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Six instructional methods used by teachers to introduce new topics in mathematics and their effect in student's understanding and performance are evaluated by focusing on Third International Mathematics and Science study data.

Bacillus thuringiensis(Bt) transgenic cotton (Gossypium hirsutumL.) has been widely planted in Asia. However, efficacy of the Bt protein to kill pests has been inconsistent. Effects of gibberellic acid (GA3) and dimethylpiperidinium chloride (DPC) on boll Bt protein content were investigated on ‘Sikang1’ and ‘Siza3.’ Treatment of DPC increased the Bt protein contents in carpel wall and cotton seed at 10 d after flowering (DAF) and 30 DAF in 2014 and 2015. However, Bt protein contents of the GA3treatment only at 30 DAF were higher for both cultivars in comparison to the control. To further investigate the mechanism, we found the ability of protein synthesis (indicated by enzyme activities of nitrate reductase [NR], glutamic‐pyruvic transaminase [GPT], and glutamic oxaloacetate transaminase [GOT], as well as contents of total nitrogen, free amino acid, and soluble protein) in bolls increased markedly with the application of DPC for both cultivars. Further analysis showed that there were positive linear correlations between Bt protein content and NR, GPT, and GOT activities and total nitrogen and soluble protein contents (r= 0.925∗∗, r= 0.691∗∗, r= 0.703∗∗, r= 0.682∗, r= 0.693∗∗, respectively) in carpel wall of bolls. Thus, DPC is potentially an effective chemical application to increase boll Bt protein content. Core IdeasDimethylpiperidinium chloride (DPC) application can bolster boll insect resistance.Significant linear positive correlation between Bt protein content and ability of synthesis the protein was found in boll shell.DPC increases Bt protein content through increasing ability of synthesis the protein. Dimethylpiperidinium chloride (DPC) application can bolster boll insect resistance. Significant linear positive correlation between Bt protein content and ability of synthesis the protein was found in boll shell. DPC increases Bt protein content through increasing ability of synthesis the protein.

Hierarchical Linear Models (HLMs), using the data from the Longitudinal Study of American Youth (LSAY) to model the growth of student science achievement in three areas of biology, physical science, and environmental science, during the middle and high school is discussed.

The SIGIR'20 Women in IR event, co-organized by SIGIR WIR co-chairs, Nazli Goharian and Suzan Verberne, and local co-chair of SIGIR'20 WIR, Xin Ma, took place on July 27-29 and was attended by ~150 participants from different parts of the earth. Due to Covid-19, SIGIR'20 was held online. To accommodate all the time zones, we organized two sessions (A and B) on the same topics of discussion with two disjoint sets of panelists1, each group covering one of two sessions, totaling 19 panelists (17 female and 2 male) from academia and industry. This year we raised two questions for our panellists to discuss, followed by Q&A by the audience. First we discussed the women's status as to holding key leadership roles both in the academia and industry. The second topic was gender inequity in pay, which we had already raised for the first time in our community in SIGIR'19 and was summarized in the WIR at SIGIR'19 Forum2. [ABSTRACT FROM AUTHOR]

Gabor features have been shown to be effective for palm vein recognition. This paper presents a novel feature representation method, implementing the fusion of local Gabor histograms (FLGH), in order to improve the accuracy of palm vein recognition systems. A new local descriptor called local Gabor principal differences patterns (LGPDP) encodes the Gabor magnitude using the local maximum difference (LMD) operator. The corresponding Gabor phase patterns are encoded by local Gabor exclusive OR (XOR) patterns (LGXP). Fisher's linear discriminant (FLD) method is then implemented to reduce the dimensionality of the feature representation. Low-dimensional Gabor magnitude and phase feature vectors are finally fused to enhance accuracy. Experimental results from Institute of Automation, Chinese Academy of sciences (CASIA) database show that the proposed FLGH method achieves better performance by utilizing score-level fusion. The equal error rate (EER) is 0.08%, which outperforms other conventional palm vein recognition methods (EER range from 2.87% to 0.16%), e.g., the Laplacian palm, minutiae feature, Hessian phase, Eigenvein, local invariant features, mutual foreground local binary patterns (LBP), and multi-sampling feature fusion methods.

The echo width is one of the most essential parameters of waveforms, which can be used to evaluate the ranging performance of a laser altimeter or retrieve wind speeds when laser pulses illuminate on the sea surface. The classical expression of waveform widths is not suitable for a current satellite laser altimeter because only the waves on the sea with smaller wavelengths can be covered by a satellite laser altimeter due to its small footprint. A new expression is derived by dividing the broadening effect of echo widths into the wind wave with small wavelengths and the swell cause with large wavelengths. The Geoscience Laser Altimeter System (GLAS) and National Centers for Environmental Prediction (NCEP) data are used to verify the new expression. Based on the new echo width expression, the ranging performance is evaluated when a laser is illuminating on the ocean surface. It indicates that a laser altimeter performs a better ranging accuracy (better than 5 cm) than when it is evaluated using the classical expression (worse than 6 cm) at moderate and strong winds.

In this paper, we propose a security-oriented transmission scheme with the help of multiple relays in Cognitive Radio (CR). To maximise the Secrecy Capacity (SC) of the source-destination link in CR, both beamforming and cooperative jamming technologies are used to improve the performance of the Secondary User (SU) and protect the Primary User (PU). The effectiveness of the proposed scheme is demonstrated using extensive simulation. Both theoretical analyses and simulation results reveal that the proposed scheme contributes to the secure transmission of the SU with acceptable attenuation of the Signal-to-Noise Ratio (SNR) at the PU receiver, and the upper bound of the SC at the SU receiver is able to exploit the power allocation strategy.

AbstractBased on the analysis of hanging rivers’ actuality in the lower Yellow River and researches related to the evaluation of dike breach risks, it is put forward that the influencing factors of dike beach risks in the lower Yellow River should involve four aspects, the flow and sediment movement, the regional crustal stability, the variation of river regime and the stability of river dikes. With this, the evaluation indexes system of dike breach risks is established, and with the support of geographic information systems technology, the model of multi-hierarchical fuzzy comprehensive judgment is applied to estimate the dike beach risks of the hanging rivers in the lower Yellow River under different flood conditions. The evaluation results of dike breach risks show the following distributing regularities of dike breach risks in the lower Yellow River: (1) Dike breach risks increase with the increase of the flood. (2) Dike breach risks decrease with the changes of river patterns along the channel. (3) There are great risks of dike breach in the wandering reaches, and it is relatively higher in the south bank than in the north in wandering reaches. (4) There is a higher dike breach risk in the north bank than in the south in winding reaches. Simultaneously, the evaluation results manifest that the evaluation indexes system established from the flow and sediment movement, the regional crustal stability, the variation of river regime and the stability of river dikes can represent the actual situation of the lower Yellow River more comprehensively. The application of multihierarchical fuzzy comprehensive judgment can preferably resolve the problem of hanging river dike breach, which has numerous influencing factors and complicated functionary mechanisms. The applications of geographic information systems technology with powerful spatial analysis functions make dike beach risks quantificationally displayed in different spatial positions, and reflect the differences of dike beach risks in different spatial positions of the channel in the lower Yellow River.

The article discusses the adulteration challenges faced by the dietary supplement industry. It discusses the adulteration due to increasing popularity of natural sourced ingredients, Huperzine A, a plant-based nutraceutical that vulnerable to adulteration through the fraudulent use of petrochemical-derived synthetics.

This paper presents the use of a high performance dual-plane electrical resistance tomography (ERT) system and a local dual-sensor conductance probe to measure the vertical upward oil-in-water pipe flows in which the mean oil volume fraction is up to 23.1%. A sensitivity coefficient back-projection (SBP) algorithm was adopted to reconstruct the flow distributions and a cross correlation method was applied to obtain the oil velocity distributions. The oil volume fraction and velocity distributions obtained from both measurement techniques were compared and good agreement was found, which indicates that the ERT technique can be used to measure the low fraction oil-water flows. Finally, the factors affecting measurement precision were discussed.

AbstractA new species of Culicoides, C. tahemanensissp. nov. is described from Xingjiang Uygur Aut. Reg. in China. The new species is closely allied to Culicoides grisescensEdwards, but both of them are distinctly different in pale spots of cell R5and cell A of wing of female, and shape of distal portion of aedeagus of male. The ninth tergum of new species is somewhat allied to C. nipponensisTokunaga, but distinctly different in pale spots of cell R5, cell M2and cell A of wing, and shape of aedeagus of male. The type speciemens are deposited in the Institute of Military Medical Sciences, Shenyang Military District, Shengyang 110034, China.

AbstractA new pendant-arms macrocyclic ligand 3,4:9,10:17,18:23,24-tetrabenzo-5,8,19,22-tetraoxa-1,12,15,26-tetraazacyclooctacosane N.N′,N″,N′″-tetraacetic acid (H4L) was synthesized by alkylating 3,4:9,10:17,18:23,24-tetrabenzo-5,8,19,22-tetraoxa-1,12,-15,26-tetraazacyclooctacosane with BrCH2COOK in absolute methanol solution. H4L contains a coordinated potassium ion. Its transition metal complexes were also prepared in high yields. All compounds were characterized by IR, NMR, elemental analyses, UV-VIS and TG-DTA. The complexes have the formula [M2KL]Cl·nH2O (M = Co(II). Zn(II), Cd(II), Hg(II): n = 2∼2.5) except Ni2L·5H2O and [CuKH2L](ClO4) · 3H2O.Referee I: S. BottReferee II: K. Moedritzer

Summary: In a perfused isovolumetrically contracting rat heart model, the effects of isoprenaline (IPN) and phenylephrine (PE) on myocardial contraction and relaxation were investigated, and the influence of nifedipine on these effects was studied. Both IPN and PE increased the myocardial contraction and improved its relaxation, but some differences existed. Nifedipine (10 nmol/L) substantially inhibited the PE-mediated inotropic effect, but in case of IPN-niediated inotropic ones, it did not. It was assumed that there may be various types of slow channels, one was activated by IPN, and the other, by PE.

Summary: The effects of amrinone on cardiac contraction and relaxation were assessed in isolated, perfused rat hearts. It was found that the left ventricular developed pressure (LVDP). dp/dtmax and -da/dtmax did not significaptly increase, and the time constant (τ) did not markedly shorten with perfusion of low concentration (1 nmol/L. 100 nmol/L) of amrinone. The perfusion with higher concentration (1000 nmol/L) of amrinone. reduced LVDP (P<0.01), dp/dtmax (P<0.01), -dp/dtmax, (P<0.01), and prolonged τ (P< 0. 05) significantly. It was assumed that amrinone has no direct positive inotropic effect, and can not improve cardiac relaxation. On the contrary, the cardiac contraction and relaxation will be inhibited at higher concentration of amrinone.

Due to the characteristics of high temperature oxidation resistance and high reliability, all oxide composites are ideal materials for components in hot end of aeronautics and astronautics. In this paper, all oxide ceramic matrix composite(CMC) was prepared by a novel method which combined warm pressing of prepreg with PIP using polysilialumoxane as the precursor of mullite. The morphology, structure and mechanical properties of the all oxide CMC were characterized. The results show that polysilialumoxane with a ceramic yield of 53wt%can be completely changed to ceramic at 1200degC and form mullite crystals. The composite with alumina and mullite matrix derived from alumina powder slurry indicated the best mechanical properties, the flexural strength and fracture toughness of the composite reach 208.3Mpa and 128.6Mpa respectively, and the pull-out effect of the fibers is obvious in the process of tensile fracture, and the composites show ductile fracture. whereas the mechanical property decreases significantly after heating at 1200degC for100 hours due to the densification of matrix and abnormal growth of alumina grains in fibers.

We investigate the quantum correlated ΛΛ̄ production in the reaction e+e-→J/ψ→ΛΛ̄. Since the Λ or Λ̄ has a nonzero magnetic moment, its spin will undergo a Larmor precession in the magnetic field of the detector, such as the BESIII experiment. Because of the spin precession, the angular distribution of the Λ and Λ̄ is slightly modified. Therefore, we obtain the corresponding term of the modified angular distribution due to the effect of the Larmor precession. We also estimate its potential effect on the measurements of CP violation, as well as the decay asymmetry parameter and polarization of Λ. The polarization of the Λ or Λ̄ at the production vertex will rotate around the B-field axis, over an angle depending on the flight length, but it still could be measured by fit to the corrected angular distribution. Of important note, we conclude that a nonzero CP asymmetry of order 10-4 will be caused once neglecting spin precession of the Λ and Λ̄ in the e+e-→J/ψ→ΛΛ̄ process. The size of this CP asymmetry is several times that of predicted within Standard Model in the hyperon decay. Although this effect is small, it will play an important role in future high precision experiments, such as the super-tau-charm factory. [ABSTRACT FROM AUTHOR]

Terrain recognition is one of the key problems of mobile robots. It can help the robots understand the surrounding environment. With terrain prediction, the robots could realize autonomous navigation and path planning. This paper focuses on image feature selection for terrain recognition with visions. For terrain recognition tasks, feature is used to represent image information. Traditional visual features can be targeted to express the low-level information like color or texture. The deep feature is extracted by self-learning of neural network, containing richer semantic information than low-level features. There is a complementary relationship between the two. The efficiency and accuracy of terrain recognition is remarkably raised by the fusion of two above features. In the course of algorithm, combination of the off-line training model and on-line recognition model is used to identify the terrain type of the sample, which is to ensure the real-time performance. The corresponding terrain dataset--SDUterrain is established. The algorithm achieves 96% or higher classification accuracy in the experiments based on the SDUterrain Dataset, which is much higher than the single feature classification algorithm.

In order to clarify the seasonal variations of plasma sex steroid hormones and vitellogenin (VTG) concentrations in the wild male Japanese dace, Tribolodon hakonensis, we measured plasma levels of testosterone (T), 11-ketotestosterone (11-KT), estradiol-17 β (E2) and VTG, as well as spermatogenetic stages and gonadosomatic index (GSI). Wild Japanese dace were collected from different sites of the Jinzu River basin (including the Takahara River and the Itachi River). The fish from Toyama Bay were also measured the spermatogenetic stages, GSI and VTG levels. The seasonal variations of the hormone levels were discussed in the relationship with various environmental factors. In landlocked fish of the Takahara River, the plasma concentrations of T and E2 reached the highest levels in May and June. In the fish collected from the Itachi River, plasma concentrations of T, 11-KT and E2 reached the highest levels during breeding season of April and May. Sexual maturation, evaluating from GSI and the spermatogenetic stages, proceeded earlier in the fish population at Toyama Bay, and afterward it was followed in the fish population at the Takahara River, in associated with a rise of environmental water temperature at fish captured sites. In the male dace, low but detectable levels of plasma E2 were measured and there were significantly positive correlations between E2 level and the levels of GSI, VTG or T. These results suggest that E2 might be a necessary sex steroid hormone related to gonad maturation, and that circulating E2 may induce VTG production in the wild male Japanese dace. [ABSTRACT FROM AUTHOR]