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The influence of pressure and environment on urban polyethylene (PE) gas pipeline makes structural deterioration and leaking to the pipeline and pipeline easy. This paper proposes an analysis method for optimizing Variational Mode Decomposition (VMD) algorithm. Firstly, the optimal bandwidth is obtained by using the adaptive weighted frequency band entropy (AFBE), and the optimal quadratic penalty factor is obtained by curve fitting. Then, the AFBE is used as the fitness function, and the optimal decomposition level is obtained by the optimized beetle whisker search algorithm. Experimental results show that the signal-to-noise ratio (SNR) is improved by 12.74% on average. [ABSTRACT FROM AUTHOR]

We study the set Γ consisting of univoque sequences, the set ʌ consisting of sequences in which the lengths of consecutive zeros and consecutive ones are bounded, and their frequency subsets Γa, Γa, Γa and ʌa, ʌa, ʌa consisting of sequences respectively in Γ and ʌ with frequency, lower frequency and upper frequency of zeros equal to some a ∊ [0, 1]. The Hausdorff dimension of all these sets are obtained by studying the dynamical system (ʌ(m), s) where s is the shiftmapandʌ(m) = Γ w ∊ {0, 1}N: w does not contain 0mor1m } for integer m = 3, studying the Bernoulli-type measures on ʌ(m) and finding out the unique equivalent s-invariant ergodic probability measure. [ABSTRACT FROM AUTHOR]

The response of the laminar premixed flame to a counterflowing non-thermal plasma jet has been studied experimentally and numerically. The plasma is driven by alternating current and sustained in a co-axial dielectric-barrier-discharge (DBD) generator. Particle tracking methods and optical diagnostics of flame emission provide spatio-temporal resolutions of the flow field and subsequent flame response. The deflection of the streamline and flame sheet due to hydrodynamic disturbances results in oscillation of the total heat release rate. Numerical analysis is performed by specifying the flow fluctuation using inflow boundary conditions, as well as solving the flow field and flame structure in the small cylindrical domain sandwiched between the opposed nozzle outlets. The contour plots of temperature and velocity vectors in the simulation solution verify that the flow fluctuation causes deflection, displacement, creases and localized quenching of the flame front. [ABSTRACT FROM AUTHOR]

The thermal ignition of a reacting boundary-layer flow over the hot surface of a wedge/cone with an unheated starting length, , is studied analytically and numerically. For the realistic situation of large activation energy reactions, a locally similar solution is derived and is found to agree well with the numerical solution within a wide range of , geometric angle and the Prandtl number, . An increase in is shown to reduce the minimum ignition distance, because the flow velocity is reduced by the viscous drag over the starting length so that the flow over the heated section is heated to a greater extent for the same distance. [ABSTRACT FROM AUTHOR]

Background:Birth weight percentiles by gestational age are important for assessing prenatal growth and predicting postnatal outcomes of newborns. Several countries have developed nation-specific birth weight references for twins, but China still lacks such references. Methods and results:Birth weight data for twins born between October 2006 and September 2015 were abstracted from the China National Population-based Birth Defects Surveillance System. A total of 54,786 live twin births aged ≥28 weeks of gestation without birth defects were included in the analysis. The LMS method was adopted to generate gestational age-specific birth weight percentiles and curves for male and female twins separately. Significant differences were observed between the current reference and other references developed for Chinese or non-Chinese twins. The neonatal mortality rate in this cohort was 12.3‰, and much higher rates at very early gestation weeks were identified in small-for-gestational-age twins grouped by the newly developed reference cutoffs. Conclusions:The established birth weight centiles represent the first birth weight norm for contemporary Chinese twins and can be a useful tool to assess growth of twins in clinical and research settings.Key MessagesThere have been no population-based birth weight percentiles for Chinese twins prior to this study. The established birth weight centiles for female and male twins are markedly lower than those for Chinese singletons. Twin-specific curves should be used for determining inappropriate for gestational age in twins rather than using existing singleton reference.The birth weight percentiles for twins differed significantly from those for non-Chinese twins. In addition to ethnic influences, the observed differences could be ascribed to variations in prenatal care, fetal or maternal nutrition status or other environmental factors.Neonatal mortality rates varied considerably among twins grouped by the newly developed reference percentiles. Small-for-gestational-age twins had much higher mortality than did appropriate-for-gestational-age twins, highlighting the need to reduce postnatal mortality by improving perinatal health care for twins. [ABSTRACT FROM PUBLISHER]

The oxidation of aluminium nanoparticles coupled with crystallisation of amorphous alumina shell is investigated through the thermogravimetric analyser and differential scanning calorimetry (TGA-DSC) and the transmission electron microscope (TEM). The thermogravimetric (TG) curves show stepwise shapes with temperature increase and could be divided into four stages. The reaction at the second stage is complex, including the simultaneous crystallisation of amorphous alumina (am-Al2O3) and Al oxidation. The crystallisation of am-Al2O3promotes the reaction through generating fast diffusion channels, like micro-cracks and grain boundaries in the oxide shell to accelerate the ionic diffusion. An enhancement factor (freact), which follows a power-law formula with the crystallisation rate, is introduced to quantify the impact of crystallisation on reaction. With heating rate increase, the second stage of TG curves shifts to the high temperature regime and the total weight gain at the second stage decreases slowly. A crystallisation-reaction model is constructed to fit and predict the weight gain after derivation of diffusivities and crystallisation kinetics. Modelling indicates that with heating rate rise, the mass increment at the second stage of TG curves decreases owing to the reduced reaction time, although the reaction is accelerated. The shift of TG curve to higher temperature is due to the polymorphic phase transition. Actually the derived kinetics of the crystallisation of amorphous alumina indicates that the polymorphic phase transformation mechanism works mainly below the heating rate of 3 K s–1. At higher heating rate, the melting of Al takes place firstly and the crystallisation of am-Al2O3follows to enhance the ionic diffusion. Therefore, when the heating rate is fast during ignition or combustion, the Al nanoparticles undergo both the melting of Al and the polymorphic phase transition of am-Al2O3to accelerate the reaction. [ABSTRACT FROM PUBLISHER]

The aim of this study is to analyze the research trends of medical informatics over the last 12 years. A new method based on MeSH terms was proposed to identify emerging topics and trends of medical informatics research. Informetric methods and visualization technologies were applied to investigate research trends of medical informatics. The metric of perspective factor (PF) embedding MeSH terms was appropriately employed to assess the perspective quality for journals. The emerging MeSH terms have changed dramatically over the last 12 years, identifying two stages of medical informatics: the 'medical imaging stage' and the 'medical informatics stage'. The focus of medical informatics has shifted from acquisition and storage of healthcare data by integrating computational, informational, cognitive and organizational sciences to semantic analysis for problem solving and clinical decision-making. About 30 core journals were determined by Bradford's Law in the last 3 years in this area. These journals, with high PF values, have relative high perspective quality and lead the trend of medical informatics. [ABSTRACT FROM AUTHOR]

Objective: The study was to evaluate neurotoxicity caused by antibiotics in dialysis patients, including incidence, clinical features, treatments and prognosis. Methods: In this retrospective study, we reviewed the medical records of 1066 dialysis patients (254 peritoneal dialysis [PD] cases and 812 hemodialysis [HD] cases) who also received intravenous antibiotics in our hospital during July 2006 - April 2012. Naranjo scale was used for estimating the probability of an adverse drug reaction. Results: The incidence of antibiotic-induced neurotoxicity was 5.66% in patients receiving HD, and 7.87% in patients receiving PD. There was no significant difference between the two dialysis modalities about the incidence of antibiotic-induced neurotoxicity ( p > 0.05). The risk factors included extremely old age, history of central nervous system disorder, low residual renal function, hypoalbuminemia, and the use of multiple antibiotics that share one mechanism. The neurotoxic antibiotics included cephalosporins, penicillins, carbapenems and quinolones in our study. Most patients could be properly diagnosed early according to their medical history, symptoms, signs, electroencephalography (EEG), other related auxiliary examination, and with the help of experienced neurologists. Most neurotoxic patients showed clinical improvement after the discontinuation of antibiotics and active treatment. Conclusions: The adverse neurotoxic effects of antibiotics were common in dialysis patients due to wide and incorrect usage. Neurotoxicity could be prevented in high-risk cases with dosage adjustments. Better prognosis can be achieved with early and proper diagnosis, decisive withdrawal, and aggressive treatment including enhanced HD. [ABSTRACT FROM AUTHOR]

Ergosterol 3-O-β-d-glucopyranoside (1a) and ergosterol 3-O-β-d-galactopyranoside (1b) were highly efficiently synthesized and evaluated for their inhibitory activities against two tumor cell lines. The structures of these compounds were extensively confirmed by 1H, 13C NMR, IR, and HRMS. Compounds 1a and 1b exhibited interesting cytotoxic profiles. The antitumor activity of compound 1a was higher than that of 1b. [ABSTRACT FROM AUTHOR]

The thin-layer chromatographic analysis of the crude oligosaccharides extracted from yacon revealed the presence of glucose, fructose, sucrose, 1-kestose and nystose. The qualitative and quantitative analysis was carried out on oligosaccharides by high pressure liquid chromatography and the results showed that the contents of d-glucose, fructose, sucrose, 1-kestose, nystose and 1-fructofuranosyl nystose in oligosaccharides were 38.30%, 16.44%, 14.58%, 12.29%, 12.17%, 6.20%, respectively. The content of the fructooligosaccharides in oligosaccharides was 30.66%. The crude oligosaccharides were separated and purified by silica gel column chromatography. The two fractions obtained from crude oligosaccharides were 1-kestose and nystose, which were identified by mass spectra. The yield of 1-kestose and nystose were 10.36% and 9.73%, respectively. The purity of 1-kestose was 82.9% and of nystose was 73.6%. [ABSTRACT FROM AUTHOR]

Background: Decreased plasma essential amino acid (EAA) levels, increased nonessential amino acid (NEAA) levels, and low EAA to NEAA ratio (E/NEAA) are common in peritoneal dialysis (PD) patients and may impact uremic complications. In the present study, we investigate the impact of keto acids–supplemented low–protein (sLP) diet on plasma amino acids (AAs) patterns in stable PD patients. Methods: This is a supplemental analysis of a previously published prospective and randomized trial. Thirty-nine PD patients selected from the original population were divided to receive either low (LP: 0.6–0.8 g/kg ideal body weight [IBW]/d, n = 13), keto acids–supplemented low- (sLP: 0.6–0.8 g/kg IBW/d + 0.12 g/kg IBW/d of keto acids, n = 12), or high- (HP: 1.0–1.2 g/kg IBW/d, n = 14) protein diets and followed for 1 year. Plasma AA patterns were assessed at baseline and 12 months using high-performance liquid chromatography. Results: Whereas there were no significant differences between the three groups at baseline, following 12 months, the E/NEAA had increased significantly in group sLP (0.58 ± 0.16 to 0.83 ± 0.20, p < 0.05), but was not different in either LP (0.62 ± 0.20 to 0.72 ± 0.13, p = ns) or HP (0.66 ± 0.14 to 0.74 ± 0.12, p = ns) group. This change in E/NEAA in group sLP was due to a significant decrease in NEAA concomitantly with maintained EAA levels, whereas in the other two groups, neither EAA nor NEAA changed significantly. Conclusions: A low-protein diet supplemented with keto acids significantly improved the pattern of plasma AA in prevalent PD patients. [ABSTRACT FROM AUTHOR]

Cardiovascular disease (CVD) remains the main cause of morbidity and mortality in patients with end-stage renal disease (ESRD). Although traditional risk factors, such as diabetes mellitus, hypertension, dyslipidemia and advanced age, are prevalent in ESRD patients they may not be sufficient by themselves to account for the high prevalence of CVD in patients with this condition. Thus, the search for other, non-traditional, risk factors that may be involved in the pathogenesis of uremic CVD has been an area of intense study. Data suggest that the accelerated atherosclerotic process of ESRD may involve several interrelated processes, such as oxidative stress, endothelial dysfunction and vascular calcification, in a milieu of constant low-grade inflammation. The cause(s) of inflammation in ESRD are multifactorial and, while it may reflect underlying CVD, an acute-phase reaction may also be a direct cause of vascular injury via several pathogenetic mechanisms. Available data suggest that pro-inflammatory cytokines play a central role in the genesis of both malnutrition and CVD in ESRD. Thus, it could be speculated that suppression of the vicious cycle of malnutrition, inflammation and atherosclerosis (MIA syndrome) would improve survival in dialysis patients. Recent evidence has demonstrated strong associations between inflammation and both increased oxidative stress and endothelial dysfunction in ESRD patients. As there is not yet any recognized, or even proposed, treatment for ESRD patients with chronic inflammation it would be of obvious interest to study the long-term effect of various anti-inflammatory treatment strategies on the nutritional and cardiovascular status as well as outcome of these patients. [ABSTRACT FROM AUTHOR]