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The pore-water pressure response during vibratory pile driving considerably affects the piling process and environment. With the applications of high-frequency technology in upgrading the vibratory hammer, the pore-water pressure variation under high-frequency driving conditions becomes more complicated. However, there is a lack of relevant detailed investigations. This paper conducts an in situ experiment with a comprehensive monitoring and measuring system to examine the pore-water pressure response in the complete process of high-frequency vibratory pile driving. The real-time variations of pore-water pressure at the pile-soil interface and surrounding soil are evaluated, respectively. Furthermore, the excess pore-water pressure distributions and evolutions are analyzed in-depth. Then, the mechanism analysis and affected zone range determination are performed based on the development of excess pore-water pressure. The analysis results indicate that vibratory pile driving with high frequency leads to an increase of excess pore-water pressure and consequently soil quasi-liquefaction at the pile-soil interface. The apparent accumulation of excess pore-water pressure concentrates in the local range of soil around the pile tip and decays rapidly in the radial direction. According to the field observations, the increase of the pore-water pressure in the surrounding soil is attributed to the frictional penetration of the pile tip and the frictional vibration of the pile shaft. Furthermore, the maximum radial radii of the fully and partially quasi-liquefied zones are approximately 2.9 and 3.6 times the pile diameter, respectively. [ABSTRACT FROM AUTHOR]

Metros are critical infrastructure in big cities and evaluation of their safe operation is of increasing importance. To make a reasonable safety evaluation for the metro during operation, this paper establishes a rational safety evaluation model based on long-term monitoring data of Shanghai Metro Line 2. Four evaluation indicators, i.e., absolute settlement, relative curvature, deformation rate and curvature radius, are adopted. Analytic hierarchy process (AHP) and entropy method are combined to determine the weights of the indicators. The risk level values at different mileage are calculated and five danger levels are defined accordingly to determine the safety state of Shanghai Metro Line 2, i.e., safe, relatively safe, critical, relatively dangerous, and dangerous. Safety evaluation of Shanghai Metro Line 2 shows that: 83.81% areas of Shanghai Metro Line 2 are in safe, relatively safe and critical states, while 15.63% and 0.57% areas are in relatively dangerous and dangerous states, respectively; the parts of Shanghai Metro Line 2 where the risk level value exceeds the critical value are mainly distributed around the mileage at 6.0–7.5 km and 8.5–11.0 km, and the risk level value peaks around the mileage at 7.3 km, in which high attention should be attached and relevant protective measures be taken; the sections with the high risk level value coincide with the distinctly deforming areas of the metro, indicating that this evaluation method is valid. [ABSTRACT FROM AUTHOR]

The exploration of high-performance solution-processible host materials for blue and white electrophosphorescent devices is a key and fundamental challenge in the ongoing development of organic semiconductors. Herein, two solution-processible resonance host materials with self-adaptive characteristics are delicately designed and constructed. Because of the dynamic tautomerization upon resonance variation, these smart hosts show self-adaptive and selectively enhanced charge carrier flux at high triplet energy levels. Conferred by the resonance molecules, solution-processed blue and white devices exhibit excellent maximum current efficiencies (CEs) of 29.8 and 57.3 cd A−1, and external quantum efficiencies (EQEs) up to 14.5% and 23.5%, respectively. Our works highlight the significant progress of the solution-processed phosphorescent organic light-emitting diodes (PhOLEDs) using resonance host molecules, potentially furnishing a leap forward in constructing advanced organic semiconductors for next-generation optoelectronic devices. [ABSTRACT FROM AUTHOR]

In practice, dewatering for pressure relief is commonly undertaken during ongoing excavation to secure bottom stability against basal upheaval. Simultaneously, through unloading, wall deflection is obviously observed. Noticing that both cause soil deformations, this research is to study the effect of wall deformation on dewatering-induced settlement. A coupled numerical analysis of finite-difference software is employed to model Shanghai soft soils under multi-aquifer-aquitard systems (MAASs) by analyzing the results in association with an empirical approach. Consequently, through gradual force reduction, shear strength at soil-wall interface is significantly diminished. As wall deformation increases instantaneously upon lower loading, wall surface becomes deformedly bending; this condition causes the challenge to workability of shear strength. Moreover, wall deformation caused by unloading affects dewatering-induced settlement substantially. Under smaller loading, large wall deflection is observed; soil plane of failure caused by both sliding and compression occurs along slip curve, with weaker shear-strength soils at rD = 0.4 and stronger shear-strength soils between rD = 0.4 and rD = 0.65, where rD is the distance from the wall that is normalized by the depth measured from ground surface. During dewatering, stronger soils tend to drag weaker soils upward to reduce large differential settlements caused by additional compression. Consequently, settlement becomes larger at rD = 0.4 and smaller at rD = 0.65. Remarkably, at rD > 2.3, both settlement curves that result from numerical analysis and empirical method show overlapping; this indicates that the unloading effect on dewatering-induced settlement at rD > 2.3 is insignificant. Furthermore, as wall reaches maximum allowable wall deflection by 67% applied force, additional compression caused by dewatering after loading remains smaller than that under 70% applied force, contributing to smaller dewatering-induced settlement. [ABSTRACT FROM AUTHOR]

Existing solutions for axisymmetric active earth pressure are based on certain hypotheses of the circumferential stress, lacking of strict basis. This article presents a technique for deriving the actual circumferential stress according to the circumferential geometric condition, the Drucker-Prager criterion and incremental theory. Based on the actual circumferential stress, a new characteristics method for determining the axisymmetric active earth pressure in plastic flow is developed in this article. In this new method, the inclined angle of boundaries, interface friction of contact interface, dilatation effect and flow velocity of soil are considered at the same time. The validity of the new method is confirmed using several sets of experimental data from the literature. The pressure coefficients are investigated individually in detail, and some different conclusions are found. Finally, a practical formula for calculating axisymmetric active earth pressure is presented based on the linear superposition principle, and related tables of coefficients are also provided for engineering application. [ABSTRACT FROM AUTHOR]

Pumping artesian water from porous media inevitably reduces the groundwater head and promotes soil consolidation, which may result in regional land subsidence. In this study, a fluid-mechanical coupled numerical model is developed to investigate the dewatering-induced groundwater drawdown and deformation responses for multi-layer strata. The relation between the stratum deformation and groundwater drawdown is discussed. The results show that the pumping process can be divided into four stages. The development of vertical deformation is inconsistent with the change of the pore pressure for the strata except for the confined aquifer at the early stage of pumping. The strata expand while the pore pressures reduce. This inconsistency may be due to the large unloading in the confined aquifer at the early stage of pumping. Soil arch comes into being owing to the constraint of the surrounding soils when the large unloading occurs in the confined aquifer; this can reduce the stratum compression and cause the expansion of the layers. It can be concluded that as the pumping continues, the decrease of the pore pressure dominates the vertical deformation and results in the soil compression in all strata. [ABSTRACT FROM AUTHOR]

In order to prevent the inrushing caused by deep excavations, dewatering measure has to be adopted to decrease the confined water level. In this study, the responses of the strata and supporting system to dewatering in deep excavations are investigated through numerical simulations and case studies. Coupled fluid-mechanical analyses are performed by the use of the numerical software, FLAC3D. The responses of the ground settlement, base heave and interior columns to the excavation and dewatering are analyzed. Numerical results indicate that the dewatering measure can effectively reduce the uplift of the subsurface soil in the excavation, and decrease the vertical displacement of the supporting system. In addition, field data of two case histories show the similar responses and confirm the validation of the numerical results. Based on the analyses, dewatering in the confined aquifer is recommended as a construction method for controlling the vertical displacement of the strata and supporting system in deep excavations. [ABSTRACT FROM AUTHOR]

The importance of aldehyde oxidase (AOX) is becoming increasingly recognized in the prediction of human pharmacokinetic parameters from animal data. The objectives of these studies were to ascertain whether an in vitro- in vivo correlation existed in the clearance and metabolic pathways of AOX substrates and to establish whether the minipig represented an appropriate non-rodent model for man in the pre-clinical development of drugs metabolized by AOX. Using the AOX substrates carbazeran, 6-deoxypenciclovir and zaleplon, clearance was estimated from in vitro depletion experiments with minipig and human liver cytosol and microsomes and scaled before comparison with data generated in parallel in vivo studies in minipigs. In vitro and in vivo metabolic pathways were characterized by LC-MS/MS. Scaling of in vitro metabolism data to predict in vivo clearance underestimated in vivo values, although the rank order of clearance for the three compounds was preserved. Prediction of human in vivo clearance from scaled minipig in vivo data produced results which correlated well with published clinical values. Overall, this study is the first to compare minipig in vitro metabolism data with in vivo pharmacokinetic data for compounds metabolized by AOX and provides a scientific rationale for the selection of this species as a model for humans in the development of drugs which are substrates of AOX. [ABSTRACT FROM AUTHOR]

A wide variety of 3-arylbenzo[ f]quinoline-1,2-dicarboxylates and their dehydro derivatives have been synthesized by one-pot, three-component reaction of an aromatic aldehyde, naphthalene-2-amine, and dimethyl but-2-ynedioate in the presence of SnCl under reflux in acetonitrile. This procedure has several advantages, for example high yield, short reaction time, easy work-up, little pollution, and low price of the catalyst. [ABSTRACT FROM AUTHOR]

Climbing capacity of invasive climbers is an important parameter to evaluate in the species invasive potential and processes in forests. However, this feature has not attracted the attention of invasion biologists. In the present study, we assessed the climbing traits and capacity of Mikania micrantha; a herbaceous invasive stem-twiner by supplying artificial vertical supports of different sizes ranging from 1.0 to 8.0 cm in diameter. We also calculated the theoretical maximum usable host size of a M. micrantha shoot based on confirm of the hypothesis that curvature of M. micrantha shoots will remain constant and not affected by support pole size. A total 164-tested M. micrantha shoots ascended the supports successfully. Shoot success rate declined significantly when support diameter exceeded 5.0 cm. The largest pole M. micrantha ascended successfully was 6.6 cm, while the theoretical value is 7.5 cm on average. Curvature declined significantly with increasing shoot diameter. However, no significant correlation was detected between curvature and support diameter, and most M. micrantha shoots maintained relatively constant curvature within a small fluctuation range (0.1-0.2 cm) near the average value (0.16 cm). We compared our results with the only two similar studies available, and concluded that climbing shoot ascent angle on supports decreased with increasing support diameter, while curvature remained constant, which was not affected by support size. These appear to be common attributes for herbaceous stem-twiners. Maximum usable host size was an important factor for successful M. micrantha ascent. We recommend this as a vital criterion in species management. [ABSTRACT FROM AUTHOR]

Mikania micrantha (Asteraceae) is one of the 10 most invasive weeds in the world and has caused tremendous economic and environmental losses in southern China. The dodder Cuscuta campestris (Convolvulaceae) is a native holoparasite that can parasitize and suppress M. micrantha, and thus is recommended as an effective control agent. However, the natural growth of dodder lags behind that of M. micrantha and fails to exert direct year-round suppression. To verify the effective parasitic distance, we placed a dodder seedling at a designated distance from the stem of M. micrantha and monitored coiling, haustorium formation, and survival. To verify suitable host stems for the parasite, we grew M. micrantha for more than 6 months to form stems of different sizes, taped dodder seedlings to the stems, and monitored. We used various temperatures to determine the effect on dodder seed germination and M. micrantha sprouting. The results showed that a dodder–host distance of 4 cm decreased the probability of successful parasitism to 0; dodder seedlings cannot parasitize M. micrantha stem diameters ≥0.3 cm; and the temperatures for the highest dodder seed germination and M. micrantha sprouting are 26 and 30 °C, respectively. We conclude that the lack of suitable M. micrantha parts within the dodder’s effective parasitism distance is the major cause of restricted dodder parasitism and that the lower temperature for the highest dodder germination compared to that for the highest M. micrantha sprouting may decrease the possibility of parasitism. To acquire aggressive parasitism, dodder should be manually assisted by dispersing its vegetative form. [ABSTRACT FROM AUTHOR]

Although many studies have shown that drug delivery and efficacy can be improved by nano-sized drug carriers, we understand little regarding their pharmacokinetics (PK). PK calculations for drugs delivered by carriers are more complex than those for drug-only solutions. The overall PK depends on many factors, including drug-release rate and the PK of both the drug itself and the carrier. We built a mathematical model to describe the intracellular PK of paclitaxel delivered by nanoparticles. Paclitaxel was incorporated into poly (lactic-co-glycolic acid) nanoparticles, which were chemically labeled with a fluorescence probe for quantification. PK profiles of drug alone, nanoparticles alone, and drug delivered by nanoparticles were studied in human breast cancer MCF7 cells. Simulated results from the model were similar to observed data, indicating that the model was properly developed. The model clearly and quantitatively represented the effects of relative factors, such as drug dose, drug-release kinetics, and nanoparticle PK, on the PK of paclitaxel delivered by nanoparticles. We also used this model to estimate the intracellular drug-release rate, which was found to be slightly slower than the in vitro release rate in this study. This mathematical model could be used to provide guidelines to design, evaluate, and optimize nano-sized drug carriers. [ABSTRACT FROM AUTHOR]

The rapidly evolving nanotechnology field highlights the need of better understanding the relationship between nanoparticle (NP) properties and NP transport in solid tumors. The present study tested the hypothesis that the diffusive transport and spatial distribution of NP can be predicted based on the following parameters: interstitial NP diffusivity, NP-cell interaction parameters (cell surface binding capacity, rate constants of association, dissociation, and internalization). We (a) established the models and equations; (b) experimentally measured, in monolayer pharynx FaDu cells, the model parameters for three NP formulations (negatively charged polystyrene beads, near-neutral liposomes, and positively charged liposomes, with respective diameter of 20, 110, and 130 nm); and (c) used the models and parameters to simulate NP diffusion in 3-dimensional (3D) systems. We next measured the NP concentration-depth profiles in tumor cell spheroids, an avascular 3D system, and found good agreement between model-simulated and experimental data in spheroids for the negative and neutral NP (>90% predicted data points at three NP concentrations and three treatment times were within the 95% confidence intervals of experimental data). Model performance was inferior for positive liposomes containing a fusogenic lipid. The present study demonstrated the possibility of using in vitro NP-cell biointerface data in monolayer cultures with in silico studies to predict the NP diffusive transport and concentration-time-depth profiles in 3D systems, as functions of NP concentrations and treatment times. Extending this approach to include convective transport may yield a cost-effective means to predict the NP delivery and residence in solid tumors. [ABSTRACT FROM AUTHOR]

Soil microbes contribute to native plant species successful resistance against invasive plant. Three native tree species, Heteropanax fragrans (HF), Cinnamomum burmanii (CB), and Macaranga tanarius (MT) were effective in controlling the notorious invasive vine Mikania micrantha (MM). Biomass production and allocation patterns (shoot/root biomass ratio (shoot/root)) are important indicators of MM climbing coverage and competitive light-capturing capacity. An investigation was conducted to test the role of soil microbes associated with the three native tree species to inhibit MM biomass production and shift MM shoot/root. Rhizosphere soils originating from preculture HF, CB, MT, and MM plots were collected separately for use as inocula. The inocula were mixed with sterilized river sand at a 1:9 (w/w) ratio to grow MM. The fungicide carbendazim (methyl benzimidazol-2-ylcarbamate) was applied to half the treatments to kill pathogenic soil fungi. Two nutrient levels were established based on the natural soil nutrient concentration from a field stand invaded by MM. MM were grown from seeds in a glasshouse, harvested 15 weeks after sowing, and separated into shoot and root portions. Results showed that under interaction of soil origin and nutrient levels, MM biomass production was unchanged, but biomass allocation patterns were significantly different. MM biomass production grown in the three native tree soils under two nutrient levels was similar or higher than MM biomass production in MM conspecific soil, indicating the absence of species-specific pathogens that inhibited MM biomass production in native tree soils. However, in both conspecific and tree soils, MM biomass production was significantly reduced in the presence of pathogenic soil fungi, i.e. MM experienced significant fungal inhibition, demonstrating the pathogenic soil fungi promoted native tree resistence to MM. MM exhibited decreased shoot biomass allocation when cultivated in native tree soil relative to MM conspecific soil under field stand nutrient level conditions. Reduced resource allocation to shoot biomass could result in diminished capacity to climb, cover, and subsequent smother to native trees, and reduced surface area exposed to available light. Following fungicide application, significant biomass allocation differences disappeared, suggesting the native tree soil fungi were responsible for decreasing MM shoot biomass. The overall results indicated tree soil fungi serve an integral role in controlling invasive MM through fungal inhibition on MM biomass production, and shifts in MM biomass allocation patterns. [ABSTRACT FROM AUTHOR]

Dapivirine, a non-nucleoside reverse transcriptase inhibitor, is a potent and promising anti-HIV molecule. It is currently being investigated for use as a vaginal microbicide in two-dosage forms, a semi-solid gel and a silicone elastomer ring. Quick-dissolving films are promising and attractive dosage forms that may provide an alternative platform for the vaginal delivery of microbicide drug candidates. Vaginal films may provide advantages such as discreet use, no product leakage during use, lack of requirement for an applicator for insertion, rapid drug release, and minimal packaging and reduced wastage. Within this study, the in vitro bioactivity of dapivirine as compared with the non-nucleoside reverse transcriptase inhibitor UC781 was further established, and a quick dissolve film was developed for vaginal application of dapivirine for prevention of HIV infection. The developed film was characterized with respect to its physical and chemical attributes including water content, mechanical strength, drug release profile, permeability, compatibility with lactobacilli, and bioactivity. The anti-HIV activity of the formulated dapivirine film was confirmed in in vitro and ex vivo models. Importantly, the physical and chemical properties of the film as well as its bioactivity were maintained for a period of 18 months. In conclusion, a vaginal film containing dapivirine was developed and characterized. The film was shown to prevent HIV-1 infection in vitro and ex vivo and have acceptable characteristics which make this film a promising candidate for testing as vaginal microbicide. [ABSTRACT FROM AUTHOR]

Merremia boisiana (Gagnep) van Ooststr. is a noxious fast growing woody vine and is able to grow overtop other plants, causing the death of plants underneath and forming monospecies stands. To formulate management responses, we assessed its seed and vegetative reproduction efficacy through indoor and field experiments. The number of flowers counted from bagged infructescences in Guangzhou ranged from 25 to 172, with an average of 80.80. Counting the seeds of bagged infructescences had shown that there were only 1.58 hard testa seeds in each infructescence. Seed vitality tests using red ink indicated that only 68.6% of hard testa and filled seeds were viable. The emergence rate of scarified hard testa seeds in the sand bed was 31.96%. Under imitated natural conditions, 8% of hard testa seeds could germinate, and 9% still retained their germination potential in one year. Thus, seedlings should be monitored and removed in a timely fashion after any attempt of clearing. Moving soil or transplanting plant from infested patches should be strictly prohibited at least for several years. All considered, an infructescence contributed 0.3 seedlings. The investigation in the field found no seedlings either inside or at the perimeter of the patch, suggesting scant expansion by means of seed dispersal. Therefore, the elimination effort could be focused on a relatively restricted scale of patches. Of 630 cuttings of young shoots, old shoots and old lying shoots with or without growth regulators, there were only four (or 0.63%) established individuals. Air-layering shoots all died in two months. Poor cuttings and air-layering reproduction indicated that regeneration from fragments of removed stems or accidentally dropped ones was quite unlikely, and thus mechanical removal was safe. [ABSTRACT FROM AUTHOR]

Three oldfield annual species ( Abutilon theophrasti Medic., Ambrosia artemisiifolia L. and Setaria lutescens (Weigel) Hubb.) were investigated. All three developed substantial mycorrhizal infections when inoculated with Glomus etunicatum Becker & Gerd. Mycorrhizal infection dramatically increased phosphorus content and dry weight of both Abutilon and Ambrosia, but did not significantly affect dry weight and only modestly increased phosphorus content of Setaria. These results were consistent with a lower level of infection and much greater root density in Setaria than in the other species. When Abutilon was grown in the presence of Setaria, mycorrhizal infection had no effect on Abutilon phosphorus content or dry weight. The depressive effect of Setaria on the response to inoculation in Abutilon was probably not caused by water soluble allelopathic chemicals from Setaria roots, but soil leachate from Abutilon plants did inhibit infection in other Abutilon plants. The data were consistent with the hypothesis that the very high root density and effective soil exploitation of Setaria reduced the benefit from mycorrhizal infection in Abutilon via phosphorus depletion in a large proportion of the available soil volume. Furthermore, even if mycorrhizal infection were capable of increasing phosphorus content of Abutilon in the presence of Setaria, the very high competitive ability of Setaria for nitrogen in the soil could have reduced the benefit of an enhanced phosphorus content. Carbon isotope ratios were reduced in Abutilon by mycorrhizal infection, indicating a possible reduction in water use efficiency. [ABSTRACT FROM AUTHOR]

We tested the hypothesis that mycorrhizal infection benefits wild plants to a lesser extent than cultivated plants. This hypothesis stems from two observations: (1) mycorrhizal infection improves plant growth primarily by increasing nutrient uptake, and (2) wild plants often possess special adaptations to soil infertility which are less pronounced in modern cultivated plants. In the first experiment, wild ( Avena fatua L.) and cultivated ( A. sativa L.) oats were grown hydroponically at four different phosphorus levels. Wild oat was less responsive (in shoot dry weight) to increasing phosphorus availability than cultivated oat. In addition, the root: shoot ratio was much more plastic in wild oat (varying from 0.90 in the low phosphorus solution to 0.25 in the high phosphorus solution) than in cultivated oat (varying from 0.44 to 0.17). In the second experiment, mycorrhizal and non-mycorrhizal wild and cultivated oats were grown in a phosphorus-deficient soil. Mycorrhizal infection generally improved the vegetative growth of both wild and cultivated oats. However, infection significantly increased plant lifespan, number of panicles per plant, shoot phosphorus concentration, shoot phosphorus content, duration of flowering, and the mean weight of individual seeds in cultivated oat, while it had a significantly reduced effect, no effect, or a negative effect on these characters for wild oat. Poor positive responsiveness of wild oat in these characters was thus associated with what might be considered to be inherent adaptations to nutrient deficiency: high root: shoot ratio and inherently low growth rate. Infection also increased seed phosphorus content and reproductive allocation. [ABSTRACT FROM AUTHOR]

Orthodontic retainers are wearable customizable medical devices for dental protection or alignment. Here, clonidine hydrochloride (CH)-loaded wearable personalized 3D printed orthodontic retainers were studied for local sustained-release of drugs. CH powders were mixed with PEG 4000, Tween 80, poly(lactic acid), and polycaprolactone. The mixture was hot-melt extruded to form a filament that was 3D printed to a customizable original orthodontic retainer with the fused deposition modeling (FDM) method. The original retainer showed a burst release of CH in the early stage of the dissolution process though a sustained release appeared in the late stage. The in vivo burst release of CH would lead to unexpected side effect. The original retainer was modified by coating with hydrophilic polymers or washing with buffered solutions to obtain the coated or washed retainer. The coated retainer still showed a burst release while the washed retainer showed an optimal sustained release. Many CH microparticles existed on the surface of original retainers according to the scanning electron microscopic image so that the burst release was unavoidable. The hydrophilic polymer coating method did not change the release profile because the polymer was also rapidly dissolved. However, most of the surface CH can be eliminated by washing so that the burst release dissappeared in the washed retainer. Furthermore, the simulated CH concentration-time profiles in the circulation of humans of the washed retainer showed the stable and appropriate drug levels for more than 3 days. Wearable personalized 3D printed drug-loaded orthodontic retainers are a promising drug-device for sustained release of drugs. [ABSTRACT FROM AUTHOR]

Construction of organic materials with harmonized optoelectronic properties and processabilities is important for the practical applications, especially for the solution-processed devices. Herein, three series of soft-conjugated materials designed with rigid planar molecular structures in solid state for promising optoelectronic properties and flexible non-planar conformation in solution for facile processing were constructed and theoretically investigated using thiophene and/or furan aromatic rings as the backbone and 10 pairs of non-bonding interactions as the soft bonding to conformationally lock the molecules. Computational results indicate that soft-conjugated small molecules and polymers can be efficiently established on 5-5 aromatic ring architectures with various non-bonding interaction pairs, and furan is more efficient than thiophene in constructing soft-conjugated materials due to the strong conjugation effects and low rotation hindrance between the adjacent furan-based rings. High optical and electronic properties of the soft-conjugated materials can be also achieved, showing delocalized frontier molecular orbitals with favorable energy levels for conventional device applications, strong absorption and emission bands that are comparable to the corresponding rigid-conjugated materials. These findings highlight that soft-conjugation feature would be inspirational for the development of organic electronics to overcome the intrinsic contradiction between high optoelectronic properties and good processability in organic π-conjugated small molecules and polymers. [ABSTRACT FROM AUTHOR]