Non-Dipper Pattern is a Determinant of the Inappropriateness of Left Ventricular Mass in Essential Hypertensive Patients

Background and Objectives: Inappropriately high left ventricular mass (iLVM) is known to be related to cardiovascular prognosis. A non-dipper pattern has a greater mean left ventricular (LV) mass than the dipper pattern in hypertensive patients. However, the appropriateness of LV mass in dipper or non-dipper patterns has not been adequately investigated. The aim of this study was to define the relationship between nocturnal dipping and the appropriateness of LV mass. Subjects and Methods: Using the ambulatory blood pressure monitoring (ABPM) database, the data of 361 patients who underwent ABPM and echocardiography was analyzed retrospectively. Appropriateness of LV mass was calculated as observed/predicted ratio of LV mass (OPR) using a Korean-specified equation. Nocturnal dipping was expressed as percent fall in systolic blood pressure (BP) during the night compared to the day. Results: Daytime, nighttime and 24 hours BP in hypertensive patients was 140.4 +/- 14.8 mmHg, 143.7 +/- 15.2 mmHg and 129.4 +/- 20.0 mmHg, respectively. OPR was 106.3 +/- 19.9% and nocturnal dipping was 10.2 +/- 10.9 mmHg. In a multiple linear regression model, 24 hours systolic BP (beta=0.097, p=0.043) and nocturnal dipping (beta=-0.098, p=0.046) were independent determinants of OPR as well as age (beta=0.130, p=0.025) and body mass inde

The Relationship Between Ambulatory Arterial Stiffness Index and Blood Pressure Variability in Hypertensive Patients

Background and Objectives: Ambulatory arterial stiffness index (AASI) is well known as a predictor of cardiovascular mortality in hypertensive patients. Mathematically, AASI reflect the standard deviation (SD) of blood pressure (BP) variation. AASI is measured higher levels in non-dipper than dipper. Thus, AASI has a possibility of not only reflecting arterial stiffness but also BP variability and/or autonomic nervous dysfunction. Subjects and Methods: Consecutive data from 418 untreated hypertensive patients were analyzed retrospectively. We examined the association between the 24-hour ambulatory BP monitoring (ABPM) parameters and AASI. Results: AASI had a simple correlation with age (R=0.189, p<0.001), relative wall thickness (RWT) (R=0.115, p=0.019), left ventricular mass index (LVMI) (R=0.192, p<0.001), average systolic BP (SBP) (R=0.232, p<0.001), average pulse pressure (PP) (R=0.363, p<0.001), SD of diastolic BP (DBP) (R=-0.352,p<0.001), SD of PP (R=0.330, p<0.001), SD of heart rate (HR) (R=-0.268, p<0.001), and nocturnal dipping (R=-0.137, p=0.005). In multiple linear regression analysis model including clinical parameters and 24 hour-ABPM parameters, independent predictors of AASI were SD of PP (beta=1.246, p<0.001), SD of DBP (beta=-1.067, p<0.001), SD of SBP (beta=-0.197, p<0.001), and non-dipper (beta=0.054, p=0.033). Conclusion: AASI is closely correlated with BP variability. The result of this study shows that AASI is not only a parameter for arterial stiffness, but also a parameter for BP variability

Association Between Inappropriateness of Left Ventricular Mass and Left Ventricular Diastolic Dysfunction: A Study Using the Tissue Doppler Parameter, E/E'

Background and Objectives: The structural significance of the inappropriateness of left ventricular mass (iLVM) is known to be an important prognostic factor for cardiovascular events; however, the functional changes associated with iLVM have not been established. This study was performed to determine if diastolic dysfunction is associated with iLVM using a tissue Doppler technique. Subjects and Methods: Three hundred sixty consecutive subjects, including 221 hypertension patients from the echocardiography database, were analyzed. Regarding the appropriateness of left ventricular (LV) mass, an observed/predicted ratio of IV mass (OPR) > 130% was defined as inappropriate. Echocardiographic parameters, including early diastolic peak velocity (E)/late diastolic peak velocity (A), deceleration time (DT), isovolumetric relaxation time (IVRT), and E/early mitral annulus velocity (E'), were compared between the appropriate LV mass (aLVM) group and the iLVM group. Results: Among transmitral flow parameters, only the E velocity was negatively correlated with the OPR when adjusted for age (adjusted r=-0.107, p=0.04). Based on multiple regression analysis, the OPR (??=0.163, p=0.003), as well as age (??=0.286, p=0.0001), systolic blood pressure (??=0.120, p=0.019), fasting blood glucose (??=0.098, p=0.042), and male gender (??=0.157, p=0.002) were independent factors determining E/E'. The cholesterol level was not an independent factor (??=-0.059, p=0.355). In the iLVM group (n=105), the adjusted E/E' was higher than in the aLVM group (n=255; 11.7 ?? 3.4 vs. 10.8 ?? 3.1, p=0.02), while the peak E flow velocity was significantly lower than in the aLVM group (70.9 ?? 15.1 vs. 75.5 ?? 17.6, p=0.03). Conclusion: Inappropriateness of LV mass is independently associated with increased E/E'. Thus, E/E' may be a useful parameter for the evaluation of diastolic dysfunction. Copyright ?? 2009 The Korean Society of Cardiology

The genetic architecture of type 2 diabetes

The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of heritability. To test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole genome sequencing in 2,657 Europeans with and without diabetes, and exome sequencing in a total of 12,940 subjects from five ancestral groups. To increase statistical power, we expanded sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support a major role for lower-frequency variants in predisposition to type 2 diabetes

Evaluation of Corrosion Resistance of Corrosion Inhibitors for Concrete Structures by Electrochemical Testing in Saturated Ca(OH)2 Solutions with NaCl and Na2SO4

Reinforcing steel maintains passivity in an alkaline concrete environment. However, the passive film on the steel can be destroyed as the concrete becomes acidic, which could induce the corrosion of reinforcing steel. Carbonates and sulfates destroy the concrete matrix and accelerate the penetration of hazardous ions, thereby deteriorating the structure. To alleviate the corrosion of internal reinforcing steel within concrete, corrosion inhibitors are most widely used. In this study, the effects of inorganic nitrite (lithium nitrite) and amino acid corrosion inhibitors (diethanolamine, methyl diethanolamine, and 4-aminobutyric) on corrosion resistance and the pH of the solution with various concentrations of Na2SO4 (0.89, 1.77 g/L) in saturated Ca(OH)2 that contained NaCl (0.98 g/L), which simulated the concrete environment, were investigated. The corrosion resistance of inhibitors was evaluated by corrosion potential, electrochemical impedance spectroscopy, and potentiodynamic techniques. The results indicated improvement of corrosion resistance by the addition of amino acid corrosion inhibitors. It was confirmed that the inhibitor adsorbed on the surface of the specimen and passivated to reduce the corrosion reaction. In addition, the 4-aminobutyric acid corrosion inhibitors had the corrosion protection efficiency of 67.87–77.80%, which is a higher value than that of the inorganic nitrite corrosion inhibitor (lithium nitrite: 69.36–75.93%) and other amino acid corrosion inhibitors (diethanolamine: 35.69–39.91%; methyl diethanolamine: 66.07–69.09%)

Concurrent activation of OsAMT1;2 and OsGOGAT1 in rice leads to enhanced nitrogen use efficiency under nitrogen limitation

© 2020 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd. Nitrogen (N) is a major factor for plant development and productivity. However, the application of nitrogenous fertilizers generates environmental and economic problems. To cope with the increasing global food demand, the development of rice varieties with high nitrogen use efficiency (NUE) is indispensable for reducing environmental issues and achieving sustainable agriculture. Here, we report that the concomitant activation of the rice (Oryza sativa) Ammonium transporter 1;2 (OsAMT1;2) and Glutamate synthetase 1 (OsGOGAT1) genes leads to increased tolerance to nitrogen limitation and to better ammonium uptake and N remobilization at the whole plant level. We show that the double activation of OsAMT1;2 and OsGOGAT1 increases plant performance in agriculture, providing better N grain filling without yield penalty under paddy field conditions, as well as better grain yield and N content when plants are grown under N limiting in field conditions. Combining OsAMT1;2 and OsGOGAT1 activation provides a good breeding strategy for improving plant growth, nitrogen use efficiency and grain productivity, especially under nitrogen limitation, through the increment of both nitrogen uptake and assimilation11sci

Mechanical Behavior of Free-Standing Fuel Cell Electrodes on Water Surface

Fundamental understanding of the mechanical behavior of polymer electrolyte fuel cell electrodes as free-standing materials is essential to develop mechanically robust fuel cells. However, this has been a significant challenge due to critical difficulties, such as separating the pristine electrode from the substrate without damage and precisely measuring the mechanical properties of the very fragile and thin electrodes. We report the mechanical behavior of free-standing fuel cell electrodes on the water surface through adopting an innovative ice-assisted separation method to separate the electrode from decal transfer film. It is found that doubling the ionomer content in electrodes increases not only the tensile stress at the break and the Young’s modulus (<i>E</i>) of the electrodes by approximately 2.1–3.5 and 1.7–2.4 times, respectively, but also the elongation at the break by approximately 1.5–1.7 times, which indicates that stronger, stiffer, and tougher electrodes are attained with increasing ionomer content, which have been of significant interest in materials research fields. The scaling law relationship between Young’s modulus and density (ρ) has been unveiled as <i>E</i> ∼ ρ^1.6, and it is compared with other materials. These findings can be used to develop mechanically robust electrodes for fuel cell applications

Stable Subloop Behavior in Ferroelectric Si-Doped HfO2

The recent demand for analogue devices for neuromorphic applications requires modulation of multiple nonvolatile states. Ferroelectricity with multiple polarization states enables neuromorphic applications with various architectures. However, deterministic control of ferroelectric polarization states with conventional ferroelectric materials has been met with accessibility issues. Here, we report unprecedented stable accessibility with robust stability of multiple polarization states in ferroelectric HfO2. Through the combination of conventional voltage measurements, hysteresis temperature dependence analysis, piezoelectric force microscopy, first-principles calculations, and Monte Carlo simulations, we suggest that the unprecedented stability of intermediate states in ferroelectric HfO2 is due to the small critical volume size for nucleation and the large activation energy for ferroelectric dipole flipping. This work demonstrates the potential of ferroelectric HfO2 for analogue device applications enabling neuromorphic computing

BL-11C Micro-MX: a high-flux microfocus macromolecular-crystallography beamline for micrometre-sized protein crystals at Pohang Light Source II

BL-11C, a new protein crystallography beamline, is an in-vacuum undulator-based microfocus beamline used for macromolecular crystallography at the Pohang Accelerator Laboratory and it was made available to users in June 2017. The beamline is energy tunable in the range 5.0–20 keV to support conventional single- and multi-wavelength anomalous-dispersion experiments against a wide range of heavy metals. At the standard working energy of 12.659 keV, the monochromated beam is focused to 4.1 µm (V) × 8.5 µm (H) full width at half-maximum at the sample position and the measured photon flux is 1.3 × 1012 photons s−1. The experimental station is equipped with a Pilatus3 6M detector, a micro-diffractometer (MD2S) incorporating a multi-axis goniometer, and a robotic sample exchanger (CATS) with a dewar capacity of 90 samples. This beamline is suitable for structural determination of weakly diffracting crystalline substances, such as biomaterials, including protein, nucleic acids and their complexes. In addition, serial crystallography experiments for determining crystal structures at room temperature are possible. Herein, the current beamline characteristics, technical information for users and some recent scientific highlights are described.11Nsciescopu