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Mud slurries are characterized by high water content and low strength; therefore, treatment (which included volume reduction and strength improvement in this study) was required before they could be transported, handled, and reused more easily. This study presented a method that combined prefabricated horizontal drains, vacuum preloading, and solidification (PHDVPS) for the rapid treatment of mud slurry with high water content. The performance of the PHDVPS method was experimentally investigated and compared with traditional methods that used only vacuum preloading or only solidification. Settlement and the mass of the discharged water (mvw) were monitored in model tests to investigate the dewatering efficiency (i.e., volume reduction). Then, unconfined compressive strength (UCS), permeability, X-ray diffraction (XRD), scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP) tests were conducted to investigate the mechanical, hydraulic, and microstructural properties of the PHDVPS-treated soils. The results indicated that the PHDVPS method significantly outperformed the traditional vacuum preloading and direct solidification methods for volume reduction and strength improvement. In addition, parametric studies indicated that the initial water content (wo) of mud slurry, cement content (Aw), duration of vacuum preloading (tp), and magnitude of vacuum pressure (σvp) had a significant influence on the performance of the PHDVPS method. [ABSTRACT FROM AUTHOR]

The scale cutting of flying shear is always an important issue in the control field. This paper studies the issue through the hardware platforms in the Schneider laboratory, Donghua University. PC, motion controUer LMC058F42 , servo controUer LXM32A servo motor BMH0701 , touch screen XBGT2200 of Schneider were used to make up the hardware platform. Firstly, it introduces the hardware modules, mainly the motion controUer, servo controUer and the servo motor. Then it introduces the procedure of flying shear and the target that wiil come true. It briefly recommends the derivation process of the flying shear motion equations. The control program that uses the Somachine to achieve the algorithm is given. Finally the control of flying shear through the hardware platform comes true. It gains satisfied effect in the control precision by the deviation of cutting length less than 1 mm. And it proves the flying shear motion equations. [ABSTRACT FROM AUTHOR]

Abstract: A theoretical study is made of the consolidation of a composite foundation reinforced by columns. A more reasonable initial condition for the consolidation of a composite foundation is derived from the equilibrium equation and the equal strain assumption. Then, the general analytical solutions for excess pore water pressures in the column and in the surrounding soil are obtained using this new initial condition under the influence of several important factors. These factors include: the gradual variation of horizontal permeability in the disturbed soil, the change in the total average stress in a composite foundation with depth, and the effect of time-dependent external loads. The general expressions for the overall average degree of consolidation of a composite foundation, both in terms of stress and in terms of deformation, are then derived. On the basis of the above theory, the explicit solutions for a particular case, which considers ramp loading and a linear change of total stress with depth, are given in detailed forms. Finally, a parametric study and a comparison of some available solutions are made. The results show that the average degree of consolidation obtained in terms of stress and in terms of deformation is the same; the increase in construction time, the disturbance intensity during column construction and the size of the disturbed zone reduce the consolidation rate of a composite foundation. For the case of PTIB (pervious top surface and impervious bottom surface), the increase in the ratio of top total stress to bottom total stress in the composite foundation accelerates consolidation. [Copyright &y& Elsevier]

A one‐dimensional thaw consolidation model considering the density change from pore ice to pore water is established, and the model describes a special type of moving boundary problem with double moving boundaries. An analytical solution for the model under a time‐varying external load is developed using certain form of superposition principle and the similarity type of general solution. Some known solutions in literature can be recovered as special cases of the analytical solution once the density change from pore ice to pore water is neglected. If the thawing front was to cease at certain time, consolidation of thawed soil in a fixed region is then encountered, and an analytical solution for the post‐thawing consolidation problem is developed using the Green's function method. Computational examples of the analytical solutions are presented. First, comparison between our model and classical model of Morgenstern and Nixon (MN model) is conducted, showing the error caused by neglecting the density change from pore ice to pore water. The MN model overestimates the excessive pore water pressure at locations near the soil surface, while underestimates it at locations near the thawing front; the error caused by neglecting the density change becomes more pronounced with increasing ice content of frozen soil. Second, comparison between the thaw consolidation process under an instant load and that under a corresponding exponential load is made. The difference in thaw consolidation behavior between the two situations mainly displays during the early stage, when there is obvious discrepancy between the two external loads; the degree of consolidation and thaw consolidation settlement are more sensitive to the discrepancy in external load than the excessive pore water pressure is. [ABSTRACT FROM AUTHOR]

Mesoporous silica nanoparticles (MSNs) are promising drug carriers for use in cancer treatment owing to their excellent biocompatibility and drug‐loading capacity. However, MSN's incomplete drug release and toxic bioaccumulation phenomena limit their clinical application. Recently, researchers have presented redox responsive mesoporous organosilica nanoparticles containing disulfide (S–S) bridges (ss‐MONs). These nanoparticles retained their ability to undergo structural degradation and increased their local release activity when exposed to reducing agents. Disulfide‐based mesoporous organosilica nanoparticles offer researchers a better option for loading chemotherapeutic drugs due to their effective biodegradability through the reduction of glutathione. Although the potential of ss‐MONs in cancer theranostics has been studied, few researchers have systematically compared ss‐MONs with MSNs with regard to endocytosis, drug release, cytotoxicity, and therapeutic effect. In this work, ss‐MONs and MSNs with equal morphology and size were designed and used to payload doxorubicin hydrochloride (DOX) for liver cancer chemotherapy. The ss‐MONs showed considerable degradability in the presence of glutathione and performed comparably to MSNs on biocompatibility measures, including cytotoxicity and endocytosis, as well as in drug‐loading capacity. Notably, DOX‐loaded ss‐MONs exhibited higher intracellular drug release in cancer cells and better anticancer effects in comparison with DOX‐loaded MSNs. Hence, the ss‐MONs may be more desirable carriers for a highly efficient and safe treatment of cancer. [ABSTRACT FROM AUTHOR]

In this study, we exploited a one-pot method to fabricate cetyltrimethylammonium bromide (CTAB)-loaded Janus silver mesoporous silica nanoparticles (Janus Ag-MSNs@CTAB). These bullet-like nanoparticles had a silver head (80 nm in diameter) attached to a mesoporous silica stick (200–300 nm in length). The CTAB-loaded nanobullets exhibited a marked affinity for the bacterial cell surface and the simultaneously sustained release behavior of CTAB and silver ions. The minimum inhibitory concentrations (MIC) of Janus Ag-MSNs@CTAB were determined to be 10 μg/mL and 20 μg/mL for E. coli and S. Aureus , respectively. Importantly, Janus Ag-MSNs@CTAB provided a single-particle nanoplatform with a synergistic effect against both Gram-positive and Gram-negative bacteria. A thorough investigation indicated that CTAB induces a dramatic loss of bacterial membrane integrity, which facilitated the internalization of silver. This report described an efficient and convenient method of synthesizing Janus silver mesoporous silica nanoparticles, and these nanobullets show promising potential in biomedical applications. [ABSTRACT FROM AUTHOR]

Cadmium, a toxic heavy metal, seriously affects human health and ecological security. The cation/H+ exchanger (CAX) family is a unique metal transporter that plays a crucial role in Cd acquisition, transfer, and remission in plants. Although there are many studies related to the genome-wide analysis of Populus trichocarpa , little research has been done on the CAX family genes, especially concerning Cd stress. In this study, genome-wide analysis of the Populus CAX family identified seven stress-related CAX genes. The evolutionary tree indicated that the CaCA family genes were grouped into four clusters. Moreover, seven pairs of genes were derived by segmental duplication in poplars. Cis -acting element analysis identified numerous stress-related elements in the promoters of diverse PtrCAXs. Furthermore, some PtrCAXs were up-regulated by drought, beetle, and mechanical damage, indicating their possible function in regulating stress response. Under cadmium stress, all CAX genes in the roots were up-regulated. Our findings suggest that plants may regulate their response to Cd stress through the TF-CAXs module. Comprehensively investigating the CAX family provides a scientific basis for the phytoremediation of heavy metal pollution by Populus. [ABSTRACT FROM AUTHOR]

SUMMARY During the process of one-dimensional consolidation with a threshold gradient, the seepage front moves downward gradually, and the problem is indicated as a Stefan problem. The novel feature in this Stefan problem is a latent heat that varies inversely with the rate of the moving boundary. An exact solution for the external load that increases in proportion to the square root of time is constructed using the similarity transformation technique. Computational examples concerning the effect of different parameters on the motion of the seepage front are presented. The exact solution provides a worthwhile benchmark for verifying the accuracy of numerical and approximate methods. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Following the approach of Hansbo [4], a series of closed-form solutions for equal-strain consolidation were developed based on an axisymmetric unit cell in presence of a vertical drain, whose discharge capacity was varied by altering the depth, time or both simultaneously. The excess pore pressure and degree of consolidation were compared with Hansbo’s results. The factors affecting the calculation results were also investigated. Some conclusions were drawn regarding the distribution of the excess pore water pressure along the ground depth and the extent of consolidation considering the varied discharge capacity. [Copyright &y& Elsevier]

Abstract: The rate of consolidation by prefabricated vertical drains (PVDs) is closely related to the well resistance, which mainly depends on the discharge capacity of PVDs. According to the existing laboratory tests and field investigations, the discharge capacity of PVDs will decrease with the development of consolidation due to its deformation and siltation and so on. Based on this consideration, in this paper, the discharge capacity was assumed decreased exponentially with time, which resulted in an increase of the well resistance with time during consolidation. Then, a closed-form solution considering the time dependent well resistance for a vertical drain system was developed based on the equal strain condition. Comparisons were presented with some existing solutions for the excess pore water pressure and for the radial average degree of consolidation. The influences of the time dependent well resistance on consolidation rate were then analyzed and the application of the present solution was discussed. [Copyright &y& Elsevier]

Background: To investigate the clinicopathological characteristics of head and neck small cell carcinoma (H&NSmCC) and identify prognostic factors on the basis of the Surveillance, Epidemiology and End Results (SEER) database.Methods: Total of 789 primary cases from 1973 to 2016 were included. Univariate and multivariate analyses were performed to identify independent prognostic indicators. An H&NSmCC-specific nomogram was constructed and compared with the AJCC staging system by calculating the time-dependent area under the curve (AUC) of the receiver operating characteristic (ROC) curves.Results: The incidence of H&NSmCC peaked during the period of 50 to 70 years old, and the most frequent location was the salivary gland. The 5-year disease specific survival (DSS) was 27%. In the multivariate survival analysis, AJCC III + IV stage [HR = 2.5, P = 0.03, I + II stage as Ref], positive N stage [HR = 1.67, P = 0.05, negative N stage as Ref], positive M stage [HR = 4.12, P = 0.000, negative M stage as Ref] and without chemotherapy [HR = 0.56, P = 0.023, received chemotherapy as Ref] were independently associated with DSS. The H&NSmCC-specific nomogram was built based on the independent prognostic indicators. The nomogram demonstrated better predictive capacity than the AJCC staging system for 5-year DSS [(AUC: 0.75 vs 0.634; Harrell's C-index (95% CI): 0.7(0.66-0.74) vs 0.59(0.55-0.62), P < 0.05].Conclusion: N stage, M stage, AJCC stage and chemotherapy were independent prognostic indicators included in the prognostic nomogram model, which can better predict the survival of H&NSmCC than the AJCC staging system. [ABSTRACT FROM AUTHOR]

Background: To explore the clinicopathologic characteristics, treatment and prognostic factors of head and neck acinar cell carcinoma (HNACC) comprehensively.Methods: A population-based study was conducted using data from the Surveillance, Epidemiology, and End Results database (1975-2016). Overall survival (OS) and HNACC-specific survival of patients with different clinicopathologic variables were compared using the Kaplan-Meier method and Cox multivariate regression.Results: A total of 2624 primary HNACC cases (1052 males, 1572 females) were identified. There was a significant difference in gender distribution. Among the total cohort, 2416 cases originated from salivary glands, including 2325 parotid gland ACC cases. Regardless of confounding factors, the 10-year and 20-year disease-specific survival (DSS) was 93.6 and 90%, respectively. Surgery was favourably associated with better DSS and OS [HR = 0.13, P = 0.0092 and HR = 0.23, P = 0.0203]. Gender was the only demographic independent prognostic factor for both DSS and OS [Male vs female, HR = 3.3, P = 0.0028 for DSS; HR = 2.44, P = 0.0376 for OS]. Higher pathological grade was adversely associated with DSS and OS [Grade II, HR = 4.03, P = 0.0444; Grade III + IV, HR = 35.64, P = 0.0000 for DSS; Grade III + IV, HR = 4.49, P = 0.0000 for OS, Grade I as reference]. In addition, TNM/AJCC stage was commonly associated with prognosis.Conclusion: Surgery was the only favourable prognostic indicator for both DSS and OS. Gender, age, pathological differentiation and TNM/AJCC stage were independent prognostic factors for survival. [ABSTRACT FROM AUTHOR]

Temperature is a major factor affecting physical and mechanical rock properties. With increasing temperature, a series of variations enlarge the internal defects within rocks, resulting in physical and mechanical rock property variations. To explore the influence of temperature on the physical and micro-structure of limestone, the weighing test and P-wave velocity test were conducted on limestone after exposure to high temperature to reveal the evolution of the limestone mass and P -wave velocity. XRD, XRF, SEM, and mercury intrusion tests were also carried out to examine the mineral composition and content, micro-fracture morphology, porosity, and fractal dimension. The limestone mass and P-wave velocity decrease with increasing temperature. When T ≤ 400 °C, there is no obvious change in chemical composition and crystal structure; when T = 400–500 °C, the diffraction intensity of partial calcite decreases, and dolomite decomposes gradually; when T > 500 °C, illite decomposes gradually, while dolomite decomposes completely; and the diffraction intensity of calcite is significantly reduced. When T ≤ 200 °C, changes in trace minerals or impurities containing K2O and Na2O and the decomposition of illite oxide are dominant; when T = 400–600 °C, illite oxide, trace minerals, or impurities containing K2O and calcium hydroxide begin to decompose. When T = 600–800 °C, magnesite and dolomite begin to decompose. When T ≤ 200 °C, micro-fracture surfaces change slightly. When T = 200–500 °C, micro-fractures begin to develop and propagate gradually, most of which are intergranular cracks with a small number of transgranular cracks. When T > 500 °C, transgranular cracks occur in samples with locally broken crystals, and the cracking of the crystal structure occurs with increasing pore size. With increasing temperature, the limestone pore fractal dimension decreases gradually, and the higher the temperature, the greater the decrease. 400 °C to 500 °C is the temperature threshold interval that causes the pore structure change. These new pores, resulting from the increasing temperature, are primarily mesopores with a pore diameter of 1.0–10.0 μm. This research provides a scientific basis for the design and construction of rock engineering projects to be subjected to high temperatures, deep geological radioactive nuclear waste disposal sites, deep mines, and the exploitation of geothermal resources. [ABSTRACT FROM AUTHOR]

Abstract This study derived the analytical solutions for the deflection, bending moment and shear force of a hard roof under an arbitrary front abutment pressure for both the initial and periodic fracture problems using the elastic foundation beam model. With the assumption that the overburden pressure is constant in a small section, the roof subjected to arbitrarily distributed pressures is divided into a number of sufficiently small sections, whose closed-form solutions can be obtained easily. The proposed analytical solutions are validated by comparisons with those calculated using a model reported in the literature, in which the overburden pressure is assumed to follow a normal distribution. The parametric studies on the foundation stiffness, front abutment pressure and support resistance show that: (1) with the decrease of elastic foundation stiffness, the deflection and the maximum bending moment significantly increase, and the shear force significantly changes in the unmined region; (2) as the peak point position moves inside the coal wall, the deflection of the goaf roof, as well as the maximum bending moment and shear force, obviously decrease; (3) with the increase of support resistance, the maximum bending moment and deflection significantly decrease, and the shear force significant decreases in the hydraulic support region; (4) when the coal seam is soft and peak position of the front abutment pressure is near the coal wall, initial fracture occurs at the midspan; otherwise, it occurs inside the coal wall. For the periodic fracture condition, the fracture position is closer to the coal wall when the coal seam is harder, and the fracture length increases when the peak position of front abutment pressure moves inside the coal wall. [ABSTRACT FROM AUTHOR]

A facile method for foodborne bacterial enrichment and direct identification from milk samples using Janus magnetic mesoporous silica nanoparticles (Janus M-MSNs) is reported. The fluorescent-magnetic nanorods are fabricated using the one-pot sol-gel process, followed by modification with Escherichia coli antibodies to form fluorescent Janus M-MSNs (Janus M-MSNs-Ab). The Janus M-MSNs-Ab combine the fast magnetic response capacity of the magnetic heads with the strong fluorescence and bacterial-targeting properties of the silica bodies, which results in selective capture and fluorescence identification of E. coli from milk samples containing mixed bacteria. After magnetic separation, complexes of the bacteria and nanoparticles are detected through direct matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS), which has a strong, anti-interference performance. Thus, the Janus M-MSNs-Ab synthesized in this study show great sensitivity and effectivity in foodborne bacterial capture and is a promising tool for rapid bacterial detection and investigation when combined with MALDI-TOF-MS. [ABSTRACT FROM AUTHOR]

Berberine, an bioactive isoquinolin alkaloid from traditional Chinese herbs, is considered to be a promising agent based on its remarkable activity against hepatocellular carcinoma. However, the clinical application of this nature compound had been hampered owing to its properties such as poor aqueous solubility, low gastrointestinal absorption, and reduced bioavailability. Therefore, we developed Janus magnetic mesoporous silica nanoparticles (Fe3O4- mSiO2 NPs) consisting of a Fe3O4 head for magnetic targeting and a mesoporous SiO2 body for berberine delivery. A pH-sensitive group was introduced on the surface of mesoporous silica for berberine loading to develop a tumor microenvironment-responsive nanocarrier, which exhibited uniform morphology, good superparamagnetic properties, high drug-loading amounts, superior endocytic ability, and low cytotoxicity. Berberine-loaded Fe3O4- mSiO2 NPs exerted extraordinarily high specificity for hepatocellular carcinoma cells, which was due to the pH-responsive berberine release, as well as higher endocytosis capacity in hepatocellular carcinoma cells rather than normal liver cells. More importantly, an external magnetic field could significantly improve antitumor activity of Ber-loaded Fe3O4- mSiO2 NPs through enhancing berberine internalization. Taken together, our results suggest that Janus nanocarriers driven by the magnetic field may provide an effective and safe way to facilitate clinical use of berberine against hepatocellular carcinoma. [ABSTRACT FROM AUTHOR]

• The analytical finite strain solutions for cavity expansion in strain-hardening and strain-softening soils are derived. • The evolutions of both deformation and strength parameters are investigated. • The surrounding rock is divided into a series of perfectly plastic concentric annuli. • The solution is suitable to soil with any material properties. This paper presents an analytical finite strain solution for cavity expansion in strain-hardening and/or softening Mohr-Coulomb soil subjected to a non-associated flow rule. The evolutions of material parameters, i.e. deformation and strength parameters, are totally considered. The finite strain is applied to describe the plastic behavior with the logarithmic strain. By assuming constant material properties in a very small region, the plastic region is divided into a series of concentric annuli. The solution can be recursively obtained according to the closed-form solution of each annulus, and is suitable to soil with any complex material evolution types. For the cavity with the same cavity expansion a / a 0 , the required cavity pressure of strain-hardening and/or softening soils is larger and/or smaller than that of elasto-perfectly plastic soils for both spherical and cylindrical cavity expansions. With respect to the same cavity pressure, the displacement and stress around cavity of strain-hardening and/or softening models are larger and/or smaller than those of perfectly plastic model. With respect to the same cavity expansion displacement, the increases in the strength parameters including cohesive strength and friction enlarge the cavity pressure, and slightly decrease the plastic and residual radii. [ABSTRACT FROM AUTHOR]

Background: Malignant tumours of the temporomandibular joint (MTTMJ) are extremely rare. Studies describing its unique epidemiology, clinicopathological features, treatment and prognosis comprehensively are limited. To address these issues, current investigation was performed.Methods: A retrospective research was carried out by using population-based data from the Surveillance, Epidemiology, and End Results database (1973-2016).Results: Data for a total of 734 patients, including 376 men and 358 women, was found. The median age was 47 years. The 5-year and 10-year disease specific survival (DSS) rates were 69.2 and 63.6%, respectively. Significant differences in DSS were found according to age, race, tumour type, AJCC/TNM stage, surgery, radiotherapy, chemotherapy and different treatment modalities (P < 0.05). In the multivariate survival analysis, age > 44 years and AJCC stage III and IV were associated with poor DSS.Conclusion: MTTMJ was mostly found in white people with a median age of 47 years without any sex predominance. Patient's age and AJCC stage was independent predictor of DSS. [ABSTRACT FROM AUTHOR]

This paper presents a large strain numerical solution of a circular tunnel for the ground reaction curve (GRC) in strain-softening rock masses. Both the stress equilibrium equation and deformation compatibility equation are considered in a current coordinate. A series of examples are employed to validate the proposed solutions, and the results show that: (1) the displacement, softening and residual radii of larger strain solution are smaller than that of small strain solution, and their difference significantly increases with a decrease in the Young's modulus. (2) the increasing Poisson's ration and critical shear plastic strain decrease the displacement, softening and residual radii. [ABSTRACT FROM AUTHOR]