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Purpose This paper aims to investigate the high-temperature mechanical properties of HS110S steel and its corrosion behaviors in harsh downhole environment. Design/methodology/approach In this work, mechanical property measurements were carried out from 25°C to 350°C and the scanning electron microscopy was used to observe the fracture morphology. The weight-loss measurements and surface characterization were used to evaluate the corrosion resistance of HS110S steel in harsh downhole environment. Findings Results show that the yield strength and tensile strength of HS110S steel at 350 °C are 779 and 861 MPa, respectively. Compared with room temperature, the reduction rate values are both less than 20%. At the high-temperature corrosion environment (350 °C), the static and dynamic corrosion rates are 0.9668 and 1.9236 mm/a, respectively. The generated corrosion products are mainly composed of FeSx, FeCO3 and Fe3O4. Therefore, the HS110S steel applied under such conditions needs to take suitable protective measures. Originality/value In general, the HS110 steel has widely used in conventional development conditions (e.g. low H2S or high CO2 environments). However, to the best of the authors’ knowledge, no studies have reported on its application at more than 250°C. Therefore, this work can be a reference to the application of HS110S steel in high-temperature corrosion conditions.

The involvement of genetic risk and the underlying developmental and neural circuit mechanisms in autism-related social deficit are largely unclear. Here, we report that deletion of AUTS2 , a high-susceptibility gene of ASDs, caused postnatal dentate gyrus (DG) hypoplasia, which was closely relevant to social recognition deficit. Furthermore, a previously unknown mechanism for neural cell migration in postnatal DG development was identified, in which Auts2-related signaling played a vital role as the transcription repressor. Moreover, the supramammillary nucleus (SuM)–DG-CA3 neural circuit was found to be involved in social recognition and affected in Auts2 -deleted mice due to DG hypoplasia. Correction of DG-CA3 synaptic transmission by using a pharmacological approach or chemo/optogenetic activation of the SuM-DG circuit restored the social recognition deficit in Auts2 -deleted mice. Our findings demonstrated the vital role of Auts2 in postnatal DG development, and this role was critical for SuM-DG-CA3 neural circuit-mediated social recognition behavior.

Autism spectrum disorders (ASDs) are a group of highly inheritable neurodevelopmental disorders. Functional mutations in TRIO, especially in the GEF1 domain, are strongly implicated in ASDs, whereas the underlying neurobiological pathogenesis and molecular mechanisms remain to be clarified. Here we characterize the abnormal morphology and behavior of embryonic migratory interneurons (INs) upon Trio deficiency or GEF1 mutation in mice, which are mediated by the Trio GEF1-Rac1 activation and involved in SDF1α/CXCR4 signaling. In addition, the migration deficits are specifically associated with altered neural microcircuit, decreased inhibitory neurotransmission, and autism-like behaviors, which are reminiscent of some features observed in patients with ASDs. Furthermore, restoring the excitatory/inhibitory (E/I) imbalance via activation of GABA signaling rescues autism-like deficits. Our findings demonstrate a critical role of Trio GEF1 mediated signaling in IN migration and E/I balance, which are related to autism-related behavioral phenotypes.

To evaluate the property of the organic coatings in oil and gas plants, the aging process was studied in high temperature and high CO2 partial pressure environment. Correlations were developed between the macroscopic properties and microstructure of the organic coatings. The surface appearance, mechanical properties, and permeability of the organic coatings were measured. Furthermore, the crystal structure of the organic coatings was investigated through synchrotron radiation grazing incidence X-ray diffraction (GIXRD) on the BL14B1 beam line in Shanghai Synchrotron Radiation Facility. Combined with the Fourier transform infrared spectroscopy, the molecular structure of the organic coatings was investigated. The experimental results indicate that the thickness variation and weight loss of the organic coatings increase with the immersion time, and the penetration resistance of the coating obviously decreases as the temperature rises. Moreover, the degradation of the organic coatings with immersion time in high temperature and high CO2 partial pressure environment is caused by the amorphization of the organic coatings as the groups and bonds of the organic coatings were not damaged.

Accumulating evidence suggest that excessive reactive oxygen species-induced oxidative damage may underlie neurodegeneration and cognitive impairment in several disorders including schizophrenia. In this study we examined the association of oxidative stress with cognitive deficits in first-episode drug-naive (FEDN) patients with schizophrenia. We recruited 54 FEDN patients and 50 age- and sex-matched healthy controls and examined the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus cognitive Battery (MCCB) and plasma total antioxidant status (TAS). Psychopathological symptoms were assessed using the Positive and Negative Syndrome Scale. The results showed that plasma TAS levels were significantly lower in the patients than those in the healthy subjects (94.7 ± 25.0 U/ml vs 156.6 ± 46.7 U/ml, p

Neuronal polarity is involved in multiple developmental stages, including cortical neuron migration, multipolar-to-bipolar transition, axon initiation, apical/basal dendrite differentiation, and spine formation. All of these processes are associated with the cytoskeleton and are regulated by precise timing and by controlling gene expression. The P-Rex1 (phosphatidylinositol-3,4,5-trisphosphate dependent Rac exchange factor 1) gene for example, is known to be important for cytoskeletal reorganization, cell motility, and migration. Deficiency of P-Rex1 protein leads to abnormal neuronal migration and synaptic plasticity, as well as autism-related behaviors. Nonetheless, the effects of P-Rex1 overexpression on neuronal development and higher brain functions remain unclear. In the present study, we explored the effect of P-Rex1 overexpression on cerebral development and psychosis-related behaviors in mice. In utero electroporation at embryonic day 14.5 was used to assess the influence of P-Rex1 overexpression on cell polarity and migration. Primary neuron culture was used to explore the effects of P-Rex1 overexpression on neuritogenesis and spine morphology. In addition, P-Rex1 overexpression in the medial prefrontal cortex (mPFC) of mice was used to assess psychosis-related behaviors. We found that P-Rex1 overexpression led to aberrant polarity and inhibited the multipolar-to-bipolar transition, leading to abnormal neuronal migration. In addition, P-Rex1 overexpression affected the early development of neurons, manifested as abnormal neurite initiation with cytoskeleton change, reduced the axon length and dendritic complexity, and caused excessive lamellipodia in primary neuronal culture. Moreover, P-Rex1 overexpression decreased the density of spines with increased height, width, and head area in vitro and in vivo. Behavioral tests showed that P-Rex1 overexpression in the mouse mPFC caused anxiety-like behaviors and a sensorimotor gating deficit. The appropriate P-Rex1 level plays a critical role in the developing cerebral cortex and excessive P-Rex1 might be related to psychosis-related behaviors. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12264-019-00408-2) contains supplementary material, which is available to authorized users.

Pitting corrosion of carbon steel in sodium chloride solution induced by Ce[Formula: see text] and the synergistic inhibition effects of Ce[Formula: see text] and Zn[Formula: see text]/SiO[Formula: see text] were investigated using in-situ observation and electrochemical methods. The results showed that the presence of Ce[Formula: see text] could result in severe pitting corrosion and a positive shift in the corrosion potential. It was found that individual Ce[Formula: see text], Zn[Formula: see text], or SiO[Formula: see text] had low inhibition efficiencies, whereas the combination of Ce[Formula: see text] and Zn[Formula: see text] or SiO[Formula: see text] proved to be highly effective in inhibiting the development of pits in two different ways and in enhancing the corrosion resistance. The pitting corrosion and inhibition mechanisms were discussed based on the results.

Summary: Previous genetic and biological evidence converge on the involvement of synaptic dysfunction in schizophrenia, and OPCML, encoding a synaptic membrane protein, is reported to be genetically associated with schizophrenia. However, its role in the pathophysiology of schizophrenia remains largely unknown. Here, we found that Opcml is strongly expressed in the mouse hippocampus; ablation of Opcml leads to reduced phosphorylated cofilin and dysregulated F-actin dynamics, which disturbs the spine maturation. Furthermore, Opcml interacts with EphB2 to control the stability of spines by regulating the ephrin-EphB2-cofilin signaling pathway. Opcml-deficient mice display impaired cognitive behaviors and abnormal sensorimotor gating, which are similar to features in neuropsychiatric disorders such as schizophrenia. Notably, the administration of aripiprazole partially restores the abnormal behaviors in Opcml−/− mice by increasing the phosphorylated cofilin level and facilitating spine maturation. We demonstrated a critical role of the schizophrenia-susceptible gene OPCML in spine maturation and cognitive behaviors via regulating the ephrin-EphB2-cofilin signaling pathway, providing further insights into the characteristics of schizophrenia. : Zhang et al. investigate the mechanism of the schizophrenia-associated opioid-binding protein/cell adhesion molecule (OPCML) in spine maturation and its role in general cognitive function using an Opcml-deficient mouse model. Opcml mediates postsynaptic ephrin-EphB2-cofilin signaling in the regulation of spine maturation, which is involved in the pathogenic mechanism of neurodevelopmental disorders such as schizophrenia. Keywords: schizophrenia, OPCML, spine maturation, cofilin, EphB2 signaling, aripiprazole, cognition

The influence of formic acid on the CO2 corrosion of the 20# steel in the formation water was studied, via corrosion immersion experiments using formation water as corrosion medium. The morphology of the corrosion products was observed with SEM, and the electrochemistry performance of the corrosion products was analyzed with EIS. The results indicated that the formic acid can accelerate corrosion of 20# steel. Corrosion rate increases with addition of formic acid in the solution. When the content of formic acid was 40 ppm and 100 ppm, uniform corrosion was observed. Simultaneously, shallow pits appeared on the surface. As the content of formic acid rose to 500 ppm, pitting corrosion was much likely to occur. With the extension of corrosion time, the results of EIS tests showed that with addition of formic acid at 40 ppm and 100 ppm, the graph contains a high-frequency capacitive reactance and low-frequency inductive reactance trend, then convert to double capacitive reactance with increase of immersion time. And when the content of formic acid increased to 500 ppm, double capacitive reactance was found in EIS pattern, and then convert to high-frequency capacitive reactance, mid-frequency inductive reactance and low-frequency inductive reactance with increase of immersion time.

The feasibility and reliability of ultrasonic monitoring system for pipeline corrosion in oil and gas field based on Ultrasonic monitoring technology has been researched in this paper. The results show that the ultrasonic monitoring system can implement accurate corrosion and thickness monitoring for key points of key pipeline. Multi-crystal ultrasonic wave sensor is used to monitor thickness of key points in circumferential direction, and the big errors and mistakes caused by traditional monitoring methods can be avoided. A laboratory demo of monitoring system has demonstrated that the test results have the characteristic of repeatability and accuracy.

This paper discussed the corrosion characters and new double layers metal thermal spary technology for gas well tubing in Erdos basin, Changqing field. Some gas wells produce formation brine, also contain low H2S content and medium CO2 content. (water/gas ratio lager than 0.2m3/104m3, and averge total ions strength is 120g/L, Cl− nearly 80g/L). The electric-chemical corrosion causes the workover lifetime of gas well less than 5 years. On the external surface of SSC-resistant carbon steel (80S) tubing, the double metals protection layers of 13Cr and Aluminum were designed and applied by high speed arc spary technology. Physical and corrosive properties were researched at simulation and HT/HP conditions. More than 15 wells were applied by this method in recently 4 years. Before workovering, the lifetime of those wells were not more than 5 years, also lower than regulation workover time of 8 years. At 4 years ago, the corrosion situations of 3 wells which would be workovered were inspected using the multifinger imaging tool and magnetic thickness tool, MID-K logging equipments. By now, those wells were logged (MIT+MTT) again and showing a good condition.

With the increasing oil production of Changqing oilfield, the casing's corrosion and damage have became more and more serious in producing and injection well system. After long term research, the corrosion mechanisms of casing were made sure, and two main technologies were developed to prevent the external and internal corrosion, respectively (Cluster wells’ CP and Epoxyn-bond tape plus zinc anode, Inner polymer coating and Downhole inhibitor injection facility). Three types of control technologies of well damage casing have been applied. The large scale applications of those technologies in Changqing oilfield not only inhibit the casing's damaged, and also keep the newly opened wells in a good condition. At last these new techniques guarantee the stable production of Changqing oilfield.