Increasing evidence supports the association between hyperuricemia and incident chronic kidney disease (CKD); however, there are conflicting data regarding the role of hyperuricemia in the ...progression of CKD. This study retrospectively assessed the longitudinal association between uric acid (UA) level and CKD progression in a Chinese population lived in Taiwan.
Patients with physician diagnosis of hyperuricemia or receiving urate-lowering therapy between 2003 and 2005 were identified in the electronic medical records (EMR) of a tertiary medical center and were followed up until December 31, 2011. Patients were divided into four UA categories at the cut-off 6, 8, and 10 mg/dL. CKD progression was estimated by the change of estimated glomerular filtration rate (eGFR) in the linear mixed models. Kidney failure was defined as an eGFR less than 15 mL/min/1.73 m2 or requiring renal replacement therapy.
A total of 739 patients were analyzed. In the full-adjusted model, patients with a baseline UA level ≥6 mg/dL had greater decline in eGFR ((β = -9.6, 95% CI -16.1, -3.1), comparing to those with a UA level less than 6 mg/dL. When stratifying patients into four UA categories, all three hyperuricemia categories (UA6-8, 8-10, ≥10 mg/dL) associated with a greater decline in eGFR over the follow-up period with an increasing dose-response, comparing to the lowest UA category. The risk of progression to renal failure increased 7% (hazard ratio 1.07, 95% CI 1.00, 1.14) for each 1mg/dL increase in baseline UA level. The influences of hyperuricemia on eGFR decline and the risk of kidney failure were more prominent in patients without proteinuria than those with proteinuria.
Our study showed a higher uric acid level is associated with a significant rapid decline in eGFR and a higher risk of kidney failure, particularly in patients without proteinuria. Our findings suggest hyperuricemia is a potential modifiable factor of CKD progression.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To investigate the effectiveness of a school-based program promoting outdoor activities in Taiwan for myopia prevention and to identify protective light intensities.
Multi-area, cluster-randomized ...intervention controlled trial.
A total 693 grade 1 schoolchildren in 16 schools participated. Two hundred sixty-seven schoolchildren were in the intervention group and 426 were in the control group.
Initially, 24 schools were randomized into the intervention and control groups, but 5 and 3 schools in the intervention and control groups, respectively, withdrew before enrollment. A school-based Recess Outside Classroom Trial was implemented in the intervention group, in which schoolchildren were encouraged to go outdoors for up to 11 hours weekly. Data collection included eye examinations, cycloplegic refraction, noncontact axial length measurements, light meter recorders, diary logs, and questionnaires.
Change in spherical equivalent and axial length after 1 year and the intensity and duration of outdoor light exposures.
The intervention group showed significantly less myopic shift and axial elongation compared with the control group (0.35 diopter D vs. 0.47 D; 0.28 vs. 0.33 mm; P = 0.002 and P = 0.003) and a 54% lower risk of rapid myopia progression (odds ratio, 0.46; 95% confidence interval CI, 0.28-0.77; P = 0.003). The myopic protective effects were significant in both nonmyopic and myopic children compared with controls. Regarding spending outdoor time of at least 11 hours weekly with exposure to 1000 lux or more of light, the intervention group had significantly more participants compared with the control group (49.79% vs. 22.73%; P < 0.001). Schoolchildren with longer outdoor time in school (≥200 minutes) showed significantly less myopic shift (measured by light meters; ≥1000 lux: 0.14 D; 95% CI, 0.02-0.27; P = 0.02; ≥3000 lux: 0.16 D; 95% CI, 0.002-0.32; P = 0.048).
The school-based outdoor promotion program effectively reduced the myopia change in both nonmyopic and myopic children. Outdoor activities with strong sunlight exposure may not be necessary for myopia prevention. Relatively lower outdoor light intensity activity with longer time outdoors, such as in hallways or under trees, also can be considered.
The objective of this study is to quantify the effect of the spatial variability of soil properties on site response and ground motion coherency. A 2D random field theory is used to simulate soil ...parameters, including shear wave velocity (Vs) and nonlinear stress–strain curves. Different levels of spatial variability are controlled by coefficient of variation (COV) and correlation length (CL). The wave prorogation is simulated through the 2D finite difference software FLAC2D. Different types of analysis conditions, such as 1D or 2D model, linear or nonlinear analysis, and input motion, are investigated. The increase of Vs variability leads to a decrease in the mean amplification ratio (surface response spectrum to bedrock response spectrum) but an increase in its variation. The effect of the variability of soil nonlinearity on the mean amplification ratio is marginal compared with that induced by Vs variability. However, as the ground motion intensities increase (or more nonlinearity induced), the standard deviation of the simulation normalized by the baseline response increases. Compared with the 2D result, the 1D site response analysis that is commonly used in practice may potentially underestimate the mean amplification ratio but overestimate its variability due to the ignorance of the horizontal soil property variability. In the evaluation of the spatially correlated site response, the ground motion coherency decays significantly, as the COV of Vs and the ground motion intensity increase. The effect of CL on ground motion coherency is minor and limited to a separation distance within two‐times of CL. Therefore, a coherency model, which eliminates the CL term but includes the ground motion intensity (i.e., nonlinear effect) parameter, is proposed in this study. It is revealed to yield a better agreement with the simulation results than other coherency models.
In this study, a series of cyclic triaxial tests were conducted on two poorly graded sands with different particle shapes. The experimental results were integrated with test results reported in the ...literature to construct a comprehensive database for investigating the effects of particle shape and relative density on excess pore water pressure (EPWP) generation. The sand types in the database were divided into three groups based on the particle shape: subrounded, subangular, and angular. The test results showed that the particle shape and relative density influenced the axial strain development and EPWP generation during undrained cyclic loading. As the relative density increased, the effect of the particle angularity on the shape of the EPWP generation curves decreased. The normalized EPWP generation curves of the subangular particles (C306 sand) exhibited a strong dependence on the relative density. However, the angular and subrounded particles exhibited a weaker influence than the subangular particles on EPWP change for different relative densities. A model was established to predict the EPWP generation with variations in the particle shape and relative density.
•A study that discussed the influences of relative density (Dr) and particle shapes on the excess pore water pressure (EPWP) generation curves.•A comprehensive data base of EPWP generation curves was built based on the data from literatures and this study.•Through distinguishing cyclic mobility and flow liquefaction, the excess pore water pressure generation curves were categorized into three different groups referring to different particle shapes.•A model was proposed in this study to simulate the EPWP generation curves based on particle shapes and Drs, and the predictive results were also shown.
A vertical-to-horizontal (V/H) response spectral ratio of 2/3 is commonly adopted in earthquake engineering for assessing the magnitude of vertical motion. However, higher V/H ratios are found in ...some earthquake records. This study evaluates the factors that can influence the V/H ratio on the basis of vertical and horizontal site response analyses. Two sets of rock motions representing near-source and far-field conditions are propagated through four selected sites that vary in soil column thickness, groundwater table, soil type, and wave velocity profile. The V/H ratio on the ground surface is calculated and compared with that at the bedrock. Results show that the V/H ratio is amplified by the local site effect, and increases at low wave velocity and high intensity of input motion owing to the different nonlinearities presented in the vertical and horizontal directions. The groundwater table considerably varies the V/H ratio and should be considered in assessing the vertical motion or V/H ratio.
This study examined the progression of chronic kidney disease (CKD) by using average annual decline in estimated GFR (eGFR) and its risk factors in a 10-year follow-up CKD cohort.
A prospective, ...observational cohort study, 4600 individuals fulfilled the definition of CKD, with or without proteinuria, were followed for 10 years. The eGFR was estimated by the MDRD equation. Linear regression was used to estimate participants' annual decline rate in eGFR. We defined subjects with annual eGFR decline rate <1 ml/min/1.73 m2 as non-progression and the decline rate over 3 ml/min/1.73 m2 as rapid progression.
During the follow-up period, 2870 (62.4%) individuals had annual eGFR decline rate greater than 1 ml/min/1.73 m2. The eGFR decline rate was slower in individuals with CKD diagnosed over the age of 60 years than those with onset at a younger age. Comparing to subjects with decline rate <1 ml/min/1.73 m2/year, the odds ratio (OR) of developing rapid CKD progression for diabetes, proteinuria and late onset of CKD was 1.72 (95% CI: 1.48-2.00), 1.89(1.63-2.20) and 0.68 (0.56-0.81), respectively. When the model was adjusted for the latest CKD stage, comparing to those with CKD stage 1, patients with stage 4 and stage 5 have significantly higher risks for rapid progression (OR, 5.17 (2.60-10.25), 19.83 (10.05-39.10), respectively). However, such risk was not observed among patients with the latest CKD stage 2 and 3. The risk for incident ESRD was 17% higher for each 1 ml/min/1.73 m2 increasing in annual decline rate.
Not everyone with CKD develops ESRD after a 10-year follow-up. Absolute annual eGFR decline rate can help clinicians to better predict the progression of CKD. Individuals with renal function decline rate over 3 ml/min/1.73 m2/year require intensive CKD care.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Previous studies have revealed that coronary artery calcium is related to cardiovascular diseases and mortality. However, most studies have been conducted in Western countries and have excluded ...patients with pre-existing heart disease. We investigated the association between coronary artery calcium (CAC) and all-cause mortality in an Asian cohort and in subgroups stratified by age, sex, smoking, obesity, diabetes, cardiovascular disease, blood pressure, and biochemical parameters. We conducted a retrospective cohort study on 4529 health examinees who underwent multidetector computed tomography in a tertiary medical center in Taiwan between 2011 and 2016. The mean follow-up was 3.5 years. Cox regression was used to estimate the relative hazards of death. Stratified analyses were performed. The all-cause mortality rates were 2.94, 4.88, 17.6, and 33.1 per 1000 person-years for CAC scores of 0, 1-100, 101-400, and >400, respectively. The multivariable adjusted hazard ratios (95% confidence intervals CIs) for all-cause mortality were 0.95 (0.53, 1.72), 1.87 (0.89, 3.90), and 3.05 (1.46, 6.39) for CAC scores of 1-100, 101-400, and >400, respectively, relative to a CAC score of 0. Compared with CAC less than or equal to 400, the HRs (95% CIs) for CAC > 400 were 6.46 (2.44, 17.15) and 1.94 (1.00, 3.76) in younger and older adults, respectively, indicating that age was a moderating variable (p = 0.02). High CAC scores were associated with increased all-cause mortality. Although older adult patients had higher risks of death, the relative risk of death for patients with CAC > 400 was more prominent in people younger than 65 years.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Frequency-dependent equivalent linear (FD-EQL) site response analysis methods, developed as potential substitutes for the EQL procedure to better simulate the nonlinear soil response, have been ...reported to overpredict the high-frequency wave propagation. Modified procedures proposed to overcome this limitation have demonstrated to improve the fits with the nonlinear analysis results. The method has not yet been applied to perform a deconvolution analysis, where a conventional EQL analysis often fails to converge or provide reliable estimate. The conventional EQL procedure and one of the modified FD-EQL method, which uses an empirical factor f to interpolate the strain spectrum between the EQL and FD-EQL outputs, are used to perform a series of deconvolution analyses using an idealized 1000 m profile and twelve Kik-net downhole arrays. The residuals of recorded and deconvoluted motions are shown to increase with strain for the EQL method even when using the recommended frequency cut-off. For the FD-EQL method, the range of f recommended for convolution analyses is shown to provide unrealistic responses in performing deconvolution analyses. A new range that produces unbiased residuals for all strain amplitudes is proposed. Comparisons highlight that the modified FD-EQL yields reliable predictions of the within motion for all profiles and motion intensities, automatically suppressing the amplification of high-frequency noise typically accompanied in a deconvolution analysis.
Vertical ground motion significantly affects the seismic response of engineering structures, particularly nuclear power plants and dams. However, most ground motion predictions or site response ...analyses focus on horizontal ground motion. As a result, knowledge of the characteristics of vertical ground motions is inadequate. In this study, a benchmark approach for equivalent linear vertical site response analyses is developed, with focus on the modeling of soil nonlinearity. The modeled soil exhibits different nonlinear behavior in the vertical direction depending on the saturation condition (i.e., above or below the groundwater table). Moreover, the vertical nonlinearity is different from that observed in the horizontal direction. The vertical ground responses predicted by the proposed approach are generally consistent with downhole measurements associated with different geological conditions, groundwater tables, and shaking intensities.
•A benchmark approach of site response analysis for vertical motions is developed, especially focusing on the modeling of soil nonlinearity.•Given the saturation condition, the modeled soil exhibits different nonlinear behavior and energy dissipation based on the commonly used soil nonlinear curve.•The approach can capture the nonlinearity and damping of soil in the vertical direction as observed in the previous studies.•The vertical ground responses predicted by the proposed approach generally agree with the downhole measurements associated with different geological conditions, ground water tables, and intensities of shaking.
Two salicyaldimine ligands, HsalCl-3-py and HsalOMe-3-py, functionalized with the pyridyl group on the imine side and their Zn and Cu complexes with a general formula ML2, where M = Zn, ...L = salCl-3-py (1), salOMe-3-py (2); M = Cu, L = salCl-3-py (3), salOMe-3-py (4), have been synthesized and characterized by nuclear magnetic resonance (NMR) spectroscopy, mass spectroscopy (MS), infrared (IR) spectroscopy, elemental analysis (EA), scanning electron microscope (SEM) and further by single-crystal X-ray diffraction analysis and X-ray powder diffraction (XRPD). The crystal structures of Zn– and Cu–salicyaldimine complexes exhibited that the M(II) center is coordinated by two N,O-chelated salicyaldimine ligands in a square-planar geometry, and two further pyridyl donating groups from two neighboring molecules at the axial positions, resulted in self-aggregation to form a two-dimensional (4,4)-sheet. Interestingly, apart from the strong M–N(pyridyl) coordination bond, the weak CH⋯N(pyridyl) hydrogen bonding interactions are simultaneously formed between the pyridyl N-donor and one pyridyl hydrogen of the equatorial salicyaldimine ligand. The electronic absorption spectra of the Zn– and Cu–salicyaldimine complexes in methanol solutions showed the appearance of a metal-to-ligand charge transfer absorption other than the intraligand charge transfer transitions after the complexation of azomethine (–CN–) with M(II) center. On the other hand, salicyaldimine ligands and Cu–salicyaldimine complexes showed no or weak fluorescence emissions. By contrast, Zn–salicyaldimine complexes emitted intense cyan and green light fluorescence in both solid-state and methanol solutions. Noteworthy, transmetallation of Zn–salicyaldimine complexes with Cu2+ ions would be achieved, producing corresponding Cu–salicyaldimine complexes. This implies the stronger binding ability of Cu2+ than that of Zn2+ to salicyaldimine ligands.
Transmetallation of fluorescent Zn–salicyaldimine complexes with Cu2+ ions yield corresponding non-fluorescent Cu analogues; all these Zn and Cu complexes show the simultaneous occurrence of both M–N(py) bond and CH⋯N(py) contact about a single pyridyl N-donor. Display omitted
•Zn/Cu–N coordination and CH⋯N contact are simultaneously formed about a single N-donor.•Discrete mononuclear molecules of complexes 1–4 form extended (4,4)-sheet in crystal phase.•Zn–salicyaldimine complexes 1 and 2 emit cyan and green light fluorescence, respectively.•Transmetallation of Zn–salicyaldimine complexes with Cu2+ ions is achieved.
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