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Computational fluid dynamics (CFD) simulations of laboratory flume tests on thickened tailings were conducted to highlight the factors that may influence the slopes of final profiles achieved in such flumes. The numerical model was first validated against the analytical solution of a sheet of Bingham fluid on a flat plane at flow stoppage. It was then used to investigate the influence of several factors on the average slopes of the final profiles. The results show that an increase of volume, energy, flume width or base angle reduces the resulting slope angle. Moreover, the yield stress of the fluid generally has more influence on the final profiles than the viscosity. In addition, the viscosity tends to have less influence on the formation of the final profiles if the inertial effects are relatively weak. Finally, two dimensionless parameters are proposed to establish the relationship between the average slope, rheological properties, and geometrical parameters for planar deposition of thickened tailings in both sudden-release (S-R) and discharge flume tests. These results provide a better understanding of the deposition of thickened tailings in the field. The agreement between simulation results and laboratory observations in the literature gives confidence in the veracity of the computational results.Key words: thickened tailings, flume test, beach slope, computational fluid dynamics (CFD) modelling.Des simulations de la dynamique numerique des fluides (DNF) d'essais en canal de laboratoire sur des residus epaissis ont ete menees afin de mettre en evidence les facteurs susceptibles d'influencer les pentes des profils finaux obtenus dans ces canaux. Le modele numerique a d'abord ete valide contre la solution analytique d'une feuille de fluide de Bingham sur un plan plat a l'arret de l'ecoulement. Il a ensuite ete utilise pour etudier l'influence de plusieurs facteurs sur les pentes moyennes des profils finaux. Les resultats montrent qu'une augmentation du volume, de l'energie, de la largeur du canal ou de l'angle de base reduit l'angle de pente resultant. De plus, la limite elastique du fluide a generalement plus d'influence sur les profils finaux que la viscosite. De plus, la viscosite tend a avoir moins d'influence sur la formation des profils finaux si les effets inertiels sont relativement faibles. Enfin, deux parametres adimensionnels sont proposes pour etablir la relation entre la pente moyenne, les proprietes rheologiques et les parametres geometriques pour le depot planaire de residus epaissis dans les essais a deversement soudain (<< S-R >>) et dans les canaux de decharge. Ces resultats permettent de mieux comprendre le depot de residus epaissis sur le terrain. L'accord entre les resultats de la simulation et les observations de laboratoire dans la litterature donne confiance dans la veracite des resultats de calcul. [Traduit par la Redaction]Mots-cles : residus epaissis, essais en canal, pente de la plage, modelisation de la dynamique numerique des fluides (DNF)., 1. IntroductionThe beach slope developed by tailings slurry after it is discharged into a tailings storage facility (TSF) is of great importance for the design and operation of a TSF [...]

Malnutrition is a state of altered body composition and body cell mass due to inadequate intake or utilization of energy or nutrients, leading to physical and mental dysfunction and impaired clinical outcomes. As one of the most common geriatric syndromes, malnutrition in the elderly is a significant risk factor for poor clinical outcomes, causing a massive burden on medical resources and society. The risk factors for malnutrition in the elderly are diverse and include demographics, chronic diseases, and psychosocial factors. Presently, recommendations for the prevention and intervention of malnutrition in the elderly are not clear or consistent in China. This consensus is based on the latest global evidence and multiregional clinical experience in China, which aims to standardize the prevention and intervention of malnutrition in the elderly in China and improve the efficacy of clinical practice and the prognosis of elderly patients. [ABSTRACT FROM AUTHOR]

Background: There was no previous report on the three-dimensional simultaneous non-contrast angiography and intra-plaque hemorrhage (3D-SNAP) magnetic resonance imaging (MRI) sequence to diagnose intracranial artery dissection (IAD). Purpose: To improve the diagnostic accuracy and guide the clinical treatment for IAD by elucidating its pathological features using 3D-SNAP MRI. Material and Methods: From January 2015 to September 2018, 113 patients with suspected IAD were analyzed. They were divided into IAD and non-IAD groups according to the spontaneous coronary artery dissection (SCAD) criteria. All patients underwent 3D-SNAP, 3D-TOF, T2W imaging, 3D-PD, 3D-T1W-VISTA, and 3D-T1WCE) using 3.0-T MRI; clinical data were collected. The IAD imaging findings (intramural hematoma, double lumen, intimal flap, aneurysmal dilatation, stenosis, or occlusion) in every sequence were analyzed. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic efficiency of each sequence. Results: There was a significant difference in the probability of intramural hematoma, relative signal intensity of intramural hematoma, double lumen, stenosis, or occlusion signs on 3D-TOF, T2W, 3D-PD, 3D-T1W-VISTA, 3D-SNAP, and 3D-T1WCE sequences (P <0.05). The 3D-SNAP and 3D-T1WCE sequences were most sensitive for diagnosing intramural hematoma and displaying double-lumen signs, respectively. The diagnostic efficiency of the 3D-SNAP sequence combined with 3D-T1WCE was the highest (area under the curve [AUC] 0.966). The AUC value of the 3D-SNAP sequence (AUC 0.897) was slightly inferior to that of 3D-T1W enhancement (AUC 0.903). Conclusion: 3D-SNAP MRI is a non-invasive and effective method and had the greatest potential among those methods tested for improving the diagnostic accuracy for IAD. [ABSTRACT FROM AUTHOR]

In thickened tailings disposal operations, the yield stress, which is a unique physical property of thickened tailings, is a key design parameter as it has a controlling influence on the final slope of deposited tailings. A quick but rough estimate of the yield stress is typically obtained using a mini-slump test in industry. This paper explores the feasibility of using a laboratory flume test to measure the yield stress of thickened tailings. The model of slow sheet flow (SSF) which has previously been used to model flume tests and the Fourie and Gawu (FG) model, which was developed for interpretation of flume tests on thickened tailings, are compared. The SSF model, derived within the framework of long-wave approximation, is shown to only hold for flumes with frictionless sidewalls (or very wide flumes), whereas the FG model is valid for flumes of finite width and nonslip sidewalls. These findings were confirmed using CFD simulations of laboratory flume tests with nonslip and free-slip sidewalls on materials with yield stresses ranging from 20 to 60 Pa. Simulations to investigate the sensitivity of the final beach profile in the flume test to variations of yield stress and viscosity were performed. The results suggest that the final profile is very sensitive to yield stress variation but relatively insensitive to viscosity variation. This relative insensitivity to viscosity further justifies the use of the FG model for evaluation of yield stress from flume test data, as this model ignores the effect of viscosity. Simulations of mini-slump tests were conducted to demonstrate that different mould lifting velocities may introduce different inertial effects, thereby impacting the final profile and hence the yield stress extrapolated from slump tests. Moreover, comparison between the profiles predicted by several theoretical models for slump tests and CFD simulation results revealed that the existing models are not capable of capturing the final shape of the slumped material, which is invariably distorted by the mould friction to some extent. Consequently, the accuracy of the yield stress extrapolated from mini-slump tests is not high. The small errors in yield stresses calculated from the CFD simulation results using the FG model suggest that yield stresses may be determined from flume tests with very high accuracy using the FG model. [ABSTRACT FROM AUTHOR]

In the rapidly evolving application of surface deposition of high density, thickened tailings (paste), a key design parameter is the yield stress. A method widely used in industry to obtain quick and easy measurements of the yield stress is the slump test. This paper investigates current techniques for interpreting the cylindrical slump (or mini-slump) test. The lifting process of the cylindrical mould was taken into account in numerical simulations using a computational fluid dynamics (CFD) approach. Simulations with different mould lifting velocities were carried out to understand the influence of mould lifting velocity. Therefore, the influence of plastic viscosity and yield stress on mini-slump test results was studied using a mould lifting velocity of 0.01 m/s, which is representative of rates used in laboratory tests. The predicted slump and spread from mini-slump test simulations for three different scenarios ( v lifting = 0.002 m/s, v lifting = 0.01 m/s, and without mould lifting process, i.e. instantaneous disappearance of the mould) were compared to those from laboratory experiments on kaolin. The rheological properties of the kaolin were measured using a vane viscometer and the data used directly in the modelling study. The results suggest that the lifting speed of the mould has a significant influence on the mini-slump test result, which must therefore be taken into account in both numerical simulations and laboratory tests. It was found that the variation of mould lifting velocity had a greater influence on slump than spread, indicating that spread is a more appropriate measurement for determining the yield stress in a mini-slump test. This was particularly true for relatively low yield stresses (e.g. 60 Pa or less), which are values typical of most thickened tailings deposits currently operating internationally. [ABSTRACT FROM AUTHOR]

Objectives: Genome-wide association studies (GWAS) have demonstrated that the single nucleotide polymorphism (SNP) MAP3K1 rs889312 is a genetic susceptibility marker significantly associated with a risk of hormone-related tumors such as breast cancer. Considering steroid hormone-mediated signaling pathways have an important role in the progression of gastric cancer, we hypothesized that MAP3K1 rs889312 may be associated with survival outcomes in gastric cancer. The purpose of this study was to test this hypothesis. Methods: We genotyped MAP3K1 rs889312 using TaqMan in 884 gastric cancer patients who received subtotal or total gastrectomy. Kaplan-Meier survival analysis and Cox proportional hazard regression were used to analyze the association between MAP3K1 rs889312 genotypes and survival outcomes of gastric cancer. Results: Our findings reveal that the rs889312 heterozygous AC genotype was significantly associated with an increased rate of mortality among patients with diffuse-type gastric cancer (log-rank P = 0.028 for AC versus AA/CC, hazard ratio [HR] = 1.32, 95% confidence interval [CI] = 1.03–1.69), compared to those carrying the homozygous variant genotypes (AA/CC). Additionally, univariate and multivariate Cox regression analysis demonstrate that rs889312 polymorphism was an independent risk factor for poor survival in these patients. Conclusions: In conclusion, we demonstrate that MAP3K1 rs889312 is closely correlated with outcome among diffuse-type gastric cancer. This raises the possibility for rs889312 polymorphisms to be used as an independent indicator for predicting the prognosis of diffuse-type gastric cancer within the Chinese population. [ABSTRACT FROM AUTHOR]

A novel type of silicon rubber composite with benzoxazine resins (BZs) and ZrO2 was prepared. The ablative response of the composites was investigated. The results showed that the composites with BZs had superior thermal stability and higher resides compared to the pristine composites. The linear ablation rate of the composites decreased significantly with the increase in ZrO2 content. The maximum back-face temperature of the burnt samples was no more than 100 °C for the obtained composites. Three major ablation processes were carried out simultaneously during the ablation processing. These mainly involved the carbonization of the composite, and the formation of ceramic compounds such as SiC and ZrC, as well as the shielding effect of the ablated layer, which subsequently enhanced the ablation resistance of the composites. [ABSTRACT FROM AUTHOR]

Abstract: The supercapacitive performances of Co(OH)2/Ni(OH)2 composites in lithium hydroxide solution are investigated in detail. Cyclic voltammetries and galvanostatic charge/discharge measurements reveal that LiOH is the most suitable electrolyte for the composite electrodes among MOH (M=Li, Na and K). The redox behavior of the Co(OH)2/Ni(OH)2 composites different to that of the pure components shows that weight ratio of Co(OH)2/Ni(OH)2 exerts a great influence on the capacitive performances. After 1000 continuous charge/discharge cycles, the capacitance retention ratio for the composite electrode with the weight ratio of 2/3 is elevated from 41.6% to 88.2% compared with pure Ni(OH)2 electrode, exhibiting improved long-life cyclability. [Copyright &y& Elsevier]

Lung squamous cell carcinoma (LUSC) and lung adenocarcinoma (LUAD) are the two major subtypes of non-small-cell lung cancer (NSCLC). This study aimed to compare mRNA and circRNA expression patterns between LUSC and LUAD. Cancer tissues from 8 LUSC patients and 12 LUAD patients were collected to obtain mRNA and circRNA expression profiles. The differentially expressed mRNAs (DEmRNAs) and circRNAs (DE-circRNAs) between LUSC and LUAD were screened. Afterwards, miRNA-DEcircRNA pairs and miRNA-DEmRNA pairs were predicted to construct a competing endogenous RNAs (ceRNAs) network, followed by functional enrichment analysis and survival analysis. In total, 635 DEmRNAs and 245 DEcircRNAs were obtained. The ceRNA analysis revealed that genes, such as EPHA2, EPHA7, NTRK2, CDK6, hsa&#95;circ&#95;027570, hsa&#95;circ&#95;006089, and hsa-circ&#95;035997, had distinct expression patterns between LUSC and LUAD. Also, functional enrichment analysis indicated that DEmRNAs were mainly enriched in ERK1 and ERK2 cascade. Survival analyses suggested that STXBP1 and PMEPA1 were associated the prognosis of with both LUAD and LUSC, whereas EPHA2 and CDK6 might serve as prognostic factors for LUSC and LUAD, respectively. In conclusion, genes such as EPHA2, EPHA7, NTRK2, and CDK6 had different patterns in the two major histological subtypes of NSCLC. Notably, EPHA2 and CDK6 might be considered as potential therapeutic targets for LUSC and LUAD, respectively.

Breast cancer is the most common malignancy and the leading cause of cancer deaths in women worldwide. While specific genetic mutations have been linked to 5-10% of breast cancer cases, other environmental and epigenetic factors influence the development and progression of the cancer. Since unique mutations patterns have been observed in individual cancer samples, identification and characterization of the distinctive breast cancer molecular profile is needed to develop more effective target therapies. Until recently, identifying genetic cancer mutations via personalized DNA sequencing was impractical and expensive. The recent technological advancements in next-generation DNA sequencing, such as the semiconductor-based Ion Torrent sequencing platform, has made DNA sequencing cost and time effective with more reliable results. Using the Ion Torrent Ampliseq Cancer Panel, we sequenced 737 loci from 45 cancer-related genes to identify genetic mutations in 105 human breast cancer samples. The sequencing analysis revealed missense mutations in PIK3CA, and TP53 genes in the breast cancer samples of various histologic types. Thus, this study demonstrates the necessity of sequencing individual human cancers in order to develop personalized drugs or combination therapies to effectively target individual, breast cancer-specific mutations.