108 research outputs found

    Prediction of Spot Price of Iron Ore Based on PSR-WA-LSSVM Combined Model

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    Aiming at the problems that the existing single time series models are not accurate and robust enough when it comes to forecasting the iron ore prices and the parameters of the traditional LSSVM model are difficult to determine, we propose a combined model based on Phase Space Reconstruction (PSR), wavelet transform and LSSVM (PSR-WA-LSSVM) to tackle these issues. ARIMA model, LSTM model, PSR-LSSVM model, and PSR-WA-LSSVM models were used for contrast simulation to forecast the spot price data of 61.5%PB powder from January 30, 2019, to February 1, 2021, in Ningbo Zhoushan port. The experimental results show that the PSR-WA-LSSVM combination model achieves better prediction results. At the same time, the model has a good performance in the multistep prediction of the iron ore price

    Effect of early exogenous supplementation of rhIGF-1 on oxygen-induced retinopathy in a mice model of prematurity, and on expressions of IGF-1 and VEGF

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    Purpose: To investigate the effect of early exogenous supplementation of recombinant human insulinlike growth factor (rhIGF-1) on oxygen-induced mouse model of retinopathy of prematurity (ROP). Methods: Three groups of healthy SPF grade C57BL/6 mice were used in this study, with 20 mice in each group. Hyperoxia saline (HS) and hyperoxia rhIGF-1 (HrGF) groups were placed in a closed oxygen chamber for one week and returned to the normal environment on the 15th day. The hyperoxia rhIGF-1 (HrGF) group was intraperitoneally injected with rhIGF-1 (1.5 mg/kg), while mice in high-oxygen saline (HS) group received normal saline. The air group (AG) was untreated. Changes in retinal blood vessel distributions, expression levels of serum IGF-1 and VEGF, and retinal IGF-1 and VEGF were determined. Results: On day 20, pronounced neo-vascularization was observed, but the distribution was disordered. Serum IGF-1 levels in AG and HrGF were significantly higher than that in HS group, but VEGF level was lower in HS mice (p < 0.05). VEGF level in hyperoxia rhIGF-1 group on days 11 and 15 decreased, relative to control value, while retinal IGF-1 and VEGF in AG and hyperoxia rhIGF-1 mice were elevated, relative to corresponding values in HS mice (p < 0.05). Conclusion: Early exogenous supplementation of rhIGF-1 exerts a therapeutic effect on ROP. Thus, rhIGF-1 may be a potential drug regimen for ROP in clinics

    Focusing MSs for High-Gain Antenna Applications

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    Recently, metasurfaces (MSs) have continuously drawn significant attentions in the area of enhancing the performances of the conventional antennas. Thereinto, focusing MSs with hyperbolic phase distributions can be used for designing high-gain antennas. In this chapter, we first design a new reflected MS and use a spiral antenna as the feeding source to achieve a wideband high-gain antenna. On this basis, we propose a bi-layer reflected MS to simultaneously enhance the gain and transform the linear polarization to circular polarization of the Vivaldi antenna. Then, we proposed a multilayer transmitted MS and use it to enhance the gain of a patch antenna. This kind of high-gain antenna eliminates the feed-block effect of the reflected ones but suffer from multilayer fabrication. To conquer this problem, we finally propose a single-layer transmitted focusing MS by grouping two different kinds of elements and use it to successfully design a low-profile high-gain antenna

    High Performance Metasurface Antennas

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    Recently, metasurfaces (MSs) have received tremendous attention because their electromagnetic properties can be controlled at will. Generally, metasurface with hyperbolic phase distributions, namely, focusing metasurface, can be used to design high-gain antennas. Besides, metasurface has the ability of controlling the polarization state of electromagnetic wave. In this chapter, we first propose a new ultrathin broadband reflected MS and take it into application for high-gain planar antenna. Then, we propose multilayer multifunctional transmitted MSs to simultaneously enhance the gain and transform the linear polarization to circular polarization of the patch antenna. This kind of high-gain antenna eliminates the feed-block effect of the reflected ones

    FastPop: a rapid principal component derived method to infer intercontinental ancestry using genetic data.

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    BACKGROUND: Identifying subpopulations within a study and inferring intercontinental ancestry of the samples are important steps in genome wide association studies. Two software packages are widely used in analysis of substructure: Structure and Eigenstrat. Structure assigns each individual to a population by using a Bayesian method with multiple tuning parameters. It requires considerable computational time when dealing with thousands of samples and lacks the ability to create scores that could be used as covariates. Eigenstrat uses a principal component analysis method to model all sources of sampling variation. However, it does not readily provide information directly relevant to ancestral origin; the eigenvectors generated by Eigenstrat are sample specific and thus cannot be generalized to other individuals. RESULTS: We developed FastPop, an efficient R package that fills the gap between Structure and Eigenstrat. It can: 1, generate PCA scores that identify ancestral origins and can be used for multiple studies; 2, infer ancestry information for data arising from two or more intercontinental origins. We demonstrate the use of FastPop using 2318 SNP markers selected from the genome based on high variability among European, Asian and West African (African) populations. We conducted an analysis of 505 Hapmap samples with European, African or Asian ancestry along with 19661 additional samples of unknown ancestry. The results from FastPop are highly consistent with those obtained by Structure across the 19661 samples we studied. The correlations of the results between FastPop and Structure are 0.99, 0.97 and 0.99 for European, African and Asian ancestry scores, respectively. Compared with Structure, FastPop is more efficient as it finished ancestry inference for 19661 samples in 16 min compared with 21-24 h required by Structure. FastPop also provided scores based on SNP weights so the scores of reference population can be applied to other studies provided the same set of markers are used. We also present application of the method for studying four continental populations (European, Asian, African, and Native American). CONCLUSIONS: We developed an algorithm that can infer ancestries on data involving two or more intercontinental origins. It is efficient for analyzing large datasets. Additionally the PCA derived scores can be applied to multiple data sets to ensure the same ancestry analysis is applied to all studies

    Phase I Study of the Tolerability and Pharmacokinetics of Palifermin in Children Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

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    The maximum tolerated dose of palifermin, a keratinocyte growth factor, in children is not known, and its pharmacokinetics in this population has not been well studied. This is a phase I study of palifermin was designed to evaluate its tolerability at doses of 40, 60, and 90 μg/kg/day in children age 2–18 years of age, receiving a myeloablative preparative regimen for allogeneic hematopoietic stem cell transplantation (HSCT). In each cohort, palifermin was given for 3 consecutive days before the preparative regimen and for 3 days after the stem cell infusion. Twelve patients were enrolled. Palifermin 90 μg/kg/day was tolerated in 6 patients without dose-limiting toxicity. All patients had at least 1 adverse event, mostly National Cancer Institute grade 1 or 2 severity. Skin rash, grade 2 or lower, was the most common adverse event, seen in 67% of patients. Only 3 patients (25%) had mucositis. The area under the concentration–time curve increased proportionally to the dose, and approximately 97% of palifermin exposure occurred in the first 24 hours after administration. Palifermin clearance increased linearly with body weight, supporting dosing by body weight. The mean clearance was 1893 mL/hour/kg, and it did not change significantly between administration of the first and last doses (P =.80). The mean elimination half-life was 4.6 hours. Our data show that palifermin was tolerated at a dose of 90 μg/kg/day, and exhibits linear pharmacokinetics in children undergoing allogeneic HSCT

    The Use of Integrative Therapies in Patients with Amyotrophic Lateral Sclerosis in Shanghai, China

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    Objective. To investigate the current use of integrative therapies (IT) in the treatment of patients with amyotrophic lateral sclerosis (ALS). Methods. A cross-sectional, multicenter clinical epidemiological survey was conducted in 12 hospitals in Shanghai. We investigated the type and frequency of IT use and determined whether the use of IT correlated with demographic, social, or disease-specific characteristics in our patient population. Results. A total of 231 (89.5%) of 258 patients with ALS were eligible for the study and 229 (99% of all) of 231 reported the use of at least one IT for the treatment of ALS. Vitamins and Chinese herb decoctions, Chinese herb compounds, massage therapy, and acupuncture were the 5 most commonly used therapies. There was a strong association between education level, income, and use of IT. A household income of more than 75,000 RMB ($49,995) correlated with multiple IT use, and married patients used IT more often than single individuals. The main reasons for using IT were to treat weakness and fatigue, muscle atrophy, the development of ALS, depression, insomnia, limb pain or numbness, and side effects associated with Riluzole. Conclusion. The use of IT is common in patients with ALS in Shanghai. Vitamins and TCM are the most used additional therapies and the widespread and largely unexamined use of IT for ALS requires more attention

    Height and body-mass index trajectories of school-aged children and adolescents from 1985 to 2019 in 200 countries and territories: a pooled analysis of 2181 population-based studies with 65 million participants

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    Summary Background Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents. Methods For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5–19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence. Findings We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9–10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing countries, but they became progressively less healthy compared with their comparators as they grew older by not growing as tall (eg, boys in Austria and Barbados, and girls in Belgium and Puerto Rico) or gaining too much weight for their height (eg, girls and boys in Kuwait, Bahrain, Fiji, Jamaica, and Mexico; and girls in South Africa and New Zealand). In other countries, growing children overtook the height of their comparators (eg, Latvia, Czech Republic, Morocco, and Iran) or curbed their weight gain (eg, Italy, France, and Croatia) in late childhood and adolescence. When changes in both height and BMI were considered, girls in South Korea, Vietnam, Saudi Arabia, Turkey, and some central Asian countries (eg, Armenia and Azerbaijan), and boys in central and western Europe (eg, Portugal, Denmark, Poland, and Montenegro) had the healthiest changes in anthropometric status over the past 3·5 decades because, compared with children and adolescents in other countries, they had a much larger gain in height than they did in BMI. The unhealthiest changes—gaining too little height, too much weight for their height compared with children in other countries, or both—occurred in many countries in sub-Saharan Africa, New Zealand, and the USA for boys and girls; in Malaysia and some Pacific island nations for boys; and in Mexico for girls. Interpretation The height and BMI trajectories over age and time of school-aged children and adolescents are highly variable across countries, which indicates heterogeneous nutritional quality and lifelong health advantages and risks
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