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Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease. The cannula insertion process plays an important role in DBS. The friction force during needle insertion influences the precision of the insertion and the degree of damage to the brain tissue. This paper proposes a method of longitudinal vibration assisted insertion to reduce the friction during insertion and improve the effects of the insertion. Cannulas were inserted into twenty eight pig brains at multiple frequencies and fixed amplitudes, and the resulting friction force was measured. On this basis, the LuGre model was used to analyze the friction force trend under vibration-assisted conditions. The frictional forces of vibration-assisted insertion with frequencies ranging from 200–1200 Hz and an amplitude of 1 μm were measured. The results show that the friction between the needle shaft and the tissue is smaller with vibration than without vibration. In this experiment, the friction is reduced by up to 24.43%. The friction force trend of vibration-assisted insertion conforms to the simulation results of the LuGre model.

The commonly used fault diagnosis method of the power transmission line (PTL) is the traveling wave method which uses the traditional mode components $$\alpha $$ , $$\beta $$ and o to realize the fault type recognizing and the fault location in distribution network. However, the traditional mode components of the traveling wave method may take the value of zero that cannot provide the effective fault feature for the A-phase ground fault, or the A and B double phases short-circuit fault. Moreover, a single traditional mode component cannot recognize all the types of the faults, and the fault recognition has to use the multiple mode components that increases the complexity. To address the aforementioned issues, this paper proposes an edge computing scheme based on a novel mode component $$\gamma $$ for PTL fault diagnosis in distribution network. Firstly, the novel mode component $$\gamma $$ is fused according to the traditional mode components $$\alpha $$ and $$\beta $$ , then the propagation property of the traveling wave- $$\gamma $$ is derived. Secondly, the edge computing scheme and the PTL fault diagnosis method are designed for distribution network by using the only novel mode component $$\gamma $$ . Thirdly, the relationship table of the fault type and the boundary conditions as well as the component $$\gamma $$ expressions is derived for the fault recognition using the only traveling wave- $$\gamma $$ . In addition, the fault distance computing is explored by using the traveling wave- $$\gamma $$ . The computing is composed with the wave- $$\gamma $$ head identification using the optimal Wavelet vanishing moment parameter, and the arrival time determination, and the fault location method. To evaluate the efficiency of the proposed edge computing scheme, the simulation experiment and the laboratory tests are conducted. The simulation experiment results show that, the novel mode component $$\gamma $$ not only provides the effective fault features for all the ten types of the power transmission line faults, but also increases fault locating accuracy by the average 2.08 % compared with the methods using the traditional mode component $$\alpha $$ , $$\beta $$ and o. Meanwhile, the laboratory tests show that the edge computing method is practical.

Previous research has found that a negative life event is a main risk factor for hopelessness, which in turn is considered to be a proximal cause of major depression disorder and a suicide risk factor. Unfortunately, very little attention has been paid to the role of decision-making constructs between negative life events and hopelessness. To fill this gap, the present study aims to test the moderation role of sunk cost propensity in this relationship, which is an over-generalized tendency to persist, based on past investment. A total of 495 university students completed assessment of their resistance to sunk cost propensity, whereas the negative life events, hopelessness, mental health state (depression, anxiety) and big-five personality traits were measured by various questionnaires. Participants’ tendency to resist sunk cost propensity moderated the relationship between negative life events and hopelessness. Individuals who tended to resist sunk cost bias are more vulnerable to the adverse effects of negative life events. This effect is still significant, even after controlling for individuals’ psychological well-being (depression, anxiety) and big-five personality traits. The current findings provide preliminary evidence that resistance to sunk cost propensity may be an important characteristic associated with an individual’s hopelessness when exposed to a negative life event.

Deep brain stimulation (DBS) is an effective treatment for Parkinson's disease. The insertion of brain tissue is an important procedure that affects the whole operation and the sequela. During the insertion process, the friction between the tissue and the needle shaft is the main factor affecting the degree of tissue damage and the accuracy of target location. Vibration-assisted needle insertion has been shown to reduce friction during needle insertion into biological tissue. LuGre model is a friction model that includes coulomb friction and viscous friction between two contact surfaces and accurately describes the Stribeck effect. This paper studies the influence of longitudinal vibration on the friction force during needle insertion. Based on LuGre model, the influence of longitudinal vibration parameters on friction force is discussed. Through experiments on porcine brain tissue and gel phantom, the friction force during insertion and the positive pressure of tissue against the needle under different vibration parameters were investigated. The experiment showed that the vibration can change the friction force by affecting the equivalent friction coefficient and the positive pressure of tissue against the needle. The equivalent friction coefficient showed a specific trend with the change of vibration parameters, while the positive pressure does not change with the vibration parameters.

Polypyrrole–polydopamine (PPy–PDA) coatings were fabricated on the surface of tungsten substrates based on fusion two different methods, electropolymerization and auto-polymerization, and ZnO nanoparticles (NPs) were simultaneously introduced to alleviate the mechanical mismatch between the brain tissue and conductive coating. The effects of ZnO NPs on microstructure, mechanical properties, adhesion strength, conductivity, and wettability of the nanocomposite coatings were systematically investigated. It resulted that the amorphous diffraction characteristics of PPy matrix polymer were not changed after adding ZnO NPs. However, the deposited rate of the coating was increased and the structure became coarser and porous. With the increasing concentration of NPs in electrolyte, ranging from 0 to 0.7 g/L, the elastic modulus and nano-hardness of the coating effectively reduced by 57% and 63%, respectively. However, the conductivity and adhesion strength were also decreased to a certain degree. Additionally, although the wettability of the PPy matrix polymer was limitedly influenced by the incorporation of ZnO NPs, it could be improved by 2~38% with the modification of PDA nano-film.

Three monochlorobenzoate isomer-utilizing bacterial strains, Pseudomonas sp. 2-CBA, Pseudomonas sp. 3-CBA, and Hydrogenophaga sp. 4-CBA, were isolated from a haloaromatic-contaminated soil in a disused chemical factory in Nanjing, China. Compared to strain 3-CBA and strain 4-CBA, which could only utilize its corresponding monochlorobenzoate isomer (3-chlorobenzoate and 4-chlorobenzoate) as the sole carbon source for growth, strain 2-CBA could utilize both 2-chlorobenzoate and 3-chlorobenzoate for growth. The three monochlorobenzoate isomers were catabolized via three different dechlorination pathways in the three isolates, respectively. 3-Chlorobenzoate was initially catabolized by the benzoate 1,2-dioxygenase (BenABCD) in strain 3-CBA, whereas 2-chlorobenzoate was catabolized by the hybrid 2-halobenzoate 1,2-dioxygenase system in strain 2-CBA, which comprised of the terminal oxygenase component of 2-halobenzoate dioxygenase system (CbdAB) and the reductase component of benzoate 1,2-dioxygenase system (BenC). For 4-chlorobenzoate, it was catabolized via the classic hydrolytic dehalogenation pathway in strain 4-CBA. While, strain 4-CBA seemed to have a more compact gene cluster of fcbABC compared to previously reported strains. This study provides new insights into the catabolic diversity of structurally similar isomers in a contaminated niche.

An aerobic, Gram-stain negative, short rod-shaped, asporogenous, non-motile bacterium designated strain NK8T was isolated from a chlorobenzoate contaminated soil in China. Strain NK8T was observed to grow optimally at pH 7.0, 30 °C and in the absence of NaCl in LB medium. The G + C content of the total DNA of strain NK8T was found to be 65.5 mol%. The 16S rRNA gene sequence of strain NK8T showed high similarity to that of Aquamicrobium aerolatum Sa14T (97.3%), followed by Aquamicrobium lusatiense S1T (96.7%) and Mesorhizobium sangali SCAU7T (96.6%). The DNA–DNA relatedness between strain NK8T and A. aerolatum Sa14T was 35.5 ± 0.9%. The major fatty acids of strain NK8T were determined to be C19:0 cyclo ω8c (45.6%), C18:1 ω7c (33.4%) and C16:0 (8.4%). The respiratory quinone was found to be ubiquinone Q-10. The major polyamine was found to be spermidine. The polar lipid profile include the major compounds phosphatidylcholine and diphosphatidylglycerol, and moderate amounts of phosphatidylethanolamine, phosphatidylmonomethylethanolamine, aminolipid and phospholipid. Based on the differential biochemical and physiological characteristics, the geno-, chemo- and phenotypic characteristics, strain NK8T is proposed to represent a novel species of the genus Aquamicrobium, Aquamicrobium soli sp. nov. The type strain is NK8T (=KCTC 52165T=CCTCC AB2016045T).

Microbial dehalogenation plays key roles in the biodegradation and detoxification of halogenated aromatics. Although the hydrolytic dehalogenation of halogenated aliphatic hydrocarbons and carboxylic acids has been extensively studied, there are few reports on the hydrolytic dehalogenation of halogenated aromatics. In this study, the aerobic strain BSQ-1, isolated from soils contaminated with halogenated aromatics in Jiangsu, China, was able to completely degrade 0.12 mM o -tetrachlorophthalonitrile in 84 h in the presence of 2 mM sodium acetate trihydrate and released one equivalent of chlorine ions. MS–MS and NMR analysis revealed that o -tetrachlorophthalonitrile was dehalogenated to 4-hydroxyl- o -trichlorophthalonitrile. The dehalogenation of o -tetrachlorophthalonitrile could occur under both aerobic and anaerobic conditions, showing that the observed dehalogenation was a hydrolytic process. The optimal temperature and pH for o -tetrachlorophthalonitrile dehalogenation by strain BSQ-1 were 30 °C and 8, respectively. It was found that 0.2 mM Zn 2+ , Mg 2+ or Co 2+ enhanced dehalogenation activity, whereas 0.2 mM Fe 3+ , Ni 2+ , Cu 2+ , Ca 2+ , or Pb 2+ inhibited dehalogenation activity. Strain BSQ-1 was able to dehalogenate not only o -tetrachlorophthalonitrile but also its two isomers, chlorothalonil and p -tetrachlorophthalonitrile. This study presents a new example of the hydrolytic dehalogenation of halogenated aromatics by microorganisms and provides a good candidate strain for the clean-up of tetrachlorophthalonitrile-contaminated sites.

To eliminating the influence of traveling wave velocity on the fault location accuracy of the power line, a fault location method without wave velocity influence using Wavelet and Clark transform is developed in this paper. On the basis of the reflection characteristic analysis of fault traveling wave, the aerial mode component of the voltage traveling wave is obtained by Clark transform. Then, the fault time when the first three mode maximum appear on the measuring end is determined by the combination of the aerial mode component with Wavelet transform. Furthermore, a set of equations that is composed by the fault time and the fault distance is formed. This method is independent of the wave velocity and is not affected by the traveling wave velocity theoretically. The simulation results show that the developed method can reduce the relative error of the fault distance by less than 5%, which proves the validity and the accuracy of this method.

Dehalogenation is the key step in the degradation of halogenated aromatics, while reductive dehalogenation is originally thought to rarely occur in aerobes. In this study, an aerobic strain of Comamonas sp. 7D-2 was shown to degrade the brominated aromatic herbicide bromoxynil completely and release two equivalents of bromides under aerobic conditions. The enzymes involved in the degradation of bromoxynil to 4-carboxy-2-hydroxymuconate-6-semialdehyde, including nitrilase, reductive dehalogenase (BhbA), 4-hydroxybenzoate 3-monooxygenase and protocatechuate 4,5-dioxygenase, were molecularly characterized. The novel dehalogenase BhbA was shown to be a complex of a respiration-linked reductive dehalogenase (RdhA) domain and a NAD(P)H-dependent oxidoreductase domain and to have key features of anaerobic respiratory RdhAs, including two predicted binding motifs for [4Fe-4S] clusters and a close association with a hydrophobic membrane protein (BhbB). BhbB was confirmed to anchor BhbA to the membrane. BhbA was partially purified and found to use NAD(P)H as electron donors. Full-length bhbA homologues were found almost exclusively in marine aerobic proteobacteria, suggesting that reductive dehalogenation occurs extensively in aerobes and that bhbA is horizontally transferred from marine microorganisms. The discovery of a functional reductive dehalogenase and ring-cleavage oxygenases in an aerobe opens up possibilities for basic research as well as the potential application for bioremediation.

This text is based on the understand of electric voltage, wattless influence to the supply of electric power system, and the shortage realize of traditional nine area diagrams of electric power system, A new fuzzy controller wattless compensate method put forward to compensate wattlessement, the control's method can follow and predict the variety of electric voltage, at attain a control target of at the same time, can availably reduce have already carried to adjust to press transformer to deal with contact for cent of regulate number of times.