[en] Diffusion tensor imaging (DTI) can be used to measure the diffusional motion of water molecules, and can provide a unique source of contrast among tissues. Diffusion kurtosis imaging (DKI) provides quantifiable information on the non-Gaussian behavior of water diffusion in biological tissue, and discloses subtle substructural changes. DKI can provide more information than DTI does. In this article, we reviewed the basic principle and preliminary application of DKI in central nervous system, including neurodegenerative disease, traumatic brain injury, cerebral ischemic stroke, glioma, multiple sclerosis, and brain maturation. (authors)

[en] This paper studies the support and hanger layout in complex piping, and make sure the operation of the system pipeline under different working conditions. Using the method of numerical calculation with CFD could summarize the process and method of support and hanger layout. An example is given to verify the effectiveness. (authors)

[en] Hepatic encephalopathy (HE) is an important complication of end-stage cirrhosis which can leads to a series of neurological and cognitive changes. Liver transplantation (LT) can effectively restore the liver function, thus the impaired cognitive function can be greatly corrected. MRI offers a variety of techniques for non-invasive evaluation of alterations in metabolism, cognition, and structures of brain in the cirrhotic patients after LT. In this article, we reviewed the current research status concerning post-surgery cognitive alterations, as well as the application of multimodal magnetic resonance imaging in assessing brain alterations after LT, and its value in revealing the neurological mechanism underlying the recovery and residual impairment of cognitive. (authors)

[en] To evaluate the spontaneous brain activity alterations in liver transplantation (LT) recipients using resting-state functional MRI. Twenty cirrhotic patients as transplant candidates and 25 healthy controls (HCs) were included in this study. All patients repeated the MRI study one month after LT. Amplitude of low-frequency fluctuation (ALFF) values were compared between cirrhotic patients (both pre- and post-LT) and HCs as well as between the pre- and post-LT groups. The relationship between ALFF changes and venous blood ammonia levels and neuropsychological tests were investigated using Pearson's correlation analysis. In the cirrhotic patients, decreased ALFF in the vision-related regions (left lingual gyrus and calcarine), sensorimotor-related regions (left postcentral gyrus and middle cingulate cortex), and the default-mode network (bilateral precuneus and left inferior parietal lobule) were restored, and the increased ALFF in the temporal and frontal lobe improved in the early period after LT. The ALFF decreases persisted in the right supplementary motor area, inferior parietal lobule, and calcarine. The ALFF changes in the right precuneus were negatively correlated with changes in number connection test-A scores (r = 0.507, p < 0.05). LT improved spontaneous brain activity and the results for associated cognition tests. However, decreased ALFF in some areas persisted, and new-onset abnormal ALFF were possible, indicating that complete cognitive function recovery may need more time

[en] Six new coordination polymers, [ZnLCl]_n(1), [ZnL_2]_n·2nH_2O (2), [Zn_2L(o-bdc)(OH)]_n·0.5nH_2O (3), [Zn_2L(m-bdc)(OH)]_n·nH_2O (4), [Zn_2L_2(p-bdc) (H_2O)_2]_n·nH_2O (5), [Zn_2L(1,2,4-btc)(H_2O)]_n(6), (HL=4′-(3-carboxyphenyl)- 3,2′:6′,3″-terpyridine, H_2(o-bdc)= benzene-1,2-dicarboxylic acid, H_2(m-bdc)= benzene-1,3-dicarboxylic acid, H_2(p-bdc)= benzene-1,4-dicarboxylic acid, H_3(1,2,4-btc)= benzene-1,2,4-tricarboxylic acid) have been synthesized under the hydrothermal conditions. Compound 1 displays a 3-connected 2D network structure with point symbol of {8"2.10}. Compound 2 exhibits 1D infinite loop chain structure. Compound 3 possesses a (3,8)-connected 3D framework composed of tetranuclear units with point symbol of {4"3}_2{4"6.6"1"8.8"4}. Compound 4 features a typical 2D hcb network based on tetranuclear zinc(II) units with point symbol of {4"4.6"2}. Compound 5 presents a classical two-fold penetration sql network with point symbol of {6"3}. Compound 6 can be seen as a (3,3,6)-connected 3D net with point symbol of {4"2.6"4.8"9}{4"2.6}{6"3}. The thermal stability and luminescent properties of compounds 1–6 in the solid state are discussed in detail. - Graphical abstract: Six new Zn(II) coordination polymers based on multicarboxylate and terpyridyl derivative ligands have synthesized under the hydrothermal conditions and the thermal stability and luminescence are discussed. Display Omitted

[en] To describe the multiparametric magnetic resonance imaging (MRI) appearance of prostate tuberculosis. Six patients with prostate tuberculosis were analyzed retrospectively. The mean age of the patients was 60.5 years (range, 48-67 years). The mean prostate specific antigen concentration was 6.62 ng/mL (range, 0.54-14.57 ng/mL). All patients underwent a multiparametric MRI examination. The histopathological results were obtained from biopsies in four men and from transurethral resection of the prostate in two men after the MRI examination. Nodular (33%, 2/6 patients) and diffuse lesions (67%, 4/6 patients) were seen on MRI. The nodular lesions were featured by extremely low signal intensity (similar to that of muscle) on T2-weighted imaging (T2WI). The T2WI signal intensity of the diffuse lesions was low but higher than that of muscle, which showed high signal intensity on diffusion weighted imaging and low signal intensity on an apparent diffusion coefficient map. MR spectroscopic imaging of this type showed a normal-like spectrum. Abscesses were found in one patient with the nodular type and in one with the diffuse type. The appearance of prostate tuberculosis on MRI can be separated into multiple nodular and diffuse types. Multiparametric MRI may offer useful information for diagnosing prostate tuberculosis

[en] Objective: To explore the efficacy difference of diffusion kurtosis imaging (DKI) and ultrasound elastography (UE) in the diagnosis of liver fibrosis. Methods: Thirty-five patients whose serological examination showed hepatitis B or hepatitis C virus infection, disease course ≥ 1 year, and finally liver biopsy confirmed pathological fibrosis grade in Tianjin Second People's Hospital from December 2015 to April 2017 were prospectively enrolled as patient group. During the same period, twenty healthy volunteers who matched the age, sex and BMI with patient group and showed normal liver function within the last month were enrolled as control group. All of the subjects underwent DKI experiment, and subjects in patient group underwent UE experiment in addition. Liver mean apparent diffusion (MD) and mean kurtosis (MK) were obtained in all subjects and liver stiffness measurement (LSM) was obtained in patient group. The patient group was staged for hepatic fibrosis based on liver biopsy results (S0 to S4). Differences in liver MD and MK values between control and patient groups were tested using independent sample t test (normal distribution) or Mann-Whitney U test (skewed distribution). Differences in liver MD, MK, and LSM between patients with different fibrosis stages were tested using One-way ANOVA (normal distribution) or Kruskal-Wallis test (skewed distribution). The correlation between liver MD, MK and LSM values with fibrosis stages were analyzed using Pearson correlation test. The diagnostic performance in staging fibrosis was analyzed using ROC analysis. Results: Liver MD in patient group was lower than that in control group, and the difference was statistically significant (P < 0.01). There was no significant difference in liver MK between the two groups (P > 0.05). The AUC value for the diagnosis of liver fibrosis by MD was 0.950 (95% CI: 0.855 to 0.990). Of the 35 patients, 15 were S1 (mild fibrosis), 13 were S2 (moderate fibrosis), 4 were S3, 3 were S4 (S3 + S4 were severe fibrosis). The difference of MD and LSM between different stages of liver fibrosis was statistically significant (P < 0.05), and there was no significant difference in MK (P > 0.05). Liver fibrosis stages was highly correlated with MD (r = -0.757, P < 0.01), and had no correlation with MK (r = -0.010, P = 0.956), and moderately correlated with LSM (r = 0.440, P < 0.01). The AUC values of liver MD and LSM for characterization of ≥ S2 stage liver fibrosis were 0.867 and 0.800, respectively, without statistically significant difference (P = 0.486). The AUC values for characterization of ≥ S3 stage liver fibrosis were 0.918 and 0.653, respectively, with a statistically significant difference (P = 0.032). Conclusion: MD derived from DKI can be used for noninvasive assessment of liver fibrosis, and it is superior to LSM in distinguishing different fibrosis stages and detecting severe fibrosis. (authors)

[en] Breakdown in ablative pulsed plasma thrusters (APPTs) must be studied in order to design new types of APPTs and measure particular parameters. In this paper, we studied a parallel-plate ablative pulsed plasma thruster that used a coaxial semiconductor spark plug. By operating the APPT about 500 times with various capacitor voltages and electrode gaps, we measured and analyzed the voltage of the spark plug, the voltage between the electrodes, and the discharge current. These experiments revealed a time delay (∼1–10 μs) between spark plug ignition and capacitor discharge, which may affect the performance of high-pulsing-rate (>10 kHz) and double-discharge APPTs, and the measurements of some of the APPT parameters. The delay time decreased as the capacitor voltage increased, and it increased with an increasing electrode gap and increasing number of ignitions. We explain our results through a simple theoretical analysis

[en] We study the P-V criticality and phase transition in the extended phase space of anti-de Sitter (AdS) black holes in higher-dimensional de Rham, Gabadadze and Tolley (dRGT) massive gravity, treating the cosmological constant as pressure and the corresponding conjugate quantity is interpreted as thermodynamic volume. Besides the usual small/large black hole phase transitions, the interesting thermodynamic phenomena of reentrant phase transitions (RPTs) are observed for black holes in all d ≥ 6-dimensional spacetime when the coupling coefficients c_im"2 of massive potential satisfy some certain conditions. (orig.)

[en] The Pt/Si/Ta/Ti multilayer metal contacts on 4H–SiC are annealed in Ar atmosphere at 600 °C–1100 °C by a rapid thermal processor (RTP). The long-term thermal stability is evaluated by aging the annealed contact at 600 °C in air. The contact’s properties are determined by current–voltage measurement, and the specific contact resistance is calculated based on the transmission line model (TLM). Transmission electron microscope (TEM) and energy-dispersive x-ray spectrometry (EDX) are used to characterize the interface morphology, thickness, and composition. The results reveal that a higher annealing temperature is favorable for the formation of an Ohmic contact with a lower specific contact resistance, and causes the rapid degradation of the Ohmic contact in the aging process. (paper)