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In order to explore the reservoir characteristics of shallow shale gas reservoir in Zhaotong and its differences with other shale gas blocks in Sichuan Basin, the pore structure of Zhaotong shale gas reservoir was comprehensively studied by various means, including X -ray diffraction, gas adsorption (CO2, N2), NMR, and field emission-scanning electron microscopy. In addition, the adsorption capacity of samples in this area was measured by volume method and the main controlling factors were analyzed. The results show that the shale reservoir in the Zhaotong demonstration area is dominated by clay and quartz minerals, with an average content of 23.1% and 34.3%, respectively. Pore-size distribution is concentrated in the range of 0.5–1000 nm, with micropore and mesopore as the main body. Scanning electron microscopy shows that the reservoir space types are mainly organic pores, intergranular pores, intragranular pores, and microfractures. Among them, organic pores are the most developed and most of them appear in large area network structures with good connectivity. The results of the methane isothermal adsorption test show that the adsorption capacity of shale in the Zhaotong area is positively correlated with TOC content, specific surface area, and micropore volume ( D ≤ 10 nm), but poorly correlated with total pore volume. Due to the influence of mineral types and genesis, the adsorption capacity of shale in this area is negatively correlated with clay content and poorly correlated with quartz content. Through data comparison and analysis, the adsorption capacity of shale in the Zhaotong area is higher than that in the Fuling and Changning–Weiyuan areas. Additionally, due to the influence of mineral genesis, the changing trend of shale adsorption capacity with quartz content is also different in different regions. [ABSTRACT FROM AUTHOR]

Background: The Renal Activity Index for Lupus (RAIL) consists of urine protein assessment of neutrophil gelatinase–associated lipocalin, kidney injury molecule-1, monocyte chemotactic protein 1, adiponectin, hemopexin, and ceruloplasmin, which non-invasively identifies lupus nephritis (LN). We aimed to delineate RAIL scores with inactive versus active LN and changes over time with response to LN induction therapy. Methods: There were 128 pediatric patients with systemic lupus erythematosus (SLE) and age-matched healthy controls recruited in a prospective case control study, with kidney biopsy confirmation of LN. Laboratory and clinical information was recorded and urine collected at diagnosis and end of induction and during maintenance therapy. Response to therapy was assessed by repeat kidney biopsy or laboratory parameters. Urine was assayed for RAIL biomarkers and the RAIL score calculated. Results: Pediatric RAIL (pRAIL) scores from 128 children and young adults with SLE (with/without LN: 70/38) including 25 during LN induction therapy, differentiated clinically active LN from inactive LN or without LN, and controls (all p < 0.0017). pRAIL scores significantly decreased with complete LN remission by 1.07 ± 1.7 (p = 0.03). Conclusions: The RAIL biomarkers differentiate LN patients based on activity of kidney disease, with decreases of ≥ 1 in pRAIL scores indicating complete response to induction therapy. Significantly lower RAIL scores in healthy controls and in SLE patients without known LN raise the possibility of subclinical kidney disease. [ABSTRACT FROM AUTHOR]

Wallpapers as the main decoration materials employed in the high-rise and civil buildings will cause fire when exposed to high temperature or high excessive current, which result in the loss of property and injuries. In order to reduce the fire risk caused by wallpapers, it is necessary to develop the study of wallpaper combustion behavior under different fluxes from 20 to 50 kWm−2 with 10 increments by fire propagation apparatus. In this study, three types of wallpapers (flame-retardant, water-proof and common) are investigated to deepen our understanding of vertical combustion behavior to reduce the fire risk of building caused by wallpaper fire. The visual observation, heat release rate, mass loss, ignition time, CO and CO2 yields, and TOC during the whole combustion process were analyzed to deepen the knowledge of combustion behaviors for different kinds of wallpapers. Flame-retardant and water-proof wallpapers will crack or bubble during the burning process. Under lower external heat flux, wallpapers will form charring layers during the burning process, while at high external heat fluxes, the formed charring layers will reduce to make combustion intensity fiercer. The formed charring layer will appear after burning for 10 to 20 s to inhibit the heat from the radiation and convection of the environment into sample to decrease combustion intensity. The transformed ignition time is linear with external heat flux, and the transformed index is equal to 1, which is consistent with thermal thin material. The CO2 yield of flame-retardant and common wallpapers is similar to CO yield except water-proof wallpaper, and with the fluxes increase, the gas yield of water-proof wallpaper increases first, then decreases and finally increases. The results and experimental data in this study can provide guidance for the fire protection department to assess the fire risk of wallpapers and ensure the safety of people in the buildings. [ABSTRACT FROM AUTHOR]

Multi-scale experiments including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), fire propagation analysis (FPA), and fire resistance test were carried out to study thermal insulation of glass fiber. Temperature range of pyrolysis and combustion, heat of reaction and mass loss were measured by TGA and DSC. The percentage of mass loss measured by TGA and FPA is almost the same. The melting of glass fiber lead to the morphological changes of glass fiber under high radiation heat flux in FPA. The fire resistance test shows that glass fiber has excellent thermal insulation in two structures at low temperatures, but the melting of glass fiber has become a deadly destruction to structural failure at high temperatures. Simulation has been done to the fire resistance of a typical high-speed floor structure containing glass fiber. The simulation results are in good agreement with the experimental results, revealing the importance of considering pyrolysis and melting of glass fiber in predicting its thermal insulation behavior. [ABSTRACT FROM AUTHOR]

The thermal degradation behaviors of commercial flame-retardant unsaturated polyester glass fiber-reinforced plastic (polyester GFRP) containing aluminum trihydrate (ATH) were studied using thermogravimetric analysis and a combination of TG-Fourier transform infrared-gas chromatography/mass spectrometry (TG-FTIR-GC/MS). From the variation of derivative thermogravimetry curves, it is found that the degradation of polyester GFRP can be divided into two stages with the critical conversion rate of 0.35. Activation energies were calculated by Starink method, and then the kinetic triplet was further determined by Coats-Redfern method. The results show that the dehydration of ATH and breakage of ester linkages lead to the first major mass loss, and volatile products including H2O, dicyclopentadiene, benzaldehyde and dimethyl phthalate are generated. Consecutive reaction occurs in the second stage. The statistical rupture of polyester and polystyrene chains leads to the formation of toxic volatiles, especially styrene, α-methylstyrene, toluene, ethylbenzene, benzaldehyde, phenol and phthalic anhydride. Possible reaction mechanisms are discussed in order to explain the observed results. The experimental results could give guidance to the fire safety design of high-speed train and provide basic data for numerical simulation of fire accidents. [ABSTRACT FROM AUTHOR]

This paper studies the stability problem of linear systems with two additive time-varying delays. Firstly, a modified Lyapunov-Krasovskii functional (LKF) is constructed involving the delay-dependent non-integral items and some augmented single-integral items. Secondly, based on the improved LKF, a stability criterion is derived via the generalized free-matrix-based inequality application, which is less conservative than some recent existing ones. Thirdly, a generalized refinement of allowable delay set removed some impossible delay subsets is proposed to further reduce the conservatism of the stability criterion. Finally, a numerical example and an application of the load frequency control for a single area power system are presented to show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This study investigated the effects of loadings of cellulose nanofibers extracted from jute fibers on the tensile property, onset temperature, melting temperature, crystallization temperature, and thermal stability of polyvinyl alcohol matrix. The synthesized nanocomposites were characterized by scanning electron microscopy, Fourier transform infrared spectrometry, tensile tests, dynamic mechanical analysis, differential scanning calorimetry, and thermogravimetric analysis. Experimental results showed that there is an increase in both the modulus and strength of the composite films up to 10% cellulose nanofibers loading and a gradual decrease with further increases to 30% cellulose nanofibers loading. In addition, the thermal degradation of the composites occurs at higher temperature than that of both cellulose nanofibers and neat polyvinyl alcohol. However, thermal stability of the composites decreases with increase of the cellulose nanofibers content higher than 20 wt %. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to examine patterns of initial prescriptions, investigate time to initiation of biologic disease-modifying anti-rheumatic drugs (bDMARDs), and evaluate the impact of clinical and other baseline factors associated with the time to first bDMARD in treating children with newly diagnosed non-systemic juvenile idiopathic arthritis (JIA). Methods: Using longitudinal patient-level data extracted from electronic medical records (EMR) in a large Midwestern pediatric hospital from 2009 to 2018, the initial prescriptions and prescribing patterns of bDMARDs, conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs), non-steroidal anti-inflammatory drugs (NSAIDs) and glucocorticoids within 3 months of JIA diagnosis were examined. Kaplan-Meier analyses were performed to assess time to initiation of bDMARDs. Cox proportional hazard models were used to identify factors associated with time to first bDMARD. Results: Of 821 children, the proportion of patients with initial csDMARDs increased from 45.3% in 2009 to 60.3% in 2018. Around 57.5% of polyarthritis rheumatoid factor-positive (Poly RF+) patients and 43.2% of polyarthritis rheumatoid factor-negative (Poly RF−) patients received a bDMARD therapy within 3 months of diagnosis, 14.4% as monotherapy and 28.3% in combination with a csDMARD. Among patients who received combination therapy, combination of methotrexate with adalimumab increased from 16.7% in 2009 to 40% in 2018. The proportion of patients treated with adalimumab gradually increased and passed etanercept in 2016. The predictors of earlier initiation of biologic therapy were JIA category enthesitis-related arthritis (ERA) [hazard ratio (HR) vs persistent oligoarthritis 4.82; p < 0.0001], psoriatic arthritis (PsA) (HR 2.46; p = 0.0002), or Poly RF− (HR 2.43; p = 0.0002); the number of joints with limited range of motion (HR 1.02; p = 0.0222), and erythrocyte sedimentation rate (ESR, HR 1.01; p = 0.0033). Conclusions: There was a substantial increase in the proportion of patients receiving the combination of methotrexate and adalimumab among patients receiving combination therapy. Adalimumab overtook etanercept as the most frequently prescribed bDMARD. Multiple factors affect the time to biologic initiation, including the number of joints with limited range of motion, ESR, and JIA category. [ABSTRACT FROM AUTHOR]

Besides combustion behavior under normal atmosphere, combustion behavior under special environment is also an important aspect for safety operation of China high-speed train. The commercial flame-retardant natural rubber employed in China high-speed train as the main floor cloth material was investigated in this study at low oxygen atmosphere with 18 kW m−2 to 60 kW m−2 external heat fluxes by means of ASTM E2058 fire propagation apparatus to deepen the knowledge of combustion behavior. The ignition time of sample mainly depended on external heat flux not the oxygen concentration (only low and normal oxygen concentration) except 40 kW m−2. During the whole combustion process two main stages appeared, one was thermal decomposition of sample, and the other stage was the forming charry layer combustion. The CO and CO2 yields decreased with external heat flux increasing and the ratio of yCO/yCO2 firstly increased and then decreased. The experimental data in this study can provide guidance for fire safety design and assessment of China high-speed train. [ABSTRACT FROM AUTHOR]

Primary hepatic angiosarcoma (PHA) is a rare malignant tumor that occurs mainly in the elderly, with almost no specific symptoms or tumor markers. Information on the imaging characteristics of this tumor is limited due to its rarity. Therefore, it is difficult to diagnose PHA. So far, its definite diagnosis depends on histopathologic examination combined with immunohistochemical results. Patients with PHA have a poor prognosis in spite of surgical resection of this tumor. In this case report, we present a 72-year-old woman with PHA, focusing on the imaging features of this tumor, especially its enhancement pattern on contrast-enhanced ultrasound images. Contrast-enhanced ultrasound provided helpful information for diagnosis. [ABSTRACT FROM AUTHOR]

Epithelioid angiomyolipoma is considered to be a rare variant of angiomyolipoma and potentially malignant. Reported cases of renal epithelioid angiomyolipoma with extension into the renal vein and inferior vena cava are even rarer. Once it occurs, it is difficult to differentiate from renal cell carcinoma on imaging. In addition, very few of the reported cases presented contrast-enhanced ultrasound images. Here, we report a case of a renal epithelioid angiomyolipoma extending into the renal vein and inferior vena cava along with its contrast-enhanced ultrasonic information. Contrast-enhanced ultrasound provided valuable information for diagnosis in this case. [ABSTRACT FROM AUTHOR]

A correction to this paper has been published: https://doi.org/10.1007/s40272-021-00447-1 [ABSTRACT FROM AUTHOR]