Super-Lubricious, Fullerene-like, Hydrogenated Carbon Films

Almost one-third of minimal energy is consumed via friction and wear process. Thus, to save energy using advanced lubrication materials is one of the main routes that tribologists are focused on. Recently, superlubricity is the most prominent way to face energy problems. Designing promising mechanical systems with ultra-low friction performance and establishing superlubricity regime is imperative not only to the most greatly save energy but also to reduce hazardous waste emissions into our environment. At the macroscale, hydrogenated diamond-like carbon (DLC) film with a supersmooth and fully hydrogen terminated surface is the most promising materials to realize superlubricity. However, the exact superlubricity of DLC film can only be observed under high vacuum or specific conditions and is not realized under ambient conditions for engineering applications. The latest breakthrough in macroscale superlubricity is made by introducing fullerene-like nano-structure and designing graphene nanoscroll formation, which also demonstrates the structure-superlubricity (coefficient of friction ~0.002) relationship. Thus, it is very interesting to design macroscale superlubricity by prompting the in situ formation of these structures at the friction interfaces. In this chapter, we will focus on fullerene-like hydrogenated carbon (FL-C:H) films and cover the growth methods, nanostructures, mechanic, friction properties and superlubricity mechanism

Thermoluminescence (TL) analysis for otoliths of the wild carps (cyprinoid) from Baiyangdian Lake and Miyun Reservoir: Some implications for monitoring water environment

Otolith is a typical biomineral carrier growing on insides of fish skull with prominent zoning structure formed by alternating layers of protein and calcium carbonate growing around the nucleus. Even though thermoluminescence (TL) analysis on biomineral has been widely used to measure the radiation exposure in the recent twenty years, the TL characteristics of the fish otolith have not yet been reported in literature. TL characteristics of otoliths from the wild carps (cyprinoid) living in the Baiyangdian Lake, Hebei Province and Miyun Reservoir, Beijing City was first studied, and the differences of energy gap (E) between the fish otoliths in the two waters have also been discussed in this paper. The experimental results indicated that TL curve parameters: peak temperature (Tp), luminous intensity (I), integrated intensity (S) and middle width (Wm) for the glow curves of the cyprinoid otoliths from Baiyangdian Lake are greater than those from Miyun reservoir, and the stability of the formers’ TL curve parameters value and energy gap (E) was weaker than the latter. In comparison to the Miyun Reservoir, the analysis manifested that the electrons and vacancies trapped in the otoliths from Baiyangdian Lake are more likely to escape. According to the investigation, the contaminative degree and eutrophication in the water of Baiyangdian Lake was heavier than that of Miyun Reservoir. Therefore, the characteristics of TL growth curves of the cyprinoid otoliths is quite sensitive to heavier contaminated and less contaminated water, and this could be regarded as an important typomorphic biomineral for monitoring the contaminative degree and environment change of the water.Keywords: Cyprinoid otoliths, thermoluminescence, water environment, typomorphic minera

Analysis of Flavor Quality of Two Cherry Tomatoes After Refrigeration

To investigate the differences in the types and relative contents of refrigerated volatile flavor substances between 'Chitose' and 'Ji Tian No.1' cherry tomatoes, the effect of cold storage at 4 ℃ for 16 d on the flavor quality of cherry tomatoes ('Chitose' and 'Ji Tian No.1') was analyzed by using electronic nose and headspace solid-phase microextraction-gas chromatography. The results showed that electronic nose analysis results displayed, the volatile substances that undergo significant changes before and after refrigeration in two cherry tomatoes were inorganic sulfides, nitrogen oxides, and aromatic substances, a total of 93 volatile substances were detected by HS-SPME-GC-MS technique, including 27 aldehydes, 23 alcohols, 4 esters, 11 ketones, 3 furans, 9 alkanes, 12 olefins and 4 other substances. Compared to 0 d, the relative content of total volatile substances in 'Chitose' and 'Ji Tian No.1' after cold storage decreased by 7.08% and 3.68% respectively. The relative content of the main volatile compounds hexanal and trans-2-hexenal in two cherry tomatoes decreased after refrigeration, the relative content of trans 2-pentenal, heptanal, 1-pentanol, 6-methyl-5-hepten-2-one, and 1-penten-3-one increased after refrigeration. Compared with 'Chitose', 'Ji Tian No.1' could retain higher contents of main volatile substances of cherry tomato such as aldehydes, esters and ketones after cold storage. Therefore, 'Ji Tian No.1' was more suitable for post-harvest storage and transportation and low-temperature refrigeration, which would provide a theoretical basis for high-quality cherry tomato post-harvest storage and transportation technology

Fuel consumption and exhaust emissions of diesel vehicles in worldwide harmonized light vehicles test cycles and their sensitivities to eco-driving factors

Large amounts of fossil fuels are 14 consumed by motor vehicles annually, and hazardous exhaust emissions from the motor vehicles have caused serious problems to environment and human health. Eco-driving can effectively improve the fuel economy and decrease the exhaust emissions, which makes it vital to analyze the fuel consumption and exhaust emissions at given driving cycle, and investigate their sensitivities to eco-driving factors. In this paper, the fuel consumption and exhaust emissions of a Euro-6 compliant light-duty diesel vehicle were tested in Worldwide Harmonized Light Vehicles Test Cycles on a chassis dynamometer; further, the sensitivities of the eco-driving factors that influence the fuel economy and exhaust emissions were analyzed using validated vehicle model. For the vehicle model simulation, the effect of the coolant temperature on fuel consumption and exhaust emission only considered its effect on lubricating oil viscosity. The results showed that vehicle acceleration and velocity dominates the fuel consumption rates in Worldwide Harmonized Light Vehicles Test Cycles, where more than 50% of the exhaust emissions was emitted in the first 300 seconds; also, fuel economy and exhaust emission factors showed a significant dependency on the road grade, coolant temperature, vehicle velocity and mass. For the driver-controllable factors, high vehicle velocity and low road grade (via route-choice) were recommended to achieve low fuel consumption and exhaust emissions

Association of long-term triglyceride-glucose index level and change with the risk of cardiometabolic diseases

ObjectiveThe triglyceride-glucose (TyG) index is considered as a pivotal factor for various metabolic, cardiovascular, and cerebrovascular diseases. However, there is currently a paucity of relevant studies on the association between long-term level and change of TyG-index and cardiometabolic diseases (CMDs) risk. We aimed to explore the risk of CMDs in relation to the long-term level and change of TyG-index.MethodsBased on the prospective cohort study, a total of 36359 subjects who were free of CMDs, had complete data of triglyceride (TG) and fasting blood glucose (FBG) and underwent four health check-ups from 2006 to 2012 consecutively were followed up for CMDs until 2021. The associations between long-term level and change of TyG-index and CMDs risk were assessed by Cox proportional hazards regression models to compute hazard ratios (HRs) and 95% confidence intervals (CIs). The TyG-index was calculated as ln [TG, mg/dL) × FBG, mg/dL)/2].ResultsDuring the median observation period of 8 years, 4685 subjects were newly diagnosed with CMDs. In multivariable-adjusted models, a graded positive association was observed between CMDs and long-term TyG-index. Compared with the Q1 group, subjects with the Q2-Q4 group had increased progressively risk of CMDs, with corresponding HRs of 1.64(1.47-1.83), 2.36(2.13-2.62), 3.15(2.84-3.49), respectively. The association was marginally attenuated, after further adjustment for the baseline TyG level. In addition, compared with stable TyG level, both loss and gain in TyG level were associated with increased CMDs risk.ConclusionsLong-term elevated level and change of TyG-index are risk factors for the incident CMDs. Elevated TyG-index in the early stage remains to exert cumulative effects on the occurrence of CMDs even after accounting for the baseline TyG-index

Proteomics Study of Peripheral Blood Mononuclear Cells (PBMCs) in Autistic Children

Autism is one of the most common neurological developmental disorder associated with social isolation and restricted interests in children. The etiology of this disorder is still unknown. There is neither any confirmed laboratory test nor any effective therapeutic strategy to diagnose or cure it. To search for biomarkers for early detection and exploration of the disease mechanisms, here, we investigated the protein expression signatures of peripheral blood mononuclear cells (PBMCs) in autistic children compared with healthy controls by using isobaric tags for relative and absolute quantitation (iTRAQ) proteomics approach. The results showed a total of 41 proteins as differentially expressed in autistic group as compared to control. These proteins are found associated with metabolic pathways, endoplasmic reticulum (ER) stress and protein folding, endocytosis, immune and inflammatory response, plasma lipoprotein particle organization, and cell adhesion. Among these, 17 proteins (13 up-regulated and four down-regulated) are found to be linked with mitochondria. Eight proteins including three already reported proteins in our previous studies were selected to be verified. Five already reported autism associated pro-inflammatory cytokines [interferon-γ (IFN-γ), interleukin-1β (IL-1β), IL-6, IL-12, and tumor necrosis factor-α (TNF-α)] were detected in plasma by enzyme-linked immunosorbent assay (ELISA) analysis. The results were consistent with proteomic results and reports from previous literature. These results proposed that PBMCs from autistic children might be activated, and ER stress, unfolded protein response (UPR), acute-phase response (APR), inflammatory response, and endocytosis may be involved in autism occurrence. These reported proteins may serve as potential biomarkers for early diagnosis of autism. More specifically, simultaneous detection of three proteins [complement C3 (C3), calreticulin (CALR), and SERPINA1] in the plasma and PBMCs could increase the authenticity of detection

Investigation of the Acetylation Mechanism by GCN5 Histone Acetyltransferase

The histone acetylation of post-translational modification can be highly dynamic and play a crucial role in regulating cellular proliferation, survival, differentiation and motility. Of the enzymes that mediate post-translation modifications, the GCN5 of the histone acetyltransferase (HAT) proteins family that add acetyl groups to target lysine residues within histones, has been most extensively studied. According to the mechanism studies of GCN5 related proteins, two key processes, deprotonation and acetylation, must be involved. However, as a fundamental issue, the structure of hGCN5/AcCoA/pH3 remains elusive. Although biological experiments have proved that GCN5 mediates the acetylation process through the sequential mechanism pathway, a dynamic view of the catalytic process and the molecular basis for hGCN5/AcCoA/pH3 are still not available and none of theoretical studies has been reported to other related enzymes in HAT family. To explore the molecular basis for the catalytic mechanism, computational approaches including molecular modeling, molecular dynamic (MD) simulation and quantum mechanics/molecular mechanics (QM/MM) simulation were carried out. The initial hGCN5/AcCoA/pH3 complex structure was modeled and a reasonable snapshot was extracted from the trajectory of a 20 ns MD simulation, with considering post-MD analysis and reported experimental results. Those residues playing crucial roles in binding affinity and acetylation reaction were comprehensively investigated. It demonstrated Glu80 acted as the general base for deprotonation of Lys171 from H3. Furthermore, the two-dimensional QM/MM potential energy surface was employed to study the sequential pathway acetylation mechanism. Energy barriers of addition-elimination reaction in acetylation obtained from QM/MM calculation indicated the point of the intermediate ternary complex. Our study may provide insights into the detailed mechanism for acetylation reaction of GCN5, and has important implications for the discovery of regulators against GCN5 enzymes and related HAT family enzymes