Ameliorative activity of medicinal plant fraction for neuroprotection against acrylamide-induced neurotoxicity in Drosophila melanogaster—a comparative study

Background Medicinal plant extracts used in folk medicine seem to be crucial since those are generally accepted by people without worrying about the toxicity. In our present study, we have compared the neuroprotective role of the rhizome of Curculigo orchioides Gaertn. and leaf extracts of Olea dioica Roxb., against acrylamide-induced neurotoxicity in Drosophila melanogaster. Results In-vivo neurotoxic study was carried out using 7-day-old flies (wild-type D. melanogaster). Prior to co-after exposing the flies with acrylamide (8 mM) along with or without OLE-2 and CU-3 fractions (0.2, 0.4 and 0.6% w/v), the heads of flies of both the control and treated groups were homogenized for biochemical assay. ACR-treated groups have shown higher elevation in AChE, SOD, LPO, and CAT activity when compared to control and treated (plant fraction) groups. Biochemical and histopathology studies show that both the plant fractions (OLE-2 and CU-3) have neuroprotective action against acrylamide. Conclusion The present study has demonstrated that dietary supplementation with plant fraction of OLE-2 and CU-3 has increased antioxidant enzymes and decreased AChE activity in D. melanogaster. This activity could be part of the probable mechanisms of action by which OLE-2 and CU-3 fractions have extended the lifespan and locomotory activity in fruit flies. These fruit flies continue to provide an exciting system for metabolic studies and should be more extensively exploited. Based on these results, further studies on the identified bioactive compounds from these two plants are being planned.

New opportunities and insights into Papaver self-incompatibility by imaging engineered Arabidopsis pollen

Pollen tube growth is essential for plant reproduction. Their rapid extension using polarized tip growth provides an exciting system for studying this specialized type of growth. Self-incompatibility (SI) is a genetically controlled mechanism to prevent self-fertilization. Mechanistically, one of the best-studied SI systems is that of Papaver rhoeas (poppy). This utilizes two S-determinants: stigma-expressed PrsS and pollen-expressed PrpS. Interaction of cognate PrpS–PrsS triggers a signalling network, causing rapid growth arrest and programmed cell death (PCD) in incompatible pollen. We previously demonstrated that transgenic Arabidopsis thaliana pollen expressing PrpS–green fluorescent protein (GFP) can respond to Papaver PrsS with remarkably similar responses to those observed in incompatible Papaver pollen. Here we describe recent advances using these transgenic plants combined with genetically encoded fluorescent probes to monitor SI-induced cellular alterations, including cytosolic calcium, pH, the actin cytoskeleton, clathrin-mediated endocytosis (CME), and the vacuole. This approach has allowed us to study the SI response in depth, using multiparameter live-cell imaging approaches that were not possible in Papaver. This lays the foundations for new opportunities to elucidate key mechanisms involved in SI. Here we establish that CME is disrupted in self-incompatible pollen. Moreover, we reveal new detailed information about F-actin remodelling in pollen tubes after SI.

First-Principles Calculations of Point Defects for Quantum Technologies

Point defects in semiconductors and insulators form an exciting system for realizing quantum technologies, including quantum computing, communication, and metrology. Defects provide a platform that combines the environmental isolation necessary to maintain the coherence of quantum states with the ability to perform electrical and optical manipulation. First-principles calculations play a crucial role in identifying, characterizing, and developing defects for quantum applications. We review the first-principles methodologies for calculating the relevant structural, electronic, vibrational, optical, and magnetic properties of defects for quantum technologies. We illustrate the utility and accuracy of these techniques by using examples from the literature. We also point out areas in which further development of the computational techniques is desirable.

Improvement of Sensitivity and Detectability of the Three-Coil Wear Debris Detection Sensor Using LC Resonance Method and Modified Lock-in Amplifier

That how to improve the sensitivity and the detection ability of the Large-caliber sensor is critical to satisfy the requirement of heavy vehicle wear condition monitoring. In this paper, we introduced the LC resonance principle to the design of sensor with large flow channel (7mm). The resonant exciting coil increases the impedance change of the exciting circuit caused by wear particles which magnify the current difference between the two exciting coils and improve the sensitivity of the sensor. The resonant induction coil greatly suppresses the interference signals and magnifies the weak induced electromotive force which is beneficial to enhance the detection ability. In order to boost the detectability for different materials particles, a phase controlled variable-frequency exciting system (PCVFES) was adopted to automatically switch the exciting frequency between 284kHz for ferromagnetic particles and 420KHz for non-ferromagnetic particles. For the weak signal detection, based on the essential characteristic of the signal, we apply a simpler method that modified lock-in amplifier (MLIA) rather than the conventional algorithms (Wavelet transform, EMD). Results show that using these methods the sensitivity and the detection ability of the sensor are significantly improved and the 75μm iron particles and 220μm copper particles were successfully detected which realizes the initial abnormal wear monitoring for the large flow project.

Dynamic Model and Vibration Power Flow of a Rigid-Flexible Coupling and Harmonic-Disturbance Exciting System for Flexible Robotic Manipulator with Elastic Joints

This paper investigates the dynamic of a flexible robotic manipulator (FRM) which consists of rigid driving base, flexible links, and flexible joints. With considering the motion fluctuations caused by the coupling effect, such as the motor parameters and mechanism inertias, as harmonic disturbances, the system investigated in this paper remains a parametrically excited system. An elastic restraint model of the FRM with elastic joints (FRMEJ) is proposed, which considers the elastic properties of the connecting joints between the flexible arm and the driving base, as well as the harmonic disturbances aroused by the electromechanical coupling effect. As a consequence, the FRMEJ accordingly remains a flexible multibody system which conveys the effects of rigid-flexible couple and electromechanical couple. The Lagrangian function and Hamilton’s principle are used to establish the dynamic model of the FRMEJ. Based on the dynamic model proposed, the vibration power flow is introduced to show the vibration energy distribution. Numerical simulations are conducted to investigate the effect of the joint elasticities and the disturbance excitations, and the influences of the structure parameters and motion parameters on the vibration power flow are studied. The results obtained in this paper contribute to the structure design, motion optimization, and vibration control of FRMs.

Reform of Excitation System on the Domestic 600MW Subcritical Turbine Generator Unit

Analog Excitation regulation system is applied in No.3 turbine generator unit of Harbin No.3 power plant, Huadian Energy Group, and the system has several problems such as high failure rate, poor regulating performance and low level automation. As a solution, the static self-shunt excitation system is used to replace the analog excitation regulation system, UNITROL 5000 all-digital excitation system is adopted. With specific field situation, the paper introduces the structure and application of the system in details. Compared with the conventional A.C. exciting system, the all-digital excitation system has effectively improved the stability and reliability of the generator, with the advantages of more flexibility of the start-up modes and undisturbed switching. It is also reliable and convenient for the switching of PSS additional regulation unit.