Dual quaternion-based inverse kinematics of dexterous finger

The inverse kinematics solution of a dexterous robotic finger has a significant impact on the real-time control of the robotic hand. Therefore a rapid method for solving is needed. The classical homogeneous matrix transformation is the most popular method used in robot kinematics. However, for the multi degree-of-freedom (DOF) robotic finger, the matrix parameters cost much storage and the inverse matrix calculation requires a large amount of computational cost. So it is not conducive to the real-time control of the robotic hand. Therefore, a method based on dual quaternions is presented for analysing the kinematics of a multi-DOF (4-DOF) robotic thumb. Firstly, the kinematics equation is expressed by dual quaternions. Then the multivariate kinematic equations are converted to binary quadratic equations with methods of separating variables and variable substitution, which is relatively easy to obtain the closed-form solution of the inverse kinematics. Finally, it proves that the dual quaternions method has advantages over the homogeneous matrix transformation in storage and computational cost by the specific numbers for the robotic thumb, which is conducive to the real-time control of robotic hand

Systematic study of elliptic flow parameter in the relativistic nuclear collisions at RHIC and LHC energies

We employed the new issue of a parton and hadron cascade model PACIAE 2.1 to systematically investigate the charged particle elliptic flow parameter $v_2$ in the relativistic nuclear collisions at RHIC and LHC energies. With randomly sampling the transverse momentum $x$ and $y$ components of the particles generated in string fragmentation on the circumference of an ellipse instead of circle originally, the calculated charged particle $v_2(\eta)$ and $v_2(p_T)$ fairly reproduce the corresponding experimental data in the Au+Au/Pb+Pb collisions at $\sqrt{s_{NN}}$=0.2/2.76 TeV. In addition, the charged particle $v_2(\eta)$ and $v_2(p_T)$ in the p+p collisions at $\sqrt s$=7 TeV as well as in the p+Au/p+Pb collisions at $\sqrt{s_{NN}}$=0.2/5.02 TeV are predicted.Comment: 7 pages, 5 figure

Bioactivity of Cicuta virosa L. var. latisecta Celak. (Umbelliferae: Cicutal) against Red Imported Fire Ant under Laboratory and Field Conditions

We evaluated the bioactivities of compounds from Cicuta virosa L. var. latisecta Celak. against red imported fire ants (Solenopsis invicta Buren) under field and laboratory conditions. The compounds were as follows: methanol extract; petroleum ether, chloroform, and ethyl acetate fractions from the methanol extract; and the active compound isoimperatorin, which was isolated from the chloroform-fraction. The 7 d LC50 values of the methanol extract, petroleum ether, chloroform, and ethyl acetate fractions and isoimperatorin toward micrergates were 111.20, 214.45, 40.90, 569.67, and 25.73 mg/kg, res­pectively. The corresponding LC50 values toward macrergates were 155.78, 308.38, 75.01, 776.75, and 42.77 mg/kg, res­pectively. Under field conditions, baits containing 0.2% methanol extract, 0.1% chloroform fraction, and 0.05% isoimperatorin efficiently controlled S. invicta, with effectiveness percentages of 95.56%, 97.78%, and 95.56%, respectively on the 30th day after bait application. Such effectiveness percentages were not significantly different from that obtained using the positive control fipronil. The present study showed that C. virosa L. var. latisecta has potential as a natural control agent for the red imported fire ants

Effects of hematoporphyrin monomethyl ether (HMME) on Worker Behavior of red imported fire ant, Solenopsis invcita

The effect of hematoporphyrin monomethyl ether (HMME) activated under visible light on worker behavior of Solenopsis invcita was studied with the potter spray tower method. The results showed that greater than 10 mg/L HMME activated under visible light could reduce the walking, grasping, aggregation, and water and food recognition abilities of red imported fire worker ant significantly, but 100 mg/L HMME in darkness could not affect their abilities or behaviors significantly. Therefore, HMME may be a potential novel insecticide that can be used as a substitute for toxic insecticides for controlling red imported fire ants

Equol induces apoptosis in chemoresistant ovarian cancer cells via external pathway

Polyphenolic compounds present in fruits, vegetables and grains are bioactive molecules which elicit a wide range of responses both in vivo and in vitro. The aim of this study was to investigate whether the soybean isoflavone equol could induce apoptosis in ovarian cancer cells. In this study, we evaluated molecular events associated with apoptosis induced by equol and paclitaxel (PTX) in an ovarian cancer cell line SKOV-3. To assess whether growth inhibition was due to apoptosis, flow cytometry, colorimetry experiments, immunoblot analyses through measuring DNA fragmentation, the level of TRAIL,the cleavage of poly(ADP-ribose) polymerase (PARP) and the activation of caspase-3, -8 and -9 were also performed. Additional markers of apoptosis were also measured like phosphatidylserine externalization and morphological changes. In addition, glycoprotein P (P-gp) activity in SKOV-3 ovarian cancer cell line was also estimated. The experimental results showed that apoptosis was induced by extrinsic pathway triggered by certain TNF family members. Overall results suggested that equol induces apoptosis in SKOV-3 cells via a TRAIL and caspase 8-dependent pathway whereas paclitaxel leads to smaller apoptotic events when compared to that of equol

Insecticidal effect of volatile compounds from fresh plant materials of Tephrosia vogelii against Solenopsis invicta workers

The effect of volatile compounds from the mashed fresh bean pods (B) as well as the branches and leaves (L) of Tephrosia vogelii on the behavior of Solenopsis invicta workers was investigated by fumigation toxicity bioassay. Gas chromatography–mass spectrometry analysis was used to identify and quantify the volatile compounds. α-pinene, thujene, caryophyllene, and d-limonene were identified as major components of the volatile compounds, which were found toxic to workers when applied by fumigation. Responses varied according to worker size, exposure time, and plant material. An increase in exposure time from 1h to 12h led to increases in mortality from 18.33% to 100.00% (B) and 13.33% to 100.00% (L) in minor workers as well as increases from 1.67% to 95.00% (B) and 15.00% to 98.33% (L) in major workers. The volatile compounds were also found to exert a behavioral effect against S. invicta in an A4 paper test. Walking and grasping abilities decreased at exposure times ranging from 40 min to 280 min. These findings suggest that the volatile compounds of T. vogelii can be used to control S. invicta

Competition and cooperation of sulfate reducing bacteria and five other bacteria during oil production

Embargo until March 18, 2023Effective control of sulfate-reducing bacteria (SRB) will help reduce economic losses and prevent threats to human health during the oil production. In this study, the responses of SRB to environmental variables and some functional microorganisms (including denitrifying bacteria (DNB), methanogenic bacteria (MGB), saprophytic bacteria (SPB), zymophyte bacteria (ZPB), and iron bacteria (IB)), during oil production processes were investigated to improve our understanding of how to control SRB abundance. Correlation analyses demonstrated that nitrate and redox potential exihibited significant inhibitory effects on the growth and reproduction of SRB and redox potential (0.175, P < 0.01) had a stronger effect than NO3− (0.0817, P < 0.05). PCA analysis demonstrated a clear division of the bacteria into two clusters, cluster 1 consisted of SRB, SPB and IB, while cluster 2 consisted of DNB, MGB and ZPB. Cooperation was apparent for SRB with SPB and IB, while competition was apparent for SRB with DNB, MGB and ZPB. These results provide new insights to possible solutions to control SRB growth in the oilfield environment, including addition of nitrate and nitrite, to promote the growth of denitrifying bacteria, thereby suppressing the growth of SRB.acceptedVersio