Summary
Background
Transient elastography is a non‐invasive method for staging liver fibrosis. The meta‐analysis using the hierarchical models to evaluate the diagnostic accuracy of transient ...elastography for the staging of liver fibrosis in patients with chronic hepatitis B was rarely reported.
Aim
A meta‐analysis using the hierarchical models was performed to assess transient elastography for diagnosing and stage liver fibrosis in patients with chronic hepatitis B.
Methods
Electronic databases were searched and studies were identified to assess the diagnostic accuracy of transient elastography in CHB patients for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 with liver biopsy as a reference standard. The hierarchical summary receiver operating characteristic curve and the bivariate models were performed to evaluate the diagnostic accuracy of transient elastography, and meta‐regression analyses were performed to explore the heterogeneity. The quality Assessment of Diagnostic Accuracy Studies‐2 tool was used to assess the quality of studies.
Results
Twenty‐seven studies with a total of 4386 patients were included in the meta‐analysis. The summary sensitivity of transient elastography for staging fibrosis F ≥ 2, F ≥ 3 and F = 4 was 0.806 (95% CI, 0.756–0.847), 0.819 (95% CI, 0.748–0.874) and 0.863 (95% CI, 0.818–0.898), respectively, and the summary specificity was 0.824 (95% CI, 0.761–0.873), 0.866 (95% CI, 0.824–0.899) and 0.875 (95% CI, 0.840–0.903), respectively. The corresponding area under the summary receiver operating characteristic curve was 0.88 (95% CI, 0.85–0.91), 0.91 (95% CI, 0.88–0.93) and 0.93 (95% CI, 0.91–0.95), respectively. Meta‐regression showed that patient age contributed to heterogeneity.
Conclusions
Transient elastography performs well to diagnose liver fibrosis in patients with chronic hepatitis B, which may reduce the use of liver biopsy.
The austenite formation from lamellar pearlite was studied in a near-eutectoid Fe-0.6mass%C-2mass%Mn alloy with focus on the transition between partitioned and non-partitioned growth of austenite. ...The austenite was nucleated at pearlite colony boundaries and grew along the lamellae of pearlite. The isothermal austenite transformation curves revealed that the transition from slow to fast growth of austenite occurred over a narrow temperature range (720–725 °C). The ghost pearlite which had formed above the transition temperature transformed to a very fine mixture of martensite (previously pearlitic ferrite) and austenite (pearlitic cementite) upon cooling to room temperature. According to thermodynamic analysis which takes into account carbon transport from θ/α and θ/γ interfaces toward γ/α interfaces the transition temperature appears to be closer to experiment and significantly (ca. 20 °C) lower than that previously proposed assuming that the austenite was nucleated at the θ/α interface. Phase field simulation of the carbon and Mn distributions around the tip of a cementite lamella also seems to indicate the change of diffusivity which plays a leading role in the growth of austenite.
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The Community Land Model version 3 (CLM3) is the land component of the Community Climate System Model (CCSM). CLM3 has energy and water biases resulting from deficiencies in some of its canopy and ...soil parameterizations related to hydrological processes. Recent research by the community that utilizes CLM3 and the family of CCSM models has indicated several promising approaches to alleviating these biases. This paper describes the implementation of a selected set of these parameterizations and their effects on the simulated hydrological cycle. The modifications consist of surface data sets based on Moderate Resolution Imaging Spectroradiometer products, new parameterizations for canopy integration, canopy interception, frozen soil, soil water availability, and soil evaporation, a TOPMODEL‐based model for surface and subsurface runoff, a groundwater model for determining water table depth, and the introduction of a factor to simulate nitrogen limitation on plant productivity. The results from a set of offline simulations were compared with observed data for runoff, river discharge, soil moisture, and total water storage to assess the performance of the new model (referred to as CLM3.5). CLM3.5 exhibits significant improvements in its partitioning of global evapotranspiration (ET) which result in wetter soils, less plant water stress, increased transpiration and photosynthesis, and an improved annual cycle of total water storage. Phase and amplitude of the runoff annual cycle is generally improved. Dramatic improvements in vegetation biogeography result when CLM3.5 is coupled to a dynamic global vegetation model. Lower than observed soil moisture variability in the rooting zone is noted as a remaining deficiency.
In order to realize the real-time detection of abnormal green pellet particle size. First, image data of large-granularity green balls at different disk pelletizing machine material disk speeds and ...different camera angles are collected on site; then LabelImg software is used to label the image data of large-granularity green balls; and finally based on the YOLOv3 algorithm under the Pytorch deep learning framework train and detect large-grained ball image data. The experimental results show that: under the condition of high rotation speed of the material disk of the disc pelletizing machine, the detection accuracy can reach more than 90,58 % for the image data of a single large-grained green ball, and the comprehensive detection rate can reach more than 85 %.
This experiment investigated the effects of different dietary starch sources on the growth and glucose metabolism of geese. A total of 240 healthy 35-day-old male geese were selected and randomly ...divided into 4 groups, with 6 replicates per group and 10 geese per replicate. Four types of diets were prepared, with glutinous rice (rapidly-digestible starch), corn, indica rice and high amylose as their starch sources, and fed for 28 d. Results showed that after consuming different feeds, the blood glucose of geese first increased and then decreased, reaching its maximum value 0.5 h after feeding, and there were significant differences between the groups (P < 0.05). The body weight of the corn and indica rice group geese at 63 d was higher than that of the high amylose group (P < 0.05). The serum total cholesterol (TCHO) content in the glutinous rice and corn groups was higher than in the high amylose group (P < 0.05). The serum insulin content in the glutinous rice group was lower than in the corn and high amylose groups (P < 0.05), while the glucagon content was higher (P < 0.05). The α-amylase activities of the pancreas, jejunal chyme, and jejunal mucosa in the glutinous rice group were higher than in the indica rice and high amylose groups (P < 0.05). The liver glycogen content in the glutinous rice group was higher than the other groups (P < 0.05). The liver glucose-6-phosphate dehydrogenase (G-6-PD) content in the glutinous rice group was higher than the high amylose group's (P < 0.05), but the glycogen synthase kinase-3 β (GSK-3β) content was lower (P < 0.05). In conclusion, the corn and indica rice diets had a positive effect on the growth performance of the geese, while the high amylose diet had a negative effect. The glutinous rice diet leads to rapid release of glucose, strengthening glucose metabolism pathways such as glycogen synthesis and the pentose phosphate pathway, and further influencing lipid metabolism.
The Community Land Model version 3 (CLM3.0) simulates land‐atmosphere exchanges in response to climatic forcings. CLM3.0 has known biases in the surface energy partitioning as a result of ...deficiencies in its hydrological and biophysical parameterizations. Such models, however, need to be robust for multidecadal global climate simulations. FLUXNET now provides an extensive data source of carbon, water and energy exchanges for investigating land processes, and it encompasses a global range of ecosystem‐climate interactions. Data from 15 FLUXNET sites are used to identify and improve model deficiencies. Including a prognostic aquifer, a bare soil evaporation resistance formulation and numerous other changes in the model result in a significantly improved soil hydrology and energy partitioning. Terrestrial water storage increased by up to 300 mm in warm climates and decreased in cold climates. Nitrogen control of photosynthesis is revealed as another missing process in the model. These improvements increase the correlation coefficient of hourly and monthly latent heat fluxes from a range of 0.5–0.6 to the range of 0.7–0.9. RMSE of the simulated sensible heat fluxes decrease by 20–50%. Primary production is overestimated during the wet season in mediterranean and tropical ecosystems. This might be related to missing carbon‐nitrogen dynamics as well as to site‐specific parameters. The new model (CLM3.5) with an improved terrestrial water cycle should lead to more realistic land‐atmosphere exchanges in coupled simulations. FLUXNET is found to be a valuable tool to develop and validate land surface models prior to their application in computationally expensive global simulations.
Hydrological simulations play an important role in estimating terrestrial water budgets and monitoring extreme events such as floods. This study investigates how these simulations are affected by ...soil‐type datasets and characterizes how these effects vary with climate. We study the differences between two ensemble simulations in China with the Noah‐MP land surface model using two soil datasets from the Food and Agriculture Organization and Beijing Normal University. The differences in ensemble means are analyzed over a 10 year period from 2003 to 2012 with respect to estimated soil moisture, the partition of precipitation between evapotranspiration and runoff, and a flood magnitude index. Results show that the hydrological simulations using sandier soil types result in lower soil moisture, lower evapotranspiration, and higher subsurface runoff. Each of these effects varies uniquely with aridity. The changes in soil moisture decrease with increasing aridity, while the changes in water balance components (evapotranspiration and runoff) peak in the transitional zone between humid and arid regions. The flood magnitude, expressed as the maximum daily flow normalized by annual flow, is also substantially influenced by the input soil type. Soil types with more clay and less sand content yield significantly bigger floods, especially in arid regions.
Key Points
The sensitivity of soil moisture and surface water balance to soil type depends on aridity
Modeled soil moisture, evapotranspiration, and flood index are most sensitive in humid, transitional, and arid regions, respectively
Models with a groundwater component show greater sensitivities to soil type than those without a groundwater component
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