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We have studied the two phases of the molecular crystal acetylene, C2H2, using calculations of the lattice dynamics by Density Functional Theory methods.

The phase-selective controlled synthesis of Cs4PbBr6 and CsPbBr3 nanocrystals was realized by adjusting the dosage of oleic acid.

The topological Weyl semimetals with peculiar band structure exhibit novel nonlinear optical enhancement phenomena even for light at optical wavelengths. While many intriguing nonlinear optical effects were constantly uncovered in type-I semimetals, few experimental works focused on basic nonlinear optical properties in type-II Weyl semimetals. Here we perform a fundamental static and time-resolved second harmonic generation (SHG) on the three dimensional Type-II Weyl semimetal candidate $\beta$-WP$_2$. Although $\beta$-WP$_2$ exhibits extremely high conductivity and an extraordinarily large mean free path, the second harmonic generation is unscreened by conduction electrons, we observed rather strong SHG response compared to non-topological polar metals and archetypal ferroelectric insulators. Additionally, our time-resolved SHG experiment traces ultrafast symmetry switching and reveals that polar metal $\beta$-WP$_2$ tends to form inversion symmetric metastable state after photo-excitation. Intense femtosecond laser pulse could optically drive symmetry switching and tune nonlinear optical response on ultrafast timescales although the interlayer coupling of $\beta$-WP$_2$ is very strong. Our work is illuminating for the polar metal nonlinear optics and potential ultrafast topological optoelectronic applications., Comment: 8 pages, 5 figures

The past decade has seen a significantly increased use of high-power ultrafast lasers in micromachining applications. With the continual increase of the laser power for ultrafast lasers, an increase in the ablation rate has been brought about. However, it also created some negative effects, such as the heat-affected zone (HAZ) and thermal damages, which hardly occur at lower power. This issue was reported in the literature but has not been systematically addressed by previous research. This paper presents a systematic study on using the burst mode ablation to limit the HAZ while maintaining a high ablation efficiency using a high-power industrial picosecond laser with burst fluence larger than 10 J/cm2. An extended three-dimensional two-temperature model (3D-TTM) was employed to study the mechanism of the HAZ development and to predict the ablation efficiency with experimental validation. The essentiality of including the lattice heat conduction to predict accurate HAZ was discussed. The effect of the number of pulses per burst and pulse to pulse separation time was investigated. The optimal number of pulses per burst was obtained by using the 3D-TTM for copper and stainless steel. The 3D-TTM suggested that by using the optimal number of pulses per burst, a maximum reduction of 77% and 61% in HAZ could be achieved for copper and stainless steel respectively. And the corresponding ablation efficiency will be increased by 24% and 163% for copper and stainless steel at the same time. This study showed that burst mode laser machining at high fluence is an effective way of increasing efficiency while limiting the HAZ.

The primary and secondary catastrophes of emergencies, as well as their comprehensive disasters, add a significant deal of complexity and risk to the grassroots emergency response system’s creation. The completeness of the emergency response system development is significantly related to improving the basic capacity of grassroots emergency security. The weight comparison calculation and analysis of the links at all levels in the emergency response system is carried out using the hierarchical analysis method based on the basic experience of current domestic related fields for the construction of the emergency response process system, and the results of the relative importance ranking of indicators are obtained, and this is used to provide emergency response and emergency management decision makers with emergent information.

Rice false smut (RFS), caused by Ustilaginoidea virens, is an important fungal disease of rice. In China, Methyl Benzimidazole Carbamates (MBCs), including carbendazim, are common fungicides used to control RFS and other rice diseases. In this study, resistance of U. virens to carbendazim was monitored for three consecutive years during 2018 to 2020. A total of 321 U. virens isolates collected from Jiangsu Province of China were tested for their sensitivity to carbendazim on PSA. The concentration at which mycelial growth is inhibited by 50% (EC50) of the carbendazim-sensitive isolates was 0.11 to 1.38 µg/mL, with a mean EC50 value of 0.66 μg/mL. High level of resistance to carbendazim was detected in 14 out of 321 isolates. The resistance was stable but associated with a fitness penalty. There was a statistically significant and moderate negative correlation (r= −0.74, p < 0.001) in sensitivity between carbendazim and diethofencarb. Analysis of the U. virens genome revealed two potential MBC targets, Uvβ1Tub and Uvβ2Tub, that putatively encode β-tubulin gene. The two β-tubulin genes in U. virens share 78% amino acid sequence identity, but their function in MBC sensitivity has been unclear. Both genes were identified and sequenced from U. virens sensitive and resistant isolates. It is known that mutations in the β2-tubulin gene have been shown to confer resistance to carbendazim in other fungi. However, no mutation was found in the Uvβ2Tub gene in either resistant or sensitive isolates. Variations including point mutations, non-sense mutations, codon mutations, and frameshift mutations were found in the Uvβ1Tub gene from the 14 carbendazim-resistant isolates, which have not been reported in other fungi before. Thus, these results indicated that variations of Uvβ1Tub result in the resistance to carbendazim in field isolates of Ustilaginoidea virens.

Rice false smut (RFS), caused by

Rice false smut (RFS) caused by

Rice blast caused by Magnaporthe oryzae is one of the most destructive fungal diseases of rice worldwide. Stimulatory effects of low doses of fungicides on pathogens are closely relevant to disease management. In the present study, in potato dextrose agar (PDA) amended with carbendazim at a dose range from 0.003 to 0.3 μg/mL, stimulatory effects on the mycelial growth of three isolates sensitive to carbendazim were tested. Carbendazim at concentrations from 0.003 to 0.1 µg/mL showed stimulatory effects on mycelial growth of isolates Guy11 and H08-1a, while carbendazim at concentrations from 0.003 to 0.03 µg/mL stimulated the growth of isolate P131. The maximum stimulation magnitudes were 11.84% for the three isolates tested. Mycelial colonies grown on PDA amended with different concentrations of carbendazim were incubated at 28 °C in darkness for 7 days as the pretreatment. Pretreatment mycelia were inoculated on fresh fungicide-free PDA and subsequent mycelia growth stimulations were still observed, and the maximum stimulation magnitudes were 9.15% for the three isolates tested. Pretreatment mycelia did not significantly change the tolerance to H2O2 and NaCl, except that the tolerance to H2O2 was increased significantly (p < 0.05) when the carbendazim was at 0.3 µg/mL. After five generations of mycelial transference on fungicide-free PDA, the transgenerational hormesis of mycelial were exhibited when transferred onto PDA supplemented with carbendazim at 0.3 µg/mL, and the maximum percent stimulation was 51.28%. The time course of infection indicated that the visible initial necrotic symptoms could be detected at 2 DPI on leaves treated with carbendazim at 0.03 µg/mL, whereas no necrotic symptom could be discerned for the control. Statistical results of lesion area and lesion type at 7 DPI showed that there was a significant stimulation (p < 0.05) on aggressiveness of M. oryzae isolate Guy11 on detached rice leaves at 0.03 µg/mL carbendazim. These results will advance our understanding of hormetic effects of fungicides and provide valuable information for judicious application of fungicides.

Continuous emergence of persistent organic pollutants perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in various water bodies around the world poses a serious threat to the global ecosystem. The exploration of advanced detection/removal techniques to monitor/treat such type of toxicants is urgently required. Herein, we unveiled a donor-acceptor type conjugated polymer PF-DBT-Im as a first-of-its-kind ratiometric fluorescent probe for visual, amplified, and specific monitoring of PFOA and PFOS with ultra-low detection limits of 6.12 nM (PFOA) and 14.3 nM (PFOS), respectively. PF-DBT-Im undergoes strong aggregation after binding with PFOA/PFOS as evident by transmission electron microscopy, zeta potential measurements, and dynamic light scattering studies. This promotes interchain Förster resonance energy transfer process to endorse an obvious emission color change from blue-to-magenta under ultraviolet lamp excitation. Consequently, a smartphone-integrated portable device is fabricated for realizing rapid and on-site detection of PFOA/PFOS. Besides, a new class of magnetic adsorbent Fe

Rice blast caused by

BackgroundThis study aimed to observe the correlation between renal cortical blood perfusion (CBP) parameters and BP response in patients with severe renal artery stenosis (RAS) who underwent stenting.MethodsThis was a single-center retrospective cohort study. A total of 164 patients with unilateral severe RAS after successful percutaneous transluminal renal artery stenting in Beijing Hospital from October 2017 to December 2020 were included. According to the results of BP evaluated at 12 months, all patients were divided into the BP response group (n = 98) and BP nonresponse group (n = 66). The baseline clinical and imaging characteristics and follow-up data about 24 h ABPM and CBP were recorded and analyzed. Pearson correlation analysis was used to evaluate the relationship between CBP parameters and 24 h average SBP. Univariate and multivariate logistic regression analysis was used to evaluate the risk factors for BP response.ResultsAmong 164 patients with severe RAS, there were 100 males (61.0%), aged 37–75 years, with an average of 56.8 ± 18.4 years, and average artery stenosis of 84.0 ± 12.5%. The BP nonresponse patients had a longer duration of hypertension, more current smoking subjects and diabetic patients, lower eGFR, increased number of hypertensive agents, and rate of insulin compared with the BP response group (P < 0.05). After PTRAS, patients in the BP response group were associated with significantly lower BP and improved CPB, characterized by increased levels of maximum intensity (IMAX), area under ascending curve (AUC1), area under the descending curve (AUC2), shortened rising time (RT), mean transit time (mTT), and prolonged time to peak intensity (TTP; P < 0.05). However, the BP nonresponse group was only associated with significantly reduced RT (P < 0.05) compared with baseline data. During an average follow-up of 11.5 ± 1.7 months, the BP response group was associated with significantly lower levels of SBP, DBP, 24 h average SBP, and 24 h average DBP compared with the nonresponse group (P < 0.05). Pearson correlation analysis showed that the the pre-operative CBP parameters, including IMAX (r = 0.317), RT (r = 0.249), AUC1 (r = 0.614), AUC2 (r = 0.558), and postoperative CBP parameters, including RT (r = 0.283), AUC1 (r = 0.659), and AUC2 (r = 0.674) were significantly positively correlated with the 24 h average SBP, while the postoperative TTP (r = −0.413) and mTT (r = −0.472) were negatively correlated with 24 h average SBP (P < 0.05). Multivariate Logistic regression analysis found that diabetes (OR = 1.294), NT-proBNP (OR = 1.395), number of antihypertensive agents (OR = 2.135), pre-operation IMAX (OR = 1.534), post-operation AUC2 (OR = 2.417), and baseline dDBP (OR = 2.038) were related factors for BP response (all P < 0.05).ConclusionPatients in the BP nonresponse group often have diabetes, a longer duration of hypertension, significantly reduced glomerular filtration rate, and heavier renal artery stenosis. CBP parameters are closely related to 24 h average SBP, and pre-operation IMAX and post-operation AUC2 are markers for a positive BP response.

With the advent of 5G era, the electronic and electrical industries are in increasingly urgent demand for flexible materials with high thermal conductivity coefficients (λ). In this paper, alumina (Al2O3) was chemically grafted to the surface of boron nitride nanosheets (BNNS) to prepare hetero-structured thermally conductive fillers (BNNS@Al2O3), and two-component room temperature vulcanized silicone rubber (RTV-2SR) was used as the polymer matrix. Then BNNS@Al2O3/RTV-2SR flexible thermally conductive and electrically insulating composite films were prepared by shear-coating. Results of X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and scanning electron microscope (SEM) showed that the BNNS@Al2O3 hetero-structured thermally conductive fillers with “point-plane” structure were successfully prepared. The BNNS@Al2O3 hetero-structured thermally conductive fillers successfully achieved the synergy of Al2O3 and BNNS and had more significant improvement on λ than single Al2O3, single BNNS, and simply blending BNNS/Al2O3. When the amount of BNNS@Al2O3 was 30 wt% (BNNS/Al2O3, 1:1, wt:wt), the in-plane λ (λ∥) and through-plane λ (λ⊥) of the BNNS@Al2O3/RTV-2SR thermally conductive composite film reached 2.86 W/mK and 0.89 W/mK, 2.8 times λ∥ (1.01 W/mK) and 4.2 times λ⊥ (0.21 W/mK) pure RTV-2SR film, also higher than those of BNNS/RTV-2SR (with single BNNS, λ∥ = 2.46 W/mK, λ⊥ = 0.76 W/mK), Al2O3/RTV-2SR (with single Al2O3, λ∥ = 1.62 W/mK, λ⊥ = 0.49 W/mK), and (BNNS/Al2O3)/RTV-2SR (with simply blending BNNS/Al2O3, 1:1, wt:wt, λ∥ = 2.04 W/mK, λ⊥ = 0.62 W/mK) thermally conductive composite films with the same fillers amount. Meanwhile, the prepared BNNS@Al2O3/RTV-2SR thermally conductive composite film obtained excellent mechanical properties, electrical insulation properties, and thermal properties. Its tensile strength, elongation at break, hardness, dielectric constant (e), dielectric loss (tanδ), volume resistivity (ρv), glass transition temperature (Tg), and heat resistance index temperature (THRI), respectively, reached 0.84 MPa, 175%, 27 HA, 3.89, 0.0088, 5.76 × 1011 Ω·cm, − 40.1 °C and 185.3 °C. This work can provide a new idea for the preparation of hetero-structured thermally conductive fillers and flexible thermally conductive and electrically insulating composite films. Schematic diagrams for hetero-structured BNNS@Al2O3 fillers, BNNS@Al2O3/RTV-2SR thermally conductive composite films and corresponding thermal conduction mechanism.

Exploring the spin degree of freedom in electronic transport of carbon-based materials, such as carbon nanotubes (CNTs), is of interest from the point of view of materials and applications. However...

Detection of arterial stiffness is an important method to predict the occurrence of hypertension complications and to screen patients with high cardiovascular risk. In order to predict the damage of AASI to the renal function of patients with essential hypertension, the prediction of AASI based on stepwise Regression equation scanning for renal function damage in patients with essential hypertension is proposed. Measure the 24 h ambulatory blood pressure of the selected subjects, establish a linear Regression equation scanning, and calculate the slope of the straight line, and finally, the slope is AASI. According to the quartiles, AASI is divided into four parts: group I < 0.53 ( n = 49 ); 0.53 ≤ group II < 0.60 ( n = 51 ); 0.60 ≤ group III < 0.69 ( n = 48 ); group IV ≥ 0.69 ( n = 44 ). Experiment result shows the following: with the increase of AASI, cystatin (CysC) also increased significantly, while CysC-eGFR decreased significantly ( P < 0.05 ). Compared with groups I, II, and III, Scr and CysC in group IV increased ( P < 0.05 ), and Ccr, CysC-eGFR, and (CKD-EPI)-eGFR all decreased ( P < 0.05 ). AASI is positively correlated with CysC performance, and the correlation coefficient r is 0.637. It is negatively correlated with Ccr performance, and r is -0.361. It is negatively correlated with CysC-eGFR, and r is -0.698. And it is negatively correlated with (CKD-EPI)-eGFR, and r is -0.331. Age and 24 h PP also showed an increasing trend with the increase of AASI, and it suggests that age may be an influencing factor that promotes kidney damage caused by hypertension; it also suggests that AASI can be used as a new indicator of arterial compliance; AASI is linearly related to various indicators of renal damage and can be used as a predictive indicator of renal damage caused by essential hypertension; cystatin C and the estimated glomerular filtration rate CysC-eGFR based on cystatin C are better than other indicators reflecting glomerular filtration rate, more sensitively assess the degree of early renal damage. Obesity may also be a factor that promotes kidney damage caused by hypertension.

The orientational disorder in crystalline sulfur hexafluoride, SF6, has been studied using a combination of neutron total scattering and the reverse Monte Carlo method. Analysis of the atomic configurations has shown the extent of the disorder through the evaluation of the S–F bond orientational distribution function, consistent with, but improving upon, the results of earlier neutron powder diffraction data. The correlations between orientations of neighbouring molecules have been studied through analysis of the distributions of F–F distances, showing that nearest-neighbour F–F close contacts are avoided, consistent with previous molecular dynamics simulation results. The results present a new case study of the application of neutron total scattering and the reverse Monte Carlo methods for the study of orientational disorder, where in this instance the disorder arises from orientational frustration rather than from a mismatch of molecular and site symmetries.

Edwardsiella piscicida is one of the important pathogens in aquaculture, which takes huge losses to the economic benefits of turbot industry. Thus, a simple, rapid and accurate diagnostic assay of E. piscicida becomes an urgent need. In the present study, a detection method of E. piscicida based on recombinase polymerase amplification combined with lateral flow strip (RPA-LF) was established. The RPA-LF assay targeted E. piscicida evpP gene and could detect as low as 10 fg DNA of E. piscicida, which was approximately 1000 times more sensitive than conventional PCR assay. Meanwhile, the RPA-LF assay showed no cross-reactivity with DNA from other major bacterial pathogens in aquaculture. Besides, to improve the convenience of RPA-LF assay, a rapid on-the-spot sample preparation using nucleic acid extraction by cellulose dipsticks was established. Results indicated that bacteria could be detected as low as 1 copy and completed within 30 min. Moreover, this modified RPA-LF assay could be used to monitor E. piscicida infection in turbot industry.

This study aimed to elaborate on the role of salt concentration on pickled Brassica napus leaf and stem (BLS); it also contributed to the development of low-salt and healthy Brassica napus products in the harvest period. Five sets of pickled BLS samples were prepared, and the physicochemical parameters, free amino acids (FAAs), and the volatile flavor components (VFCs) were analyzed after fermentation. Results showed that some antioxidants, FAAs, and VFCs underwent dynamic changes during fermentation. Nitrite increased with an increase in the salt concentration used for fermentation. Pickled BLS contained a wide range of FAAs; a total of 23 were detected, which might be used as a source of amino acid supplementation. The VFCs were analyzed via headspace solid-phase micro-extraction (HS-SPME) combined with gas chromatography and mass spectrometry (GC-MS). A total of 51 VFCs were tentatively identified. The contribution to flavor could be expressed by the relative odor activity value (ROAV). Salt is one of the important factors affecting the quality of vegetable fermentation. Therefore, for large-scale pickled BLS production, a key issue is to balance the low salt concentration and high fermentation quality. Under the action of salt and microorganisms, the fresh BLS fermented via dry pickling, which not only improved its FAAs and VFCs, endowed the production with a unique flavor, but also prolonged the shelf life.

Rice false smut (RFS) caused by Ustilaginoidea virens has been one of the most severe rice diseases. Fungicide-based chemical control is a significant measure to control RFS. In the sensitivity determination of quinone outside inhibitor (QoI) fungicide in vitro, salicylhydroxamic acid (SHAM) has been commonly added to artificial culture media in order to inhibit alternative oxidase of phytopathogenic fungi. However, some studies showed that artificial media should not include SHAM due to its toxicity. Whether SHAM should be added in the assay of U. virens sensitivity to QoI fungicide remains unknown. In this study, two appropriate media, potato sucrose agar (PSA) and minimal medium (MM), were selected to test SHAM toxicity and sensitivity of U. virens to azoxystrobin and pyraclostrobin. The mycelial growth and sensitivity to azoxystrobin and pyraclostrobin had no significant difference between on PSA and MM. SHAM could significantly inhibit mycelial growth, conidial germination, peroxidase (POD) and esterase activity of U. virens. Average effective concentration for inhibiting 50% (EC50) values of SHAM against mycelial growth of ten U. virens were 27.41 and 12.75 μg/mL on PSA and MM, respectively. The EC50 values of SHAM against conidial germination of isolates HWD and JS60 were 70.36 and 44.69 μg/mL, respectively. SHAM at 30 μg/mL significantly inhibited POD and esterase activity of isolates HWD and JS60, and even SHAM at 10 μg/mL significantly inhibited POD activity of isolate HWD. In addition, SHAM significantly reduced EC50 values and EC90 values of azoxystrobin and pyraclostrobin on both PSA and MM. Even in the presence of SHAM at 10 μg/mL, average EC50 values of ten U. virens isolates for azoxystrobin decreased 1.7-fold on PSA and 4.8-fold on MM, and for pyraclostrobin that decreased 2.8-fold on PSA and 4.8-fold on MM. Therefore, these results suggest that SHAM should not be included in artificial media in the assay of U. virens sensitivity to QoI fungicides.

Lin28 is a pluripotency factor that regulates cancer cell stem-like phenotypes to promote cancer development and therapy-resistant tumor progression. It acts through its cold shock domain and zinc knuckle domain (ZKD) to interact with the Let-7 pre-microRNA and block Let-7 biosynthesis. Chemical inhibition of Lin28 from interacting with Let-7 presents a therapeutic strategy for cancer therapy. Herein, we present the computer-aided development of small molecules by in silico screening 18 million compounds from the ZINC20 library, followed by the biological validation of 163 predicted compounds to confirm 15 new Lin28 inhibitors. We report three lead compounds, Ln7, Ln15, and Ln115, that target the ZKD of both Lin28A and Lin28B isoforms and block Lin28 from binding Let-7. They restore Let-7 expression and suppress tumor oncogenes such as SOX2 in cancer cells and show strong inhibitory effects on cancer cell stem-like phenotypes. However, minimal impacts of these compounds were observed on Lin28-negative cells, confirming the on-target effects of these compounds. We conclude from this study the discovery of several new Lin28 inhibitors as promising candidate compounds that warrant further drug development into potential anticancer therapies.

We report a study of the orientational order and phase transitions in crystalline deuterated methane, carried out using neutron total scattering and the reverse Monte Carlo method. The resultant atomic configurations are consistent with the average structures obtained from Rietveld refinement of the powder diffraction data, but additionally enable us to determine the C-D bond orientational distribution functions (ODF) for the disordered molecules in the high-temperature phase, and for both ordered and disordered molecules in the intermediate-temperature phase. We show that this approach gives more accurate information than can been obtained from fitting a bond ODF to diffraction data. Given the resurgence of interest in orientationally-disordered crystals, we argue that the approach of total scattering with the RMC method provides a unique quantification of orientational order and disorder.

Objectives To investigate the feasibility of using near-infrared spectroscopy for rapid determination of main organic acids in Ginkgo biloba leaf extract (EGBL). Methods Main organic acids in EGBL were assayed using the HPLC method. Critical factors of the chromatographic separation were optimized by a novel analytical quality by design approach. Partial least squares-discriminant analysis (PLS-DA) was performed to screen the marker components, and principal component analysis (PCA) was utilized to distinguish the different samples. Then, spectral quantification potential was investigated using PLS and support vector machine (SVM) approaches. For modelling, different spectral preprocessing and wavelength selection methods were systematically compared. Key findings It was found that quinic acid, protocatechuic acid and 6-hydroxykynurenic acid were identified as possible index components. PLS-DA based on contents and PCA based on near-infrared spectra can both effectively distinguish the different EGBL samples. The calibration models with wonderful prediction performance can be both developed by the PLS and SVM algorithms. Conclusions NIR spectroscopy combined with chemometrics can realize the rapid and non-destructive qualitative and quantitative analysis of EGBL. The proposed method may be applied to quality control of EGBL and other natural products in commercial use.

The objective of this work is to construct a nanosuspension drug delivery system of probucol, a BCS II drug, in order to improve its dissolution and oral bioavailability. The wet milling procedure using planetary beads-milling equipment was utilized to grind the raw probucol to ultrafine nanoparticle/nanocrystal aqueous suspension that was further solidified by freeze-drying process. Cellulose derivatives of different substitution groups and molecular weights, including HPMC, HPC, and MC, were evaluated as the primary stabilizer of probucol nanosuspension. Ternary stabilizers system composed of a primary stabilizer (cellulose derivative, i.e. HPC), a nonionic surfactant (Pluronic® F68), and an anionic surfactant (SDS) was employed to obtain probucol nanosuspension of finer particle size and enhanced dissolution in aqueous media. The probucol nanosuspension with good physical stability showed no obvious change of particle size even after storing over 7 d at 4 °C or 25 °C. The solidified probucol nanosuspension with trehalose as the cryoprotectant showed the highest dissolution rate (> 60% at 2 h) compared to other cryoprotectant. The in vivo pharmacokinetic evaluation indicated about 15-folds higher AUC value of the probucol nanosuspension compared to that of coarse probucol suspension after oral administration to rats. The probucol nanosuspension prepared by wet-milling and ternary stabilizers system may find wide applications for improving the dissolution and oral absorption of water-insoluble drugs., Graphical abstract The wet milling procedure using planetary beads-milling equipment was utilized to grind the raw probucol to ultrafine nanoparticle/nanocrystal aqueous suspension that was further solidified by freeze-drying process. Image, graphical abstract

Poly(3-hexylthiophene), (P3HT), is widely used in organic semiconductor applications. Time of Flight measurements on P3HT displayed three distinct hole transport pathways with corresponding mobilities above 10−4, between 10−5 and 10−4 and below 10−5 cm2V−1s−1 over a range of sample thickness (1.1 μm–4.2 μm), and electric field (2.4 MVm−1 to 37.7 MVm−1). The space-charge limited current (Mott-Gurney) device mobility was in agreement with that obtained for the fastest route (10−4 cm2V−1s−1). The transport pathways were distinguished using a dispersive transport plot of reciprocal transit time versus electric field to thickness ratio and are described by single (pseudo dispersion) parameters: α t 1 = 0.97 , α t 2 = 0.73 and α t 3 = 0.62 . The P3HT displayed 3 M mass peaks obtained by Gel Permeation Chromatography, which are the most likely cause of the three pathways. The dispersive transport analysis used here offers clearer distinction between pathways than Poole-Frenkel plots and offers a full mobility description, including the dependence on sample thickness, making it suitable for general application.

Measurement-device-independent quantum key distribution (MDIQKD) protocol has been proven to be unaffected by all hacking attacks and ensures the security of information theory even when the performance of single-photon detectors is not ideal. Single-mode fiber and free space are the two main channel choices in MDIQKD experiments. In this paper, we present a voltage pulse generator (VPG) for the MDIQKD, focusing on the realization of pulse control using a wideband amplifier that offers a high dynamic range, on the prevention of waveform distortion and insufficient drive capacity. In order to implement MDIQKD experiments, either fiber channel or free-space channel, a pulse modulation module is needed to modulate the wide pulse chopping, decoy state, normalization, phase encoding, and time encoding. The test results of the joint test with fiber channel MDIQKD show that the quantum bit error ratio (QBER) in the time state is around 0.034%, and the QBER in the phase state is around 28%. The VPG has fulfilled the requirements of system indicator and has been put into use in actual single-mode fiber channel MDIQKD experiments.

Previously reported HPLC-evaporative light scattering detection methods for terpene trilactone determination in Ginkgo biloba leaf extract (EGBL) have complicated sample preparation steps and are time-consuming. Thus, in this work, an HPLC-MS method for the determination of terpene trilactones in EGBL was developed with a novel analytical quality by design approach to provide robust and simple measurements. For this purpose, analytical target profiles and systematic risk analyses were performed to identify potential critical method attributes and critical method parameters. After screening experiments, a Box-Behnken design approach was utilized to investigate the relationships between critical method attributes and critical method parameters. A hypercube design space obtained by a Monte Carlo method was used for choosing the analytical control strategy. Then, verification experiments were performed within the design space, and the models were found to be accurate. After that, the optimized method was verified and successfully used for quality control analysis of EGBL from different manufacturers, and the results were almost the same as those determined by HPLC-evaporative light scattering detection. To our knowledge, this is the first study to establish a robust HPLC-MS method for determination of terpene trilactones in EGBL based on a novel analytical quality by design concept, which can improve the quality control of commercial EGBL.

Introduction Charged aerosol detection (CAD) has the merits of high sensitivity, high universality and response uniformity. The strategy that combines the quantitative analysis of multi-components by single marker (QAMS) with CAD has certain advantages for the quantification of multi-components. However, relevant research was limited. Objectives To comprehensively investigate the crucial factors that affect the performance of the HPLC-CAD-QAMS approach and validate the credibility and feasibility of the method. Methodology Multiple components of Qishen Yiqi dripping pills (QSYQ) were assayed using the high-performance liquid chromatography (HPLC)-CAD-QAMS approach. Some factors that affect the sensitivity and accuracy of the approach were sufficiently studied. After the method verification, principal component analysis (PCA) was applied to evaluate the quality consistency of three types of samples: normal samples, expired samples and negative samples. Results A HPLC-CAD-QAMS method was successfully developed for the multi-component determination of QSYQ. First, chromatographic conditions were optimised by a definitive screening design, and the optimised ranges of operating parameters were obtained with a Monte Carlo simulation method. Next, a new method to select the internal reference standards was successfully introduced based on the heatmap of Pearson correlation coefficients of the response factors. Then, the multi-point method was selected to calculate the relative correction factors, and a robustness test was conducted with Plackett-Burman design. Finally, the PCA was proved to be effective for the quality consistency evaluation of different samples. Conclusion The developed HPLC-CAD-QAMS method can be a reliable and superior means for the multi-component quantitative analysis of QSYQ.

This paper presents a comprehensive analysis on Software Defined Network (SDN) based on these following main aspects: i) an overview of the SDN architecture, ii) the introduction of a practical SDN application, iii) characteristics and drawbacks of SDN, and iv) methods for improving the performance of SDN. By reviewing and researching the rise and development of SDN, it is proposed that SDN solves many issues of traditional distributed networks, including configuration and management difficulties due to network node diversity. However, it still has some limitations, such as decentralize tendency and code opacity caused by competition among vendors. The goal of SDN development is to put SDN in the details of real issues, to improve it from different aspects, and thus make it as a better network.

Although some investigations have been performed to determine the effects of transfusion load and suction pressure on renal function during intraoperative salvage autotransfusion, the precise threshold is still undetermined. A total of 625 patients undergoing surgery with the Continuous AutoTransfusion System (CATSplus) were enrolled and divided into groups according to the utilized suction pressure and transfusion volume. Plasma free hemoglobin (FHB) and creatinine clearance (CCr) were assayed to indicate the renal function. Both 0.03 MPa suction (≥4-unit load) and >5 units transfusion changed the levels of FHB and CCr significantly when measured 24 h post-operation compared to pre-operation. Under 0.02 MPa suction (≥4-unit load), the alteration of FHB and CCr returned to normal after 24 h. Under 3 units transfusion, the levels of FHB and CCr at 6 and 12 h post-operation changed significantly compared to pre-operation (P

By combining a hard template with a dynamic negative template, orderly aligned micrometer-length manganese nanotubes (Mn-NTs) decorated with nanopores on their walls as the secondary structure are successfully grown by electrodeposition in aqueous solution. These nanopores were characterized and analyzed statistically. It is found that these nanopores evolve along the growth direction of the Mn-NTs and their morphology is well controlled by the deposition potential. In addition, the morphology evolution of the nanopores exhibits distinguished size distribution compared with that found in conventional nanoporous foam grown solely by the dynamic template approach, which is attributed to the nanoconfinement of the hard template.

Compared with discrete variable quantum key distribution, the Continuous Variable Quantum Key Distribution (CVQKD) system has the advantages of simple equipment, low technical difficulty, and high channel capacity, in addition to unconditional security and detectability for wiretapping. In this paper, the laser light source control system realizes the control and adjustment functions of the photon quantum state, which was encoded with information. In order to generate the synchronous optical pulse signals, the Field Programmable Gate Array (FPGA), multi-channel Digital to Analog Converter (DAC), and micro power Analog to Digital Converter (ADC) were used to control the synchronous optical laser. The control of multiple amplitude modulators and phase modulators is achieved based on the FPGA and high-speed DAC. At present, the electronics performance test of the laser light source control system has been completed, and the results show that the requirements of the CVQKD system index are met.

Objectives The present study investigated the feasibility of preparing high-purity shikimic acid (SA) from the chromatography wash effluent of Ginkgo biloba leaf extract by macroporous resin. Methods First, static/dynamic adsorption and desorption were conducted to screen out the optimal resin. Second, the key parameters of the chromatographic process were optimised with face-centred central composite design (CCD). Third, wash effluent indices were measured, different batches of wash effluent were used to prepare SA under the optimised parameters, and the effect of varying feed solution compositions on final products was investigated. Key findings It was found that the final purity and recovery rate of SA prepared with ADS-21 resin were not lower than 70 and 60%, respectively, when the purity of SA in the wash effluent was higher than 21.4%. The quality of the final product can be predicted based on the properties of wash effluent. Conclusions The proposed method could not only provide a simple, green and promising approach for the large-scale purification of SA from wash effluent but also be used to develop process intermediate quality standards for other natural products.

A chemical-crosslinked, biocompatible and injectable hydrogel was formed by Fenton reaction initiated polymerization. The gelation time of N-(2-hydroxyethyl)acrylamide and PEG-diacrylate, which are two representative monomers, was shown to be tunable from instant to 15 min at an H2O2 concentration below several mmol L−1 in neutral medium. The strength of the hydrogel could be regulated by the concentration of the monomer and the Fenton's reagent. The hydrogels prepared by H2O2/Fe2+ initiation showed low cytotoxicity. The bone marrow mesenchymal stem cells and L929 cells encapsulated in the gels exhibited high viability even after 7 days of co-culture. Both the L929 cells encapsulated in situ into the hydrogels and those co-cultured with the hydrogel showed negligible cell death and apoptosis. It is anticipated that the familiar Fenton reaction may act as a new initiator system to fabricate biocompatible injectable hydrogels.

Blind lifts on congested offshore platform (OP) environments are inherently dangerous because of the substantial presence of spatial conflicts in the crane workspace and the operator’s limited visi...

BACKGROUND AND PURPOSE In-hospital complications after stroke represent barriers to optimal recovery and are even potentially life-threatening. Anemia is common in stroke patients and is related to poor outcome after stroke. Less is known, however, of the association of anemia with complications. We aimed to investigate the impact of anemia on a series of in-hospital complications after ischemic stroke. METHODS Consecutive patients with ischemic stroke within 7 days were included. Anemia on admission and its severity were defined according to World Health Organization criteria. Eight pre-specified complications, such as pneumonia, gastrointestinal bleeding (GIB) and hemorrhagic transformation, were recorded during hospitalization. RESULTS A total of 2647 patients were included. Anemia was present in 648 patients (24.5%), and 883 patients (33.4%) experienced at least one complication. Patients with anemia were more likely to experience one or more complications, pneumonia, GIB and thromboembolism (all P

With increasing trends in globalization and international trade, the demand for transportation of goods by sea has been growing at an unprecedented rate. This has motivated the industries to build more vessels of greater size and better efficiency, which will enable the shipping industry to provide transport services at lower cost. Notwithstanding the importance of shipping market study in investment decision making, there are relatively few empirical studies modeling the dynamics between shipping demand and fleet supply by considering the incremental trend in vessel size. This chapter examines the nature of the shipping market and then provides a simultaneous model of ship orders, earnings and capacity decisions, and tests it using data. The primary findings point to the impact of vessel size on new investment and fleet development; and order book volume is a significant factor for capacity development which could lead to overcapacity in the market if not well organized.

One of the major challenges in the synthesis of ferromagnetically filled carbon nanotubes is the achievement of high coercivities. Up to now the highest coercivity has been shown to be 2200 Oe at 2 K ranging down to 500 Oe at temperatures of 300 K. Here we show that the anomalously large coercivity of 3440 Oe is observed in comparable samples. By comparing our result to those reported in previous studies no correlation is found between coercivity and the shape anisotropy or the crystal-diameter. Instead we suggest that the main parameter which controls the coercivity of these structures is the interplay of the grain size and shape anisotropy. We attribute the anomalous coercivity to the grain size being below the calculated single magnetic domain limit.

We report calculations of the crystal structures and lattice dynamics of the tetragonal and orthorhombic phases of the molecular crystal hydrogen cyanide, HCN, using density functional theory methods. By treating negative pressure as a proxy for raising temperature we show that the ferroelastic phase transition involves softening of a transverse acoustic mode, and confirm that the phase transition is discontinuous. Analysis of the complete phonon spectrum shows that the acoustic modes are responsible both for the very large thermal expansion seen in HCN and also for the thermodynamic driving force for the phase transition.