Equivalent amount of B (BEq) can be used to evaluate the thermal neutron shielding property of materials. Based on the calculation of BEq, a novel boron carbide and gadolinium particles reinforced Al ...composite (15%B4C+1%Gd)/Al was designed. The composite was successfully prepared by vacuum hot pressing method. The B4C particles and Gd phase were homogeneously distributed in the Al matrix. The Monte Carlo Particle transport program MCNP simulation and thermal neutron shielding tests demonstrated that the (15%B4C+1%Gd)/Al composite definitely had an almost equivalent neutron shielding property as the 30%B4C/Al composite, which in turn proved the accuracy of the design. The macroscopic transmission cross section (Σ) of (15%B4C+1%Gd)/Al composite was as high as 21.3cm−1, which was better than that of 30%B4C/Al composite. Tension tests indicated that by decreasing B4C content, the elongation of the composite reached as much as 9%. The addition of Gd can replace a part of B4C content in the composite, which can increase the plasticity of the composite, and keep the neutron shielding property simultaneously.
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•(B4C+Gd)/Al composite was designed and prepared by vacuum hot pressing method.•(15%B4C+1%Gd)/Al had better neutron shielding property as 30%B4C/Al.•(15%B4C+1%Gd)/Al had an elongation of 9%, which was better than 30%B4C/Al.
The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, ...propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°<l<125°, |b|<5°) and outer (125°<l<235°, |b|<5°) Galactic plane are detected with 29.1σ and 12.7σ significance, respectively. The outer Galactic plane diffuse emission is detected for the first time in the very- to ultra-high-energy domain (E>10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.
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Summary
What is known and Objective: Clinical investigations into postoperative intravenous patient‐controlled analgesia (PCA) have indicated interindividual differences in fentanyl consumption. ...Cytochrome P450 3A4 (CYP3A4) is the main metabolism enzyme of fentanyl, and single nucleotide polymorphisms within the CYP3A4 gene may contribute to the variability of fentanyl analgesic efficacy. The aim of this study was to investigate whether the most common genetic variation in Chinese, CYP3A4*1G, has an impact on the fentanyl consumption for intravenous PCA in Chinese Han women undergone abdominal total hysterectomy.
Methods: A total of 79 female patients (American Society of Anesthesiologist physical status I or II) scheduled to undergo elective abdominal total hysterectomy were enrolled. All patients received combined spinal–epidural anaesthesia with bupivacaine. Intravenous fentanyl PCA was provided postoperatively for satisfactory analgesia. The doses of fentanyl consumption were recorded 2, 4, 24 and 48 h after the initiation of PCA postoperatively. Pain at rest and adverse effects were measured with rating scales. CYP3A4*1G was screened by means of direct sequencing and further confirmed by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP).
Results and Discussion: Forty‐six patients were GG homozygotes, 27 patients were GA heterozygotes, and six patients were AA homozygotes, respectively. The distribution of the CYP3A4*1G allele was consistent with Hardy–Weinberg equilibrium (P > 0·05). At 2 and 4 h, the doses of fentanyl required for patients with GA/AA genotypes were 80·0 (45·0, 112·5) μg and 120·0 (80, 173·8) μg, respectively, and significantly lower than those for GG homozygotes 91·3 (80·0, 125·0) μg and 169·0 (112·5, 226·3) μg, respectively, P < 0·05. There was trend of decreasing fentanyl consumption at 24 and 48 h in patients with GA/AA genotypes, relative to GG homozygotes, but the difference was not statistical significant (P > 0·05).
What is new and Conclusions: CYP3A4*1G has an impact on the analgesic effect of fentanyl in Chinese Han subjects. Further validation of our results in a well‐powered study would be helpful.
Development of the gut-brain axis in early life may be disturbed by antibiotic use. It has been hypothesized that this disturbance may contribute to development of neurodevelopmental disorders, ...including autism spectrum disorder and attention-deficit hyperactivity disorder. We aimed to assess the association between antibiotic use in early life and the risk of developing attention-deficit hyperactivity disorder or autism spectrum disorder, while controlling for shared genetic and environmental factors in a discordant twin design.
We conducted a cohort study in twins (7-12 years; 25 781 twins) from the Netherlands Twin Register (NTR) and a replication study in the Childhood and Adolescent Twin Study in Sweden (CATSS; 7946 9-year-old twins). Antibiotic use was recorded before age 2 years. Attention-deficit hyperactivity disorder and autism spectrum disorder were parent-reported in the Netherlands Twin Register and register-based in the Childhood and Adolescent Twin Study in Sweden.
Early-life antibiotic use was associated with increased risk of attention-deficit hyperactivity disorder development pooled odds ratio (OR) 1.10, 95% confidence interval (CI) 1.02-1.17 and autism spectrum disorder (pooled OR 1.15, 95% CI 1.06-1.25) in a case-control design. When restricting to monozygotic twin pairs discordant for the outcome, associations disappeared for both disorders in both cohorts (attention-deficit hyperactivity disorder OR 0.90, 95% CI 0.48-1.69 and OR 0.80, 95% CI 0.37-1.76, and autism spectrum disorder OR 0.66, 95% CI 0.38-1.16 and OR 0.29, 95% CI 0.02-4.50, respectively).
Our findings suggest that the association between early-life antibiotic use and risk of attention-deficit hyperactivity and autism spectrum disorder may be confounded by shared familial environment and genetics.
Sheep (
) and goats (
) have, for more than a millennia, been a source of fibres for human use, be it for use in clothing and furnishings, for insulation, for decorative and ceremonial purposes, or ...for combinations thereof. While use of these natural fibres has in some respects been superseded by the use of synthetic and plant-based fibres, increased accounting for the carbon and water footprint of these fibres is creating a re-emergence of interest in fibres derived from sheep and goats. The keratin-associated proteins (KAPs) are structural components of wool and hair fibres, where they form a matrix that cross-links with the keratin intermediate filaments (KIFs), the other main structural component of the fibres. Since the first report of a complete KAP protein sequence in the late 1960s, considerable effort has been made to identify the KAP proteins and their genes in mammals, and to ascertain how these genes and proteins control fibre growth and characteristics. This effort is ongoing, with more and more being understood about the structure and function of the genes. This review consolidates that knowledge and suggests future directions for research to further our understanding.
The small heat shock protein, α-crystallin, exists in two isoforms, αA and αB, and displays strong ability against stress-induced apoptosis. Regarding their functional mechanisms, we and others have ...demonstrated that they are able to regulate members in both caspase and Bcl-2 families. In addition, we have also shown that αA and αB may display differential anti-apoptotic mechanisms under certain stress conditions. While αA-crystallin regulates activation of the AKT signaling pathway, αB negatively regulates the MAPK pathway to suppress apoptosis induced by UV and oxidative stress. Although previous studies revealed that αA and αB could regulate members in both caspase and Bcl-2 families, the molecular mechanism, especially the in vivo regulation still waits to be elucidated. In the present communication, we present both in vitro and in vivo evidence to further demonstrate the regulation of caspase-3 and Bax by αA and αB. First, Surface Plasmon Resonance (SPR) and yeast two-hybrid selection analysis demonstrate that αA and αB directly bind to caspase-3 and Bax with differential affinities. Second, immunohistochemistry reveals that αA and αB regulate caspase-3 and Bax at different developmental stages of mouse embryo. Third, coimmunoprecipitation shows that αA and αB form in vivo interacting complexes with caspase-3 and Bax. Together, our results further confirm that αA and αB regulate caspase-3 and Bax in vitro and in vivo to regulate lens differentiation.
CircRNA is a specific type of non-coding RNA that has been shown to have an important role in mammary gland (MG) activity, but no study of MG circRNA activity in sheep so far. In this study, the ...expression profile of circRNAs was investigated using RNA-Seq in MG parenchyma at peak lactation from Small-Tailed Han sheep and Gansu Alpine Merino sheep with phenotypic differences in milk yield and components. A total of 4, 906 circRNAs were found and 33 of these were differentially expressed between breeds. GO and KEGG results showed that the parental genes of differentially expressed circRNAs were mainly enriched in heterocyclic compound binding, kinase activity, adherens junction, the TGF-β signaling pathway, and the MAPK signaling pathway. This study provides an overview of circRNA expression in the ovine MG and the interaction between some key circRNAs and their target miRNAs. It improves our knowledge of the role of circRNA in sheep milk synthesis.
•The expression profile of circRNAs was investigated using RNA-Seq in ovine mammary gland of peak lactation.•A total of 4, 906 circRNAs were found and 33 of these were differentially expressed between breeds.•Parental genes of differentially expressed circRNAs were mainly enriched in some signaling pathways related to lactation.•Some target miRNAs of circRNAs were associated with mammary gland development and lactation.
Aims: Antibiotics from Bacillus subtilis JA show strong pathogen inhibition ability, which has potential market application; yet, the composition of these antibiotics has not been elucidated. The ...aim of this paper is to isolate and identify these antibiotics.
Methods and Results: The antagonistic activity of JA was tested in vitro; it exhibited strong inhibition against some important phytopathogens and postharvest pathogens. Crude antibiotic production was extracted with methanol from the precipitate by adding 6 mol l−1 HCl to the bacillus‐free culture broth. The crude extract was run on Diamonsil C18 column (5 μm, 250 × 4·6 mm) in HPLC system to separate the antibiotics. Major antibiotics were classified into three lipopeptide families according to electrospray ionization–mass spectrometry analysis. Subsequently, the classification of antibiotics was confirmed with typical collision‐induced dissociation fragments.
Conclusions: Three kinds of antibiotics were isolated from B. subtilis JA and were identified to the lipopeptide families, surfactin, iturin and fengycin. These compounds could function as biocontrol agents against a large spectrum of pathogens.
Significance and Impact of the Study: This study provided a reliable and rapid method for isolation and structural characterization of lipopeptide antibiotics from B. subtilis.
PurposeThis study establishes a method for predicting ground vibrations caused by railway tunnels in unsaturated soils with spatial variability.Design/methodology/approachFirst, an improved 2.5D ...finite-element-method-perfect-matching-layer (FEM-PML) model is proposed. The Galerkin method is used to derive the finite element expression in the ub-pl-pg format for unsaturated soil. Unlike the ub-v-w format, which has nine degrees of freedom per node, the ub-pl-pg format has only five degrees of freedom per node; this significantly enhances the calculation efficiency. The stretching function of the PML is adopted to handle the unlimited boundary domain. Additionally, the 2.5D FEM-PML model couples the tunnel, vehicle and track structures. Next, the spatial variability of the soil parameters is simulated by random fields using the Monte Carlo method. By incorporating random fields of soil parameters into the 2.5D FEM-PML model, the effect of soil spatial variability on ground vibrations is demonstrated using a case study.FindingsThe spatial variability of the soil parameters primarily affected the vibration acceleration amplitude but had a minor effect on its spatial distribution and attenuation over time. In addition, ground vibration acceleration was more affected by the spatial variability of the soil bulk modulus of compressibility than by that of saturation.Originality/valueUsing the 2.5D FEM-PML model in the ub-pl-pg format of unsaturated soil enhances the computational efficiency. On this basis, with the random fields established by Monte Carlo simulation, the model can calculate the reliability of soil dynamics, which was rarely considered by previous models.
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