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On account of the external disturbances and difficult maneuverability of a hovercraft, this paper devises a safety-guaranteed, robust, nonlinear, path-following control strategy of a hovercraft targeted for unknown dynamics, unavailable velocity, and unknown external ocean disturbances. Firstly, for the sake of accurately observing unavailable lumped disturbances and unavailable velocity measurements, a finite-time extended state observer (FTESO) is proposed. Secondly, a line-of-sight (LOS) guidance law constructed with a bounded-gain-forgetting (BGF) adaptive estimator is devised to follow the desired path while considering external environmental disturbances accurately, in which the tracking errors and the parameter estimation are both proven to be bounded. In addition, for the sake of safety, a safety-guaranteed auxiliary system that can constrain the drift angle during the hovercraft’s navigation is proposed. Thirdly, the robust, nonlinear, path-following controllers achieved high tracking performance with the constructed safety-guaranteed compensation backstepping method. Finally, according to the Lyapunov and homogeneous theories, the observation error can be guaranteed to zero and the tracking error can converge to an arbitrarily small region near zero in finite time. Numerical simulations illustrate the effectiveness for the proposed robust, nonlinear, path-following scheme.

Objectives Thoracic surgery often causes postoperative delirium (POD) in geriatric patients. This study aimed to explore the effect of ultrasound-guided continuous thoracic paravertebral block (UG-TPVB) on POD in geriatric patients undergoing pulmonary resection. Methods Total 128 patients who underwent pulmonary resection were randomly allocated to either the conventional patient-controlled analgesia (PCA) group or the UG-TPVB group (n = 64 per group). The consumption of opioid agents (propofol and remifentanil), postoperative hospital stay, postoperative pulmonary atelectasis, postoperative nausea/vomiting, and postoperative itchiness were recorded. The diagnosis of delirium was dependent on the Nursing Delirium Screening Scale. The postoperative pain was assessed by visual analogue scale (VAS) score. The serum levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α were used to evaluate the postoperative neuroinflammation. Results The consumption of propofol and remifentanil, postoperative hospital stay, postoperative pulmonary atelectasis, postoperative nausea/vomiting, and postoperative itchiness in the UG-TPVB group were lower than that in the PCA group. Compared with the PCA group, the prevalence of POD was decreased in the UG-TPVB group. In addition, use of UG-TPVB not only reduced postoperative pain (VAS score) but also decreased postoperative neuroinflammation compared with PCA in geriatric patients undergoing pulmonary resection. Conclusions This study determined the benefits of UG-TPVB over PCA, providing an effectiveness approach to alleviate POD in geriatric patients undergoing pulmonary resection.

Ultrasound image plays an important role in the diagnosis of thyroid disease. Accurate segmentation and classification of thyroid nodules are challenging due to their heterogeneous appearance. In this paper, we propose an efficient cascaded segmentation framework and a dual-attention ResNet-based classification network to automatically achieve the accurate segmentation and classification of thyroid nodules, respectively. We evaluate our methods on the training dataset TN-SCUI 2020 Challenge. The 5-fold cross validation results demonstrate that the proposed methods achieve average IoU of 81.43% in segmentation task, and average F1 score of 83.22% in classification task. Finally, our method ranks the first place of segmentation task on the test set through the final online verification. The source code of the proposed methods is available at https://github.com/WAMAWAMA/TNSCUI2020-Seg-Rank1st. Electronic supplementary material The online version of this chapter (10.1007/978-3-030-71827-5_14) contains supplementary material, which is available to authorized users.

The shock wave phenomenon has been very common in the high-pressure fuel spray. In this paper, the effect of the shock waves on the spray development and the variations of the flow field parameters were investigated using the Schlieren imaging coupled with a numerical simulation. Results showed that the shock wave contributed to the increase in the spray tip penetration. The mixing characteristics of the spray also improved in the shock-wave state. Numerical simulations were used to investigate the flow characteristics of the shock wave and the effect of the shock wave on the flow field parameters. Results showed that the simulated shock wave characteristic parameters were consistent with the experimental data. In addition, the flow field parameters were affected by the shock wave propagation. The maximum density ratio, pressure ratio and temperature ratio after and before the shock wave are 2.46, 2.01 and 1.15, respectively, under the fuel injection pressure of 320MPa.

Additional file 4: Fig. S4. Loss of either HCR or astrin slightly affects the protein level of CEP72. Parental HeLa cells, HCR-KO HeLa cells, and astrin-KO HeLa cells were analyzed by immunoblotting with CEP72 and beta-actin antibodies. Fig. S5. HCR does not bind to CEP63 and CEP152. HeLa cell lysates were immunoprecipitated with antibodies specific for HCR and negative control IgG. The precipitates were analyzed by immunoblotting with antibodies against CEP63 and CEP152. Fig. S6. Knockdown of astrin and HCR also caused microtubules organization defects in RPE cells. Microtubule regrowth assay of negative control, astrin and HCR siRNA-treated RPE cells co-stained with gamma-tubulin (green), alpha-tubulin (red), and DAPI (blue); scale bars, 10 μm. Fig. S7. Knockdown of astrin and HCR also caused mitotic spindle defects in RPE cells. Negative control, astrin and HCR siRNA-treated HeLa cells were treated with 100 ng/ml nocodazole for 16 hours to be arrested in M-phase and co-stained with gamma-tubulin (green), alpha-tubulin (red), and DAPI (blue); scale bars, 10 μm.

Additional file 9. Verification reports of astrin-KO cell line.

Additional file 5: Fig. S8. Co-localization of HCR with centrin1 and PCM1. HeLa cells transfected with HCR-GFP were co-stain with centrin1 (red) and gamma-tubulin (cyan) and DAPI (blue) or PCM1 (red) and gamma-tubulin (cyan) and DAPI (blue); scale bars, 10 μm. Fig. S9. HCR interacts with CEP131. HeLa cell lysates were immunoprecipitated with antibodies specific for HCR, astrin, or negative control rabbit IgG. The precipitates were analyzed by immunoblotting with antibodies against HCR and CEP131. Fig. S10. HCR did not interact with SKAP, MYCBP and LC8. HeLa cell lysates were immunoprecipitated with astrin, HCR, or control rabbit IgG antibodies and analyzed by western blotting with astrin, HCR, SKAP, MYCBP and LC8 antibodies. Beta actin antibody was used as negative control; HeLa cell lysates were immunoprecipitated with SKAP, MYCBP and LC8, or control rabbit IgG antibodies and analyzed by western blotting with astrin, HCR, SKAP, MYCBP and LC8 antibodies. Beta actin antibody was used as negative control. Fig. S11. HCR interacts with NuMA. mCherry vector alone or HCR-mCherry was transfected into HeLa cells for immunoprecipitation with mCherry antibody. The precipitates were analyzed by immunoblotting with HCR and NuMA antibodies. Fig. S12. HCR co-localizes with astrin and EDC4.HCR-GFP-transfected HeLa cells were treated with arsenite for 30 min and then co-stained with astrin (red) and EDC4 (cyan) for immunofluorescence detection; scale bars, 10 μm. Fig. S13. HCR co-localizes with EDC4 in mitosis. Negative control, HCR siRNA-treated HeLa cells were co-stained with HCR (red) and EDC4 (green); scale bars, 10 μm. Fig. S14. HCR was closely related to tumorigenesis. The dataset was from TCGA ( portal.gdc.cancer.gov ) and analyzed by TIMER 2.0 ( cistrome.org ).

BackgroundIt has been suggested that Helicobacter pylori (H. pylori) infection is associated with hypergastrinemia and proliferation of colorectal mucosa via direct stimulation, dysbiosis of the gut microbiome, and changes in the gut microbiome, all of which may lead to the formation of colorectal polyps. However, the consensus remains lacking regarding whether H. pylori infection is independently associated with colorectal polyps and whether the association differs according to histological type of colorectal polyps. To summarize the current evidence regarding the relationship between H. pylori infection and colorectal polyps, we conducted a meta-analysis of related observational studies according to the histological types of colorectal polyps.MethodsObservational studies investigating the association between H. pylori infection and colorectal polyps using multivariate analyses were included by search of PubMed, Embase, and Web of Science. A random-effects model was adopted to combine the results.ResultsSeventeen studies that include 322,395 participants were analyzed. It was shown that H. pylori infection was independently associated with overall colorectal polyps (odds ratio [OR]: 1.67, 95% CI: 1.24–2.24, p < 0.001; I2 = 73%). According to the histological type of colorectal polyps, H. pylori infection was independently associated with adenomatous polyps (APs; OR: 1.71, 95% CI: 1.47–1.99, p < 0.001; I2 = 86%), advanced APs (OR: 2.06, 95% CI: 1.56–2.73, p < 0.001; I2 = 0%), and hyperplastic polyps (HPs; OR: 1.54, 95% CI: 1.02–2.30, p = 0.04; I2 = 78%). Evidence based on only one study showed that H. pylori infection was not associated with sessile serrated polyps (SSPs; OR: 1.00, 95% CI: 0.93–1.07, p = 0.99).ConclusionsCurrent evidence from case-control and cross-sectional studies suggested that H. pylori infection was independently associated with colorectal APs, advanced APs, and HPs, but not with SSPs. These findings suggested H. pylori infection may be a possible risk factor of colorectal polyp, which is important for the prevention of colorectal polyp in the adult population.

Additional file 3: Fig. S3. Apoptosis or cycle changes in astrin-KO cells and identification of astrin-KO cell line. (A) Parental, astrin-KO and HCR-KO HeLa cells were analyzed with astrin, HCR, cyclin B1 and Cleaved PARP antibodies. HeLa cells treated with DMSO, Paclitaxel, Bafilomycin and MG132 were analyzed with Cleaved PARP and HCR antibodies. (B) Parental and astrin-KO HeLa cells were immunoblotted with an astrin antibody.

Additional file 1: Fig. S1. Repeated verification of the interaction between HCR and astrin. (A) Astrin Co-IP HCR and CEP72 and HCR Co-IP astrin and CEP72. HeLa cell lysates were immunoprecipitated with astrin, HCR, or control rabbit IgG antibodies and analyzed by western blotting with anti-astrin, anti-HCR antibodies. Anti-GM130 and anti-beta actin antibodies were used as negative control. The blotting of astrin, HCR and GM130 antibodies were incubated on the same membrane by repeatedly washing the membrane with antibody removal solution to increase comparability. (B) HCR interacts with astrin in HEK293 and U2OS cells. mCherry vector alone or HCR-mCherry in conjunction with the GFP-astrin plasmid were transfected into HEK293 cells for immunoprecipitation using an mCherry antibody. The eluted proteins were analyzed with mCherry and GFP antibodies. HCR-mCherry plasmid-transfected HEK293 cells were immunoprecipitated with astrin antibody or negative control rabbit IgG. The precipitates were analyzed with mCherry and astrin antibodies. U2OS cell lysates were immunoprecipitated with an HCR antibody or negative control rabbit IgG. The precipitates were analyzed with antibodies against HCR and astrin.

Additional file 2: Fig. S2. Identification of HCR-GFP stable Cell Line and Localization of HCR in cells. (A) Identification of HCR-KO HeLa cell line and stably expressing HCR-GFP cell line. Parental HeLa cells, HCR-KO HeLa cells, HCR-KO cells transfected with HCR-GFP, and stably transfected HCR-GFP HCR-KO cells were immunoblotted with an HCR antibody. (B) Co-localization of astrin-CC2 and HCR-CC3. HeLa cells transfected with astrin-CC2-myc and HCR-GFP or astrin-CC2-myc and HCR-CC3-GFP were co-stained with myc (red) and gamma-tubulin (cyan); scale bars, 10 μm. (C) Co-localization of HCR with alpha-tubulin. Mitotic HeLa cells stained with an alpha-tubulin antibody (green), HCR antibody (red), and DAPI (blue) for nuclear staining (left panel) or stained with anti-alpha-tubulin (green), anti-astrin (red), and DAPI (blue) (right panel); scale bars, 10 μm. (D) Identification of antibody staining to HCR. Negative control, HCR siRNA-treated HeLa cells were co-stained with HCR (red) and alpha-tubulin (green); scale bars, 10 μm. (E) The effect of Nocodazole on HCR is dose-dependent and recoverable. HeLa cells were treated with 1μM, 0.75μM, 0.5μM Nocodazole for 5 hours or treated with 1μM Nocodazole for 5hours then released from Nocodazole for 30 min, 1 hour, 2 hours, then co-stained with HCR (red) and gamma-tubulin (green). (F) Knockdown of HCR does not affect PCM1 localization. Negative control, HCR siRNA-treated HeLa cells were co-stained with HCR (red) and PCM1 (green); scale bars, 10 μm.

In this article, we design the first full software/ hardware stack, called Uni-OPU , for an efficient uniform hardware acceleration of different types of transposed convolutional (TCONV) networks and conventional convolutional (CONV) networks. Specifically, a software compiler is provided to transform the computation of various TCONV, i.e., zero-inserting-based TCONV (zero-TCONV), nearest-neighbor resizing-based TCONV (NN-TCONV), and CONV layers into the same pattern. The compiler conducts the following optimizations: 1) eliminating up to 98.4% of operations in TCONV by making use of the fixed pattern of TCONV upsampling; 2) decomposing and reformulating TCONV and CONV into streaming parallel vector multiplication with a uniform address generation scheme and data flow pattern; and 3) efficient scheduling and instruction compilation to map networks onto a hardware processor. An instruction-based hardware acceleration processor is developed to efficiently speedup our uniform computation pattern with throughput up to 2.35 TOPS for the TCONV layer, consuming only 2.89 W dynamic power. We evaluate Uni-OPU on a benchmark set composed of six TCONV networks from different application fields. Extensive experimental results indicate that Uni-OPU is able to gain $1.45 \times $ to $3.68 \times $ superior power efficiency compared with state-of-the-art zero-TCONV accelerators. High acceleration performance is also achieved on NN-TCONV networks, the acceleration of which have not been explored before. In summary, we observe $1.90 \times $ and $1.63 \times $ latency reduction, as well as $15.04 \times $ and $12.43 \times $ higher power efficiency on zero-TCONV and NN-TCONV networks compared with Titan Xp GPU on average. To the best of our knowledge, ours is the first in-depth study to completely unify the computation process of zero-TCONV, NN-TCONV, and CONV layers.

Peroxisomes are essential organelles that play important roles in a variety of biological processes in eukaryotic cells. To understand the synthesis of peroxisomes comprehensively, we identified the gene FgPEX22-like, encoding FgPEX22-like, a peroxin, in Fusarium graminearum. Our results showed that although FgPEX22-like was notably different from other peroxins (PEX) in Saccharomyces cerevisiae, it contained a predicted PEX4-binding site and interacted with FgPEX4 as a rivet protein of FgPEX4. To functionally characterize the roles of FgPEX22-like in F. graminearum, we performed homologous recombination to construct a deletion mutant (ΔPEX22-like). Analysis of the mutant showed that FgPEX22-like was essential for sexual and asexual reproduction, fatty acid utilization, pathogenicity, and production of the mycotoxin deoxynivalenol. Deletion of FgPEX22-like also led to increased production of lipid droplets and decreased elimination of reactive oxygen species. In addition, FgPEX22-like was required for the biogenesis of Woronin bodies. Taken together, our data demonstrate that FgPEX22-like is a peroxin in F. graminearum that interacts with PEX4 by anchoring PEX4 at the peroxisomal membrane and contributes to the peroxisome function in F. graminearum.

All-season warming is assumed to advance snowmelt and delay snow accumulation; additionally, coupled with warming-induced drought stress, all-season warming could extend both the beginning and the end of the fire season. Using fire data updated for 1968–2018, we found an asymmetrical expansion of the lightning fire season in the boreal forest of Northeast China. Lightning fires have not advanced into the early fire season (May–June) but have largely extended into the snowless late fire season (July–September) since the late 1990s (mean end Julian date delayed by 51.1 days for 1998–2018 compared with 1968–1997, p < 0.001). Despite significant warming, the Julian days of snowmelt have changed only slightly, which has prohibited the fire season from advancing into early spring. The expansion of lightning fires into July–September was associated with a warming-induced significant increase in evapotranspiration and a decrease in soil/fuel moisture.

The present work investigates the effects of microwave-assisted annealing on the granulation and photocatalytic performance of anodic TiO2 nanotubes. The results indicate that although microwave-assisted heating can transform the amorphous TiO2 nanotubes into completely anatase one within 5min, it brings the collapse and granulation of TiO2 nanotubes, which weaken their photocatalytic activity. Meanwhile, the detachment and evolution of F- rich layer to a layer of TiO2 membrane with rounding-off surface, and the stripping of TiO2 nanotube bottom from its body are also observed.

In order to improve the comprehensive mechanical properties of the commonly used ductile iron QT400-18, the microstructure of the ductile iron in the cast state was improved by optimizing the heat treatment process, thereby improving its comprehensive mechanical properties. The mechanical properties of the heat-treated samples at different annealing rates were tested, and the microstructures of the samples were observed. Furthermore, the influence of different heat treatment processes on the mechanical properties was analyzed. The results indicated that the mechanical properties and tissue properties of ductile iron QT400-18 were significantly improved after heat treatment. With the increase of annealing rate, the spheroidization effect, low temperature impact toughness and elongation showed a tendency to increase first and then decrease, while the strength and hardness decrease. The microstructure and mechanical properties of ductile cast iron were optimal at annealing rate of 70 °C/h. According to the national standards and actual requirements of subway products, the annealing rate of 110 °C/h or 150 °C/h could also be chosen to improve production efficiency on the premise of meeting the performance requirements.

In this paper, we study the problem of multiple stochastic agents interacting in a dynamic game scenario with continuous state and action spaces. We define a new notion of stochastic Nash equilibrium for boundedly rational agents, which we call the Entropic Cost Equilibrium (ECE). We show that ECE is a natural extension to multiple agents of Maximum Entropy optimality for single agents. We solve both the "forward" and "inverse" problems for the multi-agent ECE game. For the forward problem, we provide a Riccati algorithm to compute closed-form ECE feedback policies for the agents, which are exact in the Linear-Quadratic-Gaussian case. We give an iterative variant to find locally ECE feedback policies for the nonlinear case. For the inverse problem, we present an algorithm to infer the cost functions of the multiple interacting agents given noisy, boundedly rational input and state trajectory examples from agents acting in an ECE. The effectiveness of our algorithms is demonstrated in a simulated multi-agent collision avoidance scenario, and with data from the INTERACTION traffic dataset. In both cases, we show that, by taking into account the agents' game theoretic interactions using our algorithm, a more accurate model of agents' costs can be learned, compared with standard inverse optimal control methods.

Low precision data representation is important to reduce storage size and memory access for convolutional neural networks (CNNs). Yet, existing methods have two major limitations: (1) requiring re-training to maintain accuracy for deep CNNs, and (2) needing 16-bit floating-point or 8-bit fixed-point for a good accuracy. In this paper, we propose a low precision (8-bit) floating-point (LPFP) quantization method for FPGA-based acceleration to overcome the above limitations. Without any re-training, LPFP finds an optimal 8-bit data representation with negligible top-1/top-5 accuracy loss (within 0.5%/0.3% in our experiments, respectively, and significantly better than existing methods for deep CNNs). Furthermore, we implement one 8-bit LPFP multiplication by one 4-bit multiply-adder (MAC) and one 3-bit adder, and therefore implement four 8-bit LPFP multiplications using one DSP slice of Xilinx Kintex 7 family (KC705 in this paper) while one DSP can implement only two 8-bit fixed-point multiplications. Experiments on six typical CNNs for inference show that on average, we improve throughput by 64.5x over Intel i9 CPU and by 1.5x over existing FPGA accelerators. Particularly for VGG16 and YOLO, compared to six recent FPGA accelerators, we improve average throughput by 3.5x and 27.5x and improve average throughput per DSP by 4.1x and 5x, respectively. To the best of our knowledge, this is the first in-depth study to simplify one multiplication for CNN inference to one 4-bit MAC and implement four multiplications within one DSP while maintaining comparable accuracy without any re-training., 11 pages, 11 figures, submitted to TCAD. arXiv admin note: text overlap with arXiv:2003.02628

Low precision data representation is important to reduce storage size and memory access for convolutional neural networks (CNNs). Yet, existing methods have two major limitations: (1) requiring re-training to maintain accuracy for deep CNNs, and (2) needing 16-bit floating point or 8-bit fixed point for a good accuracy. In this paper, we propose a low precision (8-bit) floating point (LPFP) quantization method for FPGA-based acceleration to overcome the above limitations. Without any re-training, LPFP finds an optimal 8-bit data representation with negligible top-1/top-5 accuracy loss (within 0.5%/0.3% in our experiments, respectively, and significantly better than existing methods for deep CNNs). Furthermore, we implement one 8-bit LPFP multiplication by one 4-bit multiply-adder (MAC) and one 3-bit adder, and therefore implement four 8-bit LPFP multiplications using one DSP slice of Xilinx Kintex-7 family (KC705 in this paper) while one DSP can implement only two 8-bit fixed point multiplications. Experiments on six typical CNNs for inference show that on average, we improve throughput by 64.5× over Intel i9 CPU and by 1.5× over existing FPGA accelerators. Particularly for VGG16 and YOLO, compared to six recent FPGA accelerators, we improve average throughput by 3.5× and 27.5× and improve average throughput per DSP by 4.1× and 5×, respectively. To the best of our knowledge, this is the first in-depth study to simplify one multiplication for CNN inference to one 4-bit MAC and implement four multiplications within one DSP while maintaining comparable accuracy without any re-training.

In the pump-free lithium bromide absorption refrigeration system, the two-phase flow pattern in the lift tube of the bubble pump has a decisive influence on the lift performance of the bubble pump. The heat and mass transfer between two phase interfaces can be accurately described by mesoscale method,In order to explore the working mechanism of lithium bromide solution bubble pump, the improved lattice Boltzmann method combine lattice Boltzmann heat transfer model are adopted to simulate The rising process and coalescence behavior of multiple bubbles in lithium bromide solution in a vertical bubble pump with gas-liquid density ratio of 2778. The density field and velocity vector distribution of multiple bubbles under different initial conditions were obtained. The critical coalescence distance of water vapor in lithium bromide solution with double bubbles and 3 bubbles is obtained. The motion process of 4 bubbles with different initial settings is simulated. The influence of the number of bubbles on the critical coalescence distance is discussed. That results provide a great reference value for the study of the transition mechanism between flow patterns.

The recovery of Cr(VI) from vanadium precipitated solution obtained by adding Ca(OH)2 into chromium-containing vanadate solution and ball milling was investigated by precipitation with PbSO4. It was found that Cr can be effectively precipitated from the solution by PbSO4. The precipitate is mixture of PbSO4 and PbCrO4.PbO. The concentration of Cr remained in the solution decreases from 2.360 g/L to 0.002 g/L by adding PbSO4 into vanadium precipitated solution according to PbSO4/Cr molar ratio 3.0 under pH 11.5 and stirring for 120 min at 30 °C. After filtration, the precipitates were leached in H2SO4-Na2SO4 system solution to obtain Na2Cr2O7 solution and the filtrate can be reused to leach the precipitate contain PbSO4 and PbCrO4.PbO.

Convolutional neural networks (CNNs) achieve state-of-the-art performance at the cost of becoming deeper and larger. Although quantization (both fixed-point and floating-point) has proven effective for reducing storage and memory access, two challenges -- 1) accuracy loss caused by quantization without calibration, fine-tuning or re-training for deep CNNs and 2) hardware inefficiency caused by floating-point quantization -- prevent processors from completely leveraging the benefits. In this paper, we propose a low-precision floating-point quantization oriented processor, named Phoenix, to address the above challenges. We primarily have three key observations: 1) 8-bit floating-point quantization incurs less error than 8-bit fixed-point quantization; 2) without using any calibration, fine-tuning or re-training techniques, normalization before quantization further reduces accuracy degradation; 3) 8-bit floating-point multiplier achieves higher hardware efficiency than 8-bit fixed-point multiplier if the full-precision product is applied. Based on these key observations, we propose a normalization-oriented 8-bit floating-point quantization method to reduce storage and memory access with negligible accuracy loss (within 0.5%/0.3% for top-1/top-5 accuracy, respectively). We further design a hardware processor to address the hardware inefficiency caused by floating-point multiplier. Compared with a state-of-the-art accelerator, Phoenix is 3.32x and 7.45x better in performance with the same core area for AlexNet and VGG16, respectively., Comment: 14 pages, 18 figures, submitted to TVLSI

Insertion of dead time in space vector pulse width modulation (SVPWM) causes phase voltage and current distortion or even zero-current clamping phenomenon, degrading the control performance of ac induction motor. In addition, analysis of distortion becomes more complicated due to the existence of parasitic capacitance in power switching device of voltage source inverter (VSI). This paper tries to make clear that how the parasitic capacitance influences VSI's output independently. First, an equivalent circuit of VSI containing parasitic capacitance is constructed. On that basis, mathematical expression of phase voltage distortion is derived from Kirchhoff's voltage law, Kirchhoff's current law, and charge and discharge characteristics of capacitance. Moreover, through the division of multiple zero-crossing regions in one phase current period, the difficulty of obtaining specific phase voltage error expressions is overcome. Second, to figure out the effect of parasitic capacitance, it is theoretically discussed in detail that how parasitic capacitances of different values affect phase voltage, current distortion, and zero-current clamping phenomenon. At last, simulations and experiments are carried out in which VSI with different parasitic capacitances is constructed by paralleling additional capacitors and with phase voltage feedback methods, the theoretical analysis can be verified.

Daxing’anling is a key region for forest fire prevention in China. Assessing changes in fire risk in the future under multiple climatic scenarios will contribute to our understanding of the influences of climate change for the region and provide a reference for applying adaptive measures for fire management. This study analyzed the changes in fire weather indices and the fire season under four climate scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5) for 2021–2050 using data from five global climate models together with observation data. The results showed that the analog data could project the average state of the climate for a given period but were not effective for simulating extreme weather conditions. Compared with the baseline period (1971–2000), the period 2021–2050 was predicted to have an increase in average temperature of 2.02–2.65 °C and in annual precipitation 25.4–40.3 mm, while the fire weather index (FWI) was predicted to increase by 6.2–11.2% and seasonal severity rating (SSR) by 5.5–17.2%. The DMC (Duff moisture code), ISI (initial spread index), BUI (build-up index), FWI and SSR were predicted to increase significantly under scenarios RCP4.5, RCP6.0, and RCP8.5. Furthermore, days with high or higher fire danger rating were predicted to be prolonged by 3–6 days, with the change in the southern region being greater under scenarios RCP4.5, RCP6.0, and RCP8.5.

Safia Naz,1,* Mingyu Wang,1,* Yuning Han,1 Bin Hu,1 Liping Teng,2 Juan Zhou,1 Huijie Zhang,1 Jinghua Chen11Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, People’s Republic of China; 2Wuxi School of Medicine, Jiangnan University, Wuxi, People’s Republic of China*These authors contributed equally tothis workBackground: Drug delivery systems (DDS) capable of targeting both cell and organelle levels are highly desirable for effective cancer therapy. In this study, we developed a novel enzyme-responsive, multistage-targeted anticancer DDS based on mesoporous silica nanoparticles (MSNs), which possessed both CD44-targeting and mitochondrial-targeting properties.Materials and methods: Triphenylphosphine (TPP), a mitochondria-targeting compound, was grafted onto the surface of MSNs firstly. Then, Doxorubicin (Dox) was encapsulated into the pore of MSNs, followed by capping with tumor-targeting molecules hyaluronic acid (HA) through electrostatic interactions to form the final product consist of Dox loaded, TPP attached, HA capped mesoporous silica nanoparticles (MSN-DPH).Results: Our results suggested that MSN-DPH was preferentially taken up by cancer cells via CD44 receptor-mediated endocytosis. Moreover, MSN-DPH mainly accumulated in mitochondria owing to the mitochondrial-targeting ability of TPP. Degradation of HA by overexpressed HAase facilitated the release of Dox in cancer cells. Thus, MSN-DPH efficiently killed the cancer cells while exhibited much lower cytotoxicity to normal cells.Conclusion: This study demonstrates a promising multistage-targeted DDS for cancer chemotherapy.Keywords: mesoporous silica nanoparticles, drug delivery, enzyme-responsive, multistage-targeting, cancer therapy &nbsp

Matrine is an alkaloid extracted from the leguminous plant Sophora flavescens. Matrine has clinical effects in the treatment of tumors, including those in lung cancer, nasopharyngeal cancer and liver cancer. However, the effect of matrine on follicular thyroid cancer has not been reported. The aim of the present study was to investigate the effect of matrine on follicular thyroid cancer and its potential mechanism. FTC-133 follicular thyroid cancer cells were treated with different concentrations of matrine, and an MTT assay showed that matrine inhibited the growth of FTC-133 cells in a dose- and time-dependent manner with an IC50 value of 154.8 µM. Cell apoptosis was analyzed by flow cytometry and the results showed that matrine effectively induced the apoptosis of FTC-133 cells. The expression level of microRNA (miR)-21 was analyzed by reverse transcription-quantitative PCR (RT-qPCR) analysis, and the mRNA and protein expression levels of PTEN, Akt and phosphorylated (p)-Akt were detected by RT-qPCR analysis and western blotting, respectively. The expression of miR-21 was significantly downregulated, PTEN was upregulated at the mRNA and protein expression levels, and p-Akt was downregulated in the FTC-133 cells. The effects of miR-21 mimics and miR-21 inhibitor on the expression of miR-21, PTEN and Akt in FTC-133 cells, and the effect of miR-21 mimics/matrine on the expression of PTEN were also investigated. The results of the present study suggested that matrine inhibited the growth and induced apoptosis of FTC-133 cells via the miR-21/PTEN/Akt signaling pathway.

In order to study the symbiotic medium of two petroleum degrading bacteria, Cycloclasticus sp. and Alcanivorax sp. Single factor experiment, uniform design and neural network combined with genetic algorithm were used to optimize medium components. The concentration of carbon source (diesel) is 0.5%, the concentration of nitrogen source (NH4)2SO4 is 8 g/L, phosphorus source is KH2PO4:Na2HPO4 mol ratio 3:1, yeast powder concentration is 0.03 g/L, culture time is 3D, culture temperature is 20, pH = 7.6, loading amount is 30 mL, inoculation amount is 1.5%, and rocking bed speed is 150 rpm. The test results were consistent with expectations. The degradation rate reached 89.80% after optimization and 14.4% higher than the original 78.50%. Through the optimization of the symbiotic medium, the culture medium suitable for the symbiosis of bacteria group is obtained, which shows that the neural network and genetic algorithm have remarkable superiority in the optimization of culture medium.

Oil spill identification is important for marine environmental protection. In this paper, the artificial neural networks (ANNs) model is built to analysis FTIR fingerprint for identifying oil spill sources. The BP neural network model was trained with the specific data from literature, and this kind of spill oil ANNs was used to predicate the unknown samples successfully. The identification accuracy rate of the ANNs was 96.5%. This method can be used to analyze the infrared fingerprint of oil and identify the source of oil spill at sea. When predicting 12 unknown samples, 67, 69 and 71 samples deviate, but the accuracy of prediction is not affected. The different training methods have great influence on the network output. According to the results, the ratio conjugate gradient algorithm and the Levenberg-Marquardt algorithm training network model have the highest accuracy, the ANNs can be used for various different species as well as the weathered oil samples.

Extracts are important components of fuels. Fatty-extracts with high heating value (HV) are hypothesized by researchers as positively related to the HV of fuels. The Soxhlet extractor is typically used to extract fatty-extracts but it has shortcomings, including long processing time (8–10 h) and the requirement for large amounts of organic solvent. Supercritical extraction is an alternate and useful technique for extraction of natural products. However, published studies rarely discuss the relationship between extracts and HV. In this study, we assessed the supercritical extracts (SuE) of forest fuels in the Great Xing’an Mountains. Our results indicated that the optimum conditions for extraction of SuEs were 40–60 mesh, 40–50 MPa, 45 °C, 80 min and a CO2 flow rate of 1.5–2.0 dm3/min. The Soxhlet extracts contents and the SuE contents were all related to HV. However, R 2 of the coniferous samples (0.8499) and needle samples (0.9722) demonstrated that the correlation between HV and the SuE content was closer. We conclude that supercritical fatty-extracts provide a useful index of the HV of fuels, especially coniferous fuels. SuE data can be used in fire management, for example to estimate the rate of fire spread or fire intensity.

With more and more stringent environmental requirements that go into effect, the automotive industry is moving away from R134a. All major automotive manufacturers are considering next generation refrigerants, but there is still no agreement on the final choice. As for electric vehicles, the choice of refrigerant to replace R134a is even more complex, since a refrigerant’s heating capacity and efficiency should be considered with the gradual adoption of heat pump technology for cabin heating. In order to help select the best refrigerant for electric vehicle HVAC systems, in this paper a comprehensive assessment has been conducted for seven refrigerants: R134a, R152a, R1234yf, R290, R410A, R32, and R744 (CO2). TEWI method is used for evaluating the total global warming impact for each refrigerant, in which both the cabin cooling and heating are considered in the calculation of indirect emission from energy consumption. For cabin heating, heat pump is used to its maximal available capacity, whereas PTC heater is used for supplemental heating. TEWI assessment results show that R290 refrigerant generates the lowest amount of equivalent CO2 emission whereas R744 gives off the highest amount. When considering comprehensively safety, heating capacity and global warming impact, R32 is found to be a very promising heat pump refrigerant.

Oil spill identification is an important means of investigation of oil spill through analysis and comparison of suspicious oil spill source. This paper proposed a GC/MS fingerprint fitting method based on genetic algorithm (GA) to identify the source of oil spill. In this method, dominant characteristic peaks were selected from the 3d fingerprint of the standard and stored in the prevailing characteristic fingerprint database (dominant database). Recessive characteristic peaks were screened out from the periphery of the dominant characteristic peaks of the sample and stored in the recessive characteristic fingerprint database (recessive database). Then a set of characteristic peaks was selected from the dominant library by GA to correct the characteristic peaks in the samples and automatically identify the similarity between the standard and the samples. Simulation calculation compared with experimental analysis results showed that the method to build a detailed identification of oil spill fingerprint was accurate and reliable. The method to identify the fingerprint peak can be clearly and accurately reflect the properties of the sample, which can be used for rapid automatic calculation of chromatographic fingerprint similarity, so as to strengthen sea spill accident discriminant scientific theory in identification, traceability and the application of legal liability.

With the rising prevalence of industrial Internet of Things (IoT) devices, it has become more important to ensure that IoT devices are secure. A method that attackers use to gain access to the IoT devices is to spoof themselves as the IoT server. Traditional authentication methods need a lot of memory resources, which is unable to meet the needs of lightweight IoT devices. The idea of the new authentication protocol is to use the historical data exchanged between an IoT device (verifier) and a server (prover) as a second authentication factor, in addition to the conventional factor of a shared secret key. The new authentication method needs more memory resources of server instead of IoT devices, which is what people want. However, the historical data authentication factor is considered a big dataset and the retrieve of selected pieces of data from a large data pool usually encounters long latency if the algorithm and implementation are not well optimized. To reduce latency, three methods are proposed in this dissertation. After presenting the new authentication method using historical data and optimizing it, a real system is implemented. Because the IoT devices are normally unable to verify the legality of the server, BeagleBone Black (BBB) (a kind of single board computer) is used to verify. Thus, the communication between the IoT device and BBB and between BBB and server are key problems. A structure named “bridge” is built and in order to insert verifier process, ip_queue in Linux is adopted. Thus, an optimized authentication process using historical data can be run in this system. Master of Science (Electronics)

In three-dimensional topological insulators (TIs), the nontrivial topology in their electronic bands casts a gapless state on their solid surfaces, using which dissipationless TI edge devices based on the quantum anomalous Hall (QAH) effect and quantum Hall (QH) effect have been demonstrated. Practical TI devices present a pair of parallel-transport topological surface states (TSSs) on their top and bottom surfaces. However, due to the no-go theorem, the two TSSs always appear as a pair and are expected to quantize synchronously. Quantized transport of a separate Dirac channel is still desirable, but has never been observed in graphene even after intense investigation over a period of 13 years, with the potential aim of half-QHE. By depositing Co atomic clusters, we achieved stepwise quantization of the top and bottom surfaces in BiSbTeSe2 (BSTS) TI devices. Renormalization group flow diagrams13, 22 (RGFDs) reveal two sets of converging points (CVPs) in the (Gxy, Gxx) space, where the top surface travels along an anomalous quantization trajectory while the bottom surface retains 1/2 e2/h. This results from delayed Landau-level (LL) hybridization (DLLH) due to coupling between Co clusters and TSS Fermions.

An all-digital coherent-like binary frequency shift keying (BFSK) demodulation based on the use of a multi-bit shift register, two multi-bit XOR gates and a mean value filter is presented. The demodulator is fabricated in SMIC 65-nm CMOS process with a die area of 0.015 mm 2 . The demodulator consumes 1.44 mW with 1.2 V of voltage supply and 32 MHz of sample clock. The measured bit error ratio (BER) performance is better than that of other non-coherent demodulators. The proposed demodulator exhibits better performance in terms of composite indicator compared to other demodulators. Another advantage of the all-digital demodulator defined using Verilog HDL is that it can also be implemented on Field Programmable Gate Array (FPGA) platform rapidly to recover FSK signals with different carrier frequencies and data rates. These results make the all-digital demodulator suitable for the application in communication and consumer electronics.

Spatial information related to the occurrence of fire is the basis for risk reduction efforts. Satellite data on the occurrence of hotspots and statistical data were used to analyse the distribution characteristics of wildfires for 2008–2012. The results show that most hotspots were caused by prescribed and agricultural burning and forest fires. The size of 99% of forest fires was less than 100 ha, and the average annual burned area was 124,192 ha. Most of the forest fires occurred in the spring (accounting for 83%), with March having the highest rate (60.0%). Forest fires were mainly distributed in the south and southwest regions of China. In total, 72.2% of the forest fires occurred in humid region of the medium temperate zone, and 54% occurred in regions with altitudes lower than 500 m. Forest fires often occurred in sparsely populated areas (

Fire is a major disturbance factor in boreal forest ecosystems. Research on fire regimes is important for understanding fire disturbance and for taking a scientific approach to fire management in the Daxing’anling region. Fire scars in Daxing’anling were extracted from NOAA/MODIS satellite remote sensing data for the period 1987-2010. The paper analyzed the spatial-temporal characteristics of the fire scars and the relationship between burned areas and forest fire danger indexes. The results showed that the annual burned area had a significant correlation with fire danger indexes. The average annual burned area was 192,200 ha during 1987-2010, and the fire scars were mainly distributed in the northern and eastern parts of the region. The fire cycle for the Daxing’anling region was 75 years. The fire scars were mainly located in coniferous and broadleaf mixed forests and larch forest. Mild, moderate and severe burned areas accounted for 45.3%, 37.0% and 17.7% of the total burned area, respectively.

The urban thermal environment is an important element for the urban ecological environment,urban climate and urban disasters.This paper selected MOD11A2,the MODIS LST night data to study the thermal environment evolution in Beijing,Shanghai and Guangzhou,which are the three major cities of China in the past decade.Three methods have been applied in the paper,Landscape centroid evolution,Landscape pattern index and spatial autocorrelation.Three main conclusions have been drawn as follows.Firstly the thermal landscape distributions in the three cities have moved from the suburb to the downtown.And the evolution trend of the thermal landscape is changed from the low temperature region,sub-middle temperature region to middle temperature region,sub-high temperature region and high temperature region.Secondly,among these five types of thermal landscape,the middle temperature region is the most prevalent.The urban thermal landscape fragmentation was highest in Shanghai among the three cities,and sub-middle and high temperature region has the highest fragmentation.The urban thermal landscape dispersion was highest in Beijing,and the dispersion of low and high temperature region was higher than the other types of thermal landscapes.Thirdly,thermal environment spatial autocorrelation analysis showed that the high-high temperature zones were adjacent,low-low temperature areas were adjacent,which are the main types in the temperature spatial agglomeration.And for Beijing and Guangzhou city,the high-high temperature zone located in the south of the city,the low-low temperature region located in the north.While,the spatial autocorrelation distribution of LST in Shanghai is more complicated.The distribution areas of high-high temperature varied among the three cities in the past decade.In Beijing,the distribution area increased shortly after decreasing,and in Guangzhou,the distribution area continued to decline,which preliminary reflects the heat island effect problem aggravated in Beijing,while weakened in Shanghai and Guangzhou. Through comparisons and analysis,the paper has provided a reference for urban planning and urban living environment improvements,but there are still some inadequacies to be further studied.Firstly,this study only selected the January night LST data in the three cities.Because the time factors,such as season,daytime and nocturne,will affect the urban heat environment pattern,the comprehensiveness of the thermal environment pattern changes need to be improved.In addition,the paper only selected the data in the period of three years,the evolution regulation of the urban thermal environment pattern is not precise.Secondly,the landscape of urban heat environment were impacted by many factors,including the pattern of landuse,urban surface construction,weather conditions,terrain,anthropogenic heat emissions factors and so on.The analysis between the urban heat environment and impact factors will help reveal the mechanism of urban heat environment and which will be studied further.

SUMMARY Essential oil of fuels is closely linked with the behavior of forest fires, especially high intensity fires and eruptive fires. It is assumed that the potential reason is the large quantities of flammable gases released from essential oil-rich fuels before pyrolysis in fire environment. However, few studies have been carried out on the hypothesis. The purpose of the present study is to investigate the emissions from essential oil-rich fuels. The fuels were collected from three coniferous species. In the experiment, needles and twigs were heated in a vacuum oven at 200 °C, and the emissions within 15 min had been sampled using Tenax tubes. Gas chromatography–mass spectrometry served as an analytical instrument. The results showed that the emissions contained high proportion of monoterpenes, such as α-pinene, camphene, β-pinene, 3-carene, and d-limonene. The monoterpene emissions from heated needles and twigs of Pinus pumila, Larix gmelinii, and Pinus sylvestris were 61.221, 49.606, and 37.853 µg g−1 dry weight (needles), and 211.727, 139.957, and 121.505 µg g−1 dry weight (twigs), respectively. Statistical analyses showed the significant differences not only among species but also between needles and twigs. Copyright © 2012 John Wiley & Sons, Ltd.

To study the optimal performance characteristics and maximize the removal efficiency of contaminants by the constructed floating islands (CFIs), four kinds of parallel pilot-scale CFIs with different structures were set up outdoors to treat eutrophic water for approximately 6 months. The contribution of artificial aeration to nutrient removal on the basis of gas-water ratios was investigated, and the influences of the structure and temperature were evaluated simultaneously. It was noted that the nutrient removal rate of the multi-medium CFI was greater than those of others. In the four kinds of units, aeration could significantly increase the nutrient removal efficiency, and a gas-water ratio of 10 was adequate for the relatively high removal of nutrients. Using the aforementioned gas-water ratio of 10 and a hydraulic residence time (HRT) of 2 days, the mean removal efficiencies of the multi-medium CFI for NH3-N and total phosphorus were 71.7% and 63.6%, respectively-approximately twice as great as those in the non-aerated system. Furthermore, temperature was an important factor for nutrient removal in the multi-medium CFI. With the water temperature of >13 degrees C and the HRT of 2.5 days, the mean removal efficiencies for NH3-N and total phosphorus were 87.6% and 83.5%, respectively, whereas the removal efficiency decreased significantly when the temperature was lower than 13 degrees C.

Climate warming has a rapid and far-reaching impact on forest fire management in the boreal forests of China. Regional climate model outputs and the Canadian Forest Fire Weather Index (FWI) System were used to analyze changes to fire danger and the fire season for future periods under IPCC Special Report on Emission Scenarios (SRES) A2 and B2, and the data will guide future fire management planning. We used regional climate in China (1961–1990) as our validation data, and the period (1991–2100) was modeled under SRES A2 and B2 through the weather simulated by the regional climate model system (PRECIS). Meteorological data and fire danger were interpolated to 1 km2 by using ANUSPLIN software. The average FWI value for future spring fire seasons under Scenarios A2 and B2 shows an increase over most of the region. Compared with the baseline, FWI averages of spring fire season will increase by −0.40, 0.26 and 1.32 under Scenario A2, and increase by 0.60, 1.54 and 2.56 under Scenario B2 in 2020s, 2050s and 2080s, respectively. FWI averages of autumn fire season also show an increase over most of the region. FWI values increase more for Scenario B2 than for Scenario A2 in the same periods, particularly during the 2050s and 2080s. Average future FWI values will increase under both scenarios for autumn fire season. The potential burned areas are expected to increase by 10% and 18% in spring for 2080s under Scenario A2 and B2, respectively. Fire season will be prolonged by 21 and 26 days under Scenarios A2 and B2 in 2080s respectively.

The average temperature of northeastern China is expected to increase 2.22 and 2.55°C under two scenarios selected from the Intergovernmental Panel on Climate Change (IPCC), i.e., A2 and B2, during the 2040s (2041–2050), which will have an impact on fire activities in those areas. We calculated the output of regional climate models, using the Canadian Forest Fire Weather Index (FWI) on a scale of 50 km × 50 km. Meteorological data and fire weather index were interpolated to a scale of 1 km × 1 km by using ANUSPLIN software. The results show that the model of Providing Regional Climate for Impacts Studies (PRECIS) had the ability to provide good temperature and precipitation estimates of the study area in the baseline period, by simulation. In the 2040s the mean FWI values of the study area will increase during most of the fire seasons under both selected scenarios, compared with the baseline period. Under scenario B2 the peak fire season will appear in advance. The changes of FWI ratio (2×CO2/1×CO2) show that the potential burned areas will increase 20% under scenario B2 and lightly increase under scenario A2 in 2040s. The days of high, very high and extreme fire danger classes will add 5 and 18 d under scenarios A2 and B2, respectively. It suggests adapting the climate change through improving fuel management and enhancing the fighting abilities.

A study was conducted to explore the mechanism that emissions of volatile organic compounds (VOC) from heated needles and twigs (200°C, within 15 min) of Pinus pumila affect fire behaviours using the technology of Thermal Desorption — Gas Chromatography — Mass Spectrometry (TD-GC-MS). The results indicated that the main components of VOC from heated needles and twigs are terpenoids. Most of these terpenoids are monoterpenes. Terpenoids account for 72.93% for the needles and 92.40% for the twigs of the total VOC, and their emission ratios are 61.200 μg·g−1 and 217.060 μg·g−1 respectively. Heated twigs can emit more terpenoids than heated needles because twigs had more volatile oils than needles. In actual fires, these large amounts of terpenoid emissions, especially the monoterpene emissions, have strong effects on fire behaviors that are not only in the initial stage but also in the fast propagation stage of fires. These flammable gases are capable of causing violent combustion and creating crown fires. In addition, if these gases accumulate in an uneven geographical area, there will be a possible for eruptive fires and/or fires flashover to occur.