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The effects of inoculating plant growth promoting rhizobacteria (PGPR) and soil water deficits on crop growth and physiology remain largely unknown. Here, the responses of leaf gas exchange, growth, and water use efficiency (WUE) of tomato plants to Bacillus pumilus (B.p.) inoculation under four irrigation strategies (I1-I4) were investigated in a greenhouse. Results showed that soil water deficits, especially at I4 (20%, v/v), significantly decreased leaf stomatal conductance (gs), transpiration rate (Tr), and photosynthetic rate (An), and the decrease of gs and Tr were more pronounced than An. Reduced irrigation regimes significantly lowered dry matter and plant water use both in the non-B.p. control and the B.p. plants, while reduced irrigation significantly increased plant WUE, and B.p. inoculation had little effect on this parameter. Synergistic effects of PGPR and deficit irrigation on leaf gas exchange, leaf abscisic acid content, and stomatal density were found in this study, and specifically, B.p. treated plants at I4 possessed the highest WUE at stomatal and leaf scales, suggesting that B.p. inoculation could optimize water use and partly alleviate the negative effects of soil water deficit. These findings provide useful information for effective irrigation management and the application of PGPR in agriculture in the future.

To the best of our knowledge, the spectroscopic and highly efficient tunable multi-wavelength laser properties of Er3+,Yb3+,Pr3+ triple-doped BaLaGa3O7 crystals are demonstrated for the first time in this study. The maximum output power of 0.81 W at ∼2.7 μm was obtained under the absorbed pump power of 3.53 W with an optical-to-optical conversion efficiency of 22.9%. The slope efficiency is 27.0%. The results demonstrate that the triple-doped crystals with the sensitizer Yb3+ and deactivator Pr3+ can not only enhance the pump efficiency effectively but also suppress the self-terminating "bottleneck" effect of Er3+ so that the laser threshold is reduced and the laser efficiency is improved. The Er3+,Yb3+,Pr3+ triple-doped BaLaGa3O7 crystal is a promising candidate for high-efficiency mid-infrared laser devices. [ABSTRACT FROM AUTHOR]

Amorphous aerogels with the microscopic nanoscale three-dimensional meshes provide superb platforms for investigating unique physicochemical properties. In order to enhance the physical, thermal and mechanical performances, one efficient and common approach is integrating diverse functional materials. Herein, we report a simple strategy to fabricate the amorphous silicon doped Y2O3 aerogels with the post-gelation method under the N2/EtOH supercritical atmosphere. The impact of Si concentration on the nonlinear optical properties is investigated for the first time. The maximum modulation depth is 1.65 % with a saturation intensity of 0.78 MW cm−2 with the 1-ps laser excitation at 1590 nm. Finally, we incorporated the silicon-doped Y2O3 aerogel based saturable absorber (SA) into an erbium-doped fiber laser (EDFL) and achieved various mode-locking operations at different wavelengths in the super C band, in terms of the conventional soliton, harmonic soliton molecules pulses, and dual-wavelength soliton mode-locking. Overall, this work confirms that amorphous silicon-doped Y2O3 aerogels are good nonlinear optical materials and pave a way for the ultrafast photonic and nonlinear optical applications with amorphous materials in near future. [ABSTRACT FROM AUTHOR]

Arterial stiffness has been proved to be an important parameter in the evaluation of cardiovascular diseases, and Pulse Wave Velocity (PWV) is a strong indicator of arterial stiffness. Compared to regional PWV (PWV among different arteries), local PWV (PWV within a single artery) outstands in providing higher precision in indicating arterial properties, as regional PWVs are highly affected by multiple parameters, e.g., variations in blood vessel lengths due to individual differences, and multiple reflection effects on the pulse waveform. However, local PWV is less-developed due to its high dependency on the temporal resolution in synchronized signals with usually low signal-to-noise ratios. This paper presents a method for the noninvasive simultaneous measurement of two local PWVs in both left and right radial arteries based on the Fiber Bragg Grating (FBG) technique via correlation analysis of the pulse pairs at the fossa cubitalis and at the wrist. Based on the measurements of five male volunteers at the ages of 19 to 21 years old, the average left radial PWV ranged from 9.44 m/s to 12.35 m/s and the average right radial PWV ranged from 11.50 m/s to 14.83 m/s. What is worth mentioning is that a stable difference between the left and right radial PWVs was observed for each volunteer, ranging from 2.27 m/s to 3.04 m/s. This method enables the dynamic analysis of local PWVs and analysis of their features among different arteries, which will benefit the diagnosis of early-stage arterial stiffening and may bring more insights into the diagnosis of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

BACKGROUND With the increased attention paid for the construction of ecological civilization, a comprehensive survey of natural resources is imperative, and new requirements for biological reference materials have also been put forward. At present, relevant research work has been widely carried out. The comprehensive investigation of natural resources, agricultural products and food safety evaluation all need to accurately test the element composition of biological samples, and biological reference materials are needed as the basis for the comparison and traceability of biological components. The demand for biological matrix reference materials has increased significantly. As one of the main foods, the food safety of rice has been paid more and more attention. It is of great practical significance to carry out accurate analysis of the chemical components in rice. Therefore, the demand for rice is particularly prominent, but the rice reference materials for composition analysis are still lacking. OBJECTIVES To develop rice certified reference material (GBW10010a) and compare it with the data characteristics of GBW10010. METHODS The rice certified reference material (GBW10010a) was prepared in strict accordance with relevant specifications. The collected candidates were prepared through coarse crushing, drying, fine crushing, sieving, blending and other steps. The particle size distribution was detected by BT-9000ST laser particle size analyzer. 15 bottle samples were randomly selected and homogeneity testing was carried out by ICP-MS and ICP-OES, etc. The data were statistically calculated by one-way ANOVA, indicating good homogeneity of the samples. The long-term stability of the standard material under the specified storage conditions was investigated. The linear model was used to evaluate the stability of the sample. The determination of 60 components was carried out by means of ICP-MS, ICP-OES, AFS, COL, VOL, XRF, IC and other Analytical test methods. RESULTS The rice reference material prepared in this research has diverse fixed value components, accurate and reliable measurement values, and meet the requirements of national first-level reference material. GBW10010a has a total of 54 main trace elements. 39 elements have certified values and uncertainties and 15 elements only have reference values. The content of heavy metal elements such as As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Zn in GBW10010a decreased significantly, among which Cd, Cu, and Zn decreased by about 39%, 43% and 38.7%, respectively. CONCLUSIONS To a certain extent, the values reflects the improvement of farmland ecological environment. Compared with the original GBW10010, the total number of certified value elements has increased by 6 items, including Ag and Nb (Nb gives reference values). Moreover, the uncertainty of each element is reduced, including biological-related elements Al, Cd, Cu, Fe, K, Mg, Mo, Na, P, Pb, Se, and Zn. The reduction indicates the technological advancement of the geological analysis and the improvement of the certified value level. In addition, the content of heavy metal elements in GBW10010a decreased significantly, reflecting the improvement of farmland ecological environment. The designated elements of the reference materials cover most of the main and trace elements with biological effects, and are suitable for the calibration of analytical instruments, evaluation of analytical methods, and monitoring analytical quality during agricultural ecological environment geochemical surveys and evaluation, biological sample analysis, agricultural product quality and food safety evaluation.

Mid-infrared (MIR) photonics has attracted tremendous interest because of its broad applications at atmospheric windows. In this work, we report high-performance MIR photonics based on large-scale and good-quality monolayer molybdenum disulfide (MoS2). The open-aperture Z-scan measurement on the nonlinear saturable absorption features shows that the as-grown monolayer MoS2 possesses a modulation depth of 26% and a low saturable intensity of 271 kW/cm2, enabling its application as an excellent saturable absorber for the MIR pulse generation. This is further evident by the measured high effective nonlinear absorption coefficient βeff (−16 cm/MW). In addition, the two-photon absorption coefficient and the nonlinear refractive index of monolayer MoS2 are also determined by the closed-aperture Z-scan technology. As an application, we demonstrate a passively Q-switched Tm,Ho:CaLu0.1Gd0.9AlO4 (Tm,Ho:CLGA) disordered crystal laser at 2.1 μm by using the monolayer MoS2 as the saturable absorber for the first time, producing a minimum pulse width of 765 ns and a pulse repetition rate of 36 kHz. Our results demonstrate that large-scale monolayer MoS2 is a promising candidate for the MIR photonic applications.

When solving traveling salesman problem (TSP), the ant colony algorithm is easy to fall into local optimum and convergence speed is slow, a double-type ant colony algorithm considering dynamic guidance and neighborhood interaction is proposed. Firstly, the algorithm combines the dynamic guidance strategy to increase the dynamic pheromone belonging to the path of the largest spanning tree in the early iteration, thereby effectively increasing the diversity of the population; adding the dynamic pheromone belonging to the path of the minimum spanning tree in the late iteration to accelerate the convergence speed. Furthermore, the ants are divided into two categories, which are integrated into the neighborhood interaction strategy, and the second type of ants improve the state transition and the local pheromone update formula through the attraction factors, and use the MMAS (max-min ant system) pheromone restriction strategy, which not only improves the convergence, but also prevents the algorithm from early stagnation. The experimental results of solving the TSP test set and compared with other improved ant colony algorithms show that the improved algorithm can effectively accelerate the convergence speed and avoid falling into local optimum, thus obtaining a more accurate solution, especially in the case of large-scale TSP problems, the effect is more significant.

Curcin and Curcin C, both of the ribosome-inactivating proteins of Jatropha curcas, have apparent inhibitory effects on the proliferation of osteosarcoma cell line U20S. However, the inhibitory effect of the latter is 13-fold higher than that of Curcin. The mechanism responsible for the difference has not been studied. This work aimed to understand and verify whether there are differences in entry efficiency and pathway between them using specific endocytosis inhibitors, gene silencing, and labeling techniques such as fluorescein isothiocyanate (FITC) labeling. The study found that the internalization efficiency of Curcin C was twice that of Curcin for U2OS cells. More than one entering pathway was adopted by both of them. Curcin C can enter U2OS cells through clathrin-dependent endocytosis and macropinocytosis, but clathrin-dependent endocytosis was not an option for Curcin. The low-density lipoprotein receptor-related protein 1 (LRP1) was found to mediate clathrin-dependent endocytosis of Curcin C. After LRP1 silencing, there was no significant difference in the 50% inhibitory concentration (IC50) and endocytosis efficiency between Curcin and Curcin C on U2OS cells. These results indicate that LRP1-mediated endocytosis is specific to Curcin C, thus leading to higher U2OS endocytosis efficiency and cytotoxicity than Curcin.

Background: Total percutaneous closure for the site of femoral arterial puncture using Perclose ProGlide (PP) has become prevalent post-percutaneous endovascular aortic repair (EVAR) and veno-arterial extracorporeal membrane oxygenation (VA-ECMO).Objective: To evaluate the safety and efficacy of total percutaneous closure of the femoral artery access site post-EVAR compared with VA-ECMO.Methods: This was a retrospective observational study conducted over 4 years, including 88 patients who underwent EVAR (64 patients) and VA-ECMO (24 patients). Perclose ProGlide devices were used in the femoral artery puncture sites closed percutaneously. In this study, technical success was defined as successful arterial closure of the common femoral artery (CFA) without additional surgical or endovascular procedures to prevent vessel leaking. Access site complications, including overt bleeding requiring transfusion or surgical intervention, minor bleeding, tinea cruris, pseudoaneurysm, and lymphocele, were recorded 24 h and 30 days after arterial closure.Results: Each group's technical success rates were 95.8% (VA-ECMO) and 92.2% EVAR, respectively. There were no differences in the periprocedural complications of major bleeding, pseudoaneurysm, minor bleeding, acute limb ischemia, and groin infection. Furthermore, we did not observe any complications such as arterial thrombosis, dissection, stenosis, arteriovenous fistula, hematoma, groin infection, or lymphocele at the access site by following-up an ultrasound examination. There was no significant difference in the technical success rate of percutaneous closure by the PP device in the EVAR and VA-ECMO oxygenation groups. Also, no periprocedural or 30-day complications were observed at the access site of the EVAR and VA-ECMO patients.

High‐entropy alloys (HEAs) possess superior mechanical, thermal, and electronic properties, which attract great interest in the fields of photothermal, electrocatalysis, and magnetic applications. Herein, the nonlinear optical properties of FeCoNiAlTi HEA with a large specific surface area for the first time is investigated. Owing to the strong d–d interaction, the interband transition near the Fermi level could be enhanced in HEAs, leading to broadband optical absorption. Excitation with the picosecond laser source, the FeCoNiAlTi HEA possesses saturable absorption with a large modulation depth of 7.61% and 30.47% at 1 and 1.5 µm, respectively. Furthermore, at the higher excitation level at 1.5 µm, the saturable absorber exhibits a typical reverse saturable absorption property. Subsequently, the FeCoNiAlTi HEA on the tapered fiber first serves as the saturable absorber in the Yb‐doped fiber laser and the Er‐doped fiber laser, leading to the noise‐like pulses at 1 µm, and the stable Q‐switching, conventional soliton, and dissipative soliton resonance mode‐locking operations at 1.5 µm. This work confirms that the enhanced saturable absorption in HEAs can endow the high‐performance ultrashort pulse generation. [ABSTRACT FROM AUTHOR]

Herein, we describe a copper‐catalyzed sequential C(sp2)−H/C(sp3)−H annulation of indoles with propargylic alcohols for the synthesis of diversely functionalized hydrobenzo[b]carbazole scaffolds. The reaction involves a Friedel‐Crafts addition, 1,5‐H shift, 6π electrocyclization, and dearomatization‐aromatization cascade. Importantly, this is a report of the use of 2‐(diarylmethyl)indoles as three‐carbon synthons in a (3+3) annulation reaction involving C(sp3)−H indole functionalization under oxidant‐free conditions. [ABSTRACT FROM AUTHOR]

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The role of d subunit-containing GABA[subscript A] receptor (GABA[subscript A](d)R) in fear generalization is uncertain. Here, by using mice with or without genetic deletion of GABA[subscript A](d)R and using protocols in which the conditioned tone stimuli were cross presented with different nonconditioned stimuli, we observed that when the two tone stimuli were largely similar, both genotypes froze similarly to either of them. However, when they differed markedly, the knockout mice froze much more than their wild-type littermates to the nonconditioned but not conditioned stimuli. Thus, GABA[subscript A](d)R may prevent inappropriate fear generalization when the incoming stimuli differ clearly from the learned threat.

BACKGROUND Floodplain sediment, which is an important sampling media for geochemical mapping, can represent the average distribution of elements in the basins and has universal applicability. At present, there is no floodplain sediment reference material in the world. The development of similar standards in foreign countries focuses on the environment, and there are fewer fixed components. The same standards for soil and river sediments in China are limited by different work needs, and the development aims are different. Most of the standard substances are insufficient. To develop 7 national first-level reference materials for floodplain sediments in the Yangtze River, Gan River, Han River, Huaihe River, Yellow River, Haihe River and Heilongjiang River (GBW07385-GBW07391). CANDIDATES CHARACTERISTICS:Sample GSS-29 is the floodplain sediment of the Yangtze River. It is grayish yellow and contains high contents of silty. GSS-30 is the floodplain sediment of the Gan River, which is sub clay with relatively fine particle size. GSS-31 is the floodplain sediment of the Han River, which is gray-black, fine-grained and contains relatively high contents of organic matter. GSS-32 is the floodplain sediment of the Huaihe River, which is grey-black, fine-grained and clay-like. GSS-33 is the floodplain sediment of the Yellow River, which is black clay with relatively fine grain size and relatively high contents of organic matter. GSS-34 is the floodplain sediment of the Haihe River, which is sub clay with a relatively fine grain size and high content of clay formed in block. GSS-35 is the floodplain sediment of the Heilongjiang River, which is black and loose, with a relatively fine grain size and high content of clay where some are formed in block. METHODS A series of reference materials was tested using X-ray Fluorescence Spectrometry to measure 26 components. The RSD of the main components was less than 1%, the RSD of minor elements was 2% and the RSD of trace components was less than 7%. The F value of the variance test was less than the list threshold F0.05(24,25)=1.96, indicating that all seven materials were homogeneous. No significant statistical changes were found in the 24 elements and compounds tested within 23 months, indicating that the stability of these materials were stable. Thirteen laboratories have participated in this inter-laboratory program, and have adopted various reliable analytical methods based on different principles to set the values. RESULTS A total of 511 characteristic components, including 73 elements and compounds, have been tested. In addition to the CO2 values of GBW07386 and GBW07388 that cannot be assigned, the remaining 494 characteristic components are given the certified value and uncertainty, and 15 characteristic components are given information value. The trace elements in GSS-29 have the mostly high background contents. The trace elements in GSS-30 have medium background values, and the contents of W, Sn and Mo are relatively high. The contents of Cd and Mo in GSS-31 are relatively high. The trace elements in GSS-32 have low background contents, and the contents of Cd, Hg, Mo, N, S and P are lower than the background level. The content of Hg in GSS-33 is very low. The trace elements in GSS-34 have the mostly medium and high background levels, and the contents of F, Cl and Br are relatively high. The organic matter content of GSS-35 is relatively high. CONCLUSIONS The seven reference materials for floodplain sediments have been certified by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China (AQSIQ) in 2017. This series of floodplain sediment certified reference materials (GBW07385-GBW07391) represents the background values of the elements of each corresponding drainage area. It can be used for monitoring the quality of geochemical sample analysis or the quality of sample analysis in other fields, such as environment and agriculture.