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Two new species of free-living marine nematode discovered from an intertidal sandy beach in the Bohai Sea and from a sublittoral region in the East China Sea are described. Deontolaimus holovachovi sp. nov. is characterized by short cephalic setae (2.5–3 μm long); ventrally-unispiral amphidial fovea; excretory pore located at the level with nerve ring; lateral alae present; two pairs of lateral cervical setae present; arcuate spicules 1.5–1.6 cloacal body diameter long, with the proximal half swollen and proximal end hooked, the distal half narrow; gubernaculum with dorso-caudal apophysis; postcloacal sensilla present in males; a midventral caudal papilla with a short seta situated at posterior third of tail length. Campylaimus zhoui sp. nov. is characterized by loop-shaped amphid with very long ventral limb extending along pharyngeal region to level of anterior part of intestine, 4.7–5.2 times the length of dorsal limb; excretory pore opening posterior to the pharyngo-intestinal junction; spicules symmetrical, slightly arcuate without proximal capitulum; gubernaculum with small dorsal apophysis; precloacal supplements absent.
A Na-montmorillonite (Na-MMT) was activated with HNO3 (20 wt.%) solution at various temperatures and times to obtain acid-activated MMT (Acid-MMT). Zinc (4 wt.%) was supported on Acid-MMT via the impregnation method using Zn(NO3)2⋅6H2O as a precursor. The catalytic performance of the Zn/Acid-MMT for the aromatization of heptane was investigated. The amount and distribution of acidity of Acid-MMT, which could be adjusted by changing the acid activation time and temperature, significantly affected the heptane conversion and aromatics content. As a result, an efficient Zn/Acid-MMT catalyst for the aromatization reaction was obtained by optimizing the acid-treatment conditions of Na-MMT.
To explore if there is association between vitamin D supplementation through cod liver oil ingestion around the periconceptional period and the risk of developing severe CHD in offspring. Furthermore, we would examine the interaction between vitamin D and folic acid supplementation in the association.
A case–control study was conducted in Shanghai Children’s Medical Center, in which, a total of 262 severe CHD cases versus 262 controls were recruited through June 2016 to December 2017. All children were younger than 2 years. To reduce potential selection bias and to minimise confounding effects, propensity score matching was applied.
After propensity score matching, vitamin D supplementation seemed to be associated with decreased odds ratio of severe CHD (odds ratio = 0.666; 95% confidence intervals: 0.449–0.990) in the multivariable conditional logistic analysis. Furthermore, we found an additive interaction between vitamin D and folic acid supplementation (relative excess risk due to interaction = 0.810, 95% confidence intervals: 0.386–1.235) in the association.
The results suggested that maternal vitamin D supplementation could decrease the risk of offspring severe CHD; moreover, it could strengthen the protective effect of folic acid. The significance of this study lies in providing epidemiological evidence that vitamin D supplementation around the periconceptional period could be a potential nutritional intervention strategy to meet the challenge of increasing CHD.
More than 80% of coronavirus disease 2019 (COVID-19) cases are mild or moderate. In this study, a risk model was developed for predicting rehabilitation duration (the time from hospital admission to discharge) of the mild-moderate COVID-19 cases and was used to conduct refined risk management for different risk populations.
A total of 90 consecutive patients with mild-moderate COVID-19 were enrolled. Large-scale datasets were extracted from clinical practices. Through the multivariable linear regression analysis, the model was based on significant risk factors and was developed for predicting the rehabilitation duration of mild-moderate cases of COVID-19. To assess the local epidemic situation, risk management was conducted by weighing the risk of populations at different risk.
Ten risk factors from 44 high-dimensional clinical datasets were significantly correlated to rehabilitation duration (P < 0.05). Among these factors, 5 risk predictors were incorporated into a risk model. Individual rehabilitation durations were effectively calculated. Weighing the local epidemic situation, threshold probability was classified for low risk, intermediate risk, and high risk. Using this classification, risk management was based on a treatment flowchart tailored for clinical decision-making.
The proposed novel model is a useful tool for individualized risk management of mild-moderate COVID-19 cases, and it may readily facilitate dynamic clinical decision-making for different risk populations.
The satellite constellation with automatic dependent surveillance-broadcast on-board is of great importance for air traffic surveillance due to its multiple advantages compared with traditional methods. Although some research has been conducted on satellite constellation design based on coverage performance, the findings cannot entirely satisfy all the requirements of air traffic surveillance owing to the lack of analysis on inter-satellite links and network transmission. This paper presents a novel design of a low earth orbit satellite constellation network to solve this problem. Based on the requirements of space-based surveillance, an evaluation model of constellation performance is proposed concerning coverage, link and transmission. The simulation results show that the evaluation model can reflect the performance of a satellite constellation network designed for a space-based surveillance system, and a 55-satellite constellation design scheme with fairly good performance can fulfil the function of global real-time air traffic surveillance.
Primary liver cancer is the third leading cause of cancer-related death worldwide. Most patients are diagnosed at late stages with poor prognosis; thus, identification of modifiable risk factors for primary prevention of liver cancer is urgently needed. The well-established risk factors of liver cancer include chronic infection with hepatitis B virus (HBV) or hepatitis C virus (HCV), heavy alcohol consumption, metabolic diseases such as obesity and diabetes, and aflatoxin exposure. However, a large proportion of cancer cases worldwide cannot be explained by current known risk factors. Dietary factors have been suspected as important, but dietary aetiology of liver cancer remains poorly understood. In this review, we summarised and evaluated the observational studies of diet including single nutrients, food and food groups, as well as dietary patterns with the risk of developing liver cancer. Although there are large knowledge gaps between diet and liver cancer risk, current epidemiological evidence supports an important role of diet in liver cancer development. For example, exposure to aflatoxin, heavy alcohol drinking and possibly dairy product (not including yogurt) intake increase, while intake of coffee, fish and tea, light-to-moderate alcohol drinking and several healthy dietary patterns (e.g. Alternative Healthy Eating Index) may decrease liver cancer risk. Future studies with large sample size and accurate diet measurement are warranted and need to consider issues such as the possible aetiological heterogeneity between liver cancer subtypes, the influence of chronic HBV or HCV infection, the high-risk populations (e.g. cirrhosis) and a potential interplay with host gut microbiota or genetic variations.
Real-time and accurate fault detection and isolation is very important to ensure the reliability and precision of integrated inertial navigation and global navigation satellite systems. In this paper, the detection performance of a residual chi-square method is analysed, and on this basis an improved method of fault detection is proposed. The local test based on a standardised residual is introduced to detect and identify faulty measurements directly. Differing from the traditional method, two appropriate thresholds are selected to calculate the weight factor of each measurement, and the gain matrix is adjusted adaptively to reduce the influence of the undetected faulty measurement. The sliding window test, which uses past measurements, is also added to further improve the fault detection performance for small faults when the local test based on current measurements cannot judge whether a fault has occurred or not. Several simulations are conducted to evaluate the proposed method. The results show that the improved method has better fault detection performance than the traditional detection method, especially for small faults, and can improve the reliability and precision of the navigation system effectively.
This paper proposes a task-related electroencephalogram research framework (tEEG framework) to guide scholars’ research on EEG-based cognitive and affective studies in the context of design. The proposed tEEG framework aims to investigate design activities with loosely controlled experiments and decompose a complex design process into multiple primitive cognitive activities, corresponding to which different research hypotheses on basic design activities can be effectively formulated and tested. Thereafter, existing EEG techniques and methods can be applied to analyse EEG signals related to design. Three application examples are presented at the end of this paper to demonstrate how the proposed framework can be applied to analyse design activities. The tEEG framework is presented to guide EEG-based cognitive and affective studies in the context of design. Existing methods and models are summarized, for the effective application of the tEEG framework, from the current literature spread in a wide spectrum of resources and fields.
The dipeptide dl-methionyl-dl-methionine (Met-Met) has extremely low water solubility and better absorption than other methionine sources (such as dl-methionine and l-methionine) available in the market. Therefore, six diets (D1, D2, D3, D4, D5 and D6) containing 0, 0·07, 0·15, 0·21, 0·28 and 0·38 % Met-Met were formulated to investigate the effects of Met-Met in juvenile Nile tilapia, Oreochromis niloticus (17 g initial body weight). The results indicated that percentage weight gain and specific growth rate of fish fed with D2 and D3 diets were higher than those fed with D1, D4–D6 diets. The levels of total essential amino acid in whole body of fish fed with D3 and D4 diets were significantly higher than those fed the D1 diet. Superoxide dismutase activity and malondialdehyde content have no significant difference in fish fed the diet with or without Met-Met supplementation. Majority of reads derived from the fish intestine belonged to members of Fusobacteria, followed by Bacteroidetes and Proteobacteria. Diversity of intestinal microbiota and total antioxidant capacity in fish fed with D3 diet was significantly higher than that of other groups. Based on the growth results, the authors conclude that the optimal level of Met is 0·61 % Met with the addition of 0·15 % Met-Met for grower-phase O. niloticus.
Information collection may affect the design quality and designer's performance through changing the structure of information and the way how information is searched and organized. Based on the theoretical analysis conducted by Wang et al., the present work continues to investigate the influence of designer's natural choice of information collection strategy on his/her mental stress both theoretically and empirically. Designers’ stresses are quantified from HRV data and are compared under different information collection strategies.
Limited information is available on the prevalence and effect of hypertriglyceridaemic–waist (HTGW) phenotype on the risk of type 2 diabetes mellitus (T2DM) in rural populations.
In the present cross-sectional study, we investigated the prevalence of the HTGW phenotype and T2DM and the strength of their association among rural adults in China.
HTGW was defined as TAG >1·7 mmol/l and waist circumference (WC) ≥90 cm for males and ≥80 cm for females. Logistic regression analysis yielded adjusted odds ratios (aOR) relating risk of T2DM with HTGW.
Adults (n 12 345) aged 22·83–92·58 years were recruited from July to August of 2013 and July to August of 2014 from a rural area of Henan Province in China.
The prevalence of HTGW and T2DM was 23·71 % (males: 15·35 %; females: 28·88 %) and 11·79 % (males: 11·15 %; females: 12·18 %), respectively. After adjustment for sex, age, smoking, alcohol drinking, blood pressure, physical activity and diabetic family history, the risk of T2DM (aOR; 95 % CI) was increased with HTGW (v. normal TAG and WC: 3·23; CI 2·53, 4·13; males: 3·37; 2·30, 4·92; females: 3·41; 2·39, 4·85). The risk of T2DM with BMI≥28·0 kg/m2, simple enlarged WC and simple disorders of lipid metabolism showed an increasing tendency (aOR=1·31, 1·75 and 2·32).
The prevalence of HTGW and T2DM has reached an alarming level among rural Chinese people, and HTGW is a significant risk factor for T2DM.
Two benzodifuran (BDF) polymers, PBDF-C and PBDF-S, with alkyl and alkylthio substituted thiophene side-chains and benzodithiophene-4,8-dione (BDD) as the acceptor were designed and synthesized. Their optical, electrochemical properties and photovoltaic performances were systematically investigated. The polymer solar cells (PSCs) with a device structure of ITO/PEDOT:PSS/polymer:PC71BM/Ca/Al were fabricated. The PBDF-C based device showed a power conversion efficiency (PCE) of 3.01% after adding 1 vol% 1,8-diodooctane (DIO) as the solvent additive, and PBDF-S gave an enhanced PCE of 3.48% without any post-treatments. The enhancements were from the higher open-circuit voltage (Voc) and fill factor (FF). The thermal- and solvent-treatment-free processing is more favourable for the large area roll-to-roll manufacturing or printing technology for PSCs.
Identifying the relative importance of urban and non-urban land-use types for potential denitrification derived N2O at a regional scale is critical for quantifying the impacts of human activities on nitrous oxide (N2O) emission under changing environments. In this study we used a regional dataset from China including 197 soil samples and six land-use types to evaluate the main predictors (land use, heavy metals, soil pH, soil moisture, substrate availability, functional and broad microbial abundances) of potential denitrification using multivariate and pathway analysis. Our results provide empirical evidence that soils on farms have the greatest potential denitrifying ability (PDA) (10.92±6.08ng N2O-N·g–1 dry soil·min–1) followed by urban soil (6.80±5.35ng N2O-N·g–1 dry soil·min–1). Our models indicate that land use (low vs. high human activity), followed by total nitrogen (TN) and heavy metals (Cu, Zn, Pb, Cd) was the most important driver of PDA. In addition, our path analysis suggests that at least part of the impacts of land use on potential denitrification were mediated via microbial abundance, soil pH and substrates including TN, dissolved organic carbon and nitrate. This study identifies the main predictors of denitrification at a regional scale which is needed to quantify the impact of human activities on ecosystem functionality under changing conditions.
It has been reported that the optimal properties of materials are usually not linear to the configuration entropy of materials; in another word, the high-entropy alloys may not have the best properties among all the alloys, including medium-entropy alloys, thus all of these alloys can be universally named as entropic alloys. For entropic alloys, the design, discovery, and optimization of new materials are more complicated than conventional materials. A technique of high-throughput processing is urgently needed to improve the efficiency. In this paper, a combined method by using multitarget deposition has been proposed for parallel preparation of high-entropy to medium-entropy alloys. Films with compositional gradient were constructed in a pseudo-ternary Ti–Al–(Cr, Fe, Ni) system in this study. To facilitate the characterization of the material library, it has been divided into 144 independent units with an area of 1 cm2 and the maximum value of compositional gradient reaches ∼13 at.%/cm. The material library exhibits a high coverage of composition, and the range of element content varies from 3.3 to 89.2 at.% on average. The stability and homogeneity of the material library were analyzed from phase structure and microtopography. Preliminary screening of the phase structure and properties were performed. The phases are mainly composed of amorphous phase and body-centered cubic phase. Hardness changes nonlinearly with compositions. The material library synthesized in this study is expected to provide an effective platform for high-throughput screening of multicomponent materials.
A series of CoCrFeNiMox (x = 0.2, 0.4, 0.6, 0.8, 1.0, and 1.2) high-entropy alloys were designed to develop a eutectic high-entropy alloy system and to acquire a superfine eutectic structure. The results show that for the CoCrFeNiMox alloys, with the increase of Mo content from 0.2 to 1.2, the microstructures shift from a typical dendrite structure to a hypoeutectic microstructure (x = 0.6), and then to a fully eutectic microstructure (x = 0.8) with a lamellar spacing only 110 nm, and finally culminate in the hypereutectic structure (x = 1.0, x = 1.2). The XRD results show that CoCrFeNiMox alloys have a single FCC phase when x is 0.2 or 0.4. When Mo content is over 0.6, it begins to separate Cr9Mo21Ni20 intermetallic compounds. The hardness of the CoCrFeNiMox alloys is increasing significantly from 172.8 to 763.7 HV with the increase of Mo content. Meanwhile, the fracture strength increased but the ductility decreases. Among these alloys, the CoCrFeNiMo0.6 alloy shows excellent integrated mechanical properties of compressive fracture strength and strain, which are 2051 Mpa and 23%, respectively.
The Micro-Nano satellite TianTuo-3 (TT-3) developed by the National University of Defense Technology (NUDT) was successfully launched on 20 September 2015. The space-based Automatic Identification System (AIS) on board TT-3 works well and stably receives AIS signals from global vessels. In this work, we perform statistical analysis on the detection probability of the vessels in the concerned areas by using the TT-3 AIS data. The results suggest that the detection probability of vessels decreases as the distribution density increases, especially in the offshore areas of dense traffic and the TT3-AIS vessel detection probability in the oceans can be higher than 40%, indicating that the TT-3 AIS has achieved a high probability of coverage of vessels for a single receiving antenna. The analysis results will present helpful references both in evaluating the potential application of satellite-based AIS and for designing the next generation space-based AIS which might greatly improve the detection probability of ocean-going vessels.