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In this paper, with (Σ, g) being a closed Riemann surface, we analyze the possible concentration behavior of a heat flow related to the Trudinger-Moser energy. We obtain a long time existence for the flow. And along some sequence of times tk → + ∞, we can deduce the convergence of the flow in H2(Σ). Furthermore, the limit function is a critical point of the Trudinger-Moser functional under certain constraint. [ABSTRACT FROM AUTHOR]

Objectives: Biomimetic mineralization mediated by proteins and peptides is a promising strategy for enamel repair, and its specific application model needs more research. In this work, we exploited a liposomal delivery system for a novel peptide (DK5) derived from histatin-1 (DK5-Lips) as a new biomimetic mineralization strategy against initial enamel caries. Materials and methods: The DK5-Lips was prepared using calcium acetate gradient method and then the in vitro release, salivary stability, and cytotoxicity were studied. Initial enamel caries was created in bovine enamel blocks and subjected to pH-cycling model treated with DK5-Lips. Surface microhardness testing, polarized light microscopy (PLM), and transverse microradiography (TMR) were analyzed. Then the biocompatibility of DK5-Lips was evaluated in the caries model of Sprague–Dawley rats, and the anti-caries effect was assessed using Micro-CT analysis, Keyes scores, and PLM in vivo. Results: DK5-Lips provided a mean particle size of (97.63 ± 4.94)nm and encapsulation efficiency of (61.46 ± 1.44)%, exhibiting a sustained release profile, excellent stability in saliva, and no significant toxicity on human gingival fibroblasts (HGFs). The DK5-Lips group had higher surface microhardness recovery, shallower caries depth, and less mineral loss in bovine enamel. Animal experiments showed higher volume and density values of residual molar enamel, lower Keyes score, and shallower lesion depth of the DK5-Lips group with good biocompatibility. Conclusion: As a safe and effective application model, DK5-Lips could significantly promote the remineralization of initial enamel caries both in vitro and in vivo. Clinical relevance: The potential of liposome utilization as vehicle for oral delivery of functional peptides may provide a new way for enamel restoration. [ABSTRACT FROM AUTHOR]

Under constant-stress accelerated life test, the general progressive type-II censoring sample and the two parameters following the linear Arrhenius model, the point estimation and interval estimation of the two parameters log-normal distribution were discussed. The unknown parameters of the model as well as reliability and hazard rate functions are estimated by using Maximum likelihood (ML) and Bayesian methods. The maximum-likelihood estimates are derived by the Newton–Raphson method and the corresponding asymptotic variance is derived by the Fisher information matrix. Since the Bayesian estimates (BEs) of the unknown parameters cannot be expressed explicitly, the approximate BEs of the unknown parameters. The approximate highest posterior density confidence intervals are calculated. The practicality of the proposed method is illustrated by simulation study and real data application analysis. [ABSTRACT FROM AUTHOR]

A copper(II) Schiff-base complex [CuL·2MeOH·HO] was prepared by reaction of the ligand [HL = N, N′- o-phenylene-bis(3-methoxysalicylideneimine)] and Cu(OAc)·HO in methanol at 328.15 K. X-ray diffraction analysis revealed that the title complex was crystallized in the triclinic crystal system with space group P-1, in which copper(II) ion was located in the NO ligand binding sites. According to two designed thermochemical cycles, the dissolution enthalpies of relevant substances of two reactions in the calorimetric solvents were determined by a solution-reaction isoperibol calorimeter, respectively. Combined with some other auxiliary thermodynamic data, the standard molar enthalpies of formation of the ligand and the complex were calculated to be: $$ \Delta_{\text{f}} H_{\text{m}}^{\theta } $$ [HL(s), 298.15 K] = −(384.2 ± 9.10) kJ mol and $$ \Delta_{\text{f}} H_{\text{m}}^{\theta } $$ [CuL·2MeOH·HO (s), 298.15 K] = −(1072.6 ± 9.2) kJ mol. [ABSTRACT FROM AUTHOR]

Toll-like receptor 4 (TLR4) is an important trigger of the immune response against hepatitis B virus (HBV) infection and liver injuries. The roles of HBV reactivation versus TLR4-dependant immune response may be critical factors in preventing radiation-induced liver diseases (RILDs) after liver cancer radiotherapy. This study consists of three phases. In the primary phase, livers of mutant TLR4 (TLR4) mice were irradiated with 30 Gy in either the absence or presence of HBV infection. The latter was done by introduction of plasmid pAAV/HBV 1.2. In the advanced phase, RILDs were compared in normal TLR4 (TLR4) versus TLR4 mice. In the validation phase, 28 liver cancer patients who had undergone radiotherapy before hepatectomy were enrolled. Liver biopsies near tumors, irradiated with 35-48 Gy, were used to construct tissue microarrays. HBV reactivation, TLR4 expression, and severity of RILDs were studied in both mouse and human. More HBV reactivation, without significant RILD, was observed in irradiated versus unirradiated TLR4 mice. RILD scores of TLR4 mice were higher than TLR4 mice. In humans, serious RILDs tended to develop in patients with high TLR4 expression, but not in patients with low TLR4 or high HBV surface antigen expression. High TLR4 expression was seen in only 2 of 12 HBV-reactive patients, but in HBV-nonreactive patients, it was seen in 6 of 9 ( P < 0.03). In summary, RILDs correlated with high TLR4 expression, but not with HBV reactivation, which is inhibited in liver with high TLR4 expression after liver cancer radiotherapy. [ABSTRACT FROM AUTHOR]

In this study, we consider the Bayesian estimation of unknown parameters and reliability function of the generalized exponential distribution based on progressive type-I interval censoring. The Bayesian estimates of parameters and reliability function cannot be obtained as explicit forms by applying squared error loss and Linex loss functions, respectively; thus, we present the Lindley's approximation to discuss these estimations. Then, the Bayesian estimates are compared with the maximum likelihood estimates by using the Monte Carlo simulations. [ABSTRACT FROM AUTHOR]

Ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) is a putative tumor suppressor that is correlated with many human cancers. However, the function of EBP50 in pancreatic cancer (PC) has not been described. In this paper, the EBP50 expression level in PC tissues was characterized. In vitro, the effects of EBP50 down-regulation by siRNA in PC-2 and MiaPaCa-2 cells were evaluated. In addition, possible mechanisms that mediate the influence of EBP50 were examined. Our results show that the EBP50 expression pattern changes during transformation as there is a loss of the normal apical membrane distribution and an ectopic cytoplasmic over-expression of EBP50; furthermore, the EBP50 expression level is subsequently decreased during malignant progression. Down-regulation of EBP50 promoted cancer cell proliferation, increased the colony-forming ability of cells and accelerated the G1-to-S progression. Additionally, the loss of EBP50 accentuated β-catenin activity, increased cyclin E and phosphorylated Rb expression, and attenuated p27 expression compared to control cells. Our results suggest that EBP50 may function as a potential tumor suppressor. [ABSTRACT FROM AUTHOR]

sensitive and specific liquid chromatography-electrospray ionization-tandem mass spectrometry method has been developed and validated for the identification and quantification of ursolic acid in human plasma using glycyrrhetic acid as an internal standard. The method involves extraction with methyl tert-butyl ether. The analyte was separated on a C column and analyzed in multiple reaction monitoring mode with a negative electrospray ionization interface using the [M-H]− ions, m/ z 455.4 for ursolic acid and m/ z 469.5 → m/ z 425.5 for glycyrrhetic acid. The method was validated over the concentration range of 0.86-110.0 μg L. The intra- and inter-day precisions were less than 13.53% relative standard deviation (RSD) and the accuracy was within −4.76% in terms of relative error (RE). The lower limit of quantification was 0.86 μg L with acceptable precision and accuracy. There were almost no matrix effects. Recovery of ursolic acid from spiked drug-free plasma was higher than 68%. The method was used to study the pharmacokinetic profile of ursolic acid in human plasma after oral administration of Jieyu capsules. [ABSTRACT FROM AUTHOR]

In this article, based on river quality simulation and system optimization, a water quality model was established for scenic river after rainfall discharge in flood season, with the target of making water pollutants meet the standard in priority and saving expenditure on pollution control. With the principle of reducing sewage from combined sewage pumping station and heavily polluted initial rainwater, a mathematical multiobjective planning model was constructed for rain sewage pollution control in flood season, and one scenic river in a northern city was taken for simulation example. The results show that: the optimization result meets the requirements of planning, among which, sewage reduction from the combined pumping station accounts for 17.38% in the total reduction of rain sewage, and the reduction in the heavily polluted rain water accounts for 77.24% in the total reduction of rainwater pumping station. The planning scheme can provide theoretical basis for pollution control of scenic river in flood season, and for rational reconstruction and layout of outfalls along two banks of the river. [ABSTRACT FROM AUTHOR]

Time series of sea surface temperature (SST), wind speed and significant wave height (SWH) from meteorological buoys of the National Data Buoy Center (NDBC) are useful for studying the interannual variability and trend of these quantities at the buoy areas. The measurements from 4 buoys (B51001, B51002, B51003 and B51004) in the Hawaii area are used to study the responses of the quantities to EI Niño and Southern Oscillation (ENSO). Long-term averages of these data reflect precise seasonal and climatological characteristics of SST, wind speed and SWH around the Hawaii area. Buoy observations from B51001 suggest a significant warming trend which is, however, not very clear from the other three buoys. Compared with the variability of SST and SWH, the wind speeds from the buoy observations show an increasing trend. The impacts of EI Niño on SST and wind waves are also shown. Sea level data observed by altimeter during October 1992 to September 2006 are analyzed to investigate the variability of sea level in the Hawaii area. The results also show an increasing trend in sea level anomaly (SLA). The low-passed SLA in the Hawaii area is consistent with the inverse phase of the low-passed SOI (Southern Oscillation Index). Compared with the low-passed SOI and PDO (Pacific Decadal Oscillation), the low-passed PNA (Pacific-North America Index) has a better correlation with the low-passed SLA in the Hawaii area. [ABSTRACT FROM AUTHOR]

The interaction of heparin with toluidine blue (TB) was studied by voltammetry. In pH 5.8 Britton-Robinson (BR) buffer, heparin, which is negatively charged, easily binds to the positively charged TB to form a polyelectrolyte complex. Due to the formation of the complex, the well-defined redox peaks of TB at the glass carbon electrode decreased correspondingly without the movement of the peak potential after the addition of heparin. The reaction conditions were optimized carefully. Based on the decrease of the peak current of TB solution, a new electrochemical analytical method was established for heparin with a linear range from 1.0 to 20.0 µg mL−1 and a detection limit of 0.44 µg mL−1. The relative standard deviation (RSD) for five parallel determinations of 10.0 µg mL−1 heparin was 1.07%. This new method was applied to the determination of heparin in heparin sodium injection samples with satisfactory results. [ABSTRACT FROM AUTHOR]

Based on the in situ optical measurements in the Bohai Sea of China, which belongs to a typical case-2 water area, we studied the characteristics of DCM (deep chlorophyll maximum) such as its spatial distribution, vertical profile, etc. We found that when the depth of the chlorophyll maximum is comparatively small, even in turbid coastal water regions, there is always a good correlation between the concentrations of chlorophyll maximum and the satellite-received signals in blue-green spectral bands; the correlation is even better than that between the surface chlorophyll concentrations and the satellite-received signals. The strong correlation existing even in turbid coastal water regions indicates that an ocean color model to retrieve the concentration of DCM can be constructed for coastal waters if a comprehensive knowledge of the vertical distribution of chlorophyll concentration in the Bohai Sea of China is available. [ABSTRACT FROM AUTHOR]