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Polypropylene plastic (PP) was chosen as additives for the preparation of activated carbon (AC), considering that PP promotes pore formation during the preparation of AC. When the addition ratio of PP was 20%, AC having a maximum specific surface area of 1916.1 m2/g was prepared. Fourier transform–infrared spectroscopy (FT-IR) analysis exhibited the types of functional groups on the surface of AC, such as–OH, C=O, C–C, and –CH. The SEM analysis revealed the formation of disordered pores over the AC. Furthermore, iodine value of the AC is 1460 mg/g. Additionally, adsorption test revealed the AC is suitable for adsorbing methylene blue (MB). The adsorption equilibrium data of MB onto AC were most suitable for Redlich–Peterson model. The maximum adsorption capacity of the single layer was 476.88 mg/g, indicating that AC has high adsorption capacity. The kinetic data fitted well with the pseudo-second-order model.
Global Navigation Satellite System (GNSS) observations contain various errors, the separation and measurement of which is a popular research topic. Multipath effect on code measurements is investigated through the multipath combination, but carrier multipath error is small, and it is difficult to distinguish from other errors, such as hardware delay, carrier noise and satellite inherent biases. However, as the number of frequency points increases during the rapid development of GNSSs, it is possible to analyse the abovementioned errors in detail. Triple-frequency combination can be used to eliminate the first order ionospheric error, and a quad-frequency combination has one degree of freedom, which may be used to minimise carrier error effects. For this reason, an optimum method has been developed for multi-frequency GNSS code-multipath combination measurements, which has been verified by exploiting BeiDou System (BDS), three frequency data from an International GNSS Service (IGS) station and a city canyon as well as actual sampled quad-frequency data. By comparative analysis, we found that the fluctuations of an optimum triple-frequency combination are smaller than that of the non-optimum combination, which decreases the influence of inherent errors and biases on carrier phase. At the same time, second-order ionospheric error can be effectively eliminated as well. This provides a new code-multipath combination measurement optimisation methodology for future multi-frequency BDS and other GNSSs.
The aim of this retrospective study was to investigate the prognostic significance of pre-treatment immunological and nutritional statuses in patients with locally advanced gastric cancer (GC), and to use the risk factors to develop a predictive score. A total of 731 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015 were recruited into this retrospective study. On the basis of univariate and further multivariate Cox regression analyses, decreased pretreatment lymphocyte count (<1·5×109/litre) and prealbumin concentrations (<180 mg/l) were identified to be independently associated with poorer overall survival (OS) and disease-free survival (DFS). Low albumin concentrations (<33 g/l) were identified as an independent risk factor only for OS, but not for DFS. Thereafter, patients who had a decreased prealbumin concentration and lymphocyte count were given a combination of serum prealbumin concentration and lymphocyte count (Co-PaL) score of 2. Patients with only one or neither of these concentrations were given a Co-PaL score of 1 or 0, respectively. Both the OS and the DFS time were inversely related to the Co-PaL scores, and the differences among the three groups were all significant. In contrast, the prognosis did not differ significantly between patients with good nutrition and those with mild to moderate malnutrition according to the prognostic nutritional index. This study indicated that the simple scoring system could accurately predict the prognosis of patients who underwent gastrectomy for stage II/III GC. The score might be helpful in terms of clinical preoperative decision-making.
Healthcare-associated infections (HAIs) are a major worldwide public-health problem, but less data are available on the long-term trends of HAIs and antimicrobial use in Eastern China. This study describes the prevalence and long-term trends of HAIs and antimicrobial use in a tertiary care teaching hospital in Hefei, Anhui, China from 2010 to 2017 based on annual point-prevalence surveys. A total of 12 505 inpatients were included; 600 HAIs were recorded in 533 patients, with an overall prevalence of 4.26% and a frequency of 4.80%. No evidence was found for an increasing or decreasing trend in prevalence of HAI over 8 years (trend χ2 = 2.15, P = 0.143). However, significant differences in prevalence of HAI were evident between the surveys (χ2 = 21.14, P < 0.001). The intensive care unit had the highest frequency of HAIs (24.36%) and respiratory tract infections accounted for 62.50% of all cases; Escherichia coli was the most common pathogen (16.67%). A 44.13% prevalence of antimicrobial use with a gradually decreasing trend over time was recorded. More attention should be paid to potential high-risk clinical departments and HAI types with further enhancement of rational antimicrobial use.
Maternal dietary patterns and macronutrients intake have been shown to affect the development of gestational diabetes mellitus (GDM), but the findings are inconsistent. We aimed to identify maternal dietary patterns and examine their associations with GDM risk, and to evaluate the contributions of macronutrients intake to these associations. We included 2755 Chinese pregnant women from the Tongji Maternal and Child Health Cohort. Dietary intakes were assessed using a validated semi-quantitative FFQ 2 weeks before the diagnosis of GDM. GDM (n 248) was diagnosed based on the results of a 75-g, 2-h oral glucose tolerance test at 24–28 weeks gestation. We derived five different dietary patterns from a principal component analysis. The results showed that high fish–meat–eggs scores, which were positively related to protein intake and inversely related to carbohydrate intake, were associated with a higher risk of GDM (adjusted OR for quartile 4 v. quartile 1: 1·83; 95 % CI 1·21, 2·79; Ptrend=0·007) and higher plasma glucose levels. In contrast, high rice–wheat–fruits scores, which were positively related to carbohydrate intake and inversely related to protein intake, were associated with lower risk of GDM (adjusted OR for quartile 3 v. quartile 1: 0·54; 95 % CI 0·36, 0·83; Ptrend=0·010) and lower plasma glucose levels. In addition, dietary protein and carbohydrate intake significantly contributed to the associations between dietary patterns and GDM risk or glucose levels. These findings suggest that a dietary pattern characterised by high protein and low carbohydrate intake in pregnancy was associated with a higher risk of GDM, which may provide important clues for dietary guidance during pregnancy to prevent GDM.
The microstructure and oxidation behavior at high temperatures ranging from 900 °C to 1100 °C of equiatomic CrMoNbTaV high-entropy alloy produced by vacuum arc melting were investigated. The phase component, microstructure, and microhardness of the alloy were examined by using X-ray diffraction, scanning electron microscopy equipped with an energy-dispersive X-ray spectroscope, and Vickers hardness tests, respectively. The as-cast alloy consists of a single body-centered cubic (BCC) refractory metal solid solution due to the high mixing entropy effect and exhibits a dendritic microstructure. The alloy has a very high microhardness value of 923 HV due to the strong solid solution strengthening effect. The average microhardness in interdendrites (950 HV) was higher than that in dendrites (896 HV) because of composition segregation. The oxidation kinetic curves of the alloy after exposure to air at 900 and 1000 °C follow the pseudo-parabolic rate law, while the mass gain increases first and then decreases at 1100 °C. The thickness of the oxide layer increases with the increasing of oxidation time. The long rod-shaped oxidation products are composed of Nb2O5, NbO2, CrTaO4, CrNbO4, Ta9VO25, Nb9VO25, and TaO after oxidation at 900 and 1000 °C for 25 h. The oxides of CrTaO4 and CrNbO4 disappear as the oxidation temperature elevated to 1100 °C.
A key question about study abroad concerns the relative benefits and qualities of various living arrangements as sites for learning language and culture. A widely shared assumption seems to be that students choosing homestays enjoy more opportunities for engagement in high-quality interactive settings than do those who opt for residence halls. However, research on outcomes has to date produced only weak evidence for a homestay advantage, suggesting a need to understand the nature of language socialization practices in various living situations. While a number of studies have examined the nature of homestay interaction, only a few have focused on language use in residence halls or other settings where students may interact with peers who are expert second language users. Informed by a Vygotskian approach to the study of development, this article examines the specific qualities of contextualized language practices through two case studies of U.S.-based learners of Mandarin in Shanghai and their Chinese roommates. In the first case, a friendly relationship emerged from routine participation in emotionally charged conversational narrative. In the second, both participants’ interest in verbal play and humor led to enjoyment as well as profoundly intercultural dialogue. In each case, there is evidence to show that all parties enjoyed opportunities to learn. These findings suggest that residence halls can be very significant contexts for learning in study abroad settings.
Little is known about the joint mental health effects of air pollution and tobacco smoking in low- and middle-income countries.
To investigate the effects of exposure to ambient fine particulate matter pollution (PM2.5) and smoking and their combined (interactive) effects on depression.
Multilevel logistic regression analysis of baseline data of a prospective cohort study (n=41785). The 3-year average concentrations of PM2.5 were estimated using US National Aeronautics and Space Administration satellite data, and depression was diagnosed using a standardised questionnaire. Three-level logistic regression models were applied to examine the associations with depression.
The odds ratio (OR) for depression was 1.09 (95% CI 1.01–1.17) per 10 μg/m3 increase in ambient PM2.5, and the association remained after adjusting for potential confounding factors (adjusted OR = 1.10, 95% CI 1.02–1.19). Tobacco smoking (smoking status, frequency, duration and amount) was also significantly associated with depression. There appeared to be a synergistic interaction between ambient PM2.5 and smoking on depression in the additive model, but the interaction was not statistically significant in the multiplicative model.
Our study suggests that exposure to ambient PM2.5 may increase the risk of depression, and smoking may enhance this effect.
On September 22, 1985, a hard X-ray observation of Cyg X-1 was performed by using a balloon-borne CsI-NaI phoswich telescope HAPI-2 at Xianghe Balloon Facility in China. The main detector is CsI(T1) with a thickness of 0.4cm and an area of 140cm2. The energy range is 20–200KeV. The telescope reached a float altitude of about 38Km(4g/cm2). The photon's arrival time and energy loss spectrum were measured for both background and active tracking on-source observations.
Objectives: Mental arithmetic is essential to daily life. Researchers have explored the mechanisms that underlie mental arithmetic. Whether mental arithmetic fact retrieval is dependent on surface modality or knowledge format is still highly debated. Chinese individuals typically use a procedure strategy for addition; and they typically use a rote verbal strategy for multiplication. This provides a way to examine the effect of surface modality on different arithmetic operations. Methods: We used a series of neuropsychological tests (i.e., general cognitive, language processing, numerical processing, addition, and multiplication in visual and auditory conditions) for a patient who had experienced a left frontotemporal stroke. Results: The patient had language production impairment; but preserved verbal processing concerning basic numerical abilities. Moreover, the patient had preserved multiplication in the auditory presentation rather than in the visual presentation. The patient suffered from impairments in an addition task, regardless of visual or auditory presentation. Conclusions: The findings suggest that mental multiplication could be characterized as a form of modality-dependent processing, which was accessed through auditory input. The learning strategy of multiplication table recitation could shape the verbal memory of multiplication leading to persistence of the auditory module. (JINS, 2017, 23, 692–699)
Previous studies have supported the theory that there is a positive association between ferritin and carotid atherosclerosis in Western people. Diet plays an important role in determining serum ferritin concentration. Asian dietary patterns are different from Western dietary patterns, implying that there may be a difference in the association of ferritin with carotid atherosclerosis between Asian and Western people. However, few studies focus on the association between ferritin and carotid atherosclerosis among Asians. The aim of this study was to investigate how serum ferritin levels are associated with carotid atherosclerosis in an Asian adult population. A cross-sectional assessment was performed in 8302 adults in Tianjin, China. Carotid intima-media thickness (IMT) and plaques were assessed using ultrasonography, and serum ferritin was measured using the protein chip-chemiluminescence method. Multiple logistic regression analysis was used to examine the association between quartiles of serum ferritin concentration and carotid atherosclerosis. In the present study, the overall prevalence of IMT and carotid plaques in participants is 29·2 and 22·7 %, respectively. In women, after adjustments for potentially confounding factors, the OR of IMT and carotid plaques by increasing serum ferritin quartiles were 1·00, 1·39 (95 % CI 0·98–1·99), 1·39 (95 % CI 0·99–1·97), 1·81 (95 % CI 1·30–2·55) (Pfor trend<0·001) and 1·00, 1·24 (95 % CI 0·89–1·73), 1·18 (95 % CI 0·85–1·65), 1·59 (95 % CI 1·15–2·20) (Pfor trend<0·01), respectively. However, no association was found between serum ferritin and carotid atherosclerosis in men. The study demonstrated that increased serum ferritin levels are independently associated with IMT and carotid plaques in Asian women but not in Asian men.
Obesity is associated with blood pressure (BP), but the associations between different obesity indicators and BP have not reached agreement. Besides, both obesity and BP are influenced by genetic and environmental factors. Whether they share the same genetic or environmental etiology has not been fully understood. We therefore analyzed the relationship between different obesity indicators and BP components as well as the genetic and environmental contributions to these relationships in a Chinese adult twin sample. Twins aged 18–79 years (n = 941) were included in this study. Body mass index (BMI) was used as the index of general obesity, whereas waist circumference (WC), waist-to-height ratio (WHtR), and waist-to-hip ratio (WHR) were used as the indicators of central obesity. BP components included systolic blood pressure (SBP) and diastolic blood pressure (DBP). Linear regression models and bivariate structural equation models were used to examine the relation of various obesity indicators with BP components, and genetic or environmental influences on these associations, respectively. A strong association of BP components with BMI—and a somewhat weaker association with WC, WHtR, and WHR—was found in both sexes, independent of familial factors. Of these phenotypic correlations between obesity indicators and BP components, 60–76% were attributed to genetic factors, whereas 24–40% were attributed to unique environmental factors. General obesity was most strongly associated with high BP in Chinese adult twins. There were common genetic backgrounds for obesity and BP, and unique environmental factors also played a role.
Radio observational results at 232 MHz and multifrequency studies of supernova remnant (SNR) HB21 are presented in this paper. Both the integrated spectral index and the spatial variations of spectral index of the remnant were calculated by combining the new map at 232 MHz with previously published maps made at 408, 1420, 2695, and 4750 MHz.
Two transmission curved crystal spectrometers are designed to measure the hard x-ray emission in the laser fusion experiment of Compton radiography of implosion target on ShenGuang-III laser facility in China. Cylindrically curved
-quartz (10–11) crystals with curvature radii of 150 and 300 mm are used to cover spectral ranges of 10–56 and 17–100 keV, respectively. The distance between the crystal and the x-ray source can be changed over a broad distance from 200 to 1500 mm. The optical design, including the integral reflectivity of the curved crystal, the sensitivity, and the spectral resolution of the spectrometers, is discussed. We also provide mechanic design details and experimental results using a Mo anode x-ray source. High-quality spectra were obtained. We confirmed that the spectral resolution can be improved by increasing the working distance, which is the distance between the recording medium and the Rowland circle.
The aim of this study was to investigate the effect of providing supplementary Cr-enriched Bacillus subtilis (CEBS) to mice with regard to their growth performance, caecal microbiology, tissue Cr concentration, insulin receptor (IR) expression and plasma biochemical profile. A total of ninety-six Kunming strain mice were allocated to four different groups: control, CEBS, inorganic Cr and B. subtilis. After 15 d of treatment, mice that received CEBS or normal B. subtilis had higher body weights than control mice, and after 30 d mice given either CEBS or B. subtilis had greater body weights than control mice or those given inorganic Cr. The concentration of Cr in tissues (heart, liver, spleen, kidney and skeletal muscle) increased after CEBS supplementation. B. subtilis and CEBS supplementation caused a significant increase in the numbers of Lactobacillus and Bifidobacterium in the caecum, whereas the numbers of Escherichia coli and Staphylococcus decreased significantly compared with the control. The levels of IR RNA and protein in skeletal muscles increased significantly. Plasma glucose, total cholesterol, TAG and LDL-cholesterol levels declined significantly in the CEBS group compared with the control group, whereas plasma insulin and HDL-cholesterol levels increased significantly. In conclusion, CEBS supplementation enhanced the regulation of body growth, increased tissue organic Cr concentrations, altered caecal microbiota and enhanced IR expression to produce significant changes in plasma biochemistry.
The existence of black holes with masses of about one billion solar masses in quasars at redshifts z > 6 presents significant challenges to theories of the formation and growth of black holes and the black hole/galaxy co-evolution in the early Universe. Here we report a recent discovery of an ultra-luminous quasar at redshift z = 6.30, which has an observed optical and near-infrared luminosity a few times greater than those of previously known z > 6 quasars. With near-infrared spectroscopy, we obtain a black hole mass of about 12 billion solar masses, which is well consistent with the mass derived by assuming an Eddington-limited accretion. This ultra-luminous quasar with at z > 6 provides a unique laboratory to the study of the mass assembly and galaxy formation around the most massive black holes at cosmic dawn. It raises further challenges to the black hole/galaxy co-evolution in the epoch of cosmic reionization because the black hole needs to grow much faster than the host galaxy.
In this paper, a new technical scheme of high-voltage, long-pulse generator, mostly based on solid-state power devices, including magnetic pulse compressor, Blumlein-type rolled strip pulse-forming line (RSPFL) and inductive voltage adder (IVA), is proposed and investigated numerically and experimentally. The generator has potential advantages of high average power level, high repetitive rate capability, long lifetime, and long pulse achievability, which meet the requirements of military and industrial application of the pulsed power technology. Specifically, a two-stage magnetic pulse compressor was set up with iron-based amorphous cores. Total compression ratio of the device is approximately 12 and the achieved voltage efficiency is up to 92%. Low impedance, long-duration Blumlein-type RSPFL was established with characteristic impendence and electrical length of 3 Ω and 100 ns, respectively. Mylar film was selected as the solid-state dielectric. Increased by a four-stage IVA, typical quasi-square pulse was obtained with peak current of 2.3 kA and duration over 200 ns. As the resistance of the dummy load was measured to be 60 Ω, the peak voltage was approximately 138 kV. Experiments show reasonable agreement with numerical analysis.
As multifunctional electroactive materials, ferroelectric polymers are unique owing to their exceptionally high dielectric strength (>600 MV/m), high flexibility, and easy and low-temperature fabrication into required shapes. Although polyvinylidene difluoride (PVDF)-based ferroelectric polymers have been known for several decades, recent findings reveal the potential of this class of electroactive polymers (EAPs) to achieve giant electroactive responses by tuning the molecular, nano, and meso-structures. This paper presents these advances, including giant electrocaloric effect, giant electroactuation, and large, hysteresis-free polarization response. New developments in materials benefit applications, such as environmentally benign and potentially highly energy-efficient electrical field controlled solid-state refrigeration, artificial muscles, and high-energy and power density electric energy storage devices. The challenges in developing these materials to realize these applications, and strategies to further improve the responses of EAPs will be also discussed.
Protein–energy wasting (PEW) is strongly associated with high mortality in continuous ambulatory peritoneal dialysis (CAPD) patients. However, its clinical assessment has not been well defined. The aim of the present study was to investigate the relationship between combined nutritional indicators and mortality in CAPD patients. In the present retrospective cohort study, a total of 885 incident CAPD patients were enrolled. Nutritional status at the initiation of CAPD was assessed by BMI and biochemical indices (serum albumin, prealbumin, transferrin, creatinine and total cholesterol). The primary outcome was all-cause mortality. Principal components factor analysis was used to identify the combined nutritional parameters. Their association with mortality was examined by multivariable-adjusted Cox models. The mean age was 47·4 (sd 14·8) years, 59·2 % (n 524) were male and 24·6 % (n 218) were diabetic. Of the total patients, 130 (14·7 %) had BMI < 18·5 kg/m2, 439 (49·6 %) had albumin < 38 g/l ( < 3·8 g/dl), 303 (34·2 %) had prealbumin < 300 mg/l ( < 30 mg/dl), 404 (45·6 %) had transferrin < 2 g/l ( < 200 mg/dl), 501 (56·6 %) had total cholesterol < 5·2 mmol/l ( < 200 mg/dl) and 466 (52·7 %) had creatinine < 707 μmol/l ( < 8 mg/dl). Overall, three components such as visceral proteins, muscle-mass surrogate and BMI were extracted, which explained 69·95 % of the total variance of the nutritional parameters. After adjusting for demographic variables, co-morbid conditions, Hb, TAG and high-sensitivity C-reactive protein, the factor score of visceral proteins including albumin, prealbumin and transferrin was independently associated with mortality (hazard ratio 0·73, 95 % CI 0·60, 0·89; P= 0·002). Lower visceral protein concentrations may be independently associated with higher mortality in incident CAPD patients. Simultaneous measurements of serum albumin, prealbumin and transferrin could be helpful to monitor PEW.