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Dichlorvos (DDVP) is an insecticide with neurotoxicity that is widely used in agricultural production and life. However, the effects of acute DDVP poisoning on brain tissue remain underinvestigated. The purpose of this study was to evaluate the differences within 15 min-6 h in plasma biochemical indexes, brain histology and metabolites among three groups of commercial broilers orally administered different dosages of DDVP one time: (1) high-dose group (11.3 mg/kg), (2) low-dose group (2.48 mg/kg) and (3) control group (0 mg/kg). The results of biochemical indexes showed that acute DDVP poisoning could cause hyperglycemia and oxidative stress in poisoned broilers. Histological examination showed that DDVP could induce brain edema, abnormal expression of glial fibrillary acidic protein (GFAP) and neuronal mitochondrial damage in broilers. Whole-brain metabolism showed that DDVP could significantly change the secretion of neurotransmitters, energy metabolism, amino acid metabolism and nucleotide metabolism. Correlation analysis showed that metabolites such as hypoxanthine, acetylcarnitine and glucose 6-phosphate were significantly correlated with blood glucose, biomarkers of oxidative stress and brain injury pathology. The results of this study provide new insights into the molecular mechanism of brain tissue responses to acute DDVP exposure in broilers and deliver important information for clinical research on neurodegenerative diseases caused by acute DDVP poisoning.

The high-temperature gas-cooled reactor-pebble bed module (HTR-PM) has been proposed by the Institute of Nuclear and New Energy Technology of Tsinghua University. The helium circulator is equipped in the primary loop of HTR-PM to drive high-temperature helium for energy exchange. The active magnetic bearing (AMB), replaced by the ordinary mechanical bearing, is chosen as the perfect supporting scheme for the helium circulator of HTR-PM. Additionally, the auxiliary bearing is applied in case of AMB failures and has become indispensable to provide mechanical supports and displacement constraints for the rotor. When the rotor drops down, the auxiliary bearing needs to sustain fierce impacts and corresponding thermal growth. While due to the special environment in the primary loop of HTR-PM, oil or grease lubrication can’t be applied in the auxiliary bearing. A new design of unlubricated auxiliary bearing is proposed in this paper. This paper mainly deals with the following two aspects to reveal the rotor drop: dynamic analysis including fatigue life prediction, and corresponding thermal growth. Moreover, dropping experiments are carried out in the HTR-PM helium circulator system. The experimental results can verify the auxiliary bearing capacity to endure the dynamic impact of the dropping rotor, and provide suggestions for the auxiliary bearing type selection. The results in this paper will provide theoretical suggestions for further engineering design and application of the auxiliary bearing in the helium circulator of HTR-PM.

The purpose of this study was to discuss the effects of N-acetyl-l-cysteine (NAC) on heat stress-induced oxidative stress and inflammation in the hypothalamus of hens in different periods. A total of 120 Hy-Line variety brown laying hens (12 weeks old) were randomly assigned to 4 groups with 6 replicates. The control group (C group) (22 ± 1 °C) received a basal diet, the NAC-treated group (N group) (22 ± 1 °C) received a basal diet with 1000 mg/kg NAC, and 2 heat-stressed groups (36 ± 1 °C for 10 h per day and 22 ± 1 °C for the remaining time) were fed a basal diet (HS group) or a basal diet with 1000 mg/kg NAC (HS + N group) for 21 consecutive days. The influence of NAC on histologic changes, oxidative stress and proinflammatory cytokine production was measured and analysed in hens with heat stress-induced hypothalamic changes. NAC effectively alleviated the hypothalamic morphological changes induced by heat stress. In addition, NAC attenuated the activity of the Nf-κB pathway activated by heat stress and decreased the expression of the proinflammatory cytokines IL-6, IL-18, TNF-α, IKK, and IFN-γ. In addition, NAC treatment regulated the expression of HO-1, GSH, SOD2 and PRDX3 by regulating the activity of Nrf2 at different time points to resist oxidative stress caused by heat exposure. In summary, dietary NAC may be an effective candidate for the treatment and prevention of heat stress-induced hypothalamus injury by preventing Nf-κB activation and controlling the Nrf2 pathway.

Summary The relationship between insomnia and hypertension remains inconclusive. Thus, we conducted a meta-analysis of prospective cohort studies to evaluate the association between insomnia and the risk of hypertension. Relevant prospective cohort studies were searched from PubMed, Embase, and Web of Science from their inception to October 2019. A random-effects model was used to calculate the pooled relative risk (RR) with 95% confidence interval (CI). A total of fourteen prospective cohort studies involving 395,641 participants were included in this study. The pooled RR of insomnia on hypertension was 1.21 (95%CI: 1.10–1.33). An increased risk of hypertension was observed in participants with difficulty maintaining sleep (RR = 1.27; 95%CI: 1.04–1.55) and early morning awakening (RR = 1.14; 95%CI: 1.08–1.20), but was not statistically significant in participants with difficulty falling asleep (RR = 1.14; 95%CI: 0.95–1.37). In addition, the results were statistically significant in the European population (RR = 1.08, 95%CI: 1.02–1.14), but not significant in Asian and American populations (RR = 1.54, 95%CI: 0.98–2.40; RR = 1.21, 95%CI: 0.89–1.65). The study findings indicate that insomnia is associated with a significantly increased risk of hypertension. This may have substantial implications for the prevention of hypertension in individuals with insomnia symptoms.

The 10 MW high-temperature gas-cooled reactor (HTR-10) was constructed by the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University. The auxiliary bearing is utilized in this system to meet particular requirements for the reactor. The main role of the auxiliary bearing is to constrain rotor displacements and also to support the rotor when the rotor drops down, which is caused by the active magnetic bearing (AMB) failure. The auxiliary bearing needs to endure huge impact, rapid angular acceleration and thermal shock. On the one hand, complex geometrical constructions and forces applied on the system bring difficulties and restrictions to establish an appropriate model to reveal the actual dynamic process. On the other hand, large volumes of data obtained from experiments show velocities and displacements of the rotor during the rotor drop process and then can indicate the actual dynamic interactions to a great extent. The research in this paper is based on the test rig of the AMB helium circulator of HTR-10. This paper aims to analyze the dynamic performance and contact forces of the rotor by processing experimental data. A measurement to estimate forces developed due to impacts of the rotor and the auxiliary bearings is presented. It is of great significance and provides certain foundation to elaborate the rotor drop process for the AMB helium circulator of HTR-10.

The Active Magnetic Bearing (AMB) is used in the High Temperature Reactor- Pebble-bed Modules (HTR-PM) which is being constructed in Shandong province, China. The auxiliary bearing is one of the most important components guaranteeing the reliability of the AMB. A novel rolling-sliding integrated auxiliary bearing is studied through the drop experiment. For comparison, a traditional rolling auxiliary bearing in the same AMB is also studied experimentally. It was found that the rotor center orbit with the novel auxiliary bearing is much simpler and more focused. The impact force with the novel auxiliary bearing during the drop is much less. The drop process with the novel auxiliary bearing is more stable. All these phenomena are due to the fact that the contact point of the rotor with the novel auxiliary bearing is easy to stay at the lowest position of the circular contact surface during drop process.

Long noncoding RNAs (lncRNAs) comprise RNA transcripts that exceed 200 nucleotides but lack identifiable open reading frames (with rare exceptions). We highlight emerging evidence that lncRNAs are critical regulators of liver metabolic function and liver diseases. We summarize the current knowledge on the dysregulation of lncRNAs and outline the underlying molecular mechanisms by which lncRNAs control hepatic lipid and glucose metabolism and cholestatic liver disease. Liver-specific triglyceride regulator (lncLSTR), Lnc18q22.2, steroid RNA activator (SRA), highly upregulated in liver cancer (HULC), metastasis associated in lung adenocarcinoma transcript 1 (MALAT1), Liver glucokinase repressor (lncLGR), Maternally expressed gene 3 (MEG3), H19, lncHR1, lnc-HC, apolipoprotein A1 antisense transcript (APOA1-AS), DYNLRB2-2, and LXR-induced sequence (LeXis) are discussed.

The selective vulnerability of dopaminergic neurons in the substantia nigra pars compacta in Parkinson's disease, a late age onset neurodegenerative disorder, indicates the involvement of dopamine metabolism in the pathogenesis. Dopamine oxidation produces dopamine o-quinone, which covalently modifies cysteinyl proteins forming quinoprotein adduct. Although quinoprotein formation correlates with increased dopaminergic neurotoxicity, the in vivo protein targets for quinone modification remain unclear. Using two-dimensional gel electrophoresis and nitroblue tetrazolium/glycinate redox-cycling staining, we compared quinoprotein adducts in the substantia nigra of 2- and 15-month old rats and for the first time identified the in vivo protein targets with increased quinone modification in aged substantia nigra. Interestingly, several key enzymes in energy metabolism and mitochondrial function were selectively modified by quinone during aging. In vitro analyses confirmed that two of identified enzymes, l-lactate dehydrogenase (LDH) and malate dehydrogenase (MDH), were readily conjugated by dopamine o-quinone, resulting in a significant reduction in enzyme activity. Since the proteomic approach to detect quinoprotein adducts represents a single analysis comparing pools of substantia nigra from young or old rats, these findings need to be verified in the future. Nonetheless, our results reveal that the enzymatic activity of LDH and MDH can be compromised by quinone modification, suggesting a role of energy metabolism impairment in the selective vulnerability of aged substantia nigra dopaminergic neurons in Parkinson's disease.

In this paper, a novel stiffness coefficient model (SCM) is proposed for power flow distribution between two power sources, fuel cell system and battery. Then the energy management strategy is developed based on the SCM for a prototype FCHV. The power flow distribution in different power sources could be dynamically adjusted by the proposed strategy according to the logic relationship between the power demand and the fuel cell output power at peak efficiency point, and the fuel economy of the FCHV could be improved as much as possible by making the fuel cell system work in high-efficiency area. The designed control strategy is verified by the simulation and the practical test. In the test, for a combined cycle which includes three typical driving cycles, the fuel economy of the FCHV with the proposed control strategy is increased averagely by 5.18% with maintaining power balance and stable control.

Angiotensin converting enzyme (ACE, EC 3.4.15.1) is a membrane-bound, zinc dependent dipeptidase that catalyzes the conversion of the decapeptide angiotensin I to the potent vasopressor octapeptide angiotensin II by removing the two C-terminal amino acids. ACE is well known to be a key part of the rennin-angiotensin system that regulates blood pressure. The inhibitors of ACE have the potency of treating hypertension. This article reviews the structure-function relationship of ACE as well as its gene polymorphism and inhibitor development. In particular, it has been found that the catalytic mechanisms of the two active sites of somatic ACE in the cleavage of angiotensin I and bradykin are different. Therefore, by specifically targeting the individual active sites of somatic ACE, it will likely offer a new way to develop novel ACE inhibitors with fewer side effects.