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Metaplastic changes in the renal pelvis are infrequent and may be malignant transformations to adenocarcinoma. The current study reports a case of intestinal metaplasia in the right renal pelvis, which was associated with staghorn calculi, in a 56-year-old female. The patient underwent a percutaneous nephrolithotomy. Immunohistochemical assessment of the mucosa of the renal pelvis revealed the positive expression of carcinoembryonic antigen, cytokeratin (CK)-7 and CK20, but negative expression for CK5/6 and vimentin. Furthermore, Ki67 expression was diffusely positive, while p53 was negative. Unlike other previously reported cases, the patient opted for active surveillance as opposed to radical nephrectomy, following the removal of the calculi. No evidence of progression was observed after three years of follow-up. Therefore, etiological treatment and close follow-up may be a suitable treatment option for localized intestinal metaplasia. [ABSTRACT FROM AUTHOR]

In this study, combustion and emissions characteristics of a turbocharged compression ignition engine fueled with dimethyl ether (DME) and biodiesel blends are experimentally investigated. The effects of nozzle parameter on combustion and emissions are evaluated. The result shows that with the increase of DME proportion, ignition delay, the peak in-cylinder pressure, peak heat-release rate, peak in-cylinder temperature decrease, and their phases retard. Compared to the nozzle 6 ? 0.40 mm, the peak cylinder pressure and peak heat-release rate are higher with nozzle 6 ? 0.35 mm, and their phases are advanced. Increased DME proportion in fuel blends causes greater differences. Compared to biodiesel, NOx emissions of blends significantly decrease; HC emissions and CO emissions increase slightly. DME-biodiesel blends can be used as an alternative in a turbocharged CI engine. To obtain low NOx emissions and a soft engine operation, for high DME proportion blended fuels, nozzle of 6 ? 0.40 mm adopted. [ABSTRACT FROM AUTHOR]

Jasmonate (JA) and ethylene (ET) are two major plant hormones that synergistically regulate plant development and tolerance to necrotrophic fungi. Both JA and ET induce the expression of several pathogenesis-related genes, while blocking either signaling pathway abolishes the induction of these genes by JA and ET alone or in combination. However, the molecular basis of JA/ET coaction and signaling interdependency is largely unknown. Here, we report that two Arabidopsis ET-stabilized transcription factors (EIN3 and EIL1) integrate ET and JA signaling in the regulation of gene expression, root development, and necrotrophic pathogen defense. Further studies reveal that JA enhances the transcriptional activity of EIN3/EIL1 by removal of JA-Zim domain (JAZ) proteins, which physically interact with and repress EIN3/EIL1. In addition, we find that JAZ proteins recruit an RPD3-type histone deacetylase (HDA6) as a corepressor that modulates histone acetylation, represses EIN3/EIL1-dependent transcription, and inhibits JA signaling. Our studies identify EIN3/EIL1 as a key integration node whose activation requires both JA and ET signaling, and illustrate transcriptional derepression as a common mechanism to integrate diverse signaling pathways in the regulation of plant development and defense. [ABSTRACT FROM AUTHOR]

Degradation and drug release behavior of thermogelling hydrogel of poly(ℇ-caprolactone-co-glycolide)-poly(ethylene glycol)-poly(ℇ-caprolactone-co-glycolide) [P(CL-GL)-PEG-P(CL-GL) (1880-1540-1880)] triblock copolymer were investigated. The copolymer aqueous solution (25 wt%) underwent sol-gel transition at 35°C as the temperature increased and formed a stable gel at body temperature. After incubation in PBS buffer solution (0.1 M) at 37°C, the gel degraded completely into a viscous liquid at 14th week. Chemical microstructural analysis of the degraded samples by 1H-NMR revealed the degradation occurring mainly on the glycolyl sequences of the copolymer. The pH value of the gel buffer solution maintained neutral during the initial 8 weeks, which may be beneficial for the preservation of activity of pH-sensitive drugs. Incorporation of drugs into the gel was formulated at room temperature without the use of any organic solvent. The gel formed a controlled release depot with delivery times of 12, 32, and 25 days for isoniazid, rifampicin and bovine serum albumin, respectively. Controlled release of hydrophobic rifampicin was achieved with insignificant burst effect due to the distribution of the drug mainly in the hydrophobic polyester regions of the gel. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:2603–2610, 2009 [ABSTRACT FROM AUTHOR]

The purpose of the present work was to upgrade the functionality and applicability of acrylonitrile-butadiene-styrene copolymer (ABS)/polycarbonate (PC) alloys by means of a simple blending technique. A fragrant ABS/ PC alloy was prepared by adding a fragrance to the ABS/PC matrix. By tests of volatility, mechanical properties, and processing fluidity and by SEM measurements it was found that the essence not only endowed ABS/PC alloy with fragrance but also acted as a lubricant and surface treatment agent during processing. With increasing fragrant masterbatch content, the impact strength and rate of elongation at break decreased and the processing properties improved, while the yield strength remained almost unchanged. The dosage of fragrant masterbatch needed to be kept under 5 phr (parts per hundred parts resin by weight) to obtain the best combination of properties of the fragrant ABS/PC alloy. In addition, the volatility of the essence was greatly affected by the nature of the essence, the ambient temperature, and the polymer matrix. The experimental results show that the fragrance of the ABS/PC alloy can be maintained for a long time at room temperature. [ABSTRACT FROM AUTHOR]

High-carbon high-speed steels (HSS) are very abrasion-resistant materials primarily due to their high hardness MC-type carbide and high hardness martensitic matrix. The effects of quenching and tempering treatment on the microstructure, mechanical properties, and abrasion resistance of centrifugal casting high-carbon HSS roll were studied. Different microstructures and mechanical properties were obtained after the quenching and tempering temperatures of HSS roll were changed. With air-cooling and sodium silicate solution cooling, when the austenitizing temperature reaches 1273 K, the metallic matrix all transforms into the martensite. Afterwards, the eutectic carbides dissolve into the metallic matrix and their continuous network distribution changes into the broken network. The second hardening temperature of high-carbon HSS roll is around 793 K. No significant changes in tensile strength and elongation percentage are observed unless the tempering temperature is beyond 753 K. The tensile strength increases obviously and the elongation percentage decreases slightly beyond 753 K. However, the tensile strength decreases and the elongation percentage increases when the tempering temperature exceeds 813 K. When the tempering temperature excels 773 K, the impact toughness has a slight decrease. Tempering at 793-813 K, high-carbon HSS roll presents excellent abrasion resistance. [ABSTRACT FROM AUTHOR]

Thermogelling poly(ɛ‐caprolactone‐co‐D,L‐lactide)–poly(ethylene glycol)–poly(ɛ‐caprolactone‐co‐D,L‐lactide) and poly(ɛ‐caprolactone‐co‐L‐lactide)–poly(ethylene glycol)–poly(ɛ‐caprolactone‐co‐L‐lactide) triblock copolymers were synthesized through the ring‐opening polymerization of ɛ‐caprolactone and D,L‐lactide or L‐lactide in the presence of poly(ethylene glycol). The polymerization reaction was carried out in 1,3,5‐trimethylbenzene with Sn(Oct)2 as the catalyst at various temperatures, and the yields were about 96%. The molecular weights and polydispersities (Mw/Mn) by gel permeation chromatography were in the ranges of 5140–6750 and 1.35–1.45, respectively. The differential scanning calorimetry results showed that the melting temperatures of the poly(ɛ‐caprolactone) components were between 30 and 40 °C. By the subtle tuning of the chemical compositions and microstructures of these triblock copolymers, the aqueous solutions underwent sol–gel transitions as the temperature increased, with the suitable lower critical solution temperature in the range of 17–28 °C at different concentrations. Transesterification in the polymerization process generated the redistribution of sequences, which remarkably affected the sol–gel transition temperature. The amphiphilic copolymers formed micelles in aqueous solutions with a diameter of 62 nm and a critical micelle concentration of about 0.032 wt % at 20 °C. Micelles aggregated as the temperature increased, leading to gel formation. The sol–gel transition was studied, with a focus on the structure–property relationship. It is expected to have potential applications in drug delivery and tissue engineering. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4091–4099, 2007 [ABSTRACT FROM AUTHOR]

Accurately determining the solubility of ethane in oil‐based mud is crucial for assessing the severity of gas kicks and implementing appropriate well control procedures. The key factors influencing the solubility of ethane gas in oil‐based drilling fluids include the content of base oil, pressure, temperature, and the viscosity of the drilling fluid. This study aims to test the solubility of high‐purity ethane in oil‐based mud under simulated downhole conditions in a 5000 m deep well. The test covers a temperature range of 40–140°C and a partial pressure range of 0.17–5.92 MPa. The effects of temperature, pressure, base oil content, and drilling fluid viscosity on the solubility of ethane are analyzed using various experimental data processing methods. The results show that the variation in ethane solubility with pressure and temperature is nearly linear within the specified ranges. Furthermore, the impact of pressure (1.24–2.78%/MPa) on solubility is approximately 50 times greater than that of temperature (−0.013 to −0.049%/°C) in oil‐based drilling mud. Additionally, ethane's solubility decreases as the drilling fluid's viscosity increases. The ethane solubility in 80% and 90% oil‐based muds is roughly 1.6 times and 2.0 times higher than in 70% oil‐based mud under the same testing conditions. Models for predicting ethane solubility have been developed using screening procedures and statistical regression. These models can be incorporated into gas–liquid flow models to analyze flow behavior during gas kicks. [ABSTRACT FROM AUTHOR]

The potential application of the hybrid phosphorene/graphene (P/G) composites as an anode material in Na-ion batteries (NIBs) has been explored based on first-principles calculations. The calculated elastic constants reveal that the P/G has an ultrahigh stiffness, which can effectively suppress the undesirable structural deformation during the sodiation and desodiation cycles. Na atoms can strongly bind with the phosphorene single-layer (SP), double-layer (DP), and their composites with graphene (SP/G, DP/G, G/DP/G), and can even cause a sliding between the layers when the DP/G accommodate more Na atoms. The migration of Na in P/G is anisotropic with the minimum energy path along the zigzag channel. The low diffusion barriers of only about several tens of meV ensure the high mobility of Na within the layers, and thus lead to rapid charge/discharge capacity of P/G. The electronic structures show that the hybrid P/G becomes metallic with the Na incorporation, which contributes to the good electric conductivity in P/G. We further demonstrate that the average open circuit voltage (OCV) of DP/G is 0.53 V, which is comparable to other anode materials. These results suggest that P/G composites hold great potential to be a good anode material in NIBs. [ABSTRACT FROM AUTHOR]

Domestic and foreign relevant literatures of granular column collapse movement models are concluded to analyze the effects of initial spatial characteristics, essential physical properties of particles, boundaries, and environment conditions of model on the movement and accumulation characteristics of granular columns. Besides, the related mechanisms of movement and accumulation characteristics of granular columns are also analyzed. Remarkable linear and power relationships exist between the movement distance and the aspect ratios of initial height to initial width. Similarly, remarkable linear and power relationships exist between accumulation height and aspect ratio of initial height to initial width. The movement patterns and energy consumption mechanisms for granular columns with large aspect ratios are significantly different from those with small aspect ratios. A consensus has basically been reached concerning the effect of particle size, particle stiffness, particle breakage, and wet particles on the movement and accumulation characteristics of granular columns. Some preliminary research achievements of the effects of different wall constraints, fluidization phenomenon due to the gas mixing and water condition on the movement and accumulation characteristics of granular column are obtained. However, there still exist disagreements in the conclusions about the influences of initial porosity of granular column, particle friction, and wall friction on the movement and accumulation characteristics of granular column. A review of the current research indicate that the research in the future will be focused on the relationship between forces acted on particles and movement regimes. The mechanisms of the effect of complex particle shape, surface, particle density, and water movement conditions on the movement and accumulation characteristics of granular column collapse will also be focused on in the future.

Dissolved oxygen (DO) is vital to aquaculture industry and affects the yield of aquaculture. Low DO in water can lead to death of crabs, therefore, it is important to measure DO accurately. However, the DO sensors are usually expensive and often lost function due to corrosion in water environmental and adsorption of different materials on their surface, which result in the inaccuracy in measured DO values. It is thus important to develop effective methods to estimate DO concentrations by using other environmental variables, which may reduce farmers' cost because DO sensors are not used. In this research, the collected environmental data, including temperature, pH, ammonia nitrogen, turbidity, were used to estimate DO concentrations in crab ponds. The data were preprocessed to eliminate missing values and outlier. Correlation analysis was applied to determine the relationship between environmental variables (temperature, pH, ammonia nitrogen, turbidity) and DO to show the rationale of using these four variables to forecast DO concentration. Principal component analysis was used to reduce the dimension of environmental data to reduce computation cost. For DO concentration estimation, it is more important to make the estimation of DO concentration at low values more accurate because DO concentration at low values is dangerous to crabs. This implies that estimation of DO concentrations at low or high values should be treated differently and applied different rates. Based on the Long Short-Term Memory (LSTM), a low DO concentration estimation model of Low Dissolved Oxygen Long Short-Term Memory(LDO-LSTM), which can improve the estimation accuracy of low DO values was proposed by optimizing the loss function of LSTM back propagation. The loss function of LDO-LSTM was based on the Mean Absolute Percentage Error (MAPE). According to the trend of DO, the true DO and the estimated DO values were applied weight functions. The Root Mean Square Error (RMSE) and the MAPE were used to evaluate the performance of LDO-LSTM and LSTM in DO estimation. Experimental results show that the value of RMSE and MAPE were stable at about 0.1 for LSTM and LDO-LSTM in forecasting DO when dissolved oxygen was higher than 6mg/L and the value of RMSE and MAPE of LDO-LSTM were lower than LSTM by 0.25 and 0.139. The results prove that the proposed method can not only provide desirable estimation accuracy for DO concentrations at high values but also make the estimated DO concentrations at low values more accurate. This research is expected very useful in reducing aquaculture costs and improving accuracy in forecasting DO especially at low values.