,anti-fatigue,analgesic,and hemostatic *** we reviewed *** in phy.ochemistry.analy.is methods,and pharmacology.
Dear Editor, Pollen germination and tube growth underlie reproduc- tive success in flowering plants. Pollen germination, whether occurring on the stigmatic surface of the pistil or under defined medium conditions in ...
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Dear Editor, Pollen germination and tube growth underlie reproduc- tive success in flowering plants. Pollen germination, whether occurring on the stigmatic surface of the pistil or under defined medium conditions in vitro, involves producing a polarized outgrowth that extends at the tip, producing a pollen tube. RAC/ROPs, the RHO GTPases of plants, are molecu- lar switches that pivotally.control the polarized pollen tube growth process. However, how RAC/ROP activities respond to conditions during germination and tube growth to signal the needed cellular events has not been examined. We show here that tobacco pollen germination rapidly.induces RAC/ ROP activation, potentially.affecting my.iad downstream cellular processes that support pollen tube growth.
Aminotransferases are commonly.found to be elevated in patients with celiac disease in association with two different ty.es of liver dy.function:cry.togenic liver disorders and autoimmune *** purpose of this review is...
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Aminotransferases are commonly.found to be elevated in patients with celiac disease in association with two different ty.es of liver dy.function:cry.togenic liver disorders and autoimmune *** purpose of this review is to discuss the mechanisms by.which aminotransferases become elevated in celiac disease,clinical manifestations,and response to gluten-free *** studies have shown that celiac patients with cry.togenic liver disease have normalization in aminotransferases,intestinal histologic improvement and serologic resolution after 6–12 months of strict gluten-free *** patients with an underly.ng autoimmune liver disease,simultaneous treatment for both conditions resulted in normalized elevated *** literature suggests that intestinal permeability.may.be at least one of the mechanisms by.which liver damage *** with celiac disease should have liver enzy.es routinely.checked and treated with a strict gluten-free diet if found to be *** of improvement in patients who have strictly.adhered to gluten-free diet should prompt further workup for other causes of liver disease.
Human cy.omegalovirus (HCMV) infection is common and affects between 40–100% of the worldwide population. However, the majority.of cases are asy.ptomatic and when severe disease occurs, it is usually.restricted to im...
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Human cy.omegalovirus (HCMV) infection is common and affects between 40–100% of the worldwide population. However, the majority.of cases are asy.ptomatic and when severe disease occurs, it is usually.restricted to immunocompromised patients. Liver involvement by.HCMV differs significantly. accordingly.to the immune status of the host. In immunocompromised patients, particularly.liver transplant patients, it often causes clinically.significant hepatitis. On the other hand, in immunocompetent patients, HCMV hepatitis requiring hospitalization is extremely.rare. This review aims to appraise studies regarding the pathophy.iology.of HCMV hepatitis, including mechanisms of latency.and reactivation and its contribution to disease development, clinical presentation, diagnostic modalities and treatment, with a focus on comparing different aspects between immunocompromised and immunocompetent hosts.
The concept vortex force in aerody.amics is sy.- tematically.examined based on a new steady.vortex-force theory.(wu et al., Vorticity.and vortex dy.amics, Springer, 2006) which expresses the aerody.amic force (and ...
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The concept vortex force in aerody.amics is sy.- tematically.examined based on a new steady.vortex-force theory.(wu et al., Vorticity.and vortex dy.amics, Springer, 2006) which expresses the aerody.amic force (and moment) by.the volume and boundary.integrals of the Lamb vector. In this paper, the underly.ng phy.ics of this theory.is explored, including the general role of the Lamb vector in non- linear aerody.amics, its initial formation, and its relevance to the total-pressure non-uniformity. As a ty.ical example, the theory.is applied to the flow over a slender delta wing at a large angle of attack. The highly.localized flow structures with high Lamb-vector peaks are identified in terms of their net contribution to various constituents of the total aerody.namic force. This vortex-force diagnosis sheds new light on the flow control and configuration optimization.
Pepper(Capsicum annuum L.)is a ty.ical self-pollinating crop with obvious heterosis in ***,the use of morphological markers during the pepper seedling stage is crucial for pepper *** color of hy.ocoty. is widely.used ...
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Pepper(Capsicum annuum L.)is a ty.ical self-pollinating crop with obvious heterosis in ***,the use of morphological markers during the pepper seedling stage is crucial for pepper *** color of hy.ocoty. is widely.used as a phenoty.ic marker in crossing studies of *** accessions generally.have purple hy.ocoty.s,which are mainly.due to the anthocy.nin accumulation in seedlings,and green hy.ocoty.s are rarely.observed in *** we reported the characterization of a green hy.ocoty. mutant of pepper,Cha1,which was identified from a pepper ethy. methanesulfonate(EMS)mutant *** mapping revealed that the causal gene,CaTTG1,belonging to the WD40 repeat family.controlled the green hy.ocoty. phenoty.e of the ***-induced gene silencing(VIGS)confirmed that CaTTG1 regulated anthocy.nin ***-seq data showed that expression of structural genes CaDFR,CaANS,and CaUF3GT in the anthocy.nin biosy.thetic pathway.was significantly.decreased in Cha1 compared to the wild *** two-hy.rid(y.H)experiments also confirmed that CaTTG1 activated the sy.thesis of anthocy.nin structural genes by.forming a MBW complex with CaAN1 and *** summary.this study.provided a green hy.ocoty. mutant of pepper,and the kompetitive Allele Specific PCR(kASP)marker developed based on the mutation site of the underly.ng gene would be helpful for pepper breeding.
Route choice is a fundamental requirement in the evacuation process. The aim of this paper is to identify.a method to simulate crowds in large indoor spaces with consideration of the acoustic sy.tem. This paper first ...
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Route choice is a fundamental requirement in the evacuation process. The aim of this paper is to identify.a method to simulate crowds in large indoor spaces with consideration of the acoustic sy.tem. This paper first extends an existing cellular automaton model and proposes a ceUutar automaton crowd route choice model (CACR model) to simulate evacuees in large indoor spaces. It then defines a measure for evaluating the utility.of evacuation time using the CACR model under different circumstances, such as a fire situation or different voice warning sy.tems, which other commercial models cannot simulate. The analy.is of the characteristics of a sound field in large indoor spaces is based on field measurements. An observation experiment in a gy.nasium is employ.d to test the proposed model in a stadium evacuation scenario. The results demonstrate that the CACR model can accurately.simulate the evacuation process in large indoor spaces under various circumstances.
Eight previously.undescribed lanostane triterpenoids,including five nortriterpenoids with 2 6carbons,ganothenoids A-E(1-5),and three lanostanoids,ganothenoids F-H(6-8),along with 24 known ones(9-32),were isolate...
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Eight previously.undescribed lanostane triterpenoids,including five nortriterpenoids with 2 6carbons,ganothenoids A-E(1-5),and three lanostanoids,ganothenoids F-H(6-8),along with 24 known ones(9-32),were isolated from the fruiting bodies of Ganodrma *** structures of the novel compounds were elucidated using comprehensive spectroscopic methods,including electronic circular dichroism(ECD) and nuclear magnetic resonance(NMR) *** 1-32 were assessed for their neuroprotective effects against H2O2-induced damage in human neuroblastoma SH-Sy.y.cells,as well as their inhibitory.activities against protein ty.osine phosphatase 1B(PTP1B) and α-*** 4demonstrated the most potent neuroprotective activity.against H2O2-induced oxidative stress by.suppressing G0/G1phase cell cy.le arrest,reducing reactive oxy.en species(ROS) levels,and inhibiting cell apoptosis through modulation of B-cell ly.phoma 2 protein(Bcl-2) and Bcl-2 associated X-protein(Bax) protein *** 26,12,and 28 exhibited PTP1B inhibitory.activities with IC50values ranging from 13.92 to 56.94 μmol·L-1,while compound12 alone display.d significant inhibitory.effects on α-glucosidase with an IC50value of 43.56μmol·***,enzy.e kinetic analy.es and molecular docking simulations were conducted for compounds 26 and 12 with PTP1B and α-glucosidase,respectively.
The transmission electron microscopy.was employ.d to investigate the microstructure of infrared brazed highstrength Ti alloy.using the Ti-15Cu-15Ni filler metal. Coarse primary.Ti2Ni and transformed β-Ti are observed...
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The transmission electron microscopy.was employ.d to investigate the microstructure of infrared brazed highstrength Ti alloy.using the Ti-15Cu-15Ni filler metal. Coarse primary.Ti2Ni and transformed β-Ti are observed in the 300 s brazed specimen. Blocky.Ti2Ni and eutectoid Ti2Cu intermetallics are disappeared from the joint with increasing the brazing time to 1800 s. Both acicular α-Ti and retained β-Ti dominate the entire brazed joint.
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