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Liquidity index is used to measure the relative consistency of natural soils, making it possible to evaluate the stiffness degree and strength of clays. However, a systematic understanding of the relationship between the undrained shear strength and the liquidity index remains unclear. While some studies are being conducted on this putative relationship, the theoretical foundation is still lacking. This study proposes a new undrained shear strength prediction model based on the Mohr–Coulomb failure criterion and the critical state theory. A database of 103 soil samples from 18 research is utilised to validate the model's applicability. The results reflect a consistent level of accuracy. The proposed model has an obvious advantage and has potential for predicting the undrained shear strength of clays. [ABSTRACT FROM AUTHOR]

The cement composite calcium lignosulfonate is used to enhance the mechanical properties and the freeze–thaw resistance of loess. Based on an unconfined compressive test under different freeze–thaw cycles, the influence of cement dosage, curing age, and freeze–thaw cycles on compressive strength are discussed. The results indicate that the strength of loess can increase by up to 13 times, and the loss of strength is reduced from 72% to 28% under the reinforcement of cement dosage and curing age. The loss of strength is mainly concentrated in the initial 5 freeze–thaw cycles, and the structure gradually stabilizes after 10 freeze–thaw cycles. In addition, according to the X-ray diffraction test, it is found that the stabilized loess exhibits a comparatively more stable mineral composition. The scanning electron microscope results reveal that hydration products enveloped the soil particles, forming a mesh structure that strengthens the connection between the soil particles. The freeze–thaw damage makes the small and medium pores turn into large pores in loess, while the stabilized loess changes micro and small pores into small and medium pores, with no large pores found. It is feasible to improve loess with the cement composite calcium lignosulfonate, which can provide references for the reinforcement treatment of loess. [ABSTRACT FROM AUTHOR]

The development of a persistent luminescence system with long‐lived phosphorescence and color‐tunable afterglow at room temperature represents a challenge, largely due to the intensive non‐radiative deactivation pathway. In this study, an ultralong‐lived room temperature phosphorescence (RTP) system has been achieved using a hydrogen‐bonding strategy where poly(vinyl alcohol) (PVA) matrices were doped with tryptophan (Trp) derivatives. The PVA film doped with N‐α‐(9‐Fluorenylmethoxycarbonyl)‐L‐tryptophan (Fmoc‐L‐Trp) exhibited a long‐lived phosphorescence emission of up to 3859.70 ms, and a blue afterglow for a duration greater than 34 s, under ambient conditions. The introduction of two other fluorescent dyes (i. e. Rhodamine B and Basicred14) to the PVA film facilitates adjustment to the color of the afterglow from blue to orange, and pink, by a triplet‐to‐singlet Förster‐resonance energy transfer (TS‐FRET) process. These films have been successfully applied in silk‐screen printing and in multicolor afterglow light‐emitting diode (LED) arrays. [ABSTRACT FROM AUTHOR]

Recent research found that stress state and relative density could influence internal instability significantly, however, current internal stability criteria were material-specific, and the effect of stress and density were not accounted for. Furthermore, current criteria were drawn from the dense soils, which could lead to unconservative assessments of loose soils. Because of this, this paper proposes a theoretical internal stability classification chart with considerations of soil density and applied stress. Based on soil fabric and force transmission, a texture triangle chart for three-component mixtures made up of coarse grains, fine grains, and voids was proposed through theoretical analysis of the void filling mechanism in coarse grains. The proposed chart demarcated the boundary between internally stable and unstable granular soils and the boundary between suffusion and suffosion phenomena for internally unstable granular soils. The classification chart relied on identifications of maximum and minimum porosities that coarse grains, fine grains, and coarse–fine mixtures may attain. The internal stability of coarse–fine mixtures with various densification levels could be evaluated by plotting their position in the proposed texture triangle chart. The influence of applied stress on internal stability could also be evaluated in this proposed chart by assessing the changes in volumetric strain. [ABSTRACT FROM AUTHOR]

Objectives: Radiotherapy plays an important role in the treatment of nonsmall‐cell lung cancer (NSCLC). Accurate delineation of tumor is the key to successful radiotherapy. Compared with the commonly used manual delineation ways, which are time‐consuming and laborious, the automatic segmentation methods based on deep learning can greatly improve the treatment efficiency. Methods: In this paper, we introduce an automatic segmentation method by combining coarse and fine segmentations for NSCLC. Coarse segmentation network is the first level, identifing the rough region of the tumor. In this network, according to the tissue structure distribution of the thoracic cavity where tumor is located, we designed a competition method between tumors and organs at risk (OARs), which can increase the proportion of the identified tumor covering the ground truth and reduce false identification. Fine segmentation network is the second level, carrying out precise segmentation on the results of the coarse level. These two networks are independent of each other during training. When they are used, morphological processing of small scale corrosion and large scale expansion is used for the coarse segmentation results, and the outcomes are sent to the fine segmentation part as input, so as to achieve the complementary advantages of the two networks. Results: In the experiment, CT images of 200 patients with NSCLC are used to train the network, and CT images of 60 patients are used to test. Finally, our method produced the Dice similarity coefficient of 0.78 ± 0.10. Conclusions: The experimental results show that the proposed method can accurately segment the tumor with NSCLC, and can also provide support for clinical diagnosis and treatment. [ABSTRACT FROM AUTHOR]

In order to clarify the risk of demolition construction of large-span continuous rigid structure bridge and put forward an intelligent safety assessment method to ensure the safety of demolition construction of the closure segment. Taking a concrete continuous rigid bridge as an example, this paper uses the combination of finite element analysis, theoretical calculation and actual measurement verification to study the influencing parameters and construction safety assessment methods of the long-span continuous rigid bridge in the demolition construction stage of the closure segment. The results show that the parameters that have a great influence on the stress state of box girder and pier during the demolition stage of the closure segment are mainly the self-weight of the structure, tendon prestress state and construction temperature difference. Through the influence envelope analysis of each parameter, it is clear that the ultimate failure mode caused by the most unfavorable parameter combination in the demolition stage of the closure segment is the crushing of the bottom plate of the box girder in the middle span, and the cracking of the piers on the side span at the top and the variable section. In order to further accurately evaluate the construction safety in the demolition stage of the closure segment, based on the long-term down-warping state inversion analysis of the box girder, the identification method of cross-section damage and prestress loss of the box girder and the calculation results of engineering examples are given. Finally, a safety assessment method of the most unfavorable section based on the principle of influence matrix is proposed. Through the analysis of an example, the safety of the closure segment demolition construction is clarified, and the correctness of the analysis is verified by intelligent monitoring means. [ABSTRACT FROM AUTHOR]

This paper investigates the distribution of the sunshine temperature field in bridge structures. To implement thermodynamic boundary conditions on the structure under the influence of sunshine, this study utilized the FILM and DFLUX subroutines provided by ABAQUS. Based on this method, the sunshine temperature field of the concrete box girder of a cable-stayed bridge was analyzed. The results showed that the simulated temperature values were in good agreement with the measured values. The temperature difference between the internal and external surfaces of the box girder under the influence of sunshine was significant, with the maximum negative temperature difference appearing around 6:00 a.m. and the maximum positive temperature difference appearing around 2:00 p.m. The temperature gradient of the box girder section calculated by the method presented a C-shaped distribution pattern, which differs from the double-line distribution pattern specified in the current "General Specifications for Design of Highway Bridges and Culverts" in China (JTG D60-2015). Furthermore, a sensitivity analysis of thermal parameters using the proposed simulation method for the sunshine temperature field of the concrete box girder was conducted, and the results indicated that the solar radiation absorption coefficient had a significant impact on the temperature field. A 30% increase or decrease in the solar radiation absorption coefficient caused the maximum temperature change on the surface of the structure to exceed 10 °C. This paper provides an accurate simulation of the sunshine temperature field of the concrete box girder of a cable-stayed bridge, and the research results are significant for controlling bridge alignment and stress state during the construction period, ensuring the reasonable initial operating state of the bridge, and enhancing the sustainability of the structure. [ABSTRACT FROM AUTHOR]

The combined use of photothermal therapy (PTT) and photodynamic therapy (PDT) could circumvent the drawbacks of each individual therapeutic strategy, resulting in an enhanced antitumor effect. However, the lack of highly effective photo-agents that are irradiation-safe in the biologically transparent window hinder the advancement of phototherapy clinically. Hence, in this study, a charge separation engineering strategy was adopted to fabricate a nanoplatform with heterojunctions, namely, in situ TiO2-loaded MXene (Ti3C2/TiO2 heterojunctions). This nanoplatform exhibited reduced bandgap (1.68 eV), enhanced NIR-II photothermal conversion efficiency (44.98%), and extended absorption edge compared to pristine TiO2 for enhanced photodynamic effect. More importantly, the proliferation of tumor cells could be efficiently inhibited at a 5 mm chicken breast depth after 1064 nm laser irradiation, and the intracellular ROS production significantly increased under 660 nm or even 1064 nm laser irradiation with heterojunctions (HJs) compared with that of TiO2. Moreover, the in vivo data further confirmed that the as-prepared heterojunctions could efficiently eradicate tumors efficiently via improved photothermal effect with NIR-II laser irradiation and upregulated ROS production. Collectively, the reported HJs strategy provides an opportunity for the success of combinational PTT and PDT therapy in tumor treatment. [ABSTRACT FROM AUTHOR]

This paper presents a study on an ancient river-damming landslide in the SE Tibet Plateau, China, with a focus on time-dependent gravitational creep leading to slope failure associated with progressive fragmentation during motion. Field investigation shows that the landslide, with an estimated volume of 4.9 × 107 m3, is a translational toe buckling slide. Outcrops of landslide deposits, buckling, toe shear, residual landslide dam, and lacustrine sediments are distributed at the slope base. The landslide deposits formed a landslide dam over 60 m high and at one time blocked the Jinsha River. Optically stimulated luminescence dating for the lacustrine sediments indicates that the landslide occurred at least 2,600 years ago. To investigate the progressive evolution and failure behavior of the landslide, numerical simulations using the distinct element method are conducted. The results show that the evolution of the landslide could be divided into three stages: a time-dependent gravitational creep process, rapid failure, and granular flow deposition. It probably began as a long-term gravitationally induced buckling of amphibolite rock slabs along a weak interlayer composed of mica schist which was followed by progressive fragmentation during flow-like motion, evolving into a flow-like movement, which deposited sediments in the river valley. According to numerical modeling results, the rapid failure stage lasted 35 s from the onset of sudden failure to final deposition, with an estimated maximum movement rate of 26.8 m/s. The simulated topography is close to the post-landslide topography. Based on field investigation and numerical simulation, it can be found that the mica schist interlayer and bedding planes are responsible for the slope instability, while strong toe erosion caused by the Jinsha River caused the layered rock mass to buckle intensively. Rainfall or an earthquake cannot be ruled out as a potential trigger of the landslide, considering the climate condition and the seismic activity on centennial to millennial timescales in the study area. [ABSTRACT FROM AUTHOR]

Purpose: To introduce an end-to-end automatic segmentation model for organs at risk (OARs) in thoracic CT images based on modified DenseNet, and reduce the workload of radiation oncologists. Materials and Methods: The computed tomography (CT) images of 36 lung cancer patients were included in this study, of which 27 patients' images were randomly selected as the training set, 9 patients' as the testing set. The validation set was generated by cross validation and 6 patients' images were randomly selected from the training set during each epoch as the validation set. The autosegmentation task of the left and right lungs, spinal cord, heart, trachea and esophagus was implemented, and the whole training time was approximately 5 hours. Geometric evaluation metrics including the Dice similarity coefficient (DSC), 95% Hausdorff distance (HD95) and average surface distance (ASD), were used to assess the autosegmentation performance of OARs based on the proposed model and were compared with those based on U-Net as benchmarks. Then, two sets of treatment plans were optimized based on the manually contoured targets and OARs (Plan1), as well as the manually contours targets and the automatically contoured OARs (Plan2). Dosimetric parameters, including Dmax, Dmean and Vx, of OARs were obtained and compared. Results: The DSC, HD95 and ASD of the proposed model were better than those of U-Net. The differences in the DSC of the spinal cord and esophagus, differences in the HD95 of the spinal cord, heart, trachea and esophagus, as well as differences in the ASD of the spinal cord were statistically significant between the two models (P <0.05). The differences in the dose-volume parameters of the two sets of plans were not statistically significant (P >0.05). Moreover, compared with manual segmentation, autosegmentation significantly reduced the contouring time by nearly 40.7% (P <0.05). Conclusions: The bilateral lungs, spinal cord, heart and trachea could be accurately delineated using the proposed model in this study; however, the automatic segmentation effect of the esophagus must still be further improved. The concept of feature map reuse provides a new idea for automatic medical image segmentation. [ABSTRACT FROM AUTHOR]

The debate on whether the creep failure is induced by a stress threshold or a strain threshold is studied on several soils in this paper with a power law model and a normalization curve. The analysis indicates: (a) the creep failure is based on a critical strain, which is obtained with a normalization curve; (b) the time to the creep failure is very long for a low stress level or a low creep exponent; (c) for a given time to the creep failure, the strain threshold could be converted to a stress threshold, and variable stress thresholds will be calculated for different times given to the creep failure; (d) the creep behavior of various materials could be compared with the normalization curve and the power law model. [ABSTRACT FROM AUTHOR]

A peptide/DNA nanocomplex was developed for the targeted delivery of chemotherapeutics and photosensitizers to cancer cells for efficient combination therapy. The chemotherapeutic drug doxorubicin (DOX) and the photosensitizer 5,10,15,20-tetra-(1-methylpyridine-4-yl)-porphyrin (TMPyP4) were physically incorporated by an aptamer (AS1411)-modified tetrahedral DNA nanostructure, where the tetrahedral DNA and aptamer-induced G-quadruplex provide binding sites of DOX and TMPyP4. The co-loaded 3A-TDN/DT displayed a targeted uptake by HeLa cancer cells through the high affinity and specificity between AS1411 and nucleolin, a protein overexpressed on many types of cancer cells. A polycationic polymer, mPEG-PAsp(TECH), was synthesized to complex with the DNA nanostructure to efficiently escape from lysosomes via the proton sponge effect upon the enhanced internalization by tumor cells. Under the irradiation of 660 nm laser light, TMPyP4 induced an upregulation of intracellular reactive oxygen species, which combined with DOX to fulfill the efficient inhibition of HeLa cells. Our study demonstrated a biocompatible peptide/DNA composite nanoplatform for combinational cancer therapy via the targeted delivery of therapeutic agents and efficient lysosomal escape. [ABSTRACT FROM AUTHOR]

Combination therapy is extensively developed for cancer treatment in recent years due to its high efficiency. Herein, we constructed a nanocomposite based on gold nanorods (GNRs) and drug-loaded tetrahedral DNA nanostructures (TDN) for chemo-photothermal combinational therapy. Anti-tumor drug doxorubicin (DOX) was loaded via the insertion within GC base pairs of TDN. The aptamer AS1411 was attached to the apex of TDN (ATDN) to target tumor cells. The DOX-loaded DNA tetrahedron (ATDN-DOX) was compressed by the GNRs coated with PEI (GNRs@ATDN-DOX) to realize the photothermal function and lysosome escape. GNRs under the illumination of 808 nm infrared laser showed high photothermal conversion and stability due to the protection of PEI layer. The drug-loading capacity of ATDN-DOX was as high as 314 DOX molecules in per ATDN. The positive charge of PEI in GNRs@ATDN-DOX nanocomposites was utilized to achieve excellent cell penetration and induce proton sponge effect for lysosomal escape. The nanocomposites presented HeLa and 4T1 cells targeting and resulted in efficient anticancer activity. [ABSTRACT FROM AUTHOR]

In recent years, the main quest of science has been the pioneering of the groundbreaking biomedical strategies needed for achieving a personalized medicine. Ribonucleic acids (RNAs) are outstanding bioactive macromolecules identified as pivotal actors in regulating a wide range of biochemical pathways. The ability to intimately control the cell fate and tissue activities makes RNA‐based drugs the most fascinating family of bioactive agents. However, achieving a widespread application of RNA therapeutics in humans is still a challenging feat, due to both the instability of naked RNA and the presence of biological barriers aimed at hindering the entrance of RNA into cells. Recently, material scientists' enormous efforts have led to the development of various classes of nanostructured carriers customized to overcome these limitations. This work systematically reviews the current advances in developing the next generation of drugs based on nanotechnology‐assisted RNA delivery. The features of the most used RNA molecules are presented, together with the development strategies and properties of nanostructured vehicles. Also provided is an in‐depth overview of various therapeutic applications of the presented systems, including coronavirus disease vaccines and the newest trends in the field. Lastly, emerging challenges and future perspectives for nanotechnology‐mediated RNA therapies are discussed. [ABSTRACT FROM AUTHOR]

This paper proposes a novel high-temperature superconducting stator-excited axial-flux magnetic gear (HTS-SEAFMG) for the high-torque transmitting system. The proposed magnetic gear combines the merits of both HTS-excitation and stator-excitation. By using the HTS-excitation, a high air-gap flux density can be easily obtained, thus achieving the high torque density. The HTS-excitation windings are placed on the stator with a static seal of cooling Dewar which greatly reduces the manufacturing difficulty and the cost of refrigeration system compared with the dynamic seal. Thanks to the stator-excitation pattern, both the high-speed rotor and the low-speed rotor comprise only iron, thus contributing to the high mechanical reliability. The axially sandwich structure can also simplify its assembly in the high torque transmission applications. The dimensional parameter optimization and the electromagnetic performance evaluation are conducted by using the finite element method, respectively. The results show that the torque density of the proposed HTS-SEAFMG can reach 123 kNm/m3. Theoretical analysis and results are both given to verify the feasibility of the proposed HTS magnetic gear design. [ABSTRACT FROM AUTHOR]

The erodibility parameters of barrier dam were an important basis for the evaluation of the outburst flood in the emergency treatment of the dammed lake. The erosion rate was typically modeled with excess shear stress model and Wilson model. However, there is no unified understanding of the range of erodibility parameters. In order to study the range of erodibility parameters of various types of soils and the relationship between the erodibility parameters of two models and soil properties, quickly determine the erodibility parameters of the dam, a database of 279 test results were collected from the literature review as well as by contacting researchers and organizations working on erosion around the world. The samples were classified into coarse-grained and fine-grained soils according to the unified soil classification system. Correlation analysis and regression analysis of the data were used to obtain the relationship between the erodibility parameters and soil properties. Four measures were used to evaluate the statistical significance of the relationship between erodibility parameters and soil parameters for coarse-grained and fine- grained soils: R² MSE Fvalue/Fstatistic and cross-validation. The erodibility parameters obtained from the experimental data were compared with the erodibility parameters predicted by the regression equation, the range of erodibility parameters of different soil and correlation between erosion parameters and soil parameters were obtained. According to the erodibility parameters database, the regression equation of erodibility parameters were obtained through statistical analysis of limited soil parameters and erodibility parameters to quickly predict the erosion rate of the soil. Finally, taking Baige weir plug as an example, according to the erodibility parameter database and statistical relationship established in this study, the erodibility parameters and erosion rate were analyzed rapidly. The research findings can be used to quickly determine the erosion parameters of the dam plug body, and provide help for rapid assessment of the risk of burst flood under emergency conditions. [ABSTRACT FROM AUTHOR]

Sparse canonical correlation analysis (SCCA) is applied to estimate the optimal combination coefficients with sparse properties between two multivariate datasets. It reduces the probability of some unimportant variables and can be interpreted more easily than non-sparse canonical correlation analysis (CCA), especially for high-dimensional datasets. In this paper, a new SCCA algorithm, based on the structure of alternating direction method of multipliers (ADMM), is proposed to solve the ℓ1-penalized SCCA optimization problems. Then, a local subproblem is solved effectively by the variable-separation strategy, with explicit expressions, to update combination coefficients. Finally, several experiments validate that the proposed method is superior than the state-of-the-art SCCA algorithms. [ABSTRACT FROM AUTHOR]

We propose a practical approach to identify plasmonic absorption profile on back focal plane (BFP) of surface plasmon microscopy (SPM). Compared to previous morphology approaches, the proposed one features: i) it is applicable in BFP images with non-concentricity; ii) the algorithm of Fourier Correlation Analysis (FCA) maximizes SPP while minimizes random coherent noises, which makes it extremely suited for BFP images with significant low-quality; (iii) it takes much less time for one identification process and the entire identification can be operated automatically. [ABSTRACT FROM AUTHOR]

Photodynamic therapy would suffer from low efficiency in the cancer treatment process if the reactive oxygen species (ROS) generated from a photosensitizer (PS) were reduced by intracellular glutathione (GSH). To overcome this limitation, in this work, we developed an amphiphilic branched copolymer with pendant vinyl groups, and it self-assembled with chlorin e6 (Ce6) into nanoparticles to fabricate a GSH-reaction response drug delivery system. The vinyl groups in the hydrophobic core of the nanoparticles were reacted with GSH by a "thio–ene" click reaction to release Ce6; simultaneously, the level of GSH decreased for enhanced PDT. Both in vitro and in vivo studies demonstrated that remarkable PDT efficacy for the nanosystem can be achieved. [ABSTRACT FROM AUTHOR]

Background: This study aimed to assess the efficacy and safety of a single‐stage procedure using single‐layer Pelnac and defatted avulsed skin for the management of degloving injuries of the forearm and hand. Methods: This is a prospective study conducted from March 2013 to May 2017. A total of 15 consecutive patients with degloving injuries of the forearm and hand were treated with a single‐stage procedure using single‐layer Pelnac and defatted avulsed skin as a split‐thickness skin graft. Post‐operatively, scheduled follow‐up was conducted. Results: The overall 'take' rate of the Pelnac dermal template and the skin graft was 85–100%. No infections, haematoma or seroma were observed during hospitalization and after discharge. At the final follow‐up, patients' subjective satisfaction with the aesthetic appearance of the grafted areas was, on average, 71.0 (SD 8.0, range 55–92). The Vancouver Scar Scale value was 2.1 (SD 1.8, range 1.0–5.5), representing a good result. The response of 'normal or near normal' to the sensory recovery was obtained for 13 patients and 'slight loss' for two patients. The average Disabilities of the Arm, Shoulder and Hand score was 21.2 (SD 13.5, range 0–53), and most patients (14/15) regained the ability to perform the daily activities without pain or restriction by tissue adhesion. Conclusion: This single‐stage procedure represents an effective technique for the management of degloving injuries of the forearm and hand and should be considered an alternative to other reconstructive procedures. [ABSTRACT FROM AUTHOR]

The centrifugal underwater explosion tests and corresponding numerical simulations were carried out to study the laws of shock wave and bubble pulsation. A semiempirical method to determine JWL state equation parameters was given. The influence on numerical results caused by factors such as state equation of water, boundary condition, and mesh size was analyzed by comparing with the centrifugal underwater explosion test results. The results show that the similarity criterion is also suitable in numerical simulation; the shock wave peak pressure calculated by polynomial state equation is smaller than that of shock state equation. However, the maximum bubble radius and the pulsation period calculated by the two equations are almost the same. The maximum bubble radius is mainly affected by the boundary simulating the test model box, and the pulsation period is mainly affected by the artificial cutoff boundary. With the increase of standoff distance of measuring point, the mesh size required for the numerical calculation decreases; the size of the two-dimensional model is recommended to take 1/30 ∼ 1/10 explosion radius. In three-dimensional models, when mesh size is 2 times larger than explosion radius, the bubble motion change in the second pulsation period is not obvious. When mesh size is smaller than 1 time explosive radius, the full period of bubble pulsation can be well simulated, but calculation errors increase slowly and computation time greatly increases, so the three-dimensional mesh size is suggested to take the charge radius. Shock wave peak pressure is basically unaffected by gravity. As the gravity increases, the bubble maximum radius and the first pulsation period both decrease. [ABSTRACT FROM AUTHOR]

Nontoxic and controllable way to fabricate silk fibroin (SF) gel with high mechanical properties is of critical important to biomaterial in tissue engineering. Electrochemically triggered electrophoretic migration and electric charge of the silk molecules both contributed to SF microspheres and electronic gel (e-gel) formation by sol-gel transition. In this study, a novel silk pH e-gel with higher mechanical property was prepared by combining low-voltage electric fields with isoelectric point (pI) adjustment. This green process was mild and friendly without chemical crosslinker. Compressive modulus of the silk pH e-gel was up to 70 MPa that was significantly higher than that of SF gelation spontaneously. Furthermore, analysis of molecule conformation of the silk pH-e-gel demonstrated that most of random coil structures transformed into α-helix and a little β-sheet structures during this process. The silk pH e-gel was loaded with rhodamine B and showed an obvious sustainable release profile. Accumulation releasing amounts was approximately 60% at day 9. Cytocompatibility of the silk pH-e-gel was evaluated by epithelial cell. The results showed that the gels could support the cell growth and proliferation in vitro. Finally, gel biodegradation was assessed by protease XIV. After biodegradation for 28 days, remaining weight of the gel was about 20.23±2.59 wt%, indicating its good biodegradability. This novel process was established successfully by combining low voltage field with pH-control, which provided an alternative material for regenerative medicine. [ABSTRACT FROM AUTHOR]

Flexible smart materials have attracted a lot of attention in material science, especially in biomaterials and wearable devices. In this study, silk composites with high electroconductivity and biocompatibility were prepared based on a facile slight dissolution technique that reduces weak structures and a nanoscale manipulation of silk fibers, which allows more pyrrole penetration and deposition. The composite resistivity and conductivity are 0.021 ± 0.002 Ω m and 0.47 ± 0.03 S cm−1, respectively. Morphology studies and elemental analysis clearly showed that polypyrrole (PPy) distributed the outer and inner silk fibers homogeneously, which contributed to the improvement of the electroconductivity and electric heating properties. The silk/PPy composite supported PC12 cell growth and development as well. These silk/PPy composites with highlighted features provide favourable candidates for biomedical products and wearable devices. [ABSTRACT FROM AUTHOR]

Surface plasmon microscopy (SPM) provides the capability of measuring surface properties of subnanometer layers within the diffraction limited order. In a typical SPM, small changes correspond to surface plasmons (SPs) absorption profile variations on a reflecting back focal plane (BFP), which can be monitored in real-time. However, the lack of fast and high-accurate identification method on SPs profiles has posed significant challenges on objective-coupled SPM instruments, and also limited their practical applications in fast phenomenon sensing and image batch processing. Here we propose a morphological method to identify the SPs absorption profiles. It can extract the SPs profile information from experimentally recorded BFP images with low quality properly and automatically. Experimental verification and further discussions are included. [ABSTRACT FROM AUTHOR]

Keywords: Critical shear stress; cohesive and noncohesive mixtures; dry density; mud content EN Critical shear stress cohesive and noncohesive mixtures dry density mud content 548 550 3 07/08/20 20200601 NES 200601 The Authors presented an important study on developing a formula for the critical shear stress of sand and mud mixtures, and calibrated the formula with four sets of experimental data from Panagiotopoulos, Voulgaris, and Collins ([6]); Kothyari and Jain ([5]); Ye, Cheng, and Zang ([9]); and Smith, Perkey, and Priestas ([7]). Linear relationships between critical shear and cohesion were found according to regression works for muddy clay and silty clay with the coefficient of determination I R i SP 2 sp equal to 0.929 and 0.983, respectively. The measured dry densities of the gravel and muddy clay mixture at 40% mud content and the gravel and silty clay mixture at 20% mud content have a peak in the variation trend. [Extracted from the article]

Part II of this paper is focused on the dynamic response of a steel plate of the centrifuge model which is fixed on the container. This plate is 5 cm thick, allowing for non-destructive elastic response to all the 19 blasts. Three accelerators and 10 sets of strain gauges are installed on the plate to monitor the acceleration and deformation histories induced by shock waves and bubble oscillations. This article presents the characteristic values measured for shock waves and bubble oscillations response. The detailed information can be found in a database available on the web. In order to obtain the correct acceleration time history, the cut-off frequency of low-pass filtering by Fourier transformation was applied. The results indicated that the acceleration and strain induced by shock wave was nearly unaffected by the increasing gravity, while the effect of gravity has remarkable influence on those induced by bubble oscillation. A preliminary study of comparing the measured dynamic response with numerical simulations has been carried out using ANSYS LS-DYNA. The results captured the dynamic response in terms of characteristics and trends, but deviated in magnitude due the theoretical and technological limitations involved in both the physical and numerical models. It certainly deserves further studies. [ABSTRACT FROM AUTHOR]

Centrifuge is a promising tool for underwater explosion (UNDEX) research as both Mach and Froude similitudes could be satisfied with hyper-gravity in models, which would result in similarities in both shock wave and bubble oscillation. Scaling laws for UNDEX in centrifuge have been proposed based on dimensional analysis. Two dimensionless numbers, i.e., π and π, are used to characterize shock wave and bubble oscillation, respectively. To validate scaling laws, 17 UNDEX tests are designed by varying accelerations or explosive weights and positions in centrifuge. The tests are classified into different groups to validate scaling laws as well as calibrate coefficients in empirical formulae for both shock wave and bubble oscillation. The results show that changes of gravity acceleration or hydrodynamic pressure almost has no influence on shock wave peak pressure and time constant as long as π is constant. The dimensionless bubble period and maximum radius agreed with each other when π is constant. Based on the research, an example is exhibited to suggest method for the computation of initial loading conditions for a submerged obstacle subjected to UNDEX. [ABSTRACT FROM AUTHOR]

Corona current is the key parameter to characterize the corona discharge. Researches on the spectrum characteristics of corona current and the relationships between corona effects are of great significance on optimization design of Ultra High-Voltage Direct Current (UHVDC) transmission line. Basing on the corona current experimental data measured on an actual UHVDC test line, the spectrum characteristics and variation regularity of corona current within the spectrum band of 0.15–4 MHz were studied, and the correlation between energy spectrum of corona current and Radio Interference (RI) under the same conditions was also analyzed in this paper. It was found that variation regularity of logarithmic energy spectrum of corona current was remarkably similar to that of RI within 0.15–4 MHz. Basing on the conclusions above, a formula for estimating the logarithmic energy spectrum of corona current with the maximum nominal surface electric field strength of line was proposed, and the key parameters in the formula were established for a particular typed conductor which was 6-bundled. Those results not only can improve the theoretical understanding of the relationships between corona current and RI, but also provide a new method for estimating the spectrum characteristics of corona current. [ABSTRACT FROM AUTHOR]

The complexity and diversity of noise in corona current measurements of high-voltage direct current (HVdc) transmission lines leads to challenges in estimating corona performance. This paper proposes an offline noise suppression method for HVdc corona current measurements. Given that the corona current and background noise processes coexist within the same frequency band, we develop a novel multifaceted filtering approach for HVdc corona currents. Specifically, a cross correlation function-based center frequency recognition method is presented to provide filter design specification for a multiple notch filter to suppress narrow-band radio interference. To then suppress the residual full-band noise, wavelet denoising techniques with hard and soft thresholds are applied and compared. The proposed noise suppression method is applied to field-measured corona current data from the HVdc Experimental Base in China. We assert that the noise suppression method has versatile implementation and can be readily applied for corona loss estimation of HVdc systems. [ABSTRACT FROM AUTHOR]

A modified smoothed particle hydrodynamics (SPH) method is applied to simulate the dynamic tensile failure of rock-like heterogeneous materials. The material heterogeneities are represented by different mechanical properties with a Weibull distribution at different particles over the specimen. An elasto-plastic-damage model is adopted to simulate material failure. Numerical simulations are performed for three specimens with different degrees of heterogeneity under quasi-static and dynamic loading conditions, respectively. The effects of strength criterion coefficient on the predicted tensile strength are also discussed. Results show that the material heterogeneity has significant effect on the dynamic tensile failure, especially at a higher strain rate loading condition. At a lower strain rate, the failure mode of heterogeneous material is very much similar to that of homogeneous materials. At a higher strain rate, plenty of micro cracks occur forming a failure band in the tension zones. Moreover, the value of strength criterion coefficient has a considerable influence on the tensile strength under a higher loading rate. [ABSTRACT FROM AUTHOR]

In this report we present our study on the assembly process of both the 8 inches substrate assembling as well as the single LCOS module. After the process parameter optimization, 6 um±0.3 um thickness variation were obtained for the 8 inches substrate which is suitable for the WSS based application. Assembly process of single LCOS with 5.8±0.1 um thickness was finally obtained with the optimized process. [ABSTRACT FROM AUTHOR]

In this article, we propose an switchable anti‐spy display device, which has two modes. And we creatively propose to use a brightness enhancement film with polarization function to improve the brightness of the vertical view. In the anti‐spy mode, the display content cannot be clearly recognized by human eyes on the left and right side, but it can be recognized in other directions. In the sharing mode, the display contents can be seen clearly from all perspectives. The anti‐spy display device includes an anti‐spy module and a display module, which is used to display the information, and the anti‐ spy module is used for switching between the sharing mode and the anti‐spy mode. This anti‐spy display device can protect personal privacy and share information with friends or colleagues. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) is an amphiphilic soft material, which can accumulate at the water-air interface. However, GO sheets diffuse slowly in the aqueous phase because of their large size. It is still challenging to form high quality GO films in a controllable and simple way. In this study, we showed that GO sheets can quickly migrate to the water-air interface and form thin films when a suitable amount of acetone is directly mixed with a GO aqueous dispersion. The film formation rate and surface coverage of GO sheets depend on the volume of acetone added, GO dispersion concentration, and formation time. Among several organic solvents, acetone has its advantage for GO film formation owing to its three properties: a nonsolvent to GO aqueous dispersions, miscible with a GO aqueous dispersion, and fast evaporation. Furthermore, we have found that the film formation also is governed by the size of GO sheets and their oxygen content. Although smaller GO sheets could migrate to the water-air interface faster, the overlapping of small GO sheets and the increase in contact resistance is not desirable. A higher oxygen content in GO sheets could also result in smaller GO sheets. Multilayer GO films can be obtained through layer-by-layer dip-coating. These findings open opportunities in developing simple scalable GO film fabrication processes. [ABSTRACT FROM AUTHOR]