Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
LanguageLanguage
-
SubjectSubject
-
Item TypeItem Type
-
DisciplineDiscipline
-
YearFrom:-To:
-
More FiltersMore FiltersIs Peer Reviewed
Done
Filters
Reset
26,571
result(s) for
"Yan, Yuan"
Sort by:
Two-billion-year-old volcanism on the Moon from Chang’e-5 basalts
2021
The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets
1
. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9–2.8 billion years ago (Ga)
2
,
3
, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration
4
,
5
. Here we report a precise lead–lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang’e-5 mission, and a
238
U/
204
Pb ratio (
µ
value)
6
of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800–900 million years. The
µ
value of the Chang’e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (
µ
value of about 300–1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts
7
(
µ
value of about 2,600–3,700), indicating that the Chang’e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.
Basalt samples returned from the Moon by the Chang’e-5 mission are revealed to be two billion years old by radioisotopic dating, providing insight on the volcanic history of the Moon.
Journal Article
Clinical characteristics of patients with 2019 coronavirus disease in a non-Wuhan area of Hubei Province, China: a retrospective study
by
Xu, Xuan-Xuan
,
Zhao, Xin-Ying
,
Tang, Yuan-Yan
in
Adult
,
Aspartate
,
Aspartate aminotransferase
2020
Background
Since December 2019, the 2019 coronavirus disease (COVID-19) has expanded to cause a worldwide outbreak that more than 600,000 people infected and tens of thousands died. To date, the clinical characteristics of COVID-19 patients in the non-Wuhan areas of Hubei Province in China have not been described.
Methods
We retrospectively analyzed the clinical characteristics and treatment progress of 91 patients diagnosed with COVID-19 in Jingzhou Central Hospital.
Results
Of the 91 patients diagnosed with COVID-19, 30 cases (33.0%) were severe and two patients (2.2%) died. The severe disease group tended to be older (50.5 vs. 42.0 years;
p
= 0.049) and have more chronic disease (40% vs. 14.8%;
p
= 0.009) relative to mild disease group. Only 73.6% of the patients were quantitative polymerase chain reaction (qPCR)-positive on their first tests, while typical chest computed tomography images were obtained for each patient. The most common complaints were cough (
n
= 75; 82.4%), fever (
n
= 59; 64.8%), fatigue (
n
= 35; 38.5%), and diarrhea (
n
= 14; 15.4%). Non-respiratory injury was identified by elevated levels of aspartate aminotransferase (
n
= 18; 19.8%), creatinine (
n
= 5; 5.5%), and creatine kinase (
n
= 14; 15.4%) in laboratory tests. Twenty-eight cases (30.8%) suffered non-respiratory injury, including 50% of the critically ill patients and 21.3% of the mild patients.
Conclusions
Overall, the mortality rate of patients in Jingzhou was lower than that of Wuhan. Importantly, we found liver, kidney, digestive tract, and heart injuries in COVID-19 cases besides respiratory problems. Combining chest computed tomography images with the qPCR analysis of throat swab samples can improve the accuracy of COVID-19 diagnosis.
Journal Article
The study of the separation and deposition of dredging soil slurry under physical disturbance
2023
Most existing research uses experimental designs for testing, which cannot efficiently analyse the migration and sorting rules of particles in the disturbed slurry. Therefore, based on the fluidized bed flow film theory, a slurry flow film structure system is established according to the disturbance state of the fluid. On this basis, the particle size and distribution law of the disturbing force formed by slurry disturbance are analyzed, and the calculation model of single particle lift in the flowing film is also analyzed. On this basis, using Markov probability model, the probability of particle lifting and sorting between layers is theoretically deduced. Then, according to the particle ratio of the original mud, the settlement gradation of the particles in the disturbance is analyzed. It can also predict the separation degree of particle in natural turbulence, fluidized beds, and sludge mechanical dewatering. Finally, according to the particle flow software PFC (Particle Flow Code), the main influencing parameters (disturbing force and gradation) were verified and analyzed. The results show that the particle flow simulation results are in good agreement with the calculation results. The model of slurry membrane separation proposed in this paper can provide a basis for studying the mechanism of slurry disturbance separation and particle deposition.
Journal Article
Ferroptosis: a cell death connecting oxidative stress, inflammation and cardiovascular diseases
2021
Ferroptosis, a recently identified and iron-dependent cell death, differs from other cell death such as apoptosis, necroptosis, pyroptosis, and autophagy-dependent cell death. This form of cell death does not exhibit typical morphological and biochemical characteristics, including cell shrinkage, mitochondrial fragmentation, nuclear condensation. The dysfunction of lipid peroxide clearance, the presence of redox-active iron as well as oxidation of polyunsaturated fatty acid (PUFA)-containing phospholipids are three essential features of ferroptosis. Iron metabolism and lipid peroxidation signaling are increasingly recognized as central mediators of ferroptosis. Ferroptosis plays an important role in the regulation of oxidative stress and inflammatory responses. Accumulating evidence suggests that ferroptosis is implicated in a variety of cardiovascular diseases such as atherosclerosis, stroke, ischemia-reperfusion injury, and heart failure, indicating that targeting ferroptosis will present a novel therapeutic approach against cardiovascular diseases. Here, we provide an overview of the features, process, function, and mechanisms of ferroptosis, and its increasingly connected relevance to oxidative stress, inflammation, and cardiovascular diseases.
Journal Article
Root Damage under Alkaline Stress Is Associated with Reactive Oxygen Species Accumulation in Rice (Oryza sativa L.)
by
Liang, Zheng-Wei
,
Zhang, Hui
,
Zhang, Rui-Xue
in
Abiotic stress
,
Accumulation
,
alkaline stress
2017
Alkaline stress (high pH) severely damages root cells, and consequently, inhibits rice (
L.) seedling growth. In this study, we demonstrate the accumulation of reactive oxygen species (ROS) in root cells under alkaline stress. Seedlings of two rice cultivars with different alkaline tolerances, 'Dongdao-4' (moderately alkaline-tolerant) and 'Jiudao-51' (alkaline-sensitive), were subjected to alkaline stress simulated by 15 mM sodium carbonate (Na
CO
). Alkaline stress greatly reduced seedling survival rate, shoot and root growth, and root vigor. Moreover, severe root cell damage was observed under alkaline stress, as shown by increased membrane injury, malondialdehyde accumulation, and Evan's Blue staining. The expression of the cell death-related genes
,
,
, and
was consistently upregulated, while that of a cell death-suppressor gene,
, was downregulated. Analysis of the ROS contents revealed that alkaline stress induced a marked accumulation of superoxide anions ([Formula: see text]) and hydrogen peroxide (H
O
) in rice roots. The application of procyanidins (a potent antioxidant) to rice seedlings 24 h prior to alkaline treatment significantly alleviated alkalinity-induced root damage and promoted seedling growth inhibition, which were concomitant with reduced ROS accumulation. These results suggest that root cell damage, and consequently growth inhibition, of rice seedlings under alkaline stress is closely associated with ROS accumulation. The antioxidant activity of superoxide dismutase, catalase, peroxidase, and ascorbate peroxidase increased under alkaline stress in the roots, probably in response to the cellular damage induced by oxidative stress. However, this response mechanism may be overwhelmed by the excess ROS accumulation observed under stress, resulting in oxidative damage to root cells. Our findings provide physiological insights into the molecular mechanisms of alkalinity-induced damage to root cells, and will contribute to the improvement of alkaline stress tolerance in rice plants.
Journal Article
The efficacy and safety of neoadjuvant and adjuvant chemo(radio)therapy combined with surgery in patients with locally advanced rectal cancer harboring defective mismatch repair system: a large-scale multicenter propensity score analysis
2025
For locally advanced rectal cancer (LARC) with a deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H), particularly in patients not eligible for immunotherapy, the optimal treatment remains undetermined. This study was to evaluate the efficacy and safety of surgery, surgery and chemotherapy, surgery and chemoradiotherapy, in patients with LARC harboring dMMR/MSI-H.
Patients included from three university centers between August 1, 2012 and March 1, 2023, were categorized into three treatment groups: surgery
. surgery + chemotherapy
. surgery + chemoradiotherapy. The primary endpoint was overall survival (OS), with secondary endpoints of progression-free survival (PFS), local recurrence (LR), distant metastasis (DM), and toxicity. The Kaplan-Meier method was utilized to analyze OS and PFS; competing risk methods were employed to evaluate rates of LR and DM. Adjustments were performed utilizing inverse probability of treatment weighting (IPTW) and overlap weighting (OW) based on propensity score, employing logistic regression model. The Cox proportional hazards model was applied for both univariate and multivariate analyses to assess prognostic factors influencing patient OS and PFS.
A total of 119 patients were included, with 45 patients (37.8%) receiving surgery alone, 32 (26.9%) receiving surgery + chemotherapy, and 42 (35.3%) undergoing surgery + chemoradiotherapy. In both the unadjusted cohort and after IPTW and OW adjustments, the surgery alone group (
. surgery + chemoradiotherapy) had improved OS, PFS, LR, but no significant differences in DM. However, no statistical difference was found between the surgery
. surgery + chemotherapy groups in OS, PFS, and DM, except for significant differences in LR. Similar results were found in both neoadjuvant and adjuvant treatment cohorts. No adverse events of grade 5 occurred.
This study suggests surgery alone (without chemotherapy and/or radiotherapy) may be an optimal treatment for LARC patients with dMMR/MSI-H, particularly in those who cannot tolerate or access immunotherapy. The results of this study may be used to power a randomized trial for the approaches.
Journal Article
Effects of high-fidelity simulation teaching on nursing students' knowledge, professional skills and clinical ability: A meta-analysis and systematic review
by
Lei, Yan-Yuan
,
Cui, Xiang-Shu
,
Sa, Ya Tuo Ren
in
Ability
,
Clinical Competence
,
Clinical decision making
2022
This meta-analysis was designed to systematically determine the effect of high-fidelity simulation teaching on nursing students' knowledge level, professional skill level and clinical ability.
High-fidelity simulation is an increasingly popular pedagogical approach in nursing education. It provides students with opportunity to practice in a variety of simulations before entering clinical practice through a variety of real-life situational experiences and many institutions and educators have embraced this method for enhancing access to clinical skills. However, evidence for the effectiveness of the method in nursing teaching remains scarce.
A meta-analysis and systematic review.
The following Chinese and English databases were searched for relevant articles: PubMed, Embase, Cochrane library, Web of Science, CNKI (China National Knowledge Infrastructure) and Wangfang. The search encompassed the establishment of these databases up until November 2021. Two reviewers separately entered the data into Review Manager Software 5.3.
A total of 15 studies were included in this study. High-fidelity simulation significantly increased nursing students’ knowledge acquisition (SMD = 1. 37, 94%CI:0. 73–2. 00,P <0. 0001), enhanced nursing students’professional skills (SMD = 0. 90, 95%CI:0. 36–1. 44,P = 0. 0001). In terms of clinical practice ability outcomes, high-fidelity simulation significantly improved the levels of critical thinking ability (SMD = 0. 58, 95%CI:0. 09–1. 07,P <0. 00001), Clinical judgement ability (SMD = 1. 34, 95%CI:0. 38–2. 31,P=0. 006) and communication skills (SMD = 2. 62, 95%CI:1. 84–3. 40,P <0. 001) of nursing students.
We found that high-fidelity simulation have strong educational effects in nursing education, helping nursing students to increase knowledge acquisition, enhance professional skills and cultivate their clinical practice ability (critical thinking ability, communication skills and clinical judgement ability). These findings can provide guidance for nursing educators, indicating that the use of High-fidelity simulation teaching represents an effective solution for transitioning students from the learning environment to clinical practice.
Journal Article
Mechanical analysis of eight-legged temporary support structure under wave forces
by
Yuan, Yan-zhao
,
Wang, Weikuan
in
Analysis
,
Buildings and facilities
,
Computer and Information Sciences
2023
This paper presents a mechanical analysis of the foundation of a temporary offshore platform using a temporary embedded eight-leg support structure. The model is simulated using the finite element simulation software MIDAS-3D, with the modified RANS equation and Forchheimer saturated resistance model used to control the fluid. The stress analysis principle of the structure is simplified by the pile group theory. The stability of the eight-legged supporting structure is investigated under different embedding depths, pile diameters, wave periods, and amplitudes of the main piles. The results show that the eight-legged supporting structure can intercept and divert water flow, eliminating the impact of the water flow on the main piles during large waves. Additionally, as the diameter of the structure increases under the same wave conditions, the influence of the base volume and surface curvature gradually increases, deteriorating the stress environment of the main pile and decreasing the supporting effect of the eight-legged support structure. Numerical calculations of the seabed rock foundation of the eight-leg supporting structure show that the shallow pile foundation undergoes significant deformation, while the eight-leg supporting structure is still supported by the dead weight of the main pile.
Journal Article
Catalytic polymer self-cleavage for CO2 generation before combustion empowers materials with fire safety
2024
Polymeric materials, rich in carbon, hydrogen, and oxygen elements, present substantial fire hazards to both human life and property due to their intrinsic flammability. Overcoming this challenge in the absence of any flame-retardant elements is a daunting task. Herein, we introduce an innovative strategy employing catalytic polymer auto-pyrolysis before combustion to proactively release CO
2
, akin to possessing responsive CO
2
fire extinguishing mechanisms. We demonstrate that potassium salts with strong nucleophilicity (such as potassium formate/malate) can transform conventional polyurethane foam into materials with fire safety through rearrangement. This transformation results in the rapid generation of a substantial volume of CO
2
, occurring before the onset of intense decomposition, effectively extinguishing fires. The inclusion of just 1.05 wt% potassium formate can significantly raise the limiting oxygen index of polyurethane foam to 26.5%, increase the time to ignition by 927%, and tremendously reduce smoke toxicity by 95%. The successful application of various potassium salts, combined with a comprehensive examination of the underlying mechanisms, underscores the viability of this strategy. This pioneering catalytic approach paves the way for the efficient and eco-friendly development of polymeric materials with fire safety.
Overcoming this challenge of fire hazards by carbon, hydrogen, and oxygen rich materials remains challenging. Here, the authors demonstarte that catalytic polymer auto-pyrolysis before combustion releases CO2, equipping the material with fire retardant properties.
Journal Article
Transcriptome Analysis of the Brown Planthopper Nilaparvata lugens
2010
The brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the most serious insect pests of rice in Asia. However, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. Genomic information for BPH is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of BPH.
In this study, we performed de novo transcriptome assembly and gene expression analysis using short-read sequencing technology (Illumina) combined with a tag-based digital gene expression (DGE) system. The transcriptome analysis assembles the gene information for different developmental stages, sexes and wing forms of BPH. In addition, we constructed six DGE libraries: eggs, second instar nymphs, fifth instar nymphs, brachypterous female adults, macropterous female adults and macropterous male adults. Illumina sequencing revealed 85,526 unigenes, including 13,102 clusters and 72,424 singletons. Transcriptome sequences larger than 350 bp were subjected to Gene Orthology (GO) and KEGG Orthology (KO) annotations. To analyze the DGE profiling, we mainly compared the gene expression variations between eggs and second instar nymphs; second and fifth instar nymphs; fifth instar nymphs and three types of adults; brachypterous and macropterous female adults as well as macropterous female and male adults. Thousands of genes showed significantly different expression levels based on the various comparisons. And we randomly selected some genes to confirm their altered expression levels by quantitative real-time PCR (qRT-PCR).
The obtained BPH transcriptome and DGE profiling data provide comprehensive gene expression information at the transcriptional level that could facilitate our understanding of the molecular mechanisms from various physiological aspects including development, wing dimorphism and sex difference in BPH.
Journal Article