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[en] Moessbauer measurements in the temperature range of 12-300 K have been performed on three kinds of new binuclear Fe(III) porphyrin complexes. The Moessbauer spectra similar to that of ferric hemin show the electron spin-spin relaxation process. The relaxation time increases with distance between two porhyrin rings and the results provide an evidence of formation of the complex
[en] In this paper, the holographic dark energy models with the new infrared cutoff for both the flat case and the nonflat case are confronted with the combined constraints of current cosmological observations: type Ia supernovae, baryon acoustic oscillations, current cosmic microwave background, and the observational Hubble data. By utilizing the Markov chain Monte Carlo method, we obtain the best fit values of the parameters with 1σ, 2σ errors in the flat model: Ωbh2=0.0230-0.0010-0.0014+0.0008+0.0012, α=0.9788-0.0927-0.1249+0.1297+0.1354, β=0.4739-0.0723-0.0984+0.0793+0.1055, Ωde0=0.7869-0.0304-0.0455+0.0291+0.0370, Ωm0=0.2131-0.0291-0.0370+0.0304+0.0455, H0=70.46-2.97-4.02+2.82+3.89. In the nonflat model, the constraint results are found in 1σ, 2σ regions: Ωbh2=0.0229-0.0010-0.0014+0.0010+0.0013, Ωk=0.0014-0.0597-0.0743+0.0604+0.0604, α=0.9637-0.2840-0.3333+0.2291+0.2894, β=0.4712-0.0756-0.0961+0.1412+0.1703, Ωde0=0.7829-0.2130-0.2386+0.1588+0.1901, Ωm0=0.2157-0.1012-0.1241+0.1562+0.1800, H0=70.64-3.32-4.45+2.74+3.52. In the best fit holographic dark energy models, the equation of state of dark energy and the deceleration parameter at present are characterized by wde0=-0.9278±0.0626, q0=-0.5951±0.0586 (flat case) and wde0=-0.9501±0.1442, q0=-0.6164±0.0805 (nonflat case). Compared to the ΛCDM model, it is found the current combined data sets do not favor the holographic dark energy model over the ΛCDM model.
[en] In this paper, the Dvali-Gabadadze-Porrati (DGP) brane model is confronted by current cosmic observational data sets from geometrical and dynamical perspectives. On the geometrical side, the recently released Union2 557 of type Ia supernovae (SN Ia), the baryon acoustic oscillation from the Sloan Digital Sky Survey and the Two Degree Galaxy Redshift Survey (transverse and radial to line-of-sight data points), the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations [shift parameters R, la(z*) and redshift at the last scatter surface z*], ages of high redshifts galaxies, i.e., the lookback time and the high redshift gamma ray bursts are used. On the dynamical side, data points about the growth function of matter linear perturbations are used. Using the same data set combination, we also constrain the flat ΛCDM model as a comparison. The results show that current geometrical and dynamical observational data sets much favor the flat ΛCDM model and the departure from it is above 4σ(6σ) for the spatially flat DGP model with (without) SN systematic errors. The consistence of growth function data points is checked in terms of a relative departure of redshift-distance relation.
[en] Most anticancer drugs are effective only in subgroups of patients,which makes the individualization of tumor response monitoring quite in need. Since the current anatomic imaging has certain limitations for this utility, and the clinical evidence of 18F-FDG PET from meta-analysis is increasing, this study gives a comprehensive review of the performance of PET in monitoring response of a variety of tumors. Given the early metabolic characterization of tumors by PET, this technology exhibited special advantages to traditional imaging modalities and generally yielded high accuracies in tumor response assessment in many meta-analyses. In certain type of tumors as malignant lymphoma, PET has recently been placed to a central role in defining tumor response in international criteria. In other tumors as non-small cell lung cancer, breast cancer, esophageal cancer, adenocarcinomas of the esophagogastric junction, rectal cancer and gastrointestinal stromal tumor, questions remain due to lack of standard regimen of PET and heterogeneity between individual study results. Besides, certain numbers of false positive and false negative results of PET still call for caution in clinical scenarios. More prospective and large sampled random trials are warranted to fully validate and position PET in tumor management. (authors)
[en] Diatoms play an important role as ecological indicators, and some species of diatoms can easily cause water blooms, thereby decreasing the production capacity of water treatment plants and endangering drinking water safety. Mastering the diatom community dynamics is crucial for water supply. In this study, diatom composition, spatial distribution and succession were investigated in Datun Reservoir, Donghu Reservoir and Shuangwangcheng Reservoir, which are important drinking water sources in Shandong province, China. Results showed that the three reservoirs could be classified as being between mesotrophic and moderately eutrophic. The diatom community in each of the three reservoirs exhibited no obvious seasonal succession. The diatom communities in the three reservoirs were relatively simple in composition, with Synedra and Cyclotella being the most dominant groups all year round. Synedra had a negative relationship with NO2-N. Cyclotella had a positive association with NO3-N, but was negatively associated with NH4-N and CODMn in the three reservoirs. Through the analysis of diatom and environmental factors, the three reservoirs have the potential of hosting diatom blooms in summer, when the higher temperature combines with reduced water flow.
[en] Objective: To explore the value of CT guided ozone (O3) injection in the ablation treatment of cervical spondylosis. Methods: All 86 patients with cervical spondylosis including 37 myelopathy type, 30 radiculopathy type, and 16 sympathetic type were treated with O3 injection under CT guidance. The puncture rout was from the anteroparaline of neck to the disk. A total of (4 ± 3) ml of O3 with concentration 60 μg/ml was injected into the disk and 10 ml of O3 with concentration 40 μg/ml was injected to the paraspinal tissue. Results: After injection CT scan showed that O3 was distributed within the disk and the protruding part as low-density air shadow in 37 myelopathy type and 30 radiculopathy type patients. O3 was observed to spread in the anterior epidural space of spinal canal and the paraspinal tissue. Three months after O3 injection, 67 patients (78%) showed excellent clinical efficacy, 14 (16%) had good clinical efficacy, and 5 (6%) were poor respectively. Conclusion: CT guided O3 injection is an accurate, safe, and effective method in the treatment of cervical spondylosis. (authors)
[en] We use the Markov Chain Monte Carlo method to investigate global constraints on the generalized holographic (GH) dark energy with flat and non-flat universe from the current observed data: the Union2 dataset of type supernovae Ia (SNIa), high-redshift Gamma-Ray Bursts (GRBs), the observational Hubble data (OHD), the cluster X-ray gas mass fraction, the baryon acoustic oscillation (BAO), and the cosmic microwave background (CMB) data. The most stringent constraints on the GH model parameter are obtained. In addition, it is found that the equation of state for this generalized holographic dark energy can cross over the phantom boundary wde =-1. (orig.)
[en] We perform a global constraint on the Ricci dark energy model with both the flat case and the non-flat case, using the Markov Chain Monte Carlo (MCMC) method and the combined observational data from the cluster X-ray gas mass fraction, Supernovae of type Ia (397), baryon acoustic oscillations, current Cosmic Microwave Background, and the observational Hubble function. In the flat model, we obtain the best fit values of the parameters in 1σ,2σ regions: Ωm0 = 0.2927+0.0420+0.0542−0.0323−0.0388, α = 0.3823+0.0331+0.0415−0.0418−0.0541, Age/Gyr = 13.48+0.13+0.17−0.16−0.21, H0 = 69.09+2.56+3.09−2.37−3.39. In the non-flat model, the best fit parameters are found in 1σ,2σ regions:Ωm0 = 0.3003+0.0367+0.0429−0.0371−0.0423, α = 0.3845+0.0386+0.0521−0.0474−0.0523, Ωk = 0.0240+0.0109+0.0133−0.0130−0.0153, Age/Gyr = 12.54+0.51+0.65−0.37−0.49, H0 = 72.89+3.31+3.88−3.05−3.72. Compared to the constraint results in the ΛCDM model by using the same datasets, it is shown that the current combined datasets prefer the ΛCDM model to the Ricci dark energy model
[en] Inspired by the recent experimental progress in noisy kicked rotor systems, we investigate the effect of temporal disorder or quasi-periodicity in one-dimensional kicked lattices with pulsed on-site potential. We found that, unlike the spatial disorder or quasi-periodicity which usually leads to localization, the effect of the temporal one is more complex and depends on the spatial configuration. If the kicked on-site potential is periodic in real space, then the wave packet will stay diffusive in the presence of temporal disorder or quasi-periodicity. On the other hand, if the kicked on-site potential is spatially quasi-periodic, then the temporal disorder or quasi-periodicity may lead to a shift of the transition point of the dynamical localization and destroy the dynamical localization in a certain parameter range. The results we obtained can be readily tested by experiments and may help us better understand the dynamical localization. (special topic)