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The effect of maternal folate intake on small-for-gestational-age (SGA) births remains inconclusive. The present study aimed to investigate the associations of maternal folate intake from diet and supplements with the risk of SGA births using data from a cross-sectional study in Shaanxi Province of Northwest China. A total of 7307 women who were within 12 months (median 3; 10th–90th percentile 0–7) after delivery were included. Two-level models were adopted to examine the associations of folate (dietary folate, supplemental folic acid and total folate) intake with the risk of SGA births and birth weight Z score, controlling for a minimum set of confounders that were identified in a directed acyclic graph. Results showed that a higher supplemental folic acid intake during the first trimester was negatively associated with the risk of SGA births (≤60 d v. non-use: OR 0·80; 95 % CI 0·66, 0·96; >60 d v. non-use: OR 0·78; 95 % CI 0·65, 0·94; Ptrend = 0·010; per 10-d increase: OR 0·97; 95 % CI 0·95, 0·99). A higher total folate intake during pregnancy was associated with a reduced risk of SGA births (highest tertile v. lowest tertile: OR 0·77; 95 % CI 0·64, 0·94; Ptrend = 0·010; per one-unit increase in the log-transformed value: OR 0·81; 95 % CI 0·69, 0·95). A similar pattern was observed for the birth weight Z score. Our study suggested that folic acid supplementation during the first trimester and a higher total folate intake during pregnancy were associated with a reduced risk of SGA births.
Novel NiMoO4-integrated electrode materials were successfully prepared by solvothermal method using Na2MoO4·2H2O and NiSO4·6H2O as main raw materials, water, and ethanol as solvents. The morphology, phase, and structure of the as-prepared materials were characterized by SEM, XRD, Raman, and FT-IR. The electrochemical properties of the materials in supercapacitors were investigated by cyclic voltammetry, constant current charge–discharge, and electrochemical impedance spectroscopy techniques. The effects of volume ratio of water to ethanol (W/E) in solvent on the properties of the product were studied. The results show that the pure phase monoclinic crystal NiMoO4 product can be obtained when the W/E is 2:1. The diameter and length are 0.1–0.3 µm and approximately 3 µm, respectively. As an active material for supercapacitor, the NiMoO4 nanorods material delivered a discharge specific capacitance of 672, 498, and 396 F/g at a current density of 4, 7, and 10 A/g, respectively. The discharge specific capacitance slightly decreased from 815 to 588 F/g with a retention of 72% after 1000 cycles at a current density of 1 A/g. With these superior capacitance properties, the novel NiMoO4 integrated electrode materials could be considered as promising material for supercapacitors.
Objective: Deficits in the semantic learning strategy were observed in subjects with amnestic mild cognitive impairment (aMCI) in our previous study. In the present study, we explored the contributions of executive function and brain structure changes to the decline in the semantic learning strategy in aMCI. Methods: A neuropsychological battery was used to test memory and executive function in 96 aMCI subjects and 90 age- and gender-matched healthy controls (HCs). The semantic clustering ratio on the verbal learning test was calculated to evaluate learning strategy. Medial temporal lobe atrophy (MTA) and white matter hyperintensities (WMH) were measured on MRI with the MTA and Fazekas visual rating scales, respectively. Results: Compared to HCs, aMCI subjects had poorer performance in terms of memory, executive function, and the semantic clustering ratio (P < .001). In aMCI subjects, no significant correlation between learning strategy and executive function was observed. aMCI subjects with obvious MTA demonstrated a lower semantic clustering ratio than those without MTA (P < .001). There was no significant difference in the learning strategies between subjects with high-grade WMH and subjects with low-grade WMH. Conclusion: aMCI subjects showed obvious impairment in the semantic learning strategy, which was attributable to MTA but independent of executive dysfunction and subcortical WMH. These findings need to be further validated in large cohorts with biomarkers identified using volumetric brain measurements. (JINS, 2019, 25, 706–717)
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.
This paper deals with a non-self-adjoint differential operator which is associated with a diffusion process with random jumps from the boundary. Our main result is that the algebraic multiplicity of an eigenvalue is equal to its order as a zero of the characteristic function
. This is a new criterion for determining the multiplicities of eigenvalues for concrete operators.
Dipetalonema gracile is a common parasite in squirrel monkeys (Saimiri sciureus), which can cause malnutrition and progressive wasting of the host, and lead to death in the case of massive infection. This study aimed to identify a suspected D. gracile worm from a dead squirrel monkey by means of molecular biology, and to amplify its complete mitochondrial genome by polymerase chain reaction (PCR) and sequence analysis. The results identified the worm as D. gracile, and the full length of its complete mitochondrial genome was 13,584 bp, which contained 22 tRNA genes, 12 protein-coding genes, two rRNA genes, one AT-rich region and one small non-coding region. The nucleotide composition included A (16.89%), G (20.19%), T (56.22%) and C (6.70%), among which A + T = 73.11%. The 12 protein-coding genes used TTG and ATT as start codons, and TAG and TAA as stop codons. Among the 22 tRNA genes, only trnS1AGN and trnS2UCN exhibited the TΨC-loop structure, while the other 20 tRNAs showed the TV-loop structure. The rrnL (986 bp) and rrnS (685 bp) genes were single-stranded and conserved in secondary structure. This study has enriched the mitochondrial gene database of Dipetalonema and laid a scientific basis for further study on classification, and genetic and evolutionary relationships of Dipetalonema nematodes.
The effect of Cu addition varied from 0 to 4 mass% on the corrosion resistance and electrochemical response in Ni–Co–Cr–Mo alloys was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy, and Mott–Schottky analysis. Results indicate that the Ni–Co–Cr–Mo alloy with 2 mass% Cu exhibited the most superior corrosion resistance, and the presence of Cu greatly influenced the outer porous layer. The Ni–Co–Cr–Mo alloys’ corrosion resistance was not simply increasing with copper addition increasing from 0 to 4 mass%. The X-ray photoelectron spectroscopy etching analysis was also conducted to illustrate the fraction of Cu at various depths in the passive film, and the results reveal that a maximum limit on Cu content (appropriately 3.10 mass%) existed in the outermost surface in the present condition. Among the studied alloys, the Ni–Co–Cr–Mo–2%Cu alloy formed the thickest passive film with the lowest donor density.
The purpose of this study was to investigate whether hesitant or preoccupied people (state-oriented) have different goal content and motives compared to initiative or disengaged people (action-oriented). People rated the degree of autonomous versus controlled feelings for extrinsic or intrinsic types of goals. Results showed that action-oriented people had a higher autonomous motive than state-oriented people for intrinsic goals, but not for extrinsic goals. Moreover, action-oriented individuals were related to a more internalised goal content (intrinsic goal) than state-oriented individuals. Implications for goal internalisation are discussed.
To investigate the prevalence of canine and feline hookworms in South China, and to assess the risk of zoonotic hookworms to humans, one pair of primers (HRM-F/HRM-R) was designed to establish a high-resolution melting (HRM) method based on internal transcribed spacer 1 (ITS-1) rDNA for the detection of Ancylostoma ceylanicum, A. caninum and A. tubaeforme infection. The results showed that the HRM for the three hookworms produced different melting-curve profiles, where melting temperature (Tm) values were 84.50°C for A. ceylanicum, 82.25°C for A. caninum and 81.73°C for A. tubaeforme, respectively. The reproducibility of intra- and inter-assay melting curves was almost perfect. The lowest concentration detected was about 5.69 ×10−4 g/μl. The HRM detection results from 18 canine and feline hookworm samples were in complete accordance with their sequencing results. The HRM method was more sensitive than the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) technique in the detection of 98 clinical samples. It is concluded that the HRM method can differentiate between A. ceylanicum, A. caninum, A. tubaeforme and their mixed infections, which may provide important technical support for the zoonotic risk assessment and molecular epidemiological survey of canine and feline hookworms.
The lichen family Ophioparmaceae contains three genera: Boreoplaca, Hypocenomyce and Ophioparma. The genus Hypocenomyce is reported here for the first time for China, being represented by the species Hypocenomyce scalaris which is distributed in south-western China. For the genus Ophioparma, one new species is described in this paper, namely Ophioparma pruinosa Li S. Wang & Y. Y. Zhang sp. nov., which is characterized by a pruinose thallus and the presence of usnic acid. Ophioparma araucariae is also reported as new for the Chinese lichen biota. Previous reports of O. lapponica in China are recognized as misidentifications of O. ventosa. Descriptions, keys and phylograms are provided for these species.
In this paper, we give the definition of tree-indexed Markov chains in random environment with countable state space, and then study the realization of Markov chain indexed by a tree in random environment. Finally, we prove the strong law of large numbers and Shannon–McMillan theorem for Markov chains indexed by a Cayley tree in a Markovian environment with countable state space.
Children’s poor growth and nutrition status has serious consequences and therefore it is important to understand its contributing factors.
A community-based interventional study focusing on child feeding was conducted in a rural community in China. Data from the intervention group at baseline (1–4 months of age) and follow-up visits (12 and 18 months of age) were used in the present study (n 236). A structural equation model was generated to explore the effects of family wealth, household food safety, dietary intake, diseases and other factors on the growth and nutrition of young children.
Mother’s knowledge and behaviours on household food safety had positive effects on children’s weight-for-age Z-score (WAZ; βdirect=0·03 and 0·15, respectively, at 12 months of age; βdirect=0·02 and 0·08, respectively, at 18 months; P<0·05) and weight-for-length Z-score (WLZ; βdirect=0·04 and 0·21, respectively, at 12 months of age; βdirect=0·01 and 0·06, respectively, at 18 months; P<0·05). While mothers’ feeding behaviours and children’s dietary intake at 12 months of age were positively associated with WAZ and/or WLZ at current and later ages, children’s diseases were negatively associated with WAZ and WLZ cross-sectionally.
Caregiver’s knowledge and feeding behaviours, and children’s dietary intake and diseases, are factors influencing the WAZ and WLZ of children. Promoting feeding and health knowledge and behaviours at early stages of childhood can improve children’s physical growth at later ages.
A new band-reject frequency-selective surface (FSS) based on dual-band near-zero refractive index metamaterial (ZIM) design is presented in this paper. Consisting of a planar array of complementary dual-layer symmetry resonant ring, the proposed FSS exhibits a high-selective band-reject filtering response. From the viewpoint of effective medium, the subwavelength FSS is characterized by near-zero effective magnetic permeability and near-zero effective electric permittivity in two different operational bands, respectively. The corresponding resonant behavior and E-field distributions are analyzed in detail. A prototype of the proposed FSS working in X-band is fabricated and measured. The simulation and experiment results verify the effectiveness and correctness of the ZIM-based design method.
This paper deals with the spectral properties of self-adjoint Schrödinger operators with δʹ-type conditions on infinite regular trees. Firstly, we discuss the semi-boundedness and self-adjointness of this kind of Schrödinger operator. Secondly, by using the form approach, we give the necessary and sufficient condition that ensures that the spectra of the self-adjoint Schrödinger operators with δʹ-type conditions are discrete.
To study the clinical effect of lens cleaning paper patching on traumatic eardrum perforations.
A total of 122 patients were divided into 2 groups, of which 56 patients were treated with lens cleaning paper patching and 66 acted as controls. The closure rate and healing time were compared between the two groups.
The healing rate of small perforations was 96.4 per cent (27 out of 28) in the patching group and 90 per cent (27 out of 30) in the control group. The difference was not statistically significant (p > 0.05). The healing rate of large perforations was 89.3 per cent (25 out of 28) and 80.6 per cent (29 out of 36) in the two groups, respectively. The difference was statistically significant (p < 0.05). The healing time of large perforations was shorter in the patching group than in the control group (p < 0.01).
Patching with lens cleaning paper under an endoscope can accelerate the closure of large traumatic eardrum perforations.
Leucine plays an important role in promoting muscle protein synthesis and muscle remodelling. However, what percentage of leucine is appropriate in creep feed and what proteome profile alterations are caused by dietary leucine in the skeletal muscle of piglets remain elusive. In this case, we applied isobaric tags for relative and absolute quantitation to analyse the proteome profile of the longissimus dorsi muscles of weanling piglets fed a normal leucine diet (NL; 1·66 % leucine) and a high-leucine diet (HL; 2·1 % leucine). We identified 157 differentially expressed proteins between these two groups. Bioinformatics analysis of these proteins exhibited the suppression of oxidative phosphorylation and fatty acid β-oxidation, as well as the activation of glycolysis, in the HL group. For further confirmation, we identified that SDHB, ATP5F1, ACADM and HADHB were significantly down-regulated (P<0·01, except ATP5F1, P<0·05), whereas the glycolytic enzyme pyruvate kinase was significantly up-regulated (P<0·05) in the HL group. We also show that enhanced muscle protein synthesis and the transition from slow-to-fast fibres are altered by leucine. Together, these results indicate that leucine may alter energy metabolism and promote slow-to-fast transitions in the skeletal muscle of weanling piglets.
A well-preserved fossil priapulid worm, Xiaoheiqingella sp., is reported from the early Cambrian Guanshan Lagerstätte (Cambrian Series II, Stage 4) near Kunming City, Yunnan Province, SW China. The body of the animal consists of four sections: a swollen introvert, a constricted neck, a finely annulated trunk and a caudal appendage. The body configuration exhibits a close resemblance to that of the crown group priapulid Xiaoheiqingella peculiaris from the early Cambrian Chengjiang Lagerstätte. The new discovery provides another striking example of crown group priapulids, representing the third occurrence of crown group fossil priapulids after the Chengjiang Lagerstätte (Cambrian Series II, Stage 3) and the Mazon Creek Lagerstätte (late Moscovian Stage, Pennsylvanian). The discovery also sheds new light on the early diversity and evolution of priapulid worms.
Ancylostoma tubaeforme may infect canids, felids and humans, and pose a potential risk to public health. Polymerase chain reaction (PCR) techniques were used to amplify the complete mitochondrial (mt) genome sequence of A. tubaeforme from cats and to analyse its sequence characteristics after molecular identification based on the internal transcribed spacer ITS1+ sequence. The results show that the complete mt genome sequence (GenBank accession number KY070315) of A. tubaeforme from cats was 13,730 bp in length, including 12 protein-coding genes, 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes, two non-coding regions and an AT-rich region. The nucleotide content of A and T was 77.93%, biased toward A and T. Twelve protein-coding genes used ATT, TTG and GTG as initiation codons, and TAA, TAG, TA and T as termination codons. The length of the 22 tRNA genes ranged from 52 to 62 bp, their predicted secondary structures were D loops and V loops. The lengths of the two rRNAs were 958 and 697 bp. Phylogenetic analyses showed that A. tubaeforme from cats was in the lineage of Ancylostoma, having a close phylogenetic relationship with A. caninum. This study reports for the first time the mt genome of A. tubaeforme from cats in China, which could enhance the mt genome database of Ancylostomatidae nematodes, and it offers the scientific basis for further studies in the genetic diversity of hookworms among different hosts.
In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed. On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection (MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.
The morphology, chemistry and phylogenetic relationships of Chinese populations
of Bulbothrix are described. Nine species, including two new
species B. mammillaria Y. Y. Zhang & Li S. Wang sp.
nov. and B. lacinia Y. Y. Zhang & Li S. Wang sp.
nov., and two newly recorded for the flora, B. scortella and
B. meizospora, are reported. Bulbothrix
mammillaria can be recognized by the sparse cilia that are reduced to a
bulbate structure and the broad lobes (3–11 mm). Bulbothrix
lacinia differs from other species of the genus by dark brown,
spherical to short-cylindrical isidia and common lacinulae on the upper surface.
Phylogenetic relationships of currently known ITS sequences from
Bulbothrix were inferred to assess the affinities of the
new species. A key to all known species from China is presented.