3,688 research outputs found
Group Based Trajectories Of Blood Pressure Components From Adulthood To Elderly In Chinese Workers
Objective: The study aimed to identify trajectories of systolic blood pressure (SBP),
diastolic blood pressure (DBP), and pulse pressure (PP) in Chinese adult workers from ages 18 to 81 years.
Methods: Analysis was conducted with a longitudinal data from Qingdao Port Health and Nutrition Examination Survey. This is a prospective study of employees of China\u27s Qingdao Port Company that was initiated in 1999 and has been collecting annual measure of blood pressure. For our analysis, we focused on the cohort from 2000 to 2011. A group-based trajectory modeling was adopted to identify patterns of blood pressure over the lifespan. The dual model was used to jointly estimate the trajectories of two distinct, but related longitudinal outcome series.
Results: Five trajectory patterns were identified from dual trajectory model of systolic blood pressure and pulse pressure, and diastolic blood pressure and pulse pressure. Systolic blood pressure kept increasing over time whereas diastolic blood pressure gradually increased then decreased in older ages. Pulse pressure began to increase in middle age and rose more steeply subsequently. In the dual model, the posterior probability of being assigned to a distinct group for one outcome was influenced by the membership in the group of the other outcome that was modeled simultaneously. The most interesting finding was that the group membership assignment in single trajectory model remained the same in dual trajectory model only for systolic blood pressure.
Conclusion: Classifying individuals into unobserved latent trajectory groups allow us to gain a better understanding of the determinants of blood pressure patterns and lead to more personalized treatment and prevention plans among Chinese adult workers
The First Room-Temperature Ambient-Pressure Superconductor
For the first time in the world, we succeeded in synthesizing the
room-temperature superconductor ( K, 127C) working at
ambient pressure with a modified lead-apatite (LK-99) structure. The
superconductivity of LK-99 is proved with the Critical temperature (),
Zero-resistivity, Critical current (), Critical magnetic field (),
and the Meissner effect. The superconductivity of LK-99 originates from minute
structural distortion by a slight volume shrinkage (0.48 %), not by external
factors such as temperature and pressure. The shrinkage is caused by Cu
substitution of Pb(2) ions in the insulating network of Pb(2)-phosphate
and it generates the stress. It concurrently transfers to Pb(1) of the
cylindrical column resulting in distortion of the cylindrical column interface,
which creates superconducting quantum wells (SQWs) in the interface. The heat
capacity results indicated that the new model is suitable for explaining the
superconductivity of LK-99. The unique structure of LK-99 that allows the
minute distorted structure to be maintained in the interfaces is the most
important factor that LK-99 maintains and exhibits superconductivity at room
temperatures and ambient pressure
Comparison Of Interpolation Technique For Rain Gauge Data Through The Distributed Rainfall-Runoff Model
Precipitation estimated from different measuring techniques such as rain gauge, radar and satellite have some similarities, but there are also differences among them. For example, techniques based on radar and satellite data underestimate rainfall than those using rain gauge data. In addition, many different interpolation techniques have been used to measure spatial pattern of precipitation but it is still difficult to have an accurate pattern by any one of them. The differences between the rainfall estimates from different techniques vary seasonally as well as regionally so that the radar or satellites are not directly applied into hydrologic analysis. In this regard, a main objective of this study is to develop a systematic way to interpolate ground rain gauge using discharge data from distributed rainfall-runoff model The spatial rainfall patterns estimated from the interpolation methods will be evaluated with the object function to minimize the difference between observed and estimated discharge. In other words, this study seeks to identify the optimal spatial pattern in rain field that can generate a similar pattern of observed discharge through the distributed rainfall-runoff model. This study will compare the spatial pattern from different types of climate systems and different seasons derived from different interpolation methods may help to validate the proposed algorithms
Onion peel extracts ameliorate hyperglycemia and insulin resistance in high fat diet/streptozotocin-induced diabetic rats
<p>Abstract</p> <p>Background</p> <p>Quercetin derivatives in onions have been regarded as the most important flavonoids to improve diabetic status in cells and animal models. The present study was aimed to examine the hypoglycemic and insulin-sensitizing capacity of onion peel extract (OPE) containing high quercetin in high fat diet/streptozotocin-induced diabetic rats and to elucidate the mechanism of its insulin-sensitizing effect.</p> <p>Methods</p> <p>Male Sprague-Dawley rats were fed the AIN-93G diet modified to contain 41.2% fat and intraperitoneally injected with a single dose of streptozotocin (40 mg/kg body weight). One week after injection, the rats with fasting blood glucose levels above 126 mg/dL were randomly divided into 4 groups to treat with high fat diet containing 0 (diabetic control), 0.5, or 1% of OPE or 0.1% quercetin (quercetin equivalent to 1% of OPE) for 8 weeks. To investigate the mechanism for the effects of OPE, we examined biochemical parameters (insulin sensitivity and oxidative stresses) and protein and gene expressions (pro-inflammatory cytokines and receptors).</p> <p>Results</p> <p>Compared to the diabetic control, hypoglycemic and insulin-sensitizing capability of 1% OPE were demonstrated by significant improvement of glucose tolerance as expressed in incremental area under the curve (<it>P </it>= 0.0148). The insulin-sensitizing effect of OPE was further supported by increased glycogen levels in liver and skeletal muscle (<it>P </it>< 0.0001 and <it>P </it>= 0.0089, respectively). Quantitative RT-PCR analysis showed increased expression of insulin receptor (<it>P </it>= 0.0408) and GLUT4 (<it>P </it>= 0.0346) in muscle tissues. The oxidative stress, as assessed by superoxide dismutase activity and malondialdehyde formation, plasma free fatty acids, and hepatic protein expressions of IL-6 were significantly reduced by 1% OPE administration (<it>P </it>= 0.0393, 0.0237, 0.0148 and 0.0025, respectively).</p> <p>Conclusion</p> <p>OPE might improve glucose response and insulin resistance associated with type 2 diabetes by alleviating metabolic dysregulation of free fatty acids, suppressing oxidative stress, up-regulating glucose uptake at peripheral tissues, and/or down-regulating inflammatory gene expression in liver. Moreover, in most cases, OPE showed greater potency than pure quercetin equivalent. These findings provide a basis for the use of onion peel to improve insulin insensitivity in type 2 diabetes.</p
Application of Copula-Based Markov Model to Generate Monthly Precipitation
Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv
Methanoldinitrato[N-(2-pyridylmethylene)aniline]copper(II)
The Cu atom in the title compound, [Cu(NO3)2(C12H10N2)(CH3OH)], adopts a square-pyramidal geometry, being ligated by two N atoms of the bidentate N-(2-pyridylmethylene)aniline (ppma) ligand, two O atoms of NO3 ligands and one O atom of a methanol molecule, which occupies the apical position. The phenyl ring on the ppma ligand is twisted out of the pyridine plane, forming a dihedral angle of 42.9 (1)°. In the crystal, intermolecular O—H⋯O hydrogen bonds between methanol and NO3 ligands form an extensive one-dimensional network extending parallel to [100]
The effect of ephedrine on intraoperative hypothermia
BACKGROUND: Prevention of intraoperative hypothermia has become a standard of operative care. Since ephedrine has a thermogenic effect and it is frequently used to treat hypotension during anesthesia, this study was designed to determine the effect of ephedrine on intraoperative hypothermia of patients who are undergoing spine surgery.
METHODS: Twenty-four patients were randomly divided to receive an ephedrine (the ephedrine group, n = 12) or normal saline (the control group, n = 12) infusion for 2 h. The esophageal temperature (the core temperature), the index finger temperature (the peripheral temperature) and the hemodynamic variables such as the mean blood pressure and heart rate were measured every 15 minutes after the intubation.
RESULTS: At the end of the study period, the esophageal temperature and hemodynamic variables were significantly decreased in the control group, whereas those in the ephedrine group were stably maintained. The index finger temperature was significantly lower in the ephedrine group compared to that in the control group, suggesting the prevention of core-to-peripheral redistribution of the heat as the cause of temperature maintenance.
CONCLUSIONS: An intraoperative infusion of ephedrine minimized the decrease of the core temperature and it stably maintained the hemodynamic variables during spine surgery with the patient under general anesthesia.ope
Input of terrestrial organic matter linked to deglaciation increased mercury transport to the Svalbard fjords
Deglaciation has accelerated the transport of minerals as well as modern and ancient organic matter from land to fjord sediments in Spitsbergen, Svalbard, in the European Arctic Ocean. Consequently, such sediments may contain significant levels of total mercury (THg) bound to terrestrial organic matter. The present study compared THg contents in surface sediments from three fjord settings in Spitsbergen: Hornsund in the southern Spitsbergen, which has high annual volume of loss glacier and receives sediment from multiple tidewater glaciers, Dicksonfjorden in the central Spitsbergen, which receives sediment from glacifluvial rivers, and Wijdefjorden in the northern Spitsbergen, which receive sediments from a mixture of tidewater glaciers and glacifluvial rivers. Our results showed that the THg (52 +/- 15 ng g(-1)) bound to organic matter (OM) was the highest in the Hornsund surface sediments, where the glacier loss (0.44 km(3) yr(-1)) and organic carbon accumulation rates (9.3 similar to 49.4 g m(-2) yr(-1)) were elevated compared to other fjords. Furthermore, the delta C-13 (-27 similar to -24 parts per thousand) and delta S-34 values (-10 similar to 15 parts per thousand) of OM indicated that most of OM were originated from terrestrial sources. Thus, the temperature-driven glacial melting could release more OM originating from the meltwater or terrestrial materials, which are available for THg binding in the European Arctic fjord ecosystems.11Ysciescopu
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