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The presence of the large channel in fractured-vuggy reservoirs diminishes the sweep efficiency of any water, gas or polymer flooding. This paper presents a novel type of rubber particle for water shutoff agent and the flow direction of water is adjusted by plugging the large channel. Simultaneously, through the microscopic displacement experiment of the organic glass etching model, the water flow behavior and injection parameters optimization are studied. The results show that the resistance of solid media to fluid flow is almost zero when the oil-water two-phase flow occurs, and the gravity action is prominent. Therefore, there are still a lot of residual oil of karst cave, flow around oil and attic oil with poor connectivity after the fractured-vuggy reservoir is displaced by injected water. In addition, the rubber particles can form a temporary plugging zone by migration – accumulation – bridging under formation conditions, resulting in the flow direction of subsequent injection water changes from the large channel to the small channel, thereby reducing water content and increasing oil production. By optimizing the injection parameters of rubber particles, the optimal injection volume, particle size and injection speed are obtained, which are 0.02PV, 0–1 mm, 2–4 mm and 25 mL/min, respectively. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is one of the most common types of hematologic malignancy for which the underlying molecular mechanisms remain largely unclear. Dysregulated miRNA expression has been shown to be involved in MM tumorigenesis, progression and drug response. Therefore, a comprehensive analysis based on miRNA-level integrated strategy was performed. This study aimed to elucidate key miRNA signatures and pathways in MM by integrated bioinformatics analysis. Expression profiles GSE24371, GSE49261 and GSE54156 were obtained from the Gene Expression Omnibus database, and differentially expressed miRNAs (DEMirs) with p < 0.05 were identified. The target genes of these DEMirs were obtained from ENCORI database, and functional enrichment, subpathway enrichment and protein–protein interaction network construction were performed. The key target genes were identified by random walk algorithm and survival verification was performed. and discussion: First, six up-regulated and four down-regulated DEMirs shared between any two GSE data sets were identified. Second, target genes (DEMirTGs) by up-regulated and down-regulated DEMirs were obtained. Functional and subpathway enrichment analysis showed that these up-regulated DEMirs are consistently involved in the Wnt signaling pathway. Moreover, enrichment of the down-regulated DEMirs is mainly in the MAPK signaling pathway. Finally, a protein–protein interaction sub-network for these DEMirTGs was constructed, the correlations between the two key genes were identified and survival in MM was evaluated using multiple independent data sets. We identified miRNA signatures and key target genes that were closely related to MM biology, and these genes might serve as potential therapeutic targets for MM patients. [ABSTRACT FROM AUTHOR]

Upon aging, paper documents and books become progressively damaged. Paper deacidification is a fundamental conservation intervention. In this study, we report on the use of nanoparticles of titanium dioxide (TiO2) and magnesium hydroxide (Mg(OH)2) associated with hydroxyethylcellulose (HEC) to inhibit acidification, photo-induced degradation, and biodeterioration of paper. With the aid of ultrasound, Mg(OH)2 nanoparticles with a narrow size distribution can be obtained through homogeneous precipitation in water. Furthermore, to demonstrate the efficacy of the nanocomposite and the performance of treated and untreated paper, photo- and thermal-induced degradation is discussed. The results show that using the controlled double-jet precipitation (CDJP) it is possible to synthesize Mg(OH)2 particles with a narrow size distribution (18-87 nm). The nanocomposite of Mg(OH)2-TiO2-HEC increases the durability of paper by imparting fungal growth resistance (D= 34.6 mm), moderate alkalinity (pH = 8.4), mechanical reinforcement (from 817-896 N/m), and UV protection. Additionally, there is a slight color difference (ΔE* = 0.8) between the treated and untreated paper. Both photodegradation and thermal degradation indicate that the paper treated with this nanocomposite (Mg(OH)2-TiO-HEC) has increased stability. [ABSTRACT FROM AUTHOR]

This study studied the eyes of three anencephalic stillborns to evaluate whether brain degeneration affected eye development and/or survival. The study encompassed histology, scanning electronmicroscopy, and immunocytochemistry. The corneae were otherwise normal except for the presence of blood vessels in the stroma and the posterior surface of the cornea demonstrated wrinkles. Synaechia was present and the lens had occasional vacuolated cells. The retinae had normal layers in most regions except the center where fibroblasts infiltration was observed. The optic nerve was atypical and composed of aggregates of disoriented fibroblasts and disoriented nerve fibers. Anti-cleaved caspase 3 immunocytochemistry revealed only few positive dying cells in the visual cell layer. Antineurofilament 200 reactions demonstrated positive ganglion cells even in the anencephalic eyes. The choroids in anencephaly had more VEGF positive sites, indicating vascularization in both control and anencephalic eyes. If the brains degenerate before retinal maturation, then such degenerations may not have an effect on subsequent retinal development except for the degeneration of the nerve fiber layer. If the brains degenerate after retinal maturation, then the survival of the retinae does not appear to rely on its linkage with the brain at birth, again apart from the degeneration of nerve fibers. [ABSTRACT FROM AUTHOR]

This study describes the pathological changes in 20 heroin addicts (12 male and 8 female) autopsied 24 h after sudden death. The central nervous system (including the pituitary body) and the adrenal medulla were studied, along with those from age-matched controls who died from traffic accidents. Immunohistochemistry and histological (Hematoxylin and eosin) observation were performed. Some neuronal cells in every region of the CNS were positive for opioid receptors but these cells were most numerous in the hippocampus. Positive opioid fibers were most abundant in the basal ganglia region. Histopathology indicated coagulative changes of cytoplasm and dissolution of Nissl bodies of neuron. Edema of nerve fibers was frequently demonstrated. Pituitary body showed an evident decrease or even absence of basophils in the pars anterior. The adrenal medulla featured a down regulation of chromaffin granules. Degeneration of CNS neurons and fibers, alterations in hormonal and blood pressure regulation therefore would be the prime targets of heroin addiction in human subjects. [ABSTRACT FROM AUTHOR]

A novel semidiscrete Peierls-Nabarro model is introduced which can be used to study dislocation spreading at more than one slip plane, such as dislocation cross-slip and junctions. Within this essentially continuum model, the nonlinearity which arises from the atomic interaction across the slip plane is dealt with atomistic and/or ab initio calculations. As an example, we study the dislocation cross-slip and the constriction process in two contrasting fcc metals, Al and Ag. We find that the screw dislocation in Al can cross-slip spontaneously in contrast with the screw dislocation in Ag, which splits into two partials, and thus cannot cross-slip without first being constricted. The response of the dislocations to an external stress is examined in detail. The dislocation constriction energy and the critical stress for cross-slip are determined, and, from the latter, we estimate the cross-slip energy barrier for the straight screw dislocations. [ABSTRACT FROM AUTHOR]

We re-examine two important issues within the Peierls-Nabarro model, which are critical in obtaining accurate values for the Peierls stress. The first is related to the sampling scheme (double versus single counting) of the misfit energy across the glide plane and the second is the effect of atomic relaxation on the Peierls stress. We argue that the double-counting scheme is physically more appropriate. An analytical formula is derived for the Peierls stress of dislocations in alternating lattices. The atomic relaxation is shown to play an important role on the Peierls stress for narrow dislocations. [ABSTRACT FROM AUTHOR]

The poor interfacial properties of polyvinyl alcohol (PVA) fibers and epoxy resin seriously affect the toughening effect of PVA fibers on epoxy resin. To solve this problem, the surface of PVA fibers was modified with 3-aminopropyltriethoxysilane (KH550) and 3-glycidoxypropyltrimethoxysilane (KH560), as well as the surface of PVA fibers with tannic acid (TA) and KH560. The acid-cured epoxy resin toughening mechanism of the modified PVA fibers was systematically investigated by multiscale analysis. The experimental data showed that the epoxy resin performed best when TA and KH560 synergistically modified PVA fibers. The impact strength of the epoxy resin increased by 76.3% and the tensile strength by 20.3%. The toughening mechanism of modified PVA fibers on the epoxy resin was revealed by a series of characterizations such as Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA). Because KH560 can participate in the curing reaction of the epoxy resin, it greatly enhances the adhesion between the fiber and the resin. The toughening mechanism of TA and KH560 working together on PVA fibers to strengthen epoxy resin is summarized through the analysis of different scales. This also offers theoretical and experimental support for using PVA fibers in composites. [ABSTRACT FROM AUTHOR]

Hydrophilic coatings were prepared by dip-coating bare glass in polyvinylpyrrolidone (PVP)/silicon dioxide (SiO2) or polyvinylpyrrolidone (PVP)/carboxybetaine acrylamide (CBAA) suspensions. The effects of surface wettability on the anti-fogging and anti-icing properties of the two coatings were investigated. The surface morphologies of the coatings were characterized by polarized light microscopy and laser confocal microscopy, and the hydrophilicity of the coatings depended on the binding capacity of the hydrophilic functional groups in the fillers with water. The wettability of the coating surface was characterized by contact angle measurements, and it improved with increasing filler content. The coatings with the addition of more than 80 wt % of SiO2 or 1 wt % of CBAA showed superhydrophilic behavior. The anti-fogging and anti-frosting test results showed that the two coatings successfully prevented the development of fog and frost. The anti-icing properties of the coatings were also characterized. At three different temperatures, the anti-icing performance of the CBAA coating was better than that of the SiO2 coating. For, instance, at −15 °C, the icing delay time of PVP/SiO2 coating was 306.7 s and that of PVP/CBAA coating was 630.0s. Thus, the icing time of the CBAA coating was 323.3s longer than that of the SiO2 coating. When less than 80 wt% SiO2 or 10 wt% CBAA was added, the coating had good transparency. [ABSTRACT FROM AUTHOR]

The carbon fibres were used to enhance the materials by selected laser sintering. Gas phase oxidation, dense nitric acid and the coupling reagent processing together with dense nitric acid were adopted to modify carbon fibres, the microstructure of carbon fibres surface after treatment were analysed by SEM, and the strength of the composites was tested. The results demonstrate that the carbon fibre modified by 65-68% KHNO3 + 1% KH550 is considered as the optimal method. With the increase of carbon fibres content, the strength of the composite increases first and then decreases within a certain range. When the carbon fibres content at 3 wt-%, the green strength and the post-curing strength reached 0·87 and 9·614 MPa respectively, and the rate increased by 55·21 and 32·17% compared to the unreinforced. [ABSTRACT FROM AUTHOR]

The carbon fibres were used to enhance the materials by selected laser sintering. Gas phase oxidation, dense nitric acid and the coupling reagent processing together with dense nitric acid were adopted to modify carbon fibres, the microstructure of carbon fibres surface after treatment were analysed by SEM, and the strength of the composites was tested. The results demonstrate that the carbon fibre modified by 65-68% KHNO3 + 1% KH550 is considered as the optimal method. With the increase of carbon fibres content, the strength of the composite increases first and then decreases within a certain range. When the carbon fibres content at 3 wt-%, the green strength and the post-curing strength reached 0·87 and 9·614 MPa respectively, and the rate increased by 55·21 and 32·17% compared to the unreinforced. [ABSTRACT FROM AUTHOR]

Nowadays, medicines from plant sources play a vital role in healthcare management. Chrysin, a plant flavonoid, possesses a wide range of pharmacological activities. The aim of present investigation was to evaluate the safety of chrysin by determining toxicity after acute and sub-chronic oral administration in rats. Acute oral toxicity (AOT) and sub-chronic oral toxicity studies of chrysin were carried out according to OECD 425 and OCED 408 in Sprague Dawley rats. In AOT, oral administration of chrysin (5000 mg/kg) showed 40% mortality. In the sub-chronic toxicity study, daily oral administration of chrysin (1000 mg/kg) showed significantly decreased body weight whereas liver weight was increased significantly in male rats. A significant alteration in the hematology (RBC, MCH, MCHC, TLC, lymphocytes, and neutrophil) and blood chemistry (albumin, bilirubin, ALT, AST, creatinine, and GGT) were found in chrysin (1000 mg/kg) treated rats which were either limited to one sex or lacked dose-response or were within the normal laboratory ranges. There was a significant increase in hepatic and renal oxido-nitrosative stress in chrysin (1000 mg/kg) treated rats. There was no significant change in electrocardiographic (except heart rate), hemodynamic, the left ventricular function, and lung function test. Renal and hepatic histological aberrations were induced in chrysin (1000 mg/kg) treated rats. In conclusion results of the present investigation determined the LD50 value of chrysin to be 4350 mg/kg whereas NOAEL and LOAEL of chrysin was found to be 500 and 1000 mg/kg, respectively for both the sexes. [ABSTRACT FROM AUTHOR]

We have systematically studied dislocation cross-slip in Al at zero temperature by atomistic simulations, focusing on the dependence of the transition paths and energy barriers on dislocation length and position. We find that for a short dislocation segment, the cross-slip follows the uniform Fleischer (FL) mechanism. For a longer dislocation segment, we have identified two different cross-slip mechanisms depending on the initial and final positions of the dislocation. If the initial and final positions are symmetric relative to the intersection of the primary and cross-slip planes, the dislocation cross-slips via the Friedel–Escaig (FE) mechanism. However, when the initial and final positions are asymmetric, the dislocation cross-slips via a combination of the FL and FE mechanisms. The leading partial folds over to the cross-slip plane first, forming a stair-rod dislocation at the intersection with which the trailing partial then merges via the FL mechanism. Afterwards, constrictions appear asymmetrically and move away from each other to complete the cross-slip via the FE mechanism. [ABSTRACT FROM PUBLISHER]

Detection of silicon (Si) in a dilute acid extract (1 M HCl+2.3 M HF) by inductive coupled argon plasma (ICAP) procedures was equivalent to the traditional silicomolybdous blue (colorimetric) method (r=+0.99). The glassware, nebulizer, spray chamber, and torch assembly of the ICAP instrument consisted of HF resistant materials. Comparison of HCl–HF extraction with autoclave-induced digestion (AID) for selected leaf reference materials indicated good agreement for corn stalks and bluegrass clippings, but not for apple or peach leaves. Recovery of added Si to various leaf tissue prior to HCl–HF extraction was excellent, ranging from 96.5 to 103.3%. Recovery of Si added to a closed nutrient solution by muskmelon plants varied from 97 to 100%. The dilute HCl–HF extraction of Si from rapidly growing plant tissue and measurement by ICAP methodology provides a rapid procedure, minimal chemicals, and a low correction factor reducing potential errors. [ABSTRACT FROM AUTHOR]

Abstract. Office work is situated social action, a notion that includes both the social actions of computer systems in their interactions with office workers and other computer systems. This notion can be operationalized by dialogue context, which can then be used as a design parameter in office information systems. Observational data were collected by video recording a secretary's activities over an 8 hour duration. The data were analysed and discussed with the secretary to identify her action units. These action units were then related using an action graph. An interpretation of the action graph and observational data suggest certain features that a dialogue context management mechanism should have. They are: (1) a good match between applications and activities, (2) automated tools to support routine activities, and (3) informative and manageable metaphor to model the real world. [ABSTRACT FROM AUTHOR]

Purpose: Gait variability analysis has been clinically adopted to characterize the presentation of various neurological diseases. However, literature and practice lack a comprehensive murine model assessment of the gait deficits that result from transient focal ischemic stroke. Further, correlations between gait parameters and the gene expression profiles associated with brain ischemia have yet to be identified. This study quantitatively assesses gait deficits through a murine model of transient focal cerebral ischemia on day 7 to determine associations between gait deficits and ischemia-related gene expressions. Methods: A total of 182 dynamic and static gait parameters from the transient middle cerebral artery occlusion (MCAO) murine model for simulating human transient focal ischemic stroke on day 7 were measured using the CatWalk system. Pearson's correlation analysis and genes associated with ischemia were identified from the existing literature to aid the investigation of the relationship between gait variability and gene expression profiles. Results: Thirty-nine gait parameters and the mRNA expression levels of four of the eight ischemia-associated genes exhibited more significant change in the MCAO models (p < 0.005) on day 7. Twenty-six gait parameters exhibited strong correlations with four ischemia-associated genes. Conclusion: This examination of gait variability and the strong correlation to the gene expression profiles associated with transient focal brain ischemia on day 7 provides a quantitative and reliable assessment of the MCAO model's motor performance. This research provides valuable insights into the study of disease progression and offers novel therapeutic interventions in the murine modeling of ischemic stroke. [ABSTRACT FROM AUTHOR]

TF antigen binding lectins from dietary sources PNA, ACA, ABL, JAC, and SRL from Sclerotium rolfsii have been reported to induce diverse effects on cancer cell proliferation by different mechanisms. This study aimed to compare effects of these lectins on growth and cell cycle progression in colon cancer HT29 and SW620 cells. As reported SRL, ABL, and JAC inhibited while PNA and ACA increased cell proliferation. ABL and JAC treated HT29 cells showed increased cell population in G0/G1 phase. PNA, ACA, ABL, and JAC increased SW620 cell population in S and decreased in G2/M phase. In contrast, SRL and JAC increased hypodiploid population in both the cells. PNA and ACA reduced whereas SRL and ABL diminished cell cyclin D1 expression. SRL, PNA, and ACA also reduced cellular cyclin D3 level while SRL, ABL, and JAC reduced cyclin E levels. ABL decreased CDK5 levels while SRL and ACA completely abolished CDK5 expression. All the lectins completely abolished cyclin D2 expression. These results not only confirms growth regulatory effects of TF-binding lectins but also indicates different effects of these lectins on cell growth is associated with regulation on expression of cell cycle associated proteins in G1-S phase and on cell cycle progression. [ABSTRACT FROM AUTHOR]

Sediment cores collected at six freshwater discharge outlets of the Pearl River Estuary were analyzed for metal (Al, Fe, Cr, Pb, and Cd) concentration and risk assessment. The contents of Cr, Pb, Fe, and Al in these samples were measured by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), and Cd was measured by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The result showed that the concentration ranged (in mg/kg dry weight) as follows: Al, 7,880–97,700; Fe, 30,100–51,900; Cd, 0.23–1.09; Cr, 48.7–109; Pb, 22.3–70.2; respectively. The sediments of different particle size were measured and the result showed that the pelitic fraction (< 0.05 mm) was more enriched in heavy metals. Cd and Pb showed a similar spatial distribution in the sediment, which reflected similar anthropogenic origins. In addition, the temporal distribution of Cr, Pb, and Cd showed a light increase from the 1970s to the 2000s. Furthermore, the enrichment factor (EF) and the geo-accumulation index (Igeo) were used to comprehensively evaluate the pollution degree of heavy metals. The findings will be useful in proposing measures for strategic environmental control in estuaries. [ABSTRACT FROM AUTHOR]

In this work, we compared the cancer preventive activities of Polyphenon E (PPE), a standardized green tea polyphenol preparation given in diet versus drinking fluid as well as the activities of PPE versus individual catechins. We treated ApcMin/+ mice for 9 wk with 0.08% (-)-epigallocatechin-3-gallate (EGCG), 0.08% (-)-epicatechin-3-gallate, or 0.12% PPE in drinking fluid or diet. Only 0.12% dietary PPE and 0.08% EGCG in drinking fluid significantly decreased tumor multiplicity (70% and 51%, respectively). Compared to PPE in drinking fluid, dietary PPE delivered twofold more EGCG to the small intestine. Immunohistochemistry showed that adenomas in groups treated with PPE and EGCG had decreased cell proliferation, Beta -catenin nuclear expression, and phospho-Akt levels; higher cleaved caspase-3 levels, and partially restored retinoid X receptor alpha expression. The results suggest that these molecular events contribute to the cancer prevention activity of EGCG and PPE. Furthermore, diet appears to be a better route of administration for PPE than drinking fluid. [ABSTRACT FROM AUTHOR]