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Xe/Kr separation is industrially important but remains a daunting issue in chemical separations. Herein, a fluorinated metal-organic framework (MOF), [Ni

Soil is the largest carbon reservoir in terrestrial ecosystems, and thus minor changes in it can dramatically affect atmospheric CO concentrations. The fragile ecological environment in the northwestern arid zone of China is susceptible to natural and anthropogenic disturbances, which lead to variations in structure and function of the ecosystem, as well as carbon source–sink dynamics. In this study, digital soil maps of soil organic carbon stocks (SOCS) were produced at a 90-m resolution for two periods (the 1980s and 2010s) based on historical soil profile data and a random forest model. The results showed that the prediction accuracy for SOCS in the topsoil (0–30 cm) was superior to that of the subsoil (30–100 cm). Among them, the mean annual evapotranspiration, normalized difference vegetation index during the growing season, multi-year mean temperature, and clay content were the main environmental factors affecting the spatial distribution of SOCS. In the past 30 years, the SOCS of the northwestern arid zone have decreased by 585.50 Tg, with a mean decline of 19.52 Tg C yr . The changes in SOCS caused by land-use conversion and reductions in SOCS were further shown to be attributable to grassland desertification and agricultural reclamation. These findings are valuable for exploring the carbon cycle in terrestrial ecosystems in the context of global climate change and for achieving China’s goal of carbon neutrality.

OBJECTIVE To investigate color Doppler ultrasonography criteria and its value in assessing the steno-occlusion of the terminal internal carotid artery in moyamoya disease. METHODS According to the digital subtraction angiography findings, patients were divided into three groups: occlusion of the terminal internal carotid artery, >50% stenosis, and ≤50% stenosis. We measured the terminal and proximal internal carotid artery parameters of each group using transcranial and cervical color Doppler sonography. RESULTS Blood flow signals in 12 terminal internal carotid arteries were absent, which were verified as occlusion by digital subtraction angiography. Parameters were obtained in the remaining 159 terminal/proximal internal carotid arteries to predict cutoffs for >50% stenosis and occlusion. For >50% stenosis, mean flow velocity >88.50 cm/s in the terminal internal carotid artery could achieved the highest receiver operating characteristic curve area of 0.776 with 62.50% sensitivity, 88.15% specificity, 48.39% positive predictive values, 92.97% negative predictive value, and 84.27% overall accuracy. For the occlusion, mean flow velocity

OBJECTIVE The aim of this study was to determine how hemodynamics of the posterior cerebral artery (PCA) are associated with cerebral ischemic lesions in moyamoya disease (MMD). METHODS Thirty-six patients with ischemic MMD (Suzuki grade IV-V) were retrospectively analyzed. Hemodynamic parameters of the PCA were measured by transcranial color-coded sonography. We classified the range of ischemic lesions into 3 grades and perfusion levels into 3 grades according to computed tomography (CT) results. PCA steno-occlusion and leptomeningeal collaterals were confirmed by digital subtraction angiography. Ultrasonographic parameters in the PCA were compared with these radiographic findings. RESULTS The velocity in the involved PCA (mean flow velocity [MFV] median, 42.00 [range, 34.50-58.00] cm/s) was significantly lower than that in the normal PCA (MFV median, 95.00 [range, 76.50-119.50] cm/s) (P

Aerosol optical depth (AOD) describes the attenuation of light by aerosols and reflects the degree of regional air pollution to some extent. This study was based on the data from the long-term sequence MOD09A1 from 2000 to 2015 and the generation of a lookup table using the deep blue algorithm (DB) to perform AOD remote sensing estimation on the Landsat TM/ETM+/OLI data from the Ebinur Lake Basin to analyze the temporal and spatial variation characteristics of AOD in the Ebinur Lake Basin and to perform an AOD prediction and factor contribution ranking using the random forest model (RF) combined with environmental variables. The results showed that:① AOD of Ebinur Lake Basin has significant seasonal variation characteristics, and the AOD values were spring (0.414)summer (0.390)autumn (0.287), with the largest variation in spring. ② The AOD average of the Ebinur Lake Basin was 0.374, and the interannual variation as a whole showed an upward trend. However, the AOD increased rapidly during 2010-2015, with an interannual increase of 32.32%, which indicated increasing air pollution in the basin over the past 15 years, especially the past five years. ③ The spatial distribution of AOD in the Ebinur Lake Basin was stepped up from the north to the south of Lake Ebinur. In this area, the pollution in Jinghe County was the most prominent, and the AOD value reached 0.483. ④ The RF model had a good predictive effect on AOD

In this paper, porous anodic aluminum oxide (AAO) membrane was prepared with highly pure aluminum film in 0.3M oxalic acid under dc voltage of 40V at about 8°C by two-step anodization. The morphology of the specimens processed in different stages of two-step anodization was observed with a scanning electron microscope (SEM). The electrochemical behavior of the anodized aluminum after different stages of two-step anodization was studied by electrochemical impedance spectroscopy (EIS). Different equivalent circuits were established to fit EIS experiment data, based on morphologies and structures of AAO during processing. The electrical elements in the equivalent circuits were used to explain experimental parameters.

In this paper, effect of oxygen partial pressure on formation of Fe2O3 nanostructure during Thermal Oxidation was studied. Fe2O3 nanostructure was formed by controlling oxidation conditions (Po2) and using the method of thermal oxidation. To begin with, a piece of pure iron in a ceramic crucible was put in the tube furnace (SYS-G-Z-13). Next the metallic Fe was oxidized at 500°C for 4 hours, under different oxygen partial pressure including pure argon (Po2 = 0atm), air Po2 = 0.21atm) and pure oxygen (Po2 = 1atm) to produce nanostructure, respectively. The surface morphology of the oxidized specimens was observed by SEM. The crystalline structure of the nanostructure was determined by transmission electron microscope. The experimental results show that the density of nanosheets increases with increasing oxygen partial pressure.

Sol-gel method is used for the formation of Pb0.499Sr0.499TiO3 (PST)thin films. The initial films were prepared with spin coating sol solution on silicon wafer and drying at room temperature and then heating coated dry sol film at 400°C for 10min. This process was repeated for 1-4 times to obtain 4 initial films with different thicknesses. The 4 initial films were annealed at 700°C for 2h to obtain PST ceramics films. The morphologies of the surface and cross-section of PST films were observed with a scanning electronic microscope (SEM). The phase structures of PST films were analyzed using X-ray diffraction meter (XRD). Experimental results show that PST film prepared by coating sol on silicon with different thicknesses can be high smooth,uniform and compact film.

Harpagoside, an iridoid glycoside, is the major bioactive constituent of the traditional Chinese medicine Scrophulariae Radix. High-performance liquid chromatography with a diode array detector combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry (HPLC-ESI-IT-TOF-MSn ) was used to profile and identify the metabolites of harpagoside in rats in vivo and to study the distribution of these metabolites in rats for the first time. A total of 45 metabolites were identified, 37 of which were postulated to be new compounds. The number of detected metabolites in the heart, liver, spleen, lung, kidney, stomach and small intestine was 2, 9, 6, 16, 4, 16 and 6, respectively, which indicated that the target organs of harpagoside should be spleen, lung and stomach. The main types of metabolic reactions of harpagoside in rats are hydrolysis, reduction, sulfuric acid addition, hydroxylation, methoxylation, sulfate substitution, methylation, glucose conjugation and amino acid conjugation. Furthermore, 23 metabolites were determined to have bioactivities based on the literature and 'PharmMapper' analysis. These findings are useful for better comprehension of the effective forms, target organs and pharmacological effects of harpagoside. Moreover, these findings provide a reference for studying the metabolism and distribution of iridoid compounds.

This experiment was performed to establish a qualitative analysis on chemical constituents of Scrophulariae Radix by HPLC-ESI-IT-TOF-MS．The analysis was conducted on a C₁₈ column (Kromasil 100-5, 4.6 mm×250 mm, 5 μm) with 0.1% formic acid-acetonitrile as the mobile phase for gradient elution; ESI ion source was used for mass spectra, and data were collected innegative and positive modes. The results showed that 64 compounds from Scrophulariae Radix had been identified by analyzing negative ion mass data including element composition and by comparing with data from literature. Two new compounds (4-hydroxy-6-O-methylcatalpol and acetylangoroside C) and seventeen known compounds were detected from Scrophulariae Radix for the first time. Seventeen known compounds included twelve iridoid glycosides, three phenylpropanoid glycosides and two other kind compounds. This study will provide chemical basis for elucidation of the effective substance in the Scrophulariae Radix.

Liver transplantation is associated with a significantly increased risk of de novo malignancies, but for renal cancer this risk is less clear. We therefore performed a meta-analysis of published studies to determine whether renal cancer risk in liver transplant recipients (LTRs) was increased. To obtain a more precise conclusion, a systematic search was performed in PubMed and Web of Science databases until June 10, 2015. Standardized incidence ratio (SIR) corresponding 95% confidence interval (CI) were used to estimate risk of renal cancer in LTRs. Heterogeneity test, sensitivity analysis, and publishing bias were also performed. We identified 8 eligible studies and performed a meta-analysis on data of 49,654 LTRs with a total follow-up of 121,514.6 patient-years. The SIR for renal cancer was identified a 3.275-fold higher SIR (95% CI: 1.857-5.777; P

8-Prenylkaempferol is a prenylflavonoid that has various bioactivities and benefits for human health. A high-performance liquid chromatography with a diode array detector combined with electrospray ionization ion trap time-of-flight multistage mass spectrometry (HPLC-DAD-ESI-IT-TOF-MS(n) ) method was established to profile and identify the metabolites of 8-prenylkaempferol in rat in vivo and in vitro, and to study the distribution of these metabolites in rats for the first time. A total of 38 metabolites were detected and tentatively identified, 30 of which were identified as new compounds. The new in vivo metabolic reactions in rats of prenylflavonoids of isomerization, polymerization, sulfation, amino acid conjugation, vitamin C conjugation and other known metabolic reactions were found in the metabolism of 8-prenylkaempferol. The numbers of detected metabolites in feces, urine, plasma, small intestine, stomach, kidneys, liver, heart, lungs, spleen and hepatic S9 fraction were 31, 19, 1, 20, 13, 8, 7, 3, 3, 1 and 11, respectively. This indicated that small intestine and stomach were the major organs in which the 8-prenylkaempferol metabolites were distributed. Furthermore, 16 metabolites were determined to have bioactivities based on the literature and 'PharmMapper' analysis. These findings are useful for better comprehension of the effective forms, target organs and pharmacological actions of 8-prenylkaempferol. Moreover, they provide a reference for the study of the metabolism and distribution of prenylflavonoid aglycone compounds.

The purpose of this study was to assess the efficacy and toxicity of HAI regimen [(homoharringtonine 2.5 mg/(m(2)×d), days 1 - 7; cytarabine 150 mg/(m(2)×d), days 1 - 7; idarubicin 9 mg/(m(2)×d), days 1 - 7)] for induction treatment of newly diagnosed acute myeloid leukemia (AML) (except acute promyelocytic leukemia). 31 patients with newly diagnosed AML, aged 39 (14 - 58) years, were enrolled in this clinical study. The complete remission (CR) rate, especially after one course, the overall survival (OS) rate and relapse free survival (RFS) rate were estimated. The outcomes were compared between different prognostic groups according to World Health Organization (WHO) classification, genetics and initial WBC count. Safety was evaluated using standard WHO criteria. The results showed that 26 patients (84%) achieved CR after 1 course of induction. The CR rate for the patients with favorable, intermediate and unfavorable cytogenetics was 90%, 88% and 60% respectively. All 7 patients with a high initial WBC count (≥ 100×10(9)/L) obtained CR, while 19 out of 24 without a high initial WBC count obtained CR. With a median follow-up of 15(range 2-56) months, the estimated 3-year OS rate for all patients and the patients with CR was 44% and 52% respectively. The 3-year RFS rate was 51%. The patients receiving induction chemotherapy died of the chemotherapy. Profound myelosuppression was seen in all patients after the HAI induction with the median duration of neutropenia (ANC0.2×10(9)/L) of 16 (6 - 24) days. As the most common toxicity, severe infections (grade III-IV) involved in all the patients and the duration of febris was 6 (1 - 36) days. The incidence of septemia and invasive fungus infection were 19.4% and 45.2% respectively. The incidence of non-infection fever, increased glutamic-pyruvic transaminase (GPT), diarrhea, increased bilirubin and oral cavity mucositis were 6.5%, 6.5%, 3.2%, 3.2%, 3.2% respectively, as the more frequent severe non-hematological toxicities. It is concluded that HAI regimen is a high efficient induction schedule for the newly diagnosed AML, and archive the higher CR rate after one course than DNR/Ara-C standard induction regimen. Side effects are acceptable, except severe infection.