Flexible nanomechanical bit based on few-layer graphene.

Mechanical computers have gained intense research interest at size scales ranging from nano to macro as they may complement electronic computers operating in extreme environments. While nanoscale mechanical computers may be easier to integrate with traditional electronic components, most current nanomechanical computers are based on volatile resonator systems that require continuous energy input. In this study, we propose a non-volatile nanomechanical bit based on the quasi-stable configurations of few-layer graphene with void defects, and demonstrate its multiple quasi-stable states by deriving an analytic relationship for the void configuration based on a competition between the bending energy and the cohesive energy. Using this nanomechanical bit, typical logic gates are constructed to perform Boolean calculations, including NOT, AND, OR, NAND and NOR gates, and demonstrate reprogrammability between these logic gates. We also study the accuracy and the stability of the nanomechanical bits based on the few-layer graphene. These findings provide a novel approach to realize the nanomechanical computing process.

Nonlinearity induced negative Poisson's ratio of two-dimensional nanomaterials.

Materials exhibiting a negative Poisson's ratio have garnered considerable attention due to the improved toughness, shear resistance, and vibration absorption properties commonly found in auxetic materials. In this work, the nonlinear effect on the Poisson's ratio was derived theoretically and verified by first-principle calculations and molecular dynamics simulations of two-dimensional nanomaterials including graphene and hexagonal boron nitride. The analytic formula explicitly shows that the Poisson's ratio depends on the applied strain and can be negative for large applied strains, owing to the nonlinear interaction. Both first-principle calculations and molecular dynamics simulations show that the nonlinear effect is highly anisotropic for graphene, where the nonlinearity-induced negative Poisson's ratio is much stronger for the strain applied along the armchair direction. These findings provide valuable insights into the behavior of materials with negative Poisson's ratios and emphasize the importance of considering nonlinear effects in the study of the Poisson's ratio of two-dimensional materials.

Additive interactions between obesity and insulin resistance on hypertension in a Chinese rural population.

BACKGROUND: Adiposity and insulin resistance (IR) are closely associated with hypertension; however, the role of interactions between obesity phenotypes and IR in hypertension is unclear. This study aimed to evaluate the interactions of body mass index (BMI), waist circumference (WC), and body fat percentage (BF%) with IR on hypertension risk. METHODS: We analyzed data from 4888 participants (mean age 57 years, 41.2% men) in the China Northwest Natural Population Cohort, Ningxia Project. BMI, WC, and BF% were determined using bioelectrical impedance analysis devices. IR was estimated using a homeostasis model assessment index (HOMA-IR). Multivariable-adjusted logistic regression was used to evaluate the association between HOMA-IR and hypertension risk. We calculated the relative excess risk and attributable proportion with their 95% confidence intervals (CIs) to assess whether adiposity phenotypes modified the effect of HOMA-IR on hypertension risk. RESULTS: The crude prevalence of hypertension was 52.2%. The multivariable-adjusted odds ratio of HOMA-IR was 1.80 (95% CI: 1.23-2.65) for the risk of hypertension in the highest versus the lowest quartiles, but this association became marginal in models further adjusting for BMI, WC, and BF% (P for trend = 0.056). Relative excess risk and attributable proportion for interaction between high HOMA-IR and high BF% were 0.32 (0.04-0.59) and 0.33 (0.06-0.60), respectively. Additionally, high truncal and leg BF% and high HOMA-IR accounted for the hypertension risk in women, but not in men. We did not observe any significant interactions between BMI or WC and HOMA-IR on hypertension. CONCLUSION: BF% modified the association between IR and increased risk of hypertension in women with high truncal and leg BF%, but not in men.

Dietary inflammatory index, dietary total antioxidant capacity, and frailty among older Chinese adults.

OBJECTIVES: Frailty is an age-related syndrome associated with poor health outcomes. Studies in developed countries indicate that the dietary inflammatory index (DII) and dietary total antioxidant capacity (DTAC) are important dietary factors influencing the risk of frailty in older adults. However, few studies have explored the association between DII, DTAC, and frailty among older Chinese adults. The objective of the current study was to examine whether DII and DTAC were associated with pre-frailty or frailty among older Chinese adults. DESIGN: A cross-sectional study. SETTING: Community-based. PARTICIPANTS: We included 6414 participants aged ≥60 years. MEASUREMENTS: Dietary intake was assessed using a validated food frequency questionnaire (FFQ). The DII and energy-adjusted DII (E-DII) were calculated using food parameters. DTAC was estimated using two widely adopted antioxidant scores: DTAC based on ferric reducing antioxidant power and dietary antioxidant quality score (DAQS) obtained from vitamins (vitamins A, C, and E) and minerals (zinc and selenium) with antioxidant functions. Frailty was assessed using the frailty index (FI) calculated from 28 health-related deficits. Individuals were classified as robust (FI ≤ 0.10), pre-frailty (FI > 0.10 to <0.25), or frailty (FI ≥ 0.25). Multiple logistic regression models were used to evaluate the associations of DII and DTAC with pre-frailty and frailty. RESULTS: After adjusting for confounding factors, individuals in the highest DII quintile (Q5) were more likely to have pre-frailty (odds ratio [OR] = 1.56; 95% confidence interval [CI]: 1.25-1.93; P for trend <0.001) than those in the lowest Q1. A similar positive association was detected for E-DII and pre-frailty. A significant association was found between DII and frailty. Compared with the lowest Q1, the highest Q5 of DTAC was negatively correlated with pre-frailty (OR = 0.66; 95% CI: 0.52-0.84; P for trend <0.001) and frailty (OR = 0.71; 95% CI: 0.50-0.1.03; P for trend <0.001). The DAQS yielded results similar to pre-frailty results (OR = 0.72; 95% CI: 0.58-0.89; P < 0.001). There was no evidence suggesting an association between DAQS and frailty. CONCLUSIONS: More proinflammatory diets were linked to higher pre-frailty risk, whereas higher levels of dietary antioxidants were associated with lower pre-frailty and frailty risk among older Chinese adults.

Association between dietary antioxidant capacity and type 2 diabetes mellitus in Chinese adults: a population-based cross-sectional study.

BACKGROUND: Higher intakes of dietary antioxidants have been linked to a lower type 2 diabetes mellitus (T2DM) risk. However, few studies have comprehensively examined the overall dietary antioxidant capacity, assessed by dietary antioxidant quality scores (DAQS) and dietary total antioxidant capacity (DTAC), related to T2DM risk, especially in populations consuming relatively monotonous diets. This study aimed to evaluate the associations of DAQS, DTAC, and T2DM among rural Chinese adults. METHODS: Data from 12,467 participants from the Natural Population Cohort of Northwest China: Ningxia Project was analyzed. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire. DAQS were calculated based on vitamins A, C, and E, zinc (Zn), and selenium (Se) intake. DTAC was estimated using the ferric-reducing ability of plasma assay. Logistic regression models were used to evaluate the associations of DAQS and DTAC with T2DM risk. Restricted cubic splines were used to assess potential non-linear relationships between DTAC and T2DM. RESULTS: T2DM was observed in 1,238 (9.9%) participants. After adjusting for confounders, compared to the lowest tertiles (T1) of DAQS, the odds ratios (ORs) for T2DM were 1.03 (95% CI 0.82-1.30) in T2 and 0.85 (95% CI 0.68-1.06) in T3 (P = 0.010). Compared to T1, the ORs for T2DM in the highest T3 were 0.78 (95% CI 0.67-0.91, P-trend = 0.008) for vitamin A, 1.34 (95% CI 1.15-1.56, P-trend < 0.001) for vitamin E, 0.83 (95% CI 0.71-0.97, P-trend = 0.007) for Se, and 0.86 (95% CI 0.74-1.01, P-trend = 0.033) for Zn. Compared to the lowest quartile(Q1) of DTAC, the OR in the highest Q4 was 0.96 (95% CI 0.80-1.17, P-trend = 0.024) for T2DM. A non-linear relationship was observed between DATC and T2DM. CONCLUSION: Higher DAQS and DATC were associated with a lower T2DM risk, suggesting that consuming antioxidant-rich foods may reduce the T2DM risk.

Associations between Low-Carbohydrate Diets and Low-Fat Diets with Frailty in Community-Dwelling Aging Chinese Adults.

Frailty is a major health issue associated with aging. Diet affects frailty status; however, studies on the associations between the low-carbohydrate diet (LCD) score, low-fat diet (LFD) score and frailty in older Chinese adults are scarce. This study aimed to examine the associations between the LCD score, LFD score and risk of frailty in older Chinese adults. We analyzed data from 6414 participants aged ≥ 60 years from the China Northwest Natural Population Cohort: Ningxia Project. Frailty was measured using the frailty index (FI), calculated from 28 items comprising diseases, behavioral disorders and blood biochemistry and classified as robust, pre-frail and frail. LCD and LFD scores were calculated using a validated food frequency questionnaire (FFQ). Multiple logistic regression models were used to evaluate associations between LCD, LFD scores and frail or pre-frail status after adjusting for confounders. Participants' mean age was 66.60 ± 4.15 years, and 47.8% were male. After adjusting for age, sex, educational level, drinking, smoking, BMI, physical activity and total energy, compared to the lowest quartile (Q1: reference), the odds ratios (ORs) for pre-frail and frail status in the highest quartile (Q4) of LCD score were 0.73 (95% confidence intervals: 0.61-0.88; p for trend = 0.017) and 0.73 (95%CI: 0.55-0.95; p for trend = 0.035), respectively. No significant associations were observed between LFD score and either pre-frail or frail status. Our data support that lower-carbohydrate diets were associated with lower pre-frail or frail status, particularly in females, while diets lower in fat were not significantly associated with the risk of either pre-frail or frail status in older Chinese adults. Further intervention studies are needed to confirm these results.

Association of Non-Insulin-Based Insulin Resistance Indices with Risk of Incident Prediabetes and Diabetes in a Chinese Rural Population: A 12-Year Prospective Study.

Objective: Three non-insulin-based insulin resistance (IR) indices, ie, triglyceride-glucose (TyG) index, triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio, and metabolic score for IR (METS-IR), were considered powerful and simplified alternatives for IR. However, evidence for the association between the three IR indices and incident type 2 diabetes mellitus (T2DM), especially impaired fasting glucose (IFG), remains limited. Therefore, this study aimed to explore the association among IR indices, incident IFG, and T2DM in a rural population cohort. Methods: We analyzed data from 2209 adults (aged 24-75 years) at baseline and from 1205 normoglycemic participants who were followed up. Cox proportional hazards models were used to evaluate the associations between the three indices and IFG or T2DM. Restricted cubic spline curves based on the Cox regression model were used to examine the association between baseline indices and incident T2DM. Results: For the baseline data, logistic analyses demonstrated that the TyG index, TG/HDL-C ratio, and METS-IR had a significantly positive correlation with IFG or T2DM after multivariable adjustment. During a median follow-up of 12.17 years, 157 incident cases of IFG and 97 incident cases of T2DM were noted. The risk of T2DM, but not IFG, was strongly associated with the baseline TyG index in the adjusted model, and participants with the TyG index in the third tertile had a higher risk of developing T2DM (adjusted hazards ratio, 2.84; 95% confidence intervals, 1.26-6.37; p for trend <0.001) than those in the lowest tertile (reference). Moreover, a linear relationship was observed between the TyG index and T2DM incidence. The TG/HDL-C ratio and METS-IR had no significant relationship with the risk of IFG or T2DM. Conclusion: The TyG index is more useful than the TG/HDL-C ratio and METS-IR in predicting T2DM in the normoglycemic population.

[Effect of electroacupuncture preconditioning on myocyte apoptosis in myocardial ischemia-reperfusion injury rats based on FXR/SHP pathway].

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on left-cardiac function, contents of serum TNF-α and IL-6 and expression of myocardial farnesoid X receptor(FXR), small heterodimer partner (SHP), apoptosis inducing factor (AIF) and heat shock proteins 70 (HSP70) genes in myocardial ischemia-reperfusion injury (MIRI) rats, so as to explore its mechanisms underlying improvement of ischemic myocardial injury. METHODS: Forty male Wistar rats were randomly divided into normal control, sham operation, MIRI model and EA pretreatment groups, with 10 rats in each group. Rats of the sham operation group received exposure of the thorax and heart. The MIRI model was established by occlusion of the anterior descending branch of the left coronary artery (LAD). EA (2 Hz/100 Hz and 1 mA) was applied to bilateral "Neiguan" (PC6), "Zusanli" (ST36) and "Guanyuan" (CV4) for 20 min, once a day for 7 days. The left ventricular end-diastolic pressure (LVEDP), left ventricular systolic pressure (LVSP)and maximal rates of rise and fall of left ventricular pressure (±dp/dtmax) were detected, the contents of serum TNF-α and IL-6 were detected by using enzyme-linked immunosorbent assay (ELISA), and the expression of FXR, SHP, AIF and HSP70 apoptotic genes in the myocardial tissue were measured by fluorescent quantitative RT-PCR. RESULTS: Compared with the normal control group, the LVEDP, contents of serum TNF-α and IL-6, and the expression levels of myocardial FXR, SHP, AIF and HSP70 mRNAs were significantly increased (P<0.05), while LVSP and ±dp/dtmax levels were obviously decreased in the model group (P<0.05). In comparison with the model group, MIRI-induced increases of LVEDP, TNF-α and IL-6 contents, and FXR, SHP and AIF mRNA expression and decreases of ±dp/dtmax and LVSP levels were reversed(P<0.05), except HSP70 mRNA expression with significantly increased (P<0.05) in the EA pretreatment group. CONCLUSION: EA pretreatment can protect the left ventricular function of the ischemic heart in MIRI rats, which may be related to its effects in reliving peripheral inflammation and regulating the expression levels of apoptosis-related factors FXR, SHP, AIF and HSP70 in the myocardium.

Acupuncture and related therapies for stable angina pectoris: A protocol for network meta-analysis.

BACKGROUND: Stable angina pectoris (SAP) is one of the important causes and harbingers of disability and mortality worldwide in the cardiovascular diseases. Acupuncture has been widely applied in the treatment and prevention of cardiovascular diseases in recent years. This systematic review protocol aims to analyze different acupuncture and related therapies to treat SAP, with a view to providing an evidence-based basis for clinical implementation of treatment for patients with SAP. METHODS AND ANALYSIS: The electronic databases of PubMed, EMBASE, The Cochrane Library, Chinese National Knowledge Infrastructure (CNKI), Wanfang database, Chinese Science and Technology Periodical Database (VIP), and China Biology Medicine Database (CBM) will be searched from inception to November 2020. The outcome measures were angina attack frequency, ECG changes, angina pain intensity, performance on the Six-Minute Walk Test (6-MWT) and reported adverse events. Study inclusion, data extraction and quality assessment will be performed independently by 2 reviewers. STATA 14.0 will be used to perform pairwise meta-analysis. STATA 13.0 and WinBUGS 1.4.3 will be used to perform pairwise meta-analysis and will be used to conduct network meta-analyses. RESULTS: The results of this review will generate a comprehensive review of current evidence and be published on a peer-reviewed journal. CONCLUSIONS: The result of this network meta-analysis is expected to provide a possible ranking for acupuncture treatment methods of stable angina pectoris and offer better options for patients with stable angina pectoris. ETHICS AND DISSEMINATION: Ethical approval is not necessary since this protocol is only for systematic review and does not involve privacy data or conduct an animal experiment. This protocol will be disseminated by a peer-review journal or conference presentation. TRIAL REGISTRATION NUMBER: INPLASY2020110035.

[Effect of electroacupuncture preconditioning on cell apoptosis mediated by mitochondrial reactive oxygen species in myocardial ischemia/reperfusion injury rats].

OBJECTIVE: To observe the effect of electroacupuncture (EA) preconditioning on cell apoptosis and the content of mitochondrial reactive oxygen species (ROS) in rats with myocardial ischemia/reperfusion injury (MIRI), so as to explore their mechanisms underlying improvement of MIRI. METHODS: Eighty male Wistar rats were randomly divided into control, sham, ischemia reperfusion (IR) and EA groups, with 20 rats in each group. Rats of the control, sham and IR groups were just banded on the boards for 30 min, once daily for 7 days. Before modeling, EA (2 Hz, 1 mA) was applied to "Neiguan" (PC6), "Zusanli" (ST36), "Guanyuan"(CV4) for 20 min, once daily for 7 successive days in the EA group. The MIRI model was established by occlusion of the left anterior descending branch of the left coronary artery for 20 min, followed by reperfusion for 30 min. Ventricular arrhythmia (VA) score was used to evaluate arrhythmia. Enzyme-linked immunosorbent assay (ELISA) was used to detect the level of CK-MB. DHE staining was used to detect the content of reactive oxygen species (ROS). The gene expression levels of cytochrome C (Cyt-C), Caspase-9 and Caspase-3 were detected by real-time fluorescent quantitative PCR. RESULTS: Compared with the sham group, VA score, serum CK-MB content, ROS content in heart tissue and Cyt-C, Caspase-9 and Caspase-3 gene expression were significantly up-regulated in the MIRI group (all P<0.01). Following the intervention, the increased VA score, serum CK-MB content, ROS content in heart tissue, Cyt-C, Caspase-9 and Caspase-3 gene expression were all reversed in the EA group compared with the MIRI group (all P<0.01). CONCLUSION: The protective effect of EA preconditioning on MIRI may be based on the regulation of ROS mediated-apoptosis pathway.

Genome-Wide Regulation of Electroacupuncture and Treadmill Exercise on Diet-Induced Obese Rats.

Acupuncture has been widely used for obesity treatment, but its mechanism is still unclear. To investigate the molecular mechanisms, we applied electroacupuncture (EA) at the Zusanli (ST36) acupoint and treadmill exercise (TE) in a diet-induced obese (DIO) rat model and used RNA sequencing (RNA-seq) to identify molecular consequences. Forty Sprague-Dawley male rats were selected and randomly divided into five groups: control (C), DIO model (M), EA, TE, and EA + TE groups. According to the results, acupuncture reduced body weight and the ratio of retroperitoneal white adipose tissue (retro-WAT) to body weight. Total RNA was extracted from the retro-WAT from five groups for RNA-seq. Differentially expressed genes (DEG) analysis showed that there were obvious differences among the four comparisons of C vs. M, M vs. EA, M vs. TE, and M vs. EA + TE, followed by 1383, 913, 3324, and 2794 DE genes. Gene ontology (GO) term enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were performed to further classify the DEGs. Several GO terms were commonly significantly enriched in both M vs. TE and M vs. EA, such as myofibril and muscle contraction. In addition, some pathways were regulated by EA and TE, such as the peroxisome proliferator activated receptor signaling pathway and calcium signaling pathway. This study is the first to compare and analyze the differences in gene expression profiles in the retro-WAT of rats in different groups, which provide a clue for further investigation into the molecular mechanisms of obesity treatment by EA and TE.

[Protective effect and regulating effect on FXR/SHP gene of electroacupuncture preconditioning on myocardial ischemia-reperfusion injury in rats].

OBJECTIVE: To explore the protective mechanism of electroacupuncture preconditioning on myocardial ischemia-reperfusion injury in rats. METHODS: A total of 88 SPF-grade Wistar male rats were randomized into a normal group, a sham-operation group, a model group and an electroacupuncture (EA) group, 22 rats in each one. The rats in the normal group received normal diet and no intervention was given for 7 d. The rats in the sham-operation and the model group were bound for 20 min, once a day for 7 d. In the EA group, EA, continuous wave, 2 Hz and 1 mA, was applied at "Neiguan" (PC 6), "Zusanli" (ST 36) and "Guanyuan" (CV 4) for 20 min, once a day for 7 d. In the 8th day, the blood was collected by abdominal aortic method 60 min after intraperitoneal injection of 10% urethane anesthesia by 10 mL/kg in the normal group, and then the tissue of heart was collected. In the model group and the EA group, ligating the left anterior descending coronary artery (LAD) was adopted for 20 min and reperfusion was applied for 40 min, then the samples were collected. The rats in the sham-operation group recevied open-chest operation and no other intervention, the samples were collected in 60 min. Nitro Blue Tetrazolium Chloride monohydrate (NBT) stain was used to detected myocardial infarct size and weight, ELISA was used to measured myocardial injury markers and inflammatory factors (LDH、CK、cTnI), and the fluorescent quantitative PCR method was used to determine the expressions of FXR and SHP gene. RESULTS: ①There was no significant difference between the normal group and the sham-operation group in myocardial infarct size and weight (P>0.05) .Compared with the normal group, myocardial infarct size and weight were higher in the model group (P<0.01). Compared with the model group, myocardial infarct size and weight were lower in the EA group (P<0.01). ②There was no significant difference between the normal group and the sham-operation group in serum contents of LDH、CK、cTnI (P>0.05). Compared with the normal group, the serum contents of LDH、CK、cTnI were higher in the model group (P<0.05). Compared with the model group, the serum contents of LDH、CK、cTnI were lower in the EA group (P<0.05). ③The expressions of FXR and SHP gene in the model group were higher than those in the normal group (P<0.05). The expressions of FXR and SHP gene in the EA group were lower than those in the model group (P<0.05). CONCLUSION: Electroacupuncture preconditioning could significantly improve cardiac function of rats with myocardial ischemia-reperfusion, reduce infarct size and inflammatory factors, and down-regulate the expressions of FXR and SHP gene. The protective effect may generate based on regulation of FXR/SHP apoptosis signal pathway.