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There is still controversy about optimal dietary iodine intake as the Universal Salt Iodization policy enforcement in China. A modified iodine balance study was thus conducted to explore the suitable iodine intake in Chinese adult males using the iodine overflow hypothesis. In this study, thirty-eight apparently healthy males (19·1 (sd 0·6) years) were recruited and provided with designed diets. After the 14-d iodine depletion, daily iodine intake gradually increased in the 30-d iodine supplementation, consisting of six stages and each of 5 d. All foods and excreta (urine, faeces) were collected to examine daily iodine intake, iodine excretion and the changes of iodine increment in relation to those values at stage 1. The dose–response associations of iodine intake increment with excretion increment were fitted by the mixed effects models, as well as with retention increment. Daily iodine intake and excretion were 16·3 and 54·3 μg/d at stage 1, and iodine intake increment increased from 11·2 μg/d at stage 2 to 118·0 μg/d at stage 6, while excretion increment elevated from 21·5 to 95·0 μg/d. A zero iodine balance was dynamically achieved as 48·0 μg/d of iodine intake. The estimated average requirement and recommended nutrient intake were severally 48·0 and 67·2 μg/d, which could be corresponded to a daily iodine intake of 0·74 and 1·04 μg/kg per d. The results of our study indicate that roughly half of current iodine intakes recommendation could be enough in Chinese adult males, which would be beneficial for the revision of dietary reference intakes.
Widely distributed Mid-Neoproterozoic mafic rocks of the Qilian – Qaidam – East Kunlun region record the tectonic evolution of the northeastern Tibetan Plateau. This study presents whole-rock geochemistry, zircon U–Pb geochronology and Hf isotopes for the Xialanuoer gabbros of the central South Qilian Belt (SQB). Zircon laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS) U–Pb dating indicates that the gabbros were emplaced at ca. 738 Ma, indicating they are contemporaneous with mafic magmatism elsewhere in the northeastern Tibetan Plateau. The gabbros have low SiO2, Cr and Ni contents and Mg# values, are relatively enriched in light rare-earth elements (LREEs) and depleted in high-field-strength elements (HFSEs; e.g. Nb and Ta), have no positive Zr or Hf anomalies and have relatively high Nb/Ta but low Nb/La ratios. These data indicate that the Xialanuoer gabbros formed from calc-alkaline basaltic magmas that were originally generated by the partial melting of an enriched mantle of type-I (EMI-type) enriched region of the lithospheric mantle, underwent little to no crustal contamination prior to their emplacement, and have within-plate basalt geochemical affinities. Combining these data with the presence of widespread contemporaneous continental rift-related magmatism and sedimentation in the North Qilian, Central Qilian, South Qilian, Quanji, North Qaidam and East Kunlun regions suggests that the northeastern Tibetan Plateau underwent Mid-Neoproterozoic continental rifting, which also affected other Rodinian blocks (e.g. Tarim, South China, Australia, North America and Southern Africa).
The extinct family Hylicellidae, as the ancestral group of modern cicadomorphans, had a wide distribution and a very high species-level biodiversity from the Triassic to Early Cretaceous. We herein report 11 new hylicellid specimens from the Jurassic Daohugou beds of Inner Mongolia, NE China, and execute geometric morphometric analysis (GMA) to elucidate their systematic position. Our GMA and subsequent morphometric statistics indicate that 10 of our new specimens can be compared to the holotype of Cycloscytina gobiensis, and one is new to science. Cycloscytina incompleta new species is erected based on this specimen, with the following discriminatory tegminal traits: C3 almost as long as and slightly narrower than C2, and the forking position of stem M distinctly migrates towards wing apex and much apicad of the stem CuA bifurcating. Additionally, Cycloscytina plachutai is herein transferred to the procercopid genus Procercopina, resulting in P. plachutai new combination. To date, just a few body structures of Hylicellidae have been revealed, and the new whole-bodied hylicellids reported herein provide some novel insights on the evolution of basal Clypeata. This study also emphasizes the use of morphometric analysis in the systematics of wing-bearing insects such as hylicellids.
Routine coronavirus disease 2019 (COVID-19) screening found 1 asymptomatic COVID-19 patient. An emergency sampling team was organized consisting of 1200 health-care workers, and a total of 3.2228 million COVID-19 samples had been collected and detected. This study summarizes the on-site management experience in large-scale COVID-19 nucleic acid testing from various aspects: staff preparation, materials preparation, site layout, logistics support, and information system support. Suggestions are put forward for the deficiencies and parts needing improvement. Such deficiencies included some sampling sites were not properly chosen, different areas were unclearly marked off from each other, and some site moving lines were confounding; how to communicate with the street service workers who had little professional knowledge on the epidemic spread or the working principles of the workflow and site layout; and the way to resolve conflicts on site.
The significance of spiritual care competence among nurses has been emphasized across countries and cultures in many studies. However, there were few studies on correlations among spiritual care competence, spiritual care perceptions, and spiritual health of nurses in China.
Objective
To investigate spiritual care competence, spiritual care perceptions, and spiritual health, and examine the correlations among spiritual care competence, spiritual care perceptions and spiritual health, and the mediating role of spiritual health between other two variables of Chinese nurses.
Methods
A cross-sectional and correlational design was implemented, and the STROBE Checklist was used to report the study. A convenience sample of 2,181 nurses were selected from 17 hospitals in 3 provinces, China. Participants provided data on sociodemographic by completing the Chinese Version of the Spiritual Care Competence Scale, the Chinese Version of the Spiritual Care-Giving Scale, and the Spiritual Health Scale Short Form. Descriptive statistics, univariate, multiple linear regression, and Pearson correlation analysis were used to analyze data.
Results
The total scores of spiritual care competence, spiritual care perceptions, and spiritual health were 58.25 ± 16.21, 144.49 ± 16.87, and 84.88 ± 10.57, respectively, which both were moderate. Spiritual care competence was positively correlated with spiritual care perceptions (r = 0.653, p < 0.01) and spiritual health (r = 0.587, p < 0.01). And spiritual health played a mediating role between the other two variables (accounting for 35.6%).
Significance of results
The spiritual care competence, spiritual care perceptions, and spiritual health of Chinese nurses need to be improved. It is recommended that nursing managers should pay attention to spiritual care education of nurses, and improve spiritual care perceptions and spiritual health in multiple ways, so as to improve their spiritual care competence and to maximize the satisfy spiritual care needs of patients in China.
A compact four-element ultra-wideband (UWB) multiple-input–multiple-output (MIMO) antenna with dual polarization and dual-notched capabilities was developed and fabricated. The MIMO antenna is composed of four orthogonally placed half-cutting UWB antenna elements. This orthogonal placement improves the isolation. Furthermore, an L-shaped slot and a continuous bending slot are etched to realize the band-rejection function in the WiMAX and WLAN bands. The result shows that the antenna achieved operating bands of 2.9–16.5 GHz (140.2%, S11 < −10 dB), fully covering the UWB (3.1–10.6 GHz). The port isolation is greater than 23 dB in the frequency band of interest, excluding two rejected bands. Moreover, the MIMO antenna has excellent diversity performance, such as a low envelope correlation coefficient (<0.004), high diversity gain (approximately 10 dB), and good omnidirectional radiation characteristics.
A single-layer ultra-wideband (UWB) stop-band frequency selective surface (FSS) has several advantages in wireless systems, including a simple design, low debugging complexity, and an appropriate thickness. This study proposes a miniaturized UWB stop-band FSS design. The proposed FSS structure consists of a square-loop and metalized vias that are arranged on a single layer substrate; it has an excellent angle and polarization-independent characteristics. At an incident angle of 60°, the polarization response frequencies of the transverse electric and magnetic modes only shifted by 0.003 f0 and 0.007 f0, respectively. The equivalent circuit models of the square-loop and metallized vias structure are analysed and the accuracy of the calculation is evaluated by comparing the electromagnetic simulation. The 20 × 20 array constitutes an FSS reflector with a unit size of 4.2 mm × 4.2 mm (less than one-twentieth of the wavelength of 3 GHz), which realizes an UWB quasi-constant gain enhancement (in-band flatness is <0.5 dB). Finally, the simulation results were verified through sample processing and measurement; consistent results were obtained. The FSS miniaturization design method proposed in this study could be applied to the design of passband FSS (complementary structure), antennas and filters, among other applications.
The present study explores whether embodied meaning is activated in comprehension of action-related Mandarin counterfactual sentences. Participants listened to action-related Mandarin factual or counterfactual sentences describing transfer events (actions towards or away from the participant), and then performed verb-compatible or -incompatible motor action after a transfer verb (action towards or away from the participant) onset. The results demonstrated that motor simulation, specifically the interfering action-sentence compatibility effect (ACE), was obtained in both factual and counterfactual sentences. Additionally, the temporal course of motor resonance was slightly different between factual and counterfactual sentences. We concluded that embodied meaning was activated in action-related Chinese counterfactual sentences. The results supported a neural network model of Chersi, Thill, Ziemke, and Borghi (2010), proposed within the embodiment approach, which explains the interaction between processing action-related sentences and motor performance. Moreover, we speculated that the neural network model of Chersi et al. was also applicable to action-related Mandarin counterfactual comprehension.
A compact reconfigurable filtering ultra-wideband (UWB) antenna with switchable band-notched functions is proposed. The basic structure of the proposed design is a filtering slot antenna with good band-edge selectivity using stepped impedance resonator feeding line. The reconfigurability is achieved by using two microstrip lines paralleling to the feeding line and two PIN diodes. The reconfigurable structure and bias circuit of the antenna are relatively simple and are not connected to the radiation structure, so they have little negative influence on the radiation characteristics of the antenna. Total four states could be achieved by using two PIN diodes to short the microstrip lines and ground. To verify the performance of the final design, multiple measured and simulated results in frequency and time domain are studied and analyzed. The measured results agreed very well with simulation. Compared with the traditional UWB antenna, the proposed antenna has advantages in size, filtering function in-band and out-of-band, and tunable states for multiple UWB applications.
In this paper, the design of a graded honeycomb radar absorbing structure (RAS) is presented to realize both a wide bandwidth and absorption over a wide range of angles. For both transverse-electric and transverse-magnetic polarization, a fractional bandwidth of more than 118.6% is achieved for at least a 10 dB reflectivity reduction when the incident angle is <45°, an 8 dB reduction when the incident angle is <55° and a 5 dB reduction when the incident angle is <70°. Meanwhile the 10 dB reduction upper angle limit is approximately 30° for the uniform coating honeycomb RAS in the literature, which loses its absorbing ability when the incident angle is larger than 55°. Furthermore, the total thickness of our design is 10.7 mm, which is only approximately 1.29 times that of the theoretical limitation. The good agreement between the calculated, simulated, and measured results demonstrates the validity of this optimization.
A compact printed reconfigurable monopole antenna with switchable band-notches is designed and manufactured. The proposed antenna mainly consists of a disc-like radiator with two pairs of T-shaped strips protruded inside a rectangular aperture. Five PIN diode switches are employed to bridge or open the slots, which allow the antenna to be configured into three different structures functioning as an ultra-wideband (UWB) antenna, or an antenna with notched frequencies at WLAN or WiMAX band. Design and optimization of the antenna are done using CST Microwave Studio. After fabrication on an FR4 substrate with dimensions of 35 mm (width) × 41 mm (length) × 1.5 mm (thickness), numerical and experimental results of the proposed reconfigurable antenna are presented and discussed. The experimental results confirm the design as a good candidate for UWB applications.
The Sinoalidae, as one of the three Mesozoic froghopper families, was recently recognized from the latest Middle–earliest Late Jurassic Daohugou Biota of northeastern China. We herein report some new materials from the same horizon and locality, providing some new insights on morphological diversity and evolution of this family. Shufania hani new genus new species indicates that the relative branching position of veins M and CuA of the forewing is highly variable within the Sinoalidae and not appropriate for family-level diagnosis. The venations of three reported sinoalid hind wings are conservative, likely due to its simplified topology and reduced terminal branches. Color patterns of hind wings are likely variable for different sinoalid froghoppers. However, considering that color pattern is easily weakened or even erased by diagenetic processes for imprint fossils, the morphological character is not reliable for distinguishing different sinoalid taxa. Additionally, our new material suggests that the number of lateral spines of the hind tibia can vary intra-individually for sinoalids, just as in some recent froghoppers.
X-ray powder diffraction data, unit-cell parameters, and space group for beta-methyl vinyl phosphate (MAP), C29H27N2O10P, are reported [a = 17.293(4) Å, b = 6.142(6) Å, c = 14.464(8) Å, α = γ = 90°, β = 112.048(0)°, unit-cell volume V = 1424.19 Å3, Z = 2, and space group P21]. All measured lines were indexed and are consistent with the P21 space group. No detectable impurity was observed.
Nanobiosensors have drawn significant research interest in recent years owing to the advantages of label-free, electrical detection. However, nanobiosensors fabricated by bottom-up process are limited in terms of yield and device uniformity due to the challenges in assembly. Nanobiosensors fabricated by top-down process, on the other hand, exhibit better uniformity but require time and costly processes and materials to achieve the critical dimensions required for high sensitivity. In this report, we introduce a top-down nanobiosensor based on polysilicon nanoribbon. The polysilicon nanoribbon devices can be fabricated by conventional photolithography with only materials and equipments used in the standard CMOS process, thus resulting in great time and cost efficiency, as well as scalability. The devices show great response to pH changes with a wide dynamic range and high sensitivity. Biomarker detection is also demonstrated with clinically relevant sensitivity. Such results suggest that polysilicon nanoribbon devices exhibit great potential toward a highly efficient, reliable and sensitive biosensing platform.
We present reflection and refraction of a global EUV wave observed by SDO on August 4, 2011. The global EUV wave originated in the NOAA AR 11261 located at the solar northwest. Partial EUV wave stopped and partial EUV wave traversed through the active region 11263 during the propagation of the EUV wave. Partial EUV wave interacted with coronal hole and was reflected and refracted by coronal hole.
Two flares occurred simultaneously in active region NOAA 9433 on 2001 April 25. The GOES X-ray fluxes show only one peak during the two flares. The negative magnetic polarities in the two flaring regions exhibited a clockwise rotation motion around the positive polarities, which can be seen from the evolution of the SOHO/MDI magnetograms. Through analyzing the potential fields extrapolated from the MDI magnetogram, we find that there is a channel strode by a group of magnetic field lines connecting the two flaring regions.
Our previous study showed that Erythrina variegata L. (EV) inhibited bone loss and improved bone properties in ovariectomised rats. The purpose of the present study is to investigate the potential mechanism involved in mediating the osteoprotective actions of EV. Female Sprague–Dawley rats were fed a phyto-oestrogen-free diet and subjected to either ovariectomy or a sham operation. Ovariectomised rats were treated with genistein (40 mg/kg) as well as low (200 mg/kg), medium (500 mg/kg) or high (1000 mg/kg) doses of EV extract. Bone properties and mRNA expressions were evaluated by micro-computed tomography and quantitative RT-PCR, respectively. Osteoclast differentiation in RAW 264·7 cells was studied by tartrate-resistant acid phosphatase (TRAP) staining. High doses of EV could decrease urinary Ca and P excretion, maintain serum Ca and P level, and exert beneficial effects on the micro-structure and morphology of trabecular bone and cortical bone in ovariectomised rats. EV suppressed the up-regulation of cathepsin K mRNA and the down-regulation of osteoprotegrin mRNA in the tibia of ovariectomised rats. TRAP-positive cell numbers were significantly decreased in receptor activator of nuclear factor-κB ligand (RANKL)-induced RAW 264·7 cells when co-cultured with EV extracts. The present study indicated that the protective effects of EV on bone properties in ovariectomised rats are likely to be mediated by its inhibitory actions on the process of bone resorption via the suppression of osteoclast differentiation and maturation.
The aims of the present paper were to assess the nutritional status of children under 5 years old using the 2006 WHO Child Growth Standards (‘the WHO standards’) and to compare the results with those obtained using the National Center for Health Statistics/WHO international growth reference (‘the NCHS reference’).
Design
This was a community-based cross-sectional survey. The WHO standards were used to calculate Z-scores of height-for-age (HAZ), weight-for-age (WAZ), weight-for-height (WHZ) and BMI-for-age (BMIZ).
Setting
Fifty counties of thirteen mid-western provinces, China.
Subjects
A total 8041 children aged <5 years were measured during a 2-month period from August to October 2006.
Results
The prevalence of stunting, underweight and wasting were 30·2 %, 10·2 % and 2·9 %, respectively. The prevalence of overweight and the possible risk of overweight were as high as 4·1 % and 16·8 %. Further analysis among the children with possible risk of overweight found that the percentage of stunting (HAZ < −2) was 57·6 %, the percentage with −2 ≤ HAZ ≤ 2 was 41·0 % and the percentage with HAZ > 2 was only 1·4 %. The prevalence of stunting was 21·9 % and of underweight was 12·7 % by the NCHS reference.
Conclusions
Stunting was the most serious problem that was impeding child growth and development. The high rate of ‘overweight’ was a false impression, the truth being ‘stunting overweight’, and the way to solve it should be to increase protein and other nutrients in the diet at an early age.