112 research outputs found
Sodium Diffusion through Aluminum-Doped Zeolite BEA System: Effect of Water Solvation
To investigate the effect of hydration on the diffusion of sodium ions through the aluminum-doped zeolite BEA system (Si/Al = 30), we used the grand canonical Monte Carlo (GCMC) method to predict the water absorption into aluminosilicate zeolite structure under various conditions of vapor pressure and temperature, followed by molecular dynamics (MD) simulations to investigate how the sodium diffusion depends on the concentration of water molecules. The predicted absorption isotherm shows first-order-like transition, which is commonly observed in hydrophobic porous systems. The MD trajectories indicate that the sodium ions diffuse through zeolite porous structures via hopping mechanism, as previously discussed for similar solid electrolyte systems. These results show that above 15 wt % hydration (good solvation regime) the formation of the solvation cage dramatically increases sodium diffusion by reducing the hopping energy barrier by 25% from the value of 3.8 kcal/mol observed in the poor solvation regime
Hybrid Renormalization for Quasi Distribution Amplitudes of A Light Baryon
We develop a hybrid scheme to renormalize quasi distribution amplitudes of a
light baryon on the lattice, which combines the self-renormalization and ratio
scheme. By employing self-renormalization, the UV divergences and linear
divergence at large spatial separations in quasi distribution amplitudes are
removed without introducing extra nonperturbative effects, while making a ratio
with respect to the zero-momentum matrix element can properly remove the UV
divergences in small spatial separations. As a specific application,
distribution amplitudes of the baryon made of are investigated,
and the requisite equal-time correlators, which define quasi distribution
amplitudes in coordinate space, are perturbatively calculated up to the
next-to-leading order in strong coupling constant . These
perturbative equal-time correlators are used to convert lattice QCD matrix
elements to the continuum space during the renormalization process.
Subsequently, quasi distribution amplitudes are matched onto lightcone
distribution amplitudes by integrating out hard modes and the corresponding
hard kernels are derived up to next-to-leading order in including
the hybrid counterterms. These results are valuable in the lattice-based
investigation of the lightcone distribution amplitudes of a light baryon from
the first principles of QCD.Comment: 25 pages, 4 figure
Codon optimization, expression, purification, and functional characterization of recombinant human IL-25 in Pichia pastoris
Interleukin (IL)-25 (also known as IL-17E) is a distinct member of the IL-17 cytokine family which induces IL-4, IL-5, and IL-13 expression and promotes pathogenic T helper (Th)-2 cell responses in various organs. IL-25 has been shown to have crucial role between innate and adaptive immunity and also a key component of the protection of gastrointestinal helminthes. In this study, to produce bioactive recombinant human IL-25 (rhIL-25), the cDNA of mature IL-25 was performed codon optimization based on methylotropic yeast Pichia pastoris codon bias and cloned into the expression vector pPICZαA. The recombinant vector was transformed into P. pichia strain X-33 and selected by zeocin resistance. Benchtop fermentation and simple purification strategy were established to purify the rhIL-25 with about 17 kDa molecular mass. Functional analysis showed that purified rhIL-25 specifically bond to receptor IL-17BR and induce G-CSF production in vitro. Further annexin V-FITC/PI staining assay indicated that rhIL-25 induced apoptosis in two breast cancer cells, MDA-MB-231 and HBL-100. This study provides a new strategy for the large-scale production of bioactive IL-25 for biological and therapeutic applications
Heat Transfer and Failure Mode Analyses of Ultrahigh-Temperature Ceramic Thermal Protection System of Hypersonic Vehicles
The transient temperature distribution of the ultrahigh-temperature ceramic (UHTC) thermal protection system (TPS) of hypersonic vehicles is calculated using finite volume method. Convective cooling enables a balance of heat increment and loss to be achieved. The temperature in the UHTC plate at the balance is approximately proportional to the surface heat flux and is approximately inversely proportional to the convective heat transfer coefficient. The failure modes of the UHTCs are presented by investigating the thermal stress field of the UHTC TPS under different thermal environments. The UHTCs which act as the thermal protection materials of hypersonic vehicles can fail because of the tensile stress at the lower surface, an area above the middle plane, and the upper surface as well as because of the compressive stress at the upper surface. However, the area between the lower surface and the middle plane and a small area near the upper surface are relatively safe. Neither the compressive stress nor the tensile stress will cause failure of these areas
The metabolic repression effect of carbon-ion radiotherapy in synchronous hormone-sensitive oligometastatic prostate cancer
BackgroundMetastatic prostate cancer (PCa) poses a significant public health concern. While radiation therapy (RT) is commonly utilized in the treatment of synchronous oligometastatic hormone sensitive prostate cancer (OM-HSPC), the occurrence of biochemical recurrence still remains. To deepen our understanding and optimize the outcome of OM-HSPC, we conducted this study to investigate the characteristics of PCa progression and explore potential synergistic mechanisms involving carbon-ion radiotherapy (CIRT) and neoadjuvant androgen deprivation treatment (naADT) in OM-HSPC.MethodsMetabolomic analysis was conducted with 72 urinary samples (at different timepoints) from 33 Patients (T2-3N0M0-1b) and 18 healthy volunteers by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). MetaboAnalyst website and R software were employed for metabolomic analysis and visualization (using the criteria of p value < 0.05 and |FC|>1.5). The impact of CIRT on metabolism were further verified and explored through in vitro and in vivo experiments.ResultsWe found that most metabolites (223 out of 233) were upregulated in treatment-naïve PCa samples compared to healthy samples. After naADT, 60 core risk metabolites were still significantly related to PCa’s progression, and the glutamine level which was significantly higher in OM-HSPC compared to other groups. Remarkably, after CIRT treatment, the glutamine levels in OM-HSPC were significantly reduced to the level of healthy samples. Experiments further confirmed CIRT’s ability to suppress glutamine levels in PCa tumors and its potential enhancement with glutamine deprivation intervention.ConclusionCIRT with naADT might synergistically inhibit HS-OMPC development, progression and even the ADT resistance through glutamine metabolism repression, moreover, the glutamine metabolism might be a novel target to further improved the efficacy of CIRT
Autophagy Is a Defense Mechanism Inhibiting Invasion and Inflammation During High-Virulent Haemophilus parasuis Infection in PK-15 Cells
Bacterial infections activate autophagy and autophagy restricts pathogens such as Haemophilus parasuis through specific mechanisms. Autophagy is associated with the pathogenesis of H. parasuis. However, the mechanisms have not been clarified. Here, we monitored autophagy processes using confocal microscopy, western blot, and transmission electron microscopy (TEM) and found that H. parasuis SH0165 (high-virulent strain) but not HN0001 (non-virulent strain) infection enhanced autophagy flux. The AMPK/mTOR autophagy pathway was required for autophagy initiation and ATG5, Beclin-1, ATG7, and ATG16L1 emerged as important components in the generation of the autophagosome during H. parasuis infection. Moreover, autophagy induced by H. parasuis SH0165 turned to fight against invaded bacteria and inhibit inflammation. Then we further demonstrated that autophagy blocked the production of the cytokines IL-8, CCL4, and CCL5 induced by SH0165 infection through the inhibition of NF-κB, p38, and JNK MAPK signaling pathway. Therefore, our findings suggest that autophagy may act as a cellular defense mechanism in response to H. parasuis and provide a new way that autophagy protects the host against H. parasuis infection
Lattice Calculation of the Intrinsic Soft Function and the Collins-Soper Kernel
We calculate the soft function using lattice QCD in the framework of large
momentum effective theory incorporating the one-loop perturbative
contributions. The soft function is a crucial ingredient in the lattice
determination of light cone objects using transverse-momentum-dependent (TMD)
factorization. It consists of a rapidity-independent part called intrinsic soft
function and a rapidity-dependent part called Collins-Soper kernel. We have
adopted appropriate normalization when constructing the pseudo-scalar meson
form factor that is needed in the determination of the intrinsic part and
applied Fierz rearrangement to suppress the higher-twist effects. In the
calculation of CS kernel we consider a CLS ensemble other than the MILC
ensemble used in a previous study. We have also compared the applicability of
determining the CS kernel using quasi TMDWFs and quasi TMDPDFs. As an example,
the determined soft function is used to obtain the physical TMD wave functions
(WFs) of pion and unpolarized iso-vector TMD parton distribution functions
(PDFs) of proton.Comment: 24 pages, 19 figures, published versio
Nonperturbative determination of the Collins-Soper kernel from quasitransverse-momentum-dependent wave functions
In the framework of large-momentum effective theory at one-loop matching accuracy, we perform a
lattice calculation of the Collins-Soper kernel, which governs the rapidity evolution of transversemomentum-dependent (TMD) distributions. We first obtain the quasi-TMD wave functions at three
different meson momenta, on a lattice with valence clover quarks on a dynamical highly improved
staggered quark sea and lattice spacing a ¼ 0.12 fm from the MILC Collaboration, and renormalize the
pertinent linear divergences using Wilson loops. Through one-loop matching to the light-cone wave
functions, we determine the Collins-Soper kernel with transverse separation up to 0.6 fm. We study the
systematic uncertainties from operator mixing and scale dependence, as well as the impact from higher
power corrections. Our results potentially allow for a determination of the soft function and other
transverse-momentum-dependent quantities at one-loop accuracy
Pion and Kaon Distribution Amplitudes from Lattice QCD
We present a state-of-the-art lattice QCD calculation of the pion and kaon light-cone distribution amplitudes (DAs) using large-momentum effective theory. The calculation is done at three lattice spacings a≈{0.06,0.09,0.12}  fm and physical pion and kaon masses, with the meson momenta Pz={1.29,1.72,2.15}  GeV. The result is nonperturbatively renormalized in a recently proposed hybrid scheme with self-renormalization, and extrapolated reliably to the continuum as well as the infinite momentum limit. We find a significant deviation of the pion and kaon DAs from the asymptotic form, and a large SU(3) flavor breaking effect in the kaon D
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