Metallic multilayered nanofilms have been extensively studied owing to their unique physical properties and applications. However, studies on the thermal conductivity and electrical resistivity of ...metallic multilayered nanofilms, as their important physical properties, are seldom reported. In this work, Cu/W multilayered nanofilms with periodic thickness varying from 6 to 150 nm were deposited by magnetron sputtering. The resistivities of the Cu/W multilayered nanofilms increase with the decrease of periodic thickness, especially when the periodic thickness is smaller than 37 nm. The resistivities of the multilayered nanofilms fit well with the Fuchs–Sondheimer and Mayadas–Shatzkes (FS–MS) model, which considers both interface scattering and grain boundary scattering. The thermal conductivities of the Cu/W multilayered nanofilms were measured by the three-omega (3ω) method, which decrease with a decrease of periodic thickness initially and increase at the smallest periodic thickness of 6 nm. The Boltzmann transport equation (BTE)-based model was used, to explain the periodic thickness-dependent thermal conductivity of metallic multilayered nanofilms by considering the contributions from both phonon and electron heat transport processes, where the calculated thermal conductivities agree well with the measured ones. The electrical resistivity and thermal conductivity strongly depend on the microstructures of the multilayered nanofilms.
In this study, a surface-enhanced resonance Raman scattering (SERRS) method has been developed for the accurate detection and identification of carbapenem-resistant and carbapenem-sensitive
. A total ...of 89 human isolates of Enterobacteriaceae, comprising 41 strains of carbapenem-sensitive
(CSEC) and 48 strains of carbapenem-resistant
(CREC), were tested to assess the feasibility of our proposed SERRS method as a clinical tool, and the results showed almost 100% accuracy.
Liquid biopsy is ideal for early diagnosis of cancer and for prognosis upon treatment. Wen et al describe a methylated CpG tandems amplification and sequencing method to profile hypermethylated CpG ...islands genome-widely in cell-free DNA, and further identify high performance markers in blood for potential detection of early stage bepatocellular carcinoma.
The objective was to investigate the efficacy of different doses of levothyroxine therapy among pregnant women exhibiting high-normal thyroid stimulating hormone levels and positive thyroid ...peroxidase antibodies throughout the first half of pregnancy.
Pregnant women exhibiting high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positivity throughout the initial half of pregnancy were selected from January 2021 to September 2023. Based on the different doses of levothyroxine, the pregnant women were categorized into the nonintervention group (G
, 122 women), 25 µg levothyroxine intervention group (G
, 69 women), and 50 µg levothyroxine intervention group (G
, 58 women). Serum parameters, gastrointestinal symptoms, small intestinal bacterial overgrowth (SIBO), maternal and neonatal outcomes were compared after the intervention among the three groups.
After the intervention, in the G
and G
groups, the thyroid stimulating hormone, triglyceride and low-density lipoprotein levels were notably less in contrast to those in the G
group (P < 0.05). The rates of abdominal distension and SIBO in the G
and G
groups were notably lower in contrast to the G
group (P = 0.043 and 0.040, respectively). The G
group had a lower rate of spontaneous abortion and premature membrane rupture than the G
group (P = 0.01 and 0.015, respectively). Before 11
weeks of gestation and at thyroid peroxidase antibodies levels ≥ 117 IU/mL, in contrast to the G
group, the G
group experienced a decreased rate of spontaneous abortion (P = 0.008). The G
group had significantly higher newborn weight than the G
group (P = 0.014), as well as a notably longer newborn length than the G
and G
groups (P = 0.005).
For pregnant women with high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positive during the first half of pregnancy, supplementation with 50 µg levothyroxine was more effective in improving their blood lipid status and gastrointestinal symptoms, reducing the incidence of SIBO and premature rupture of membranes, and before 11
weeks, TPOAb ≥ 117 IU/mL proved more beneficial in mitigating the risk of spontaneous abortion.
Abstract
N
6
-methyladenosine (m
6
A) has been demonstrated to regulate RNA metabolism and various biological processes, including gametogenesis and embryogenesis. However, the landscape and function ...of m
6
A at single cell resolution have not been extensively studied in mammalian oocytes or during pre-implantation. In this study, we developed a single-cell m
6
A sequencing (scm
6
A-seq) method to simultaneously profile the m
6
A methylome and transcriptome in single oocytes/blastomeres of cleavage-stage embryos. We found that m
6
A deficiency leads to aberrant RNA clearance and consequent low quality of
Mettl3
Gdf9
conditional knockout (cKO) oocytes. We further revealed that m
6
A regulates the translation and stability of modified RNAs in metaphase II (MII) oocytes and during oocyte-to-embryo transition, respectively. Moreover, we observed m
6
A-dependent asymmetries in the epi-transcriptome between the blastomeres of two-cell embryo. scm
6
A-seq thus allows in-depth investigation into m
6
A characteristics and functions, and the findings provide invaluable single-cell resolution resources for delineating the underlying mechanism for gametogenesis and early embryonic development.
subsp.
serovar Derby (
Derby) is one of the most common serotypes responsible for salmonellosis in humans and animals. The two main sequence types (ST) observed in China are ST40 and ST71, with ST40 ...presently being the most common in Shenzhen. Recent years have seen an increasing number of cases of salmonella caused by ST40
. Derby, but the epidemiology is not clear. We gathered 314 ST40
. Derby isolates from food and patient samples for 11 years in Shenzhen; 76 globally prevalent representative strains were also collected. Whole-genome sequencing (WGS) combined with drug resistance phenotyping was used to examine population structural changes, inter-host associations, drug resistance characteristics, and the food-transmission risks of ST40
. Derby in Shenzhen over this period. The
evolutionary tree is divided into five clades, and the strains isolated in Shenzhen were primarily concentrated in Clades 2, 4, and 5, and thus more closely related to strains from Asian (Thailand and Vietnam) than European countries. Our 11-year surveillance of
. Derby in Shenzhen showed that Clades 2, 4, and 5 are now the dominant epidemic branches, and branches 2 and 5 are heavily multi-drug resistant. The main resistance pattern is ampicillin-tetracycline-ciprofloxacin-chloramphenicol-nalidixic acid-streptomycin-sulfamethoxazole/trimethoprim. This may lead to a trend of increasing resistance to ST40
. Derby in Shenzhen. Using a segmentation of ≤3 SNP among clone clusters, we discovered that Clades 2 and 4 contained multiple clonal clusters of both human- and food-derived strains. The food-derived strains were mainly isolated from pig liver, suggesting this food has a high risk of causing disease outbreaks in Shenzhen.
Leaf chlorophyll content is an important indicator of the physiological and ecological functions of plants. Accurate estimation of leaf chlorophyll content is necessary to understand energy, carbon, ...and water exchange between plants and the atmosphere. The leaf chlorophyll content index (CCI) of 109 Moso bamboo samples (19 for training data, 19 for validation data, and 71 for extrapolation data) was measured from December 2019 to May 2021, while their corresponding red–green–blue (RGB) images were acquired using an unmanned aerial vehicle (UAV) platform. A method for estimating leaf CCI based on constructing relationships between field leaf CCI measurements and UAV RGB images was evaluated. The results showed that a modified excess blue minus excess red index and 1.4 × H-S in the hue–saturation–value (HSV) color space were the most suitable variables for estimating the leaf CCI of Moso bamboo. No noticeable difference in accuracy between the linear regression model and backpropagation neural network (BPNN) model was found. Both models performed well in estimating leaf CCI, with an R2 > 0.85 and relative root mean square error (RMSEr) < 15.0% for the validation data. Both models failed to accurately estimate leaf CCI during the leaf-changing period (April to May in off-year), with the problems being overestimation in low leaf CCI and underestimation in high leaf CCI values. At a flight height of 120 m and illumination between 369 and 546 W/m2, the CCI for an independent sample dataset was accurately estimated by the models, with an R2 of 0.83 and RMSEr of 13.78%. Flight height and solar intensity played a role in increasing the generality of the models. This study provides a feasible and straightforward method to estimate the leaf CCI of Moso bamboo based on UAV RGB images.
Lactoferrin (LTF), an important first line defense molecule against infection, is a common target for humoral autoimmune reactions in humans. Since LTF is a multifunctional protein capable of ...activating innate immune cells via various surface receptors, we hypothesized that LTF-containing immune complexes (ICs) (LTF-ICs), likely formed in patients with high titer anti-LTF autoantibodies, could possess unique monocyte/macrophage-activating properties compared with other ICs. ELISA analysis on serum samples from rheumatoid arthritis (RA) patients (n = 80) and healthy controls (n = 35) for anti-LTF autoantibodies confirmed a positive correlation between circulating LTF-specific IgG and RA. ICs between human LTF and LTF-specific IgG purified from patient sera or immunized rabbits and mice, but not control ICs, LTF or Abs alone, elicited strong production of TNF-α and IL-1β by freshly fractionated human peripheral blood monocytes and monocytes-derived macrophages. Furthermore, LTF-ICs utilized both membrane-anchored CD14 and CD32a (FcγRIIa) to trigger monocyte activation in an internalization-, Toll-like receptor (TLR)4- and TLR9-dependent manner, and also that LTF-IC-induced cytokine production was blocked by specific inhibitors of caspase-1, NF-κB and MAPK. These results uncover a possible pathway for LTF-ICs perpetuating local inflammation and contributing to the pathogenesis of autoimmune diseases by triggering activation of infiltrating monocytes or tissue macrophages in vivo.
The authors describe the preparation of a chiral graphene oxides (GOs) by covalent attachment of D- or L-cysteine using a one-step hydrothermal method. The resulting chiral functionalized GOs shows ...circular dichroism with intensities similar to those produced by the cysteines. This indicates that the chirality of cysteines is well preserved in the chiral GOs. The material is reasonably stable at temperatures from 20 to 200 °C and at pH values from 0 to 14. A glassy carbon electrode (GCE) was modified with the chiral GOs and then tested for recognition capability for L- and D-tartrate (0.5 mM). The enantioselectivity of the chiral GOs appears to be the result of a synergistic effect where GO increases the conductivity and cysteine provides the chiral environment. The method is assumed to provide a useful general scheme for development of advanced carbonaceous materials with chiral recognition capabilities.
Graphical abstract
Chiral graphene oxides produced by covalently attaching chiral amino acids displays effective enantioselective recognition.
High-performance radiation tolerance materials are crucial for the success of future advanced nuclear reactors. In this paper, we present a further investigation that the “vein-like” nanochannel ...films can enhance radiation tolerance under ion irradiation at high temperature and post-irradiation annealing. The chromium nitride (CrN) nanochannel films with different nanochannel densities and the compact CrN film are chosen as a model system for these studies. Microstructural evolution of these films were investigated using Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Elastic Recoil Detection (ERD) and Grazing Incidence X-ray Diffraction (GIXRD). Under the high fluence He+ ion irradiation at 500 °C, small He bubbles with low bubble densities are observed in the irradiated nanochannel CrN films, while the aligned large He bubbles, blistering and texture reconstruction are found in the irradiated compact CrN film. For the heavy Ar2+ ion irradiation at 500 °C, the microstructure of the nanochannel CrN RT film is more stable than that of the compact CrN film due to the effective releasing of defects via the nanochannel structure. Under the He+ ion irradiation and subsequent annealing, compared with the compact film, the nanochannel films have excellent performance for the suppression of He bubble growth and possess the strong microstructural stability. Basing on the analysis on the sizes and number densities of bubbles as well as the concentrations of He retained in the nanochannel CrN films and the compact CrN film under different experimental conditions, potential mechanism for the enhanced radiation tolerance are discussed. Nanochannels play a crucial role on the release of He/defects under ion irradiation. We conclude that the tailored “vein-like” nanochannel structure may be used as advanced radiation tolerance materials for future nuclear reactors.
•Release of defects and He atoms via designed nanochannel films was realized.•Microstructural evolution under irradiation and annealing were studied.•Nucleation and growth of He bubbles were suppressed in nanochannel films.•Enhanced microstructural stability of nanochannel films was achieved.
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