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The gut microbiota plays an important role in animals’ survival in their local environments. The intertidal rocky shore is a key interface of oceanic, atmospheric and terrestrial environments, and the transmission modes of microbes between an intertidal host and the environment are complex and largely ignored. In the present study, we characterized the gut microbiota of the intertidal snail Nerita yoldii, which is experiencing a northward range shift under the combined impacts of climate change and anthropogenic seascape transformation, and also determined the nearby environmental microbiota on the rock and in the seawater at five locations along the snail's distribution range in China. The gut microbial communities were significantly different from the environmental microbial communities, and the dominant phyla were Tenericutes, Cyanobacteria and Bacteroidetes, and Proteobacteria in the gut, rock and seawater microbial communities, respectively. At the genus level, Mycoplasma, with a relative abundance of 48.0 ± 10.2%, was the dominant genus in the gut microbial community, however, the relative abundances of this genus on the rock and in the water were low. These results imply that the gut microbial community of the intertidal snail N. yoldii is relatively independent from the environmental microbial community, and the dominant genus Mycoplasma in the gut, that is rare in the environment, can potentially assist the snail living in the harsh intertidal environment, especially at its northernmost distribution range edge.
Sarcopenia is a core contributor to several health consequences, including falls, fractures, physical limitations and disability. The pathophysiological processes of sarcopenia may be counteracted with the proper diet, delaying sarcopenia onset. Dietary pattern analysis is a whole diet approach used to investigate the relationship between diet and sarcopenia. Here, we aimed to investigate this relationship in an elderly Chinese population. A cross-sectional study with 2423 participants aged more than 60 years was performed. Sarcopenia was defined based on the guidelines of the Asian Working Group for Sarcopenia, composed of low muscle mass plus low grip strength and/or low gait speed. Dietary data were collected using a FFQ that included questions on 100 food items along with their specified serving sizes. Three dietary patterns were derived by factor analysis: sweet pattern, vegetable pattern and animal food pattern. The prevalence of sarcopenia was 16·1 %. The higher vegetable pattern score and animal food pattern score were related to lower prevalence of sarcopenia (Ptrend = 0·006 and < 0·001, respectively); the multivariate-adjusted OR of the prevalence of sarcopenia in the highest v. lowest quartiles were 0·54 (95 % CI 0·34, 0·86) and 0·50 (95 % CI 0·33, 0·74), separately. The sweet pattern score was not significantly related to the prevalence of sarcopenia. The present study showed that vegetable pattern and animal food pattern were related to a lower prevalence of sarcopenia in Chinese older adults. Further studies are required to clarify these findings.
Several observational studies have investigated the association of insomnia with psychiatric disorders. Such studies yielded mixed results, and whether these associations are causal remains unclear. Thus, we aimed to identify the causal relationships between insomnia and five major psychiatric disorders.
The analysis was implemented with six genome-wide association studies; one for insomnia and five for psychiatric disorders (attention-deficit/hyperactivity disorder, autism spectrum disorder, major depressive disorder, schizophrenia, and bipolar disorder). A heterogeneity in dependent instrument (HEIDI) approach was used to remove the pleiotropic instruments, Mendelian randomization (MR)-Egger regression was adopted to test the validity of the screened instruments, and bidirectional generalized summary data-based MR was performed to estimate the causal relationships between insomnia and these major psychiatric disorders.
We observed significant causal effects of insomnia on the risk of autism spectrum disorder and bipolar disorder, with odds ratios of 1.739 (95% confidence interval: 1.217–2.486, p = 0.002) and 1.786 (95% confidence interval: 1.396–2.285, p = 4.02 × 10−6), respectively. There was no convincing evidence of reverse causality for insomnia with these two disorders (p = 0.945 and 0.546, respectively). When insomnia was considered as either the exposure or outcome variable, causal estimates for the remaining three psychiatric disorders were not significant.
Our results suggest a causal role of insomnia in autism spectrum disorder and bipolar disorder. Future disease models should include insomnia as a factor for these two disorders to develop effective interventions. More detailed mechanism studies may also be inspired by this causal inference.
To investigate the hypothesis that folic acid supplementation and dietary folate intake before conception and during pregnancy reduce the risk of small for gestational age (SGA) and to examine the joint effect of folic acid supplementation and dietary folate intake on the risk of SGA.
Participants were interviewed by trained study interviewers using a standardized and structured questionnaire. Information on birth outcomes and maternal complications was abstracted from medical records and dietary information was collected via a semi-quantitative FFQ before conception and during pregnancy.
A birth cohort data analysis using the 2010–2012 Gansu Provincial Maternity and Child Care Hospital.
Women (n 8758) and their children enrolled in the study.
Folic acid supplementation was associated with a reduced risk of SGA (OR = 0·72, 95 % CI 0·60, 0·86), with the reduced risk seen mainly for SGA at ≥37 weeks of gestational age (OR = 0·70, 95 % CI 0·58, 0·85) and nulliparous SGA (OR = 0·67, 95 % CI 0·54, 0·84). There was no significant association between dietary folate intake and SGA risk.
Our study suggested that folic acid supplementation was associated with a reduced risk of SGA and the risk varied by preterm status and parity.
Previous studies have shown that the Dietary Approaches to Stop Hypertension (DASH) diet might contribute to managing risk factors of non-alcoholic fatty liver disease (NAFLD), but evidence is limited. We examined the association of DASH diet score (DASH-DS) with NAFLD, as well as the intermediary effects of serum retinol-binding protein-4 (RBP4), serum high-sensitivity C-reactive protein (hs-CRP), serum TAG, homeostasis model assessment of insulin resistance (HOMA-IR) and BMI.
We performed a cross-sectional analysis of a population-based cohort study. Dietary data and lifestyle factors were assessed by face-to-face interviews and the DASH-DS was then calculated. We assessed serum RBP4, hs-CRP and TAG and calculated HOMA-IR. The presence and degree of NAFLD were determined by abdominal sonography.
Guangzhou Nutrition and Health Study participants, aged 40–75 years at baseline (n 3051).
After adjusting for potential covariates, we found an inverse association between DASH-DS and the presence of NAFLD (Ptrend = 0·009). The OR (95 % CI) of NAFLD for quintiles 2–5 were 0·78 (0·62, 0·98), 0·74 (0·59, 0·94), 0·69 (0·55, 0·86) and 0·77 (0·61, 0·97), respectively. Path analyses indicated that a higher DASH-DS was associated with lower serum RBP4, hs-CRP, TAG, HOMA-IR and BMI, which were positively associated with the degree of NAFLD.
Adherence to the DASH diet was independently associated with a marked lower prevalence of NAFLD in Chinese adults, especially in women and those without abdominal obesity, and might be mediated by reducing RBP4, hs-CRP, TAG, HOMA-IR and BMI.
Imaging studies have shown that the subcallosal region (SCR) volume was decreased in patients with major depressive disorder (MDD). However, whether the volumetric reductions in the SCR are due to thinning of the cortex or a loss of surface area (SA) remains unclear. In addition, the relationship between cortical measurements of the SCR and age through the adult life span in MDD remains unclear.
We used a cross-sectional design from 114 individuals with MDD and 112 matched healthy control (HC) individuals across the adult life span (range: 18–74 years). The mean cortical volume (CV), SA and cortical thickness (CT) of the SCR were computed using cortical parcellation based on FreeSurfer software. Multivariate analyses of covariance models were performed to compare differences between the MDD and HC groups on cortical measurements of the SCR. Multiple linear regression models were used to test age-by-group interaction effects on these cortical measurements of the SCR.
The MDD had significant reductions in the CV and SA of the left SCR compared with HC individuals after controlling of other variables. The left SCR CV and SA reductions compared with matched controls were observed only in early adulthood patients. We also found a significant age-related CT reduction in the SCR both in the MDD and HC participants.
The SCR volume reduction was mainly driven by SA in MDD. The different trajectories between the CT and SA of the SCR with age may provide valuable information to distinguish pathological processes and normal ageing in MDD.
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.
The magnetism and microstructure of Cr25Ni35Nb and Cr35Ni45Nb alloy tubes after 5 years of service were investigated in this paper. The saturation magnetization of the Cr25Ni35Nb alloy tube in the thickness direction is more than 20 emu/g, and the tube becomes ferromagnetic. The inner and outer walls of Cr35Ni45Nb alloy tubes also become ferromagnetic. But the saturation magnetization of the Cr35Ni45Nb alloy tubes approaches to zero in the center zone. The primary carbides M7C3 and NbC are changed into M23C6 and G phase at the outer region of the furnace tube. However, the M23C6-type carbides were replaced by carbon-rich carbides M7C3 at the carburization zone. Cr-depleted zones are formed at the inner and outer walls of the furnace tubes owing to oxidation. Carburization and oxidation reduce the Cr content of the matrix. Accordingly, the saturation magnetization is very high at the carburization zone and Cr-depleted zone. The magnetism of Cr25Ni35Nb and Cr35Ni45Nb alloy tubes has a high correlation with the Cr content of the matrix. Carburization and oxidation are the main reasons that make the paramagnetic ethylene pyrolysis furnace tube change to ferromagnetic.
Outside surface fluctuations of inertial confinement fusion (ICF) capsule greatly affect the implosion performance. An atomic force microscope (AFM)-based profilometer is developed to precisely characterize the capsule surface with nanometer resolution. With the standard nine surface profiles and the complete coverage data, 1D and 2D power spectra are obtained to quantitatively qualify the capsule. Capsule center fast aligning, orbit traces automatic recording, 3D capsule orientation have been studied to improve the accuracy and efficiency of the profilometer.
In this study, hematite nanoparticles (α-Fe2O3 NPs) were synthesized by hydrothermal method, with morphologies (e.g., nanorhombohedra, nanobars, and nanospheres) facilely tuned by changing the concentrations of glycol in the hydrothermal solution. Then a low-cost and scalable electrophoretic deposition method was used to fabricate nanostructured α-Fe2O3 films as photoanodes for solar hydrogen generation. It was found that the film of α-Fe2O3 nanobars showed the highest photoelectrochemical (PEC) performance compared to those films of α-Fe2O3 nanorhombohedra and nanospheres, with photocurrent density reaching 0.7 mA/cm2 at 0.6 V versus Ag/AgCl. This PEC improvement may be related to the smaller diameters of nanobars shortening the carrier migration distance, reducing the recombination rate of photo-generated carriers. Moreover, all the α-Fe2O3 films showed much higher PEC performances with surface modified by Sn4+, mainly due to the reduced surface charge recombination, as the Sn4+ doped overlayer passivated surface defects. For the film of α-Fe2O3 nanobars, the photocurrent density was increased by 100%, reaching 1.4 mA/cm2 at 0.6 V versus Ag/AgCl.
A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.
A new route for atom-economical synthesis of functional polymers was developed. Oxidative polycoupling of 3,5-dimethyl-1-phenylpyrazole with 4,4’-(α,ω-alkylenedioxy) bis(diphenylacetylene)s and 1,2-diphenyl-1,2-bis[4-(phenylethynyl)phenyl]ethene, respectively, were catalyzed by [Cp*RhCl2]2, 1,2,3,4-tetraphenylcyclopenta-1,3-diene and copper(II) acetate in dimethylformamide under stoichiometric imbalance conditions, affording soluble poly(pyrazolylnaphthalene)s in satisfactory yields (isolation yield up to 82%) with high molecular weights (Mw up to 35700). All the polymers were thermally stable, losing little of their weight at high temperatures of 323–422 oC. They possessed good film-forming property and their thin solid films showed high refractive indices (RI = 1.747–1.593) in a wide wavelength region of 400−1000 nm. The polymer carrying tetraphenylethene unit displayed a phenomenon of aggregation-induced emission and showed enhanced light emission in the aggregated state.
High rate of charge carrier recombination is a critical factor limiting the photocatalytic activity of g-C3N4. In this contribution, we demonstrate that this issue can be alleviated by constructing a plasmonic photocatalyst with tailored plasmonic-metal nanostructures, i.e., core–shell-typed Ag@SiO2 nanoparticles. Compared with pure g-C3N4, the photocatalytic hydrogen production activity was enhanced by 63% for Ag@SiO2/g-C3N4. As analysis from the photoluminescence results, the enhancement could be attributed to that plasmonic nanostructures favored the separation of electron–hole pairs in the semiconductor due to localized surface plasmons resonance effect. It was found that the silica shell between the Ag nanoparticles and g-C3N4 was essential for the better photocatalytic activity of Ag@SiO2/g-C3N4 than that of Ag/g-C3N4 by limiting the energy-loss Förster energy transfer process.
LiMn2O4 nanowires have been synthesized by a two-step approach. γ-MnOOH nanowires are firstly synthesized by hydrothermal method and after further sintering with LiOH at 750 °C for about 3 h, the wire-like LiMn2O4 can be obtained. The structure of the final product is characterized by x-ray diffraction using Rietveld refinement. Its electrochemical performance is investigated by galvanostatic tests. The as-prepared LiMn2O4 nanowires display excellent cyclability. The LiMn2O4 nanowires with good cycle stability may be beneficial from the structural stability of LiMn2O4 crystal cell and one-dimensional nanostructure.
A 5′-flanking region and partial open reading frame (ORF) of the β-actin gene (GenBank accession No. EF026001) of Nile tilapia (Oreochromis niloticus) was cloned by polymerase chain reaction (PCR) amplification. The segment included a 1643 bp regulatory sequence and a 90 bp partial ORF which encoded a 30-amino-acid peptide. The regulatory sequence comprised a 108 bp 5′ proximal promoter, the first untranslated exon and the first intron of the β-actin gene. The proximal promoter region contained elements that were critical for transcription activity, including a CCAAT, TATA and CArG box located at –92, –29 and –62 bp upstream of the transcription initiation site, respectively. The regulatory sequence was inserted into the promoterless pDsRed2-1 vector to construct the expressing vector pNA-DsRed. The linearized pNA-DsRed was microinjected into the fertilized eggs of Tanichthys albonubes. The expression of the DsRed2 gene in transgenic fish could be observed under the microfluoroscope and anatomical lens. The results showed that the β-actin gene promoter possessed effective transcription activity.
By using a Reynolds-averaged two-dimensional computation of a turbulent
an airfoil at post-stall angles of attack, we show that the massively separated
disordered unsteady flow can be effectively controlled by periodic blowing–suction
near the leading edge with low-level power input. This unsteady forcing
the evolution of the separated shear layer to promote the formation of
lifting vortices, which in turn interact with trailing-edge vortices in
manner and thereby alter the global deep-stall flow field. In a certain
range of post-stall
angles of attack and forcing frequencies, the unforced random separated
become periodic or quasi-periodic, associated with a significant lift enhancement.
opens a promising possibility for flight beyond the static stall to a much
of attack. The same local control also leads, in some situations, to a
reduction of drag.
On a part of the airfoil the pressure fluctuation is suppressed as well,
be beneficial for high-α buffet control. The computations are in
with several recent post-stall flow control experiments. The physical mechanisms
responsible for post-stall flow control, as observed from the numerical
explored in terms of nonlinear mode competition and resonance, as well
dynamics. The leading-edge shear layer and vortex shedding from the trailing
are two basic constituents of unsteady post-stall flow and its control.
Since the former
has a rich spectrum of response to various disturbances, in a quite wide
natural frequency of both constituents can shift and lock-in to the forcing
or its harmonics. Thus, most of the separated flow becomes resonant, associated
much more organized flow patterns. During this nonlinear process the coalescence
of small vortices from the disturbed leading-edge shear layer is enhanced,
stronger entrainment and hence a stronger lifting vortex. Meanwhile, the
trailing-edge vortex is pushed downstream. The wake pattern also has a
change: the shed vortices of alternate signs tend to be aligned, forming
a train of
close vortex couples with stronger downwash, rather than a Kármán
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