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Shifts in the maternal gut microbiota have been implicated in the development of gestational diabetes mellitus (GDM). Understanding the interaction between gut microbiota and host glucose metabolism will provide a new target of prediction and treatment. In this nested case-control study, we aimed to investigate the causal effects of gut microbiota from GDM patients on the glucose metabolism of germ-free (GF) mice. Stool and peripheral blood samples, as well as clinical information, were collected from 45 GDM patients and 45 healthy controls (matched by age and prepregnancy body mass index (BMI)) in the first and second trimester. Gut microbiota profiles were explored by next-generation sequencing of the 16S rRNA gene, and inflammatory factors in peripheral blood were analyzed by enzyme-linked immunosorbent assay. Fecal samples from GDM and non-GDM donors were transferred to GF mice. The gut microbiota of women with GDM showed reduced richness, specifically decreased Bacteroides and Akkermansia, as well as increased Faecalibacterium. The relative abundance of Akkermansia was negatively associated with blood glucose levels, and the relative abundance of Faecalibacterium was positively related to inflammatory factor concentrations. The transfer of fecal microbiota from GDM and non-GDM donors to GF mice resulted in different gut microbiota colonization patterns, and hyperglycemia was induced in mice that received GDM donor microbiota. These results suggested that the shifting pattern of gut microbiota in GDM patients contributed to disease pathogenesis.
This study aimed to identify clinical features for prognosing mortality risk using machine-learning methods in patients with coronavirus disease 2019 (COVID-19). A retrospective study of the inpatients with COVID-19 admitted from 15 January to 15 March 2020 in Wuhan is reported. The data of symptoms, comorbidity, demographic, vital sign, CT scans results and laboratory test results on admission were collected. Machine-learning methods (Random Forest and XGboost) were used to rank clinical features for mortality risk. Multivariate logistic regression models were applied to identify clinical features with statistical significance. The predictors of mortality were lactate dehydrogenase (LDH), C-reactive protein (CRP) and age based on 500 bootstrapped samples. A multivariate logistic regression model was formed to predict mortality 292 in-sample patients with area under the receiver operating characteristics (AUROC) of 0.9521, which was better than CURB-65 (AUROC of 0.8501) and the machine-learning-based model (AUROC of 0.4530). An out-sample data set of 13 patients was further tested to show our model (AUROC of 0.6061) was also better than CURB-65 (AUROC of 0.4608) and the machine-learning-based model (AUROC of 0.2292). LDH, CRP and age can be used to identify severe patients with COVID-19 on hospital admission.
Precise positioning with low-cost single-frequency global navigation satellite system (GNSS) receivers has great potential in a wide range of applications because of its low price and improved accuracy. However, challenges remain in achieving reliable and accurate solutions using low-cost receivers. For instance, the successful ambiguity fixing rate could be low for real-time kinematic (RTK) while large errors may occur in precise point positioning (PPP) in some scenarios (e.g., trees along the road). To solve the problems, this paper proposes a method with the aid of additional lane-level digital map information to improve the accuracy and reliability of RTK and PPP solutions. In the method, a digital camera will be applied for lane recognition and the positioning solution from a low-cost receiver will be projected to the digital map lane link. With the projected point position as a constraint, the RTK ambiguity fixing rate and PPP performance can be enhanced. A field kinematic test was conducted to verify the improvement of the RTK and PPP solutions with the aid of map matching. The results show that the RTK ambiguity fixing rate can be increased and the PPP positioning error can be reduced by map matching.
This paper claims that palliative care (PC) is a suitable approach for offering comprehensive support to patients with life-threatening illness and unavoidable asthenia, to enhance their quality of life in aging and chronic illness. There are however some conceptual barriers to accessing that care on the Chinese Mainland: (1) Death-denying culture and society; (2) Misguidance and malpractice derived from the biomedical model; (3) Prejudice against PC and certain deviant understandings of filial piety culture. To counter these obstacles, the study introduces the philosophy of Chinese Taoist Chuang-tze to enlighten the public from ignorance and remove some illusions about death and dying; inspire people to face and accept illness and death calmly, and keep harmony and inner peace of mind to alleviate suffering, with the aim of providing wisdom and a shift of attitude toward life and death. Chuang-tze’s thoughts are consistent with the provision of palliative care, and to a certain degree, can promote its acceptability and delivery, and the conception of good death in practice.
Findings for the roles of dairy products, Ca and vitamin D on ovarian cancer risk remain controversial. We aimed to assess these associations by using an updated meta-analysis. Five electronic databases (e.g. PubMed and Embase) were searched from inception to 24 December 2019. Pooled relative risks (RR) with 95 % CI were calculated. A total of twenty-nine case–control or cohort studies were included. For comparisons of the highest v. lowest intakes, higher whole milk intake was associated with increased ovarian cancer risk (RR 1·35; 95 % CI 1·15, 1·59), whereas decreased risks were observed for higher intakes of low-fat milk (RR 0·84; 95 % CI 0·73, 0·96), dietary Ca (RR 0·71; 95 % CI 0·60, 0·84) and dietary vitamin D (RR 0·80; 95 % CI 0·67, 0·95). Additionally, for every 100 g/d increment, increased ovarian cancer risks were found for total dairy products (RR 1·03; 95 % CI 1·01, 1·04) and for whole milk (RR 1·07; 95 % CI 1·03, 1·11); however, decreased risks were found for 100 g/d increased intakes of low-fat milk (RR 0·95; 95 % CI 0·91, 0·99), cheese (RR 0·87; 95 % CI 0·76, 0·98), dietary Ca (RR 0·96; 95 % CI 0·95, 0·98), total Ca (RR 0·98; 95 % CI 0·97, 0·99), dietary vitamin D (RR 0·92; 95 % CI 0·87, 0·97) and increased levels of circulating vitamin D (RR 0·84; 95 % CI 0·72, 0·97). These results show that whole milk intake might contribute to a higher ovarian cancer risk, whereas low-fat milk, dietary Ca and dietary vitamin D might reduce the risk.
Aeolian dust deposits from continent and ocean have been extensively investigated to reflect past changes in source aridity and atmospheric circulations. Aeolian flux (AF) as a quantitative dust proxy has been widely used in both palaeoenvironmental reconstruction and numerical simulation. However, available AF data on the Chinese Loess Plateau (CLP) is too limited to assess the temporal–spatial variations at glacial–interglacial timescales, and therefore cannot be used as robust input parameters in palaeoclimate models. Here we investigate eight loess profiles along two N–S-aligned transects on the CLP to quantitatively estimate the AF variations over the last glacial–interglacial cycle. We first establish a refined chronological framework based on optically stimulated luminescence chronology and pedostratigraphic correlation. AF was then estimated by multiplying the sedimentation rate and bulk density. The results show that the AF increases from 2–18 g cm−2 ka−1 in the southeastern CLP to 14–105 g cm−2 ka−1 in the northwestern CLP. At glacial–interglacial scales, the AF varies from 2–20 g cm−2 ka−1 during the last interglacial to 8–105 g cm−2 ka−1 in the last glaciation. Due to more spatial coverage and better age constraints, our AF data can be used to refine other AF datasets and to improve the proxy–model comparison.
We have designed and developed the digital correlation receiver for Mingantu Spectral Radioheliograph (MUSER). The MUSER digital correlation receiver is implemented to sample, channelise, and correlate a 400 MHz wide solar radio signal of 40-antenna output from MUSER intermediate-frequency array and 60-antenna output from MUSER high-frequency array. The polyphase filter channeliser is used for wide-band channelisation and proved to be efficient to realise narrow-band filtering (
MHz) in a high-speed digital signal-processing pipeline (sampling rate
Gsps). All modules of the digital correlation receiver are implemented on FPGA-based hardware and integrated via high-speed backplane, which makes a well-performed and economical correlator system for MUSER array. The future upgrade is also addressed including spectral resolution enhancement and radio-frequency-interference excision.
Maternal supraphysiological estradiol (E2) environment during pregnancy leads to adverse perinatal outcomes. However, the influence of oocyte exposure to high E2 levels on perinatal outcomes remains unknown. Thus, a retrospective cohort study was conducted to explore the effect of high E2 level induced by controlled ovarian stimulation (COH) on further outcomes after frozen embryo transfer (FET). The study included all FET cycles (n = 10,581) between 2014 and 2017. All cycles were categorized into three groups according to the E2 level on the day of the human Chorionic Gonadotropin trigger. Odds ratios (ORs) and their confidence intervals (CIs) were calculated to evaluate the association between E2 level during COH and pregnancy outcomes and subsequent neonatal outcomes. From our findings, higher E2 level was associated with lower percentage of chemical pregnancy, clinical pregnancy, ongoing pregnancy, and live birth as well as increased frequency of early miscarriage. Preterm births were more common among singletons in women with higher E2 level during COH (aOR1 = 1.93, 95% CI: 1.22–3.06; aOR2 = 2.05, 95% CI: 1.33–3.06). Incidence of small for gestational age (SGA) was more common in both singletons (aOR1 = 2.01, 95% CI: 1.30–3.11; aOR2 = 2.51, 95% CI: 1.69–3.74) and multiples (aOR1 = 1.58, 95% CI: 1.03–2.45; aOR2 = 1.99, 95% CI: 1.05–3.84) among women with relatively higher E2 level. No association was found between high E2 level during COH and the percentage of macrosomia or large for gestational age. In summary, oocyte exposure to high E2 level during COH should be brought to our attention, since the pregnancy rate decreasing and the risk of preterm birth and SGA increasing following FET.
Anatase phase NOx/S6+–TiO2 (x= 0, 1) film with high solar-driven activity has been successfully prepared via electro-assisted oxidation processes. The morphological and structural properties of the film were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction, while the optical property was detected by UV-vis-NIR absorption spectroscopy. The results showed that the NOx/S6+–TiO2 film was composed of “flower-like” microvoids structure and displayed broad and strong optical absorption at around 544 and 1500 nm. Transient photocurrent response, photoluminescence spectroscopy, and electrochemical impedance spectroscopy indicated that the generation and separation of photogenerated charges were significantly enhanced under simulated solar irradiation. The NOx/S6+–TiO2 film exhibited excellent photoelectrocatalytic activity for the degradation of methyl orange (MO), and the decoloration rate and TOC removal respectively reached 98.97 and 59.44% at 20 min under solar irradiation. The film still had good stability after reusing ten times. Furthermore, a possible mechanism of photoelectrocatalysis was suggested in MO degradation by using NOx/S6+–TiO2 film.
This paper introduces a dual-user training system whose design is based on an energetic approach. This kind of system is useful for supervised hands-on training where a trainer interacts with a trainee through two haptic devices, in order to practice on a manual task performed on a virtual or teleoperated robot (e.g., for an Minimally Invasive Surgery (MIS) task in a surgical context). This paper details the proof of stability of an Energy Shared Control (ESC) architecture we previously introduced for one degree of freedom (d.o.f.) devices. An extension to multiple degrees of freedom is proposed, along with an enhanced version of the Adaptive Authority Adjustment function. Experiments are carried out with 3 d.o.f. haptic devices in free motion as well as in contact contexts in order to show the relevance of this architecture.
In an effort to improve the reliability of Arctic sea-ice predictions, an ensemble-based Arctic Ice Ocean Prediction System (ArcIOPS) has been developed to meet operational demands. The system is based on a regional Arctic configuration of the Massachusetts Institute of Technology general circulation model. A localized error subspace transform ensemble Kalman filter is used to assimilate the weekly merged CryoSat-2 and Soil Moisture and Ocean Salinity sea-ice thickness data together with the daily Advanced Microwave Scanning Radiometer 2 (AMSR2) sea-ice concentration data. The weather forecasts from the Global Forecast System of the National Centers for Environmental Prediction drive the sea ice–ocean coupled model. The ensemble mean sea-ice forecasts were used to facilitate the Chinese National Arctic Research Expedition in summer 2017. The forecasted sea-ice concentration is evaluated against AMSR2 and Special Sensor Microwave Imager/Sounder sea-ice concentration data. The forecasted sea-ice thickness is compared to the in-situ observations and the Pan-Arctic Ice-Ocean Modeling and Assimilation System. These comparisons show the promising potential of ArcIOPS for operational Arctic sea-ice forecasts. Nevertheless, the forecast bias in the Beaufort Sea calls for a delicate parameter calibration and a better design of the assimilation system.
We report new U–Pb zircon age data, zircon in situ oxygen isotope, mineral chemistry, whole-rock geochemistry and Sr–Nd isotopic compositions from the Early Devonian ultrapotassic Gucheng pluton in the North China Craton, and discuss its petrogenesis. The Gucheng pluton is exposed in the northern part of the North China Craton and forms a composite intrusion, consisting of K-feldspar-bearing clinopyroxenite, clinopyroxene-bearing syenite and alkali-feldspar syenite. Mineral phases in these lithologies include clinopyroxene (Wo43–48En19–35Fs18–38), sanidine (An0Ab3–11Or89–97), and subordinate titanite, andradite and Na-feldspar. These rocks show homogeneous Sr but variable Nd isotopic compositions, and have relatively high zircon in situ oxygen isotopes (δ18O = 5.2–6.7). The Gucheng plutonic rocks formed through fractional crystallization and accumulation from ultrapotassic magmas, which were originated from partial melting of metasomatic vein systems in the subcontinental lithospheric mantle of the North China Craton. These vein networks developed as a result of the reactions of fluids derived from subducted pelitic sediments on the downgoing Palaeo-Asian ocean floor with the enriched, subcontinental lithospheric mantle peridotites. Sensitive high-resolution ion microprobe (SHRIMP) U–Pb zircon dating has revealed a crystallization age of 415 Ma for the timing of the emplacement of the Gucheng pluton that marks the early stages of alkaline magmatism associated with the Andean-type continental margin evolution along the northern edge of the North China Craton facing the Palaeo-Asian Ocean.
Intestinal barrier inflammatory damage is commonly accompanied by hypoxia. The hypothesis that dietary Acanthopanax senticosus polysaccharides (ASPS) might modulate the hypoxia-inducible factor-1α (HIF-1α) signalling pathway and contribute to attenuate intestinal injury was tested in lipopolysaccharide (LPS)-challenged piglets. Thirty-six weaned pigs were randomly allocated to one of the following three groups: (1) basal diet + saline challenge; (2) basal diet + LPS challenge; (3) basal diet with 800 mg/kg ASPS + LPS challenge. LPS was injected at 15, 18 and 21 d, and intestinal sections were sampled following blood collection at 21 d . The results showed ASPS reversed (P < 0·05) LPS-induced decrease in average daily feed intake and rise (P < 0·05) of diarrhoea incidence and index. Biochemical index reflecting gut barrier damage and function involving ileal pro-inflammatory cytokines (TNF-α and IL-1β) and enzyme activity (diamine oxidase and lactase), as well as circulatory d-xylose, was normalised (P < 0·05) in LPS-challenged piglets receiving ASPS. ASPS also ameliorated intestinal morphological deterioration of LPS-challenged piglets, proved by elevated ileal villus height (P < 0·05) and improved appearance of epithelial villus and tight junction ultrastructure. Moreover, ASPS prevented LPS-induced amplification of inflammatory mediators, achieved by depressed ileal mRNA abundance of TNF-α, inducible NO synthase and IL-1β concentration. Importantly, ileal protein expressions of HIF-1α, cyclo-oxygenase-2 (COX-2) and NFκB p65 were also suppressed with ASPS administration (P < 0·05). Collectively, these results suggest the improvement of mucosal inflammatory damage and diarrhoea in immune stress piglets is possibly associated with a novel finding where HIF-1α/COX-2 pathway down-regulation is involved in NFκB p65-inducible releasing of inflammatory cytokines by dietary ASPS.
Mingantu Spectral Radioheliograph (MUSER) is an aperture-synthesis imaging telescope, dedicated to observe the Sun, operating on multiple frequencies in dm to cm range. The ability of MUSER to get images and measure Stokes I and V parameters simultaneously at many frequencies in a wide band is of fundamental importance. It allows one to approach/solve such important problems as measuring the strength, geometry and dynamics of magnetic field at coronal heights. Here we consider some of the recently developed radio physics methods to be used for solving the problems. These methods allow us to obtain information that is unattainable in other areas of the electromagnetic spectrum.
A kind of novel Ni–P gradient coating/stannate conversion film was deposited on AZ91D magnesium alloy (AZ91D alloy) by an integrative method involved stannate conversion and electroless plating. The results indicated that using sodium hypophosphite concentrations varied as 5, 10, 22, 46, and 60 g/L in the bath, the electroless Ni–P gradient coating with typical cell morphologies was successfully prepared, and the structures transited from crystalline → microcrystalline → amorphous were obtained as increasing P content from 3.31 to 12.58 wt%. Furthermore, the corrosion morphologies, polarization curves, and the electrochemical impedance spectroscopy result indicated that the corrosion resistance of AZ91D alloy substrate was significantly improved and the corrosion resistance of Ni–P gradient coating was superior than that of stannate conversion film, which might be attributed to the gradient structure and rising P content with unique function.
The Zhangguangcai Range in the Xing’an Mongolian Orogenic Belt, NE China, contains Early Jurassic (c. 188 Ma) Dabaizigou (DBZG) porphyritic dolerite. Compared with other island-arc mafic rocks, the DBZG dolerite is characterized by high trace-element contents, relatively weak Nb and Ta enrichments, and no Zr, Hf or Ti depletions, similar to OIB-type rocks. Analysed rocks have (87Sr/86Sr)i ratios of 0.7033–0.7044, relatively uniform positive ɛNd(t) values of 2.3–3.2 and positive ɛHf(t) values of 8.5–17.1. Trace-element and isotopic modelling indicates that the DBZG mafic rocks were generated by partial melting of asthenospheric mantle under garnet- to spinel-facies conditions. The occurrence of OIB-like mafic intrusion suggests significant upwelling of the asthenosphere in response to lithospheric attenuation caused by continental rifting. These processes occurred in an incipient continental back-arc environment in the upper plate of a palaeo-Pacific slab subducting W–NW beneath East Asia.
Summarizing content contributed by individuals can be challenging, because people make different lexical choices even when describing the same events. However, there remains a significant need to summarize such content. Examples include the student responses to post-class reflective questions, product reviews, and news articles published by different news agencies related to the same events. High lexical diversity of these documents hinders the system’s ability to effectively identify salient content and reduce summary redundancy. In this paper, we overcome this issue by introducing an integer linear programming-based summarization framework. It incorporates a low-rank approximation to the sentence-word cooccurrence matrix to intrinsically group semantically similar lexical items. We conduct extensive experiments on datasets of student responses, product reviews, and news documents. Our approach compares favorably to a number of extractive baselines as well as a neural abstractive summarization system. The paper finally sheds light on when and why the proposed framework is effective at summarizing content with high lexical variety.
Measurement of runaway electron beam (REB) is essential to investigate behavior of runaway electrons produced in nanosecond-pulse gas discharge. A Faraday cup is designed to measure the REB current in nanosecond-pulse discharge when the applied dV/dt is 75 kV/ns. The Faraday cup considers the impendence match with the oscilloscope and the design of the receiving part. The experimental results show that the measured REB current has a rise time of 348 ps and a full width at half maximum of 510 ps. The comparison of the measurement results by the Faraday cup and a REB collector confirm that the Faraday cup is able to measure REB current in nanosecond-pulse discharge. Furthermore, consecutive waveforms of the REB currents show stable results by using the designed Faraday cup. In addition, effects of the interelectrode gap, gas pressure, and cathode material on the REB current are investigated by the designed Faraday cup, and the measurement results provide characteristics of REB current under different conditions. The REB current decreases when the gap spacing or gas pressure increases. REB current increases with the cathode diameter. It indicates that the high-energy electrons are generated not only at the edge of the cathode but also on the side surface of the cathode.
The novel visible-light-responsive direct solid-state Z-scheme g-C3N4/BiOI heterojunction has been synthesized successfully by means of a solid phase calcination method and used for the degradation of microcystin-LR (MC-LR). The layered g-C3N4 disperses on the surface of BiOI microspheres. The samples are characterized by FESEM, HRTEM, XRD, FT-IR, UV-vis spectroscopy, XPS, BET, PL, and Mott–Sckottky. The photocatalytic activity and photodegradation mechanism of the as-prepared g-C3N4/BiOI microsphere photocatalysts are conducted under visible light irradiation using MC-LR as the target pollutant. The g-C3N4/BiOI material exhibits superior photocatalytic performance when compared with pure BiOI, the possible reason is the efficient separation of photogenerated carriers at the interface between g-C3N4 and BiOI. The heterostructure is responsible for the improved separation efficiency of photogenerated electron–hole pairs and thus the higher photocatalytic activity. The possible photocatalytic mechanism is proposed based on relative band positions of these two semiconductors.