The type-I, III nodal ring, type-I, III quadratic nodal point, and Dirac valley phonons in 2D kagome lattices M2C3(M = As, Bi, Cd, Hg, P, Sb, Zn).

Topological phases in kagome systems have garnered considerable interest since the introduction of the colloidal kagome lattice. Our study employs first-principle calculations and symmetry analysis to predict the existence of ideal type-I, III nodal rings (NRs), type-I, III quadratic nodal points (QNPs), and Dirac valley phonons (DVPs) in a collection of two-dimensional (2D) kagome lattices M2C3(M = As, Bi, Cd, Hg, P, Sb, Zn). Specifically, the Dirac valley points (DVPs) can be observed at two inequivalent valleys with Berry phases of +πand-π, connected by edge arcs along the zigzag and armchair directions. Additionally, the QNP is pinned at the Γ point, and two edge states emerge from its projections. Notably, these kagome lattices also exhibit ideal type-I and III nodal rings protected by time inversion and spatial inversion symmetries. Our work examines the various categories of nodal points and nodal ring phonons within the 2D kagome systems and presents a selection of ideal candidates for investigating topological phonons in bosonic systems.

Tracking the Immediate and Short-Term Effects of Continuous Theta Burst Stimulation on Dynamic Brain States.

Continuous Theta Burst Stimulation (cTBS) has been shown to modulate cortical oscillations and induce cortical inhibitory effects. Electroencephalography (EEG) studies have shown some immediate effects of cTBS on brain activity. To investigate both immediate effects and short-term effects of cTBS on dynamic brain changes, cTBS was applied to 22 healthy participants over their left motor cortex. We recorded eyes-open, resting-state EEG and performance in the Nine-Hole Peg Test (NHPT) before cTBS, immediately after cTBS, and 80 minutes after cTBS. We identified nine states using a Hidden Markov Model (HMM)-based approach to describe the process of dynamic brain changes. The spatial activation, temporal profiles of HMM states and behavioral performance of NHPT were assessed and compared. cTBS altered the temporal profiles of S1-S5 immediately after cTBS and the temporal profiles of S5, S6 and S7 80 min after cTBS. Moreover, cTBS improved motor function of the left hand. State 1 was characterized as the activation of right occipito-temporal area, and NHPT behavioral performance of the left hand positively correlated with the occurrence of state 1, and negatively correlated with the interval time of state 1 after cTBS. The transitions between S1 or S7 and other states showed dynamic reconfiguration during after-effect sustained time after cTBS. These results suggest that the dynamic characteristics of state 1 are potential biomarkers for characterizing the aftereffect changes of cTBS.

Hydrogeochemical Disparities and Constraints of Water Produced from Various Coal Seams in the Baode Block, Ordos Basin, China.

The hydrogeochemical characteristics of coalbed water play a crucial role in assessing the production level of coalbed methane (CBM) due to its involvement in the entire process of CBM generation, migration, accumulation, and extraction. To investigate variations in hydrochemical characteristics and controlling factors among different coal seams, a representative CBM field (Baode block) within the Ordos basin in China was chosen as a target. We have systematically collected produced water samples from coal seams of the Permian Shanxi Formation (P1s) and Taiyuan Formation (P1t). Tests and analyses were conducted on conventional cation and anions, trace elements, pH value, total dissolved solids (TDS), stable isotopes of hydrogen and oxygen in water, and inorganic carbon (δD, δ18O, and δ13CDIC). The findings indicate that the P1s coal seam primarily contains HCO3-Na type water, while the P1t coal seam consists of Cl-Na and HCO3-Na types of water. The disparity in water types between P1s and P1t can be attributed to interactions between water and rocks. The isotopic compositions of δD, δ18O, and δ13CDIC suggest that the sampled coalbed waters originate from atmospheric precipitation, with subsequent microbial activity. It is suggested that TDS content along with bicarbonate concentration can serve as effective indicators for determining high productivity due to weaker hydraulic conditions and a more enclosed water environment in P1t coal seams; threshold values being >1000 mg/L for TDS and >10 mequiv/L for bicarbonate concentration. Additionally, microbial activity is found to be more widespread in P1t compared to P1s. Principal component analysis reveals a significantly higher contribution of conventional ions toward TDS content observed within the P1t coal seam compared to that of P1s coal seam, accompanied by alterations in pH control parameters. The water produced from the P1s coalbed is primarily controlled by evaporite and silicate weathering/dissolution coupled with substantial cation exchange. Conversely, the water in the P1t coalbed is mainly influenced by silicate weathering/dissolution as well as evaporative concentration, with a limited occurrence of cation exchange. Moreover, there are distinct disparities in ion sources between P1s and P1t. These research findings provide a scientific foundation for assessing the development potential of CBM and optimizing extraction systems within similar CBM areas.

Experimental Studies on the Explosion Behaviors of Premixed Hydrogen-Air Mixtures in a Narrow Channel.

Premixed hydrogen-air explosion experiments were carried out in a 1000 mm × 50 mm × 10 mm half-open narrow channel, concerning with the influences of equivalence ratio and ignition position on explosion behaviors. Experimental phenomena were different from explosion in large space. The results indicated that when ignited at the closed end of the channel, three overpressure peaks appeared, caused by the rupture of the film, Helmholtz Oscillation, and the flame-acoustic interaction, respectively. As the equivalence ratio of the hydrogen-air mixtures varied from 0.6 to 1.6, the peak overpressure first increased and then decreased. The maximum peak overpressure occurred at ϕ = 1.2. The hydrogen flame would develop into the plane tulip structure without the influence of the end wall. With the ignition position moved to the open end, overpressure wave and flame oscillated significantly. Compared with other ignition positions, the minimum value of P max was obtained at IP950. Based on the explosion behaviors in the narrow channel, it was concluded that the closer the ignition was to the open end, the easier the oscillation was to be formed, the smaller the explosion hazard was.

Flame Propagation Characteristics of Syngas-Air in the Hele-Shaw Duct with Different Equivalence Ratios and Ignition Positions.

In this paper, the effects of different ignition positions and equivalence ratios on the explosion characteristics of syngas in a half-open Hele-Shaw duct were investigated. The ignition points are set at distances of 0 and 500 mm from the closed end. Moreover, the research range of equivalence ratio is 0.8-1.2. The experimental results indicate that different ignition positions and equivalence ratios influence the flame front structure and the dynamic characteristics of flame propagation. When the ignition position is at the closed end, the flame front undergoes several typical propagation stages before eventually reaching the open end of the duct. The time required by the flame to reach the open end decreases as the equivalence ratio increases. Meanwhile, when the ignition is in the middle of the duct, the flame simultaneously spreads to the open and closed ends. The time required to reach both sides decreases with the increase in the equivalence ratio. The flame front structure and pressure are primarily affected by the ignition position and the equivalence ratio. At the same ignition position, flame propagation velocity and maximum overpressure increase with the equivalence ratio. The pressure oscillation becomes more intense when the ignition position is close to the open end. At IP500, when the equivalence ratio is 0.8, multiple finger-shaped flame fronts emerge, accompanied by high-frequency flame oscillations. This study can provide guidance for the study of the flame propagation characteristics of syngas in millimeter-scale burners.

Pulmonary disease and periodontal health: a meta-analysis.

OBJECTIVE: Research has shown a positive relationship between pulmonary and periodontal disease. However, the relationship remains unclear. The aim of this meta-analysis was to evaluate the associations between pulmonary disease and periodontal health. MATERIALS AND METHODS: MEDLINE, PubMed, EMBASE, Web of Science, Science Citation Index, Wanfang, and CNKI were searched for all the relevant studies of relationship between pulmonary disease and periodontal health. Weighted mean difference (WMD)/odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of the association. RESULTS: Thirty-seven studies were included in this meta-analysis. Pooled analysis showed a significant association between pulmonary and periodontal disease (adjusted OR, 1.93; 95%CI: 1.60-2.33; P < 0.05), and pooled adjusted OR was 1.64, 3.03, and 2.21 in COPD, asthma, and pneumonia, respectively. The pooled analysis also showed that patients with pulmonary disease suffered from worse periodontal health as most periodontal indexes in those patients were poorer. CONCLUSIONS: There is a strong association between pulmonary disease and periodontal health. Clinical trials analyzing the causality and pathological basis of the association of these two diseases are needed.

Serum netrin-1 as a potential biomarker for functional outcome of traumatic brain injury.

BACKGROUND: Decreased serum netrin-1 concentrations have been found after acute brain injury. We investigated the role of serum netrin in prognosis of traumatic brain injury (TBI). METHODS: In this prospective and observational study, enzyme-linked immunosorbent assay was used to detect serum netrin-1 concentrations in 50 mild TBI patients (Glasgow coma scale (GCS) score, 13-15), 83 moderate TBI patients (GCS score, 9-12), 69 severe TBI patients (GCS score, 3-8) and 50 healthy controls. Glasgow outcome scale score of 1-3 at 6 months after trauma was defined as poor outcome. RESULTS: Serum netrin-1 concentrations were significantly lower in moderate or severe TBI patients than in controls and in severe TBI patients than in moderate TBI patients, while not in mild TBI patients than in controls. GCS score and Rotterdam computed tomography classification were closely correlated with serum netrin-1 concentrations among TBI patients. Forty-two (20.8%) patients had poor outcome. Receiver operating characteristic curve analysis revealed that serum netrin-1 concentrations could distinguish patients with poor outcome from the other remainders significantly. In addition, serum netrin-1 concentrations were independently associated with poor outcome. CONCLUSIONS: Serum netrin-1 might serve as a potential biomarker for prognosis of TBI.

Thermodynamic Stabilities, Electronic Properties, and Optical Transitions of Intrinsic Defects and Lanthanide Ions (Ce3+, Eu2+, and Eu3+) in Li2SrSiO4.

Geometric structures, electronic properties, thermodynamic stabilities, and optical transitions of intrinsic defects (vacancies and antisite defects) and lanthanide ions (Ce3+, Eu2+, and Eu3+) in Li2SrSiO4 (LSSO) host are studied by theoretical calculations combined with hybrid density functional theory, the multireference configuration interaction method, and empirical models. Calculations on the defect formation energies and the ab initio simulations of 4f → 5d electronic transitions for Ce3+ ions determine the most possible charge-compensation mechanism and accurately identify excitation bands in experimental spectra for LSSO:Ce3+ phosphors. On the basis of previously reported experimental spectra of Ce3+- and Eu3+-doped LSSO phosphors as well as a series of empirical models developed by Dorenbos, the locations of the 4f ground states and the lowest 5d excited states of Ln3+ and Ln2+ ions in the host (illustrated by the host-referred binding energy scheme, i.e., the HRBE scheme) are obtained, which is useful for the investigation of the electron-transfer and spectroscopic properties in lanthanide-doped LSSO. Moreover, thermodynamic and optical transition energy levels related to intrinsic defects and lanthanide ions (with various charge states) are derived from total energy calculations. The mechanisms of thermoluminescence (TL) and long-lasting luminescence (LLL) in LSSO:Eu2+,Dy3+ phosphors and especially the contributions of oxygen vacancies ( VO) and Dy3+ dopants are then interpreted. The aim of this study is thus to deeply understand the mechanisms of charge compensation, TL, and LLL in lanthanide-doped phosphors from theoretical calculations and analyses.

A meta-analysis of obstructive sleep apnea in patients with cerebrovascular disease.

BACKGROUND: There is increasing evidence that there is a direct relationship between obstructive sleep apnea (OSA) and cerebrovascular (CV) disease. This meta-analysis includes prospective cohorts and cross-sectional studies. It determines the prevalence of OSA among patients with CV disease and also looks for the risk o f cerebrovascular events among patients with OSA. METHOD: We conducted a computerized literature search in the databases of Medline, Embase, Wanfang, CNKI, Wiley Online Library, and CINAHL (date till April 2017). The random effects model was used to pool the hazard ratio (HR) and effect sizes (ES). Heterogeneity, subgroup, sensitivity analyses, and publication bias were performed. RESULT: Fifty-eight studies involving 3 million patients/participants were included. The pooled HR of 15 prospective cohort studies indicated a significant association between OSA and the risk of CV disease after adjustment confounding factors (HR 1.94; 95% CI 1.31-2.89; P = 0.001), and OSA is present in up to 58.8% of patients with CV disease after pooling the remaining 43 studies. CONCLUSIONS: OSA is very common in patients with CV disease. Similarly, patients with OSA are prone to have CV disease.

Nuclear factor-κB as a link between endoplasmic reticulum stress and inflammation during cardiomyocyte hypoxia/reoxygenation.

Endoplasmic reticulum stress (ERS) can initiate inflammation, and the coupling of these responses is thought to be fundamental to the pathogenesis of cardiovascular disease. However, the mechanism linking ERS and inflammation in myocardial ischemia/reperfusion needs further investigation. Cultured cardiomyocytes were pretreated with SP600125 or salubrinal, followed by tunicamycin to clarify the involvement of the IRE1α and PERK pathways in ERS inflammation. The cardiomyocytes were given hypoxia/reoxygenation (H/R), and the effects of the NF-κB inhibitor, SN50, were followed. GRP78 protein levels were similar in the tunicamycin (Tm), salubrinal, and SP600125 groups, but were lower in cells treated with SN50. SN50 might effectively block the H/R-induced link between ERS and inflammation in cardiomyocytes by decreasing GRP78. This knowledge will aid in the development of therapies for myocardial ischemia/reperfusion injury.

Improvements in the primary culture of neonate rat myocardial cells by study of the mechanism of endoplasmic reticulum stress.

We previously found that endoplasmic reticulum stress (ERS) might be exhibited in the conventional protocol of the primary culture of neonate rat myocardial cells (NRMCs) and that the high glucose concentration (25 mmol/L) in the culture medium might be the cause. Here, we investigated if the high concentration of glucose might influence ERS in myocardial cells during culture. GRP78 expression (ERS marker) was similar in groups with tunicamycin (TM) and without TM in high glucose cultured cells (p > 0.01). Different glucose concentrations elicited different GRP78 expressions according to analyses of protein and RNA levels, which showed ERS in H/H groups. Finally, we found that GRP78 expression was higher in TM groups compared with M/M groups (p < 0.01). The conventional high-glucose culture media during primary culture of NRMCs induced ERS. We propose that medium-glucose culture media should be used and describe an improved protocol for the primary culture of NRMCs.

Inhibition of TNF-α by cyclophosphamide reduces myocardial injury after ischemia-reperfusion.

PURPOSE: The purpose of this study was to determine whether cyclophosphamide (CP) can decrease myocardial and systemic TNF-α expression and thus protects myocardial I/R injury. METHODS: Open chest rats were subjected to 30 min of ischemia followed by 3h, 12h or 24h of reperfusion. Rats were divided into sham group, I/R group and CP group, and each group included 3 timepoint subgroups (3h, 12h and 24h). Plasma TNF-α was measured by cytometric bead array (CBA) and immunohistochemistry was used to detect TNF-α in myocardium. RESULTS: Compared with I/R group, rats treated with CP showed a significant difference with decreased plasma TNF-α (13.31 ± 2.62 vs 14.13 ± 5.95 pg/mL at 3 h reperfusion, 10.1 ± 2.73 vs 12.54 ± 5.00 pg/mL at 12 h reperfusion, 10.38 ± 5.59 vs 13.00 ± 3.59 pg/mL at 24 h reperfusion, p <0.05 respectively). Immunostaining was less intense with CP injection at each reperfusion time. The score of the intensity of myocardial TNF-α staining was down regulated. CONCLUSIONS: TNF-α is expressed in the myocardium and plasma after myocardial I/R injury. CP might be a feasible strategy for anti-TNF-α to protect myocardial I/R injury.

Investigation of cystatin C and cystatin C based estimated glomerular filtration rate in pregnant patients with heart failure.

BACKGROUND: Impaired cardiac function leads to impaired renal function. We assessed renal function in pregnant patients with heart failure. METHODS: This was a retrospective study. From 1999 to 2010, 42 pregnant patients with heart failure were classified into the single-pregnancy group and the twin or multifetation group. Clinical manifestations were assessed. Serum concentrations of creatinine and cystatin C were assessed. Estimated glomerular filtration rate (eGFR) based on serum concentrations of creatinine or cystatin C was completed. RESULTS: There were 29 single pregnancies, 12 twin pregnancies, and one multifetation. Ten patients in the twin pregnancy or multifetation group had in-vitro fertilization. The concentration of creatinine was 84.6±33.8 µmol/L and the creatinine-based eGFR was 87.2±34.9 mL/min per 1.73 m2. The percentage of patients with a creatinine based eGFR<60 mL/min per 1.73 m2was 23.8%. The concentration of cystatin C was 1.5±0.7 mg/L and the cystatin C-based eGFR was 65.2±45.8 mL/min per 1.73 m2. The percentage of patients with a cystatin C-based eGFR<60 mL/min per 1.73 m2was 52.4%. CONCLUSIONS: Serum concentrations of cystatin C and cystatin C-based eGFR are important indicators of renal impairment in pregnant patients with heart failure.

Cardiac injury in patients with pandemic 2009 influenza A (H1N1) infection.

BACKGROUND: In March 2009, the novel 2009 influenza A (H1N1) was first reported in the southwest of Mexico, and rapidly spread worldwide. We investigated the clinical features of cardiovascular involvement of patients infected with the 2009 influenza A (H1N1) virus in China. METHODS: This retrospective study recruited one hundred and seventy-two patients with 2009 influenza A (H1N1) of different severity (non-severe, severe, critically severe) and 21 patients who were influenza A (H1N1)-negative but who had an influenza-like illness. Blood was obtained for measurement of the concentration of creatine kinase (CK), creatine kinase-MB (CK-MB) and high sensitivity C-reactive protein (hs-CRP) in plasma. Chest radiography was also undertaken to calculate the cardiothoracic ratio (CTR). RESULTS: influenza A (H1N1) caused more illness in middle-aged people. The patients in the non-severe group were younger than in the severe group (P < 0.05) and the non-influenza A (H1N1) group (P < 0.01). The level of CK, CK-MB, hs-CRP and the CTR was higher in the critically severe group than in the other three groups (P < 0.001, P < 0.05, P < 0.01, P < 0.01, respectively). CONCLUSIONS: Myocardial injury was quite serious in severe infection by the influenza A (H1N1) virus, particularly in critically severe patients. Patients with 2009 influenza A (H1N1) had injury and dilation of the heart, which may be a potential cause of death.

The influence of influenza A (H1N1) virus on creatinine and cystatin C.

BACKGROUND: In March 2009, the novel 2009 influenza A (H1N1) virus was first reported in the southwestern USA and Mexico. It rapidly spread to China and worldwide. We investigated possible kidney injury in patients with the 2009 influenza A (H1N1) virus in China. METHODS: This study was a retrospective cohort investigation of the potential renal injury in patients of influenza. One hundred and seventy-two patients confirmed to have the 2009 influenza A (H1N1) virus but who had different levels of severity (non-severe, severe, and critically severe) and 21 cases who were influenza A (H1N1)-negative but who had an influenza-like illness were investigated. Blood samples were obtained for the measurement of creatinine (Cr) and cystatin C (Cy-C). RESULTS: The influenza A (H1N1) virus caused more illness in middle-aged people in all groups. The patients in the non-severe group were younger than those in the severe group (p<0.05) and the non-influenza A (H1N1) group (p<0.01). Four subjects in the critically severe group died (3 due to respiratory failure, 1 heart injury). A significant difference in the levels of Cr and Cy-C between the groups was not observed (p>0.05). CONCLUSION: The 2009 influenza A (H1N1) virus did not cause severe kidney injury in the acute phase in adult patients.