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1.
Quant Imaging Med Surg ; 14(6): 4015-4030, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38846304

ABSTRACT

Background: Manual planning of scans in clinical magnetic resonance imaging (MRI) exhibits poor accuracy, lacks consistency, and is time-consuming. Meanwhile, classical automated scan plane positioning methods that rely on certain assumptions are not accurate or stable enough, and are computationally inefficient for practical application scenarios. This study aims to develop and evaluate an effective, reliable, and accurate deep learning-based framework that incorporates prior physical knowledge for automatic head scan plane positioning in MRI. Methods: A deep learning-based end-to-end automated scan plane positioning framework has been developed for MRI head scans. Our model takes a three-dimensional (3D) pre-scan image input, utilizing a cascaded 3D convolutional neural network to detect anatomical landmarks from coarse to fine. And then, with the determined landmarks, accurate scan plane localization can be achieved. A multi-scale spatial information fusion module was employed to aggregate high- and low-resolution features, combined with physically meaningful point regression loss (PRL) function and direction regression loss (DRL) function. Meanwhile, we simulate complex clinical scenarios to design data augmentation strategies. Results: Our proposed approach shows good performance on a clinically wide range of 229 MRI head scans, with a point-to-point absolute error (PAE) of 0.872 mm, a point-to-point relative error (PRE) of 0.10%, and an average angular error (AAE) of 0.502°, 0.381°, and 0.675° for the sagittal, transverse, and coronal planes, respectively. Conclusions: The proposed deep learning-based automated scan plane positioning shows high efficiency, accuracy and robustness when evaluated on varied clinical head MRI scans with differences in positioning, contrast, noise levels and pathologies.

2.
Article in English | MEDLINE | ID: mdl-38123967

ABSTRACT

BACKGROUND: To assess the applicability of the association between estimated glucose disposal rate (eGDR) and all-cause mortality in the elderly population, and the mediating role of brachial-ankle pulse wave velocity (baPWV). METHODS: This was a follow-up cohort study based on the cross-sectional survey of community-dwelling elderly. All participants in the study were included between September 2009 and June 2010, and the follow-up time was December 2020. Participants included 1862 Chinese community-dwelling elderly aged 60 years and above. Insulin resistance assessed by eGDR and arterial stiffness assessed by baPWV were the primary exposures of interest. Mortality, which was followed up until December 2020, was the primary outcome. Cox proportional hazards regression models were used to estimate the association of eGDR with mortality. The mediating effect of baPWV in this association was assessed by mediation analysis. RESULTS: A total of 1826 participants with a mean age of 71.03 years old were included in the study. During the median follow-up of 10.75 years, 334 participants died. The adjusted HR comparing the highest versus the lowest eGDR quartile was 0.22 (95% CI 0.09 to 0.54; p<0.001) in the Cox proportional hazards model. The results of mediation analysis showed that baPWV had a significant mediation impact on the link between eGDR and all-cause mortality both as continuous or categorical variables. CONCLUSION: eGDR is an independent predictor of all-cause mortality in the elderly population. baPWV partially mediated the association of eGDR and long-term all-cause mortality as a mediator factor.


Subject(s)
Ankle Brachial Index , Blood Glucose , Pulse Wave Analysis , Vascular Stiffness , Humans , Vascular Stiffness/physiology , Aged , Female , Male , Prospective Studies , Middle Aged , Blood Glucose/analysis , China/epidemiology , Cross-Sectional Studies , Follow-Up Studies , Insulin Resistance/physiology , Risk Factors , Proportional Hazards Models , Mortality , Aged, 80 and over , Independent Living
3.
J Phys Chem B ; 127(33): 7334-7341, 2023 Aug 24.
Article in English | MEDLINE | ID: mdl-37578858

ABSTRACT

The multi-scale supramolecular assembly (MSSA)-based extraction strategy with hydroxyl-functionalized ionic liquid (IL) is promising in the separation of metal ions from radioactive environments for which a comprehensive understanding toward the radiation stability of the MSSA system is necessary. Herein, we report on the analyses of the radiation stability of MSSA in extraction, especially the adopted ILs 1-(2-hydroxyethyl)-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (IL-1) and 1-(2-hydroxyethyl)-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl) imide (IL-2), by UV-vis, 1H NMR, and ESI-HRMS. It was found that the macroscopic assembly (MA) sphere could not be formed after γ irradiation on the extraction system with IL-1. On the contrary, the trisubstituted IL-2 instead of the disubstituted IL-1 remarkably improved the radiation stability of the MSSA system to guarantee the formation of the MA sphere. The high extraction efficiency could be kept, and the mechanism of such an improvement was revealed.

4.
Sci Rep ; 12(1): 7332, 2022 May 05.
Article in English | MEDLINE | ID: mdl-35513544

ABSTRACT

The accurate determination of fracture toughness (KIc) in rock is of great significance to the study of rock fracture characteristics. However, the effect of contact friction in the loading process on the test results of fracture toughness is rarely considered, and the tested KIc in previous studies is generally higher than the inherent KIc of the material. Based on the ABAQUS software, the influence of friction on the test results of KIc was investigated under different material elastic moduli, loading conditions and specimen sizes by the finite element analysis in this study. The results show that for the specimen with the notch semi-circular bend configuration, if the presence of friction is considered, the changes of load level, the span of roller support and the specimen size can significantly affect the test results of fracture toughness, except the elastic modulus of the material; if the influence of friction is not considered, there will be a large deviation in the research results of the size effect of fracture toughness in rock. As the friction coefficient increases, the estimated value of the fracture energy increases, while the fracture process zone length decreases for the specimen with an infinite size.

5.
PLoS One ; 11(8): e0160659, 2016.
Article in English | MEDLINE | ID: mdl-27501393

ABSTRACT

This study investigated the effects of rumen-protected methionine (RPM) and rumen-protected choline (RPC) on energy balance, postpartum lactation performance, antioxidant capacity and immune response in transition dairy cows. Forty-eight multiparous transition cows were matched and divided into four groups: control, 15 g/d RPC, 15 g/d RPM or 15 g/d RPC + 15 g/d RPM. Diet samples were collected daily before feeding, and blood samples were collected weekly from the jugular vein before morning feeding from 21 days prepartum to 21 days postpartum. Postpartum dry matter intake (DMI) was increased by both additives (P < 0.05), and energy balance values in supplemented cows were improved after parturition (P < 0.05). Both RPC and RPM decreased the plasma concentrations of non-esterified fatty acids (NEFA), ß-hydroxybutyric acid (BHBA), total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) (P < 0.05), but increased the plasma levels of glucose, very-low-density lipoprotein (VLDL) and apolipoprotein B100 (ApoB 100, P < 0.05). The supplements improved milk production (P < 0.05), and increased (P < 0.05) or tended to increase (0.05 < P < 0.10) the contents of milk fat and protein. The post-ruminal choline and methionine elevated the blood antioxidant status, as indicated by total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-Px) activity and the vitamin E concentration (P < 0.05), and reduced the plasma malondialdehyde (MDA) level (P < 0.05). Furthermore, RPM and RPC elevated the plasma interleukin 2 (IL-2) concentration and the CD4+/CD8+ T lymphocyte ratio in peripheral blood (P < 0.05). Alternatively, the levels of tumor necrosis factor-α (TNF-α) and IL-6 were decreased by RPM and RPC (P < 0.05). Overall, the regulatory responses of RPC and RPM were highly correlated with time and were more effective in the postpartum cows. The results demonstrated that dietary supplementation with RPC and RPM promoted energy balance by increasing postpartal DMI and regulating hepatic lipid metabolism, improved postpartum lactation performance and enhanced antioxidant capacity and immune function of transition dairy cows.


Subject(s)
Choline/metabolism , Dietary Supplements , Energy Metabolism/physiology , Homeostasis/physiology , Methionine/metabolism , Rumen/immunology , Rumen/metabolism , Animals , Antioxidants/metabolism , Cattle , Female , Lactation/physiology , Rumen/growth & development
6.
J Dairy Sci ; 97(4): 2281-90, 2014.
Article in English | MEDLINE | ID: mdl-24508430

ABSTRACT

The objective of this experiment was to characterize the relationship among rumen fermentation variables, milk fatty acid profile, and dietary physically effective neutral detergent fiber (peNDF) content in a study that controlled for the potential confounding effects of dissimilar dry matter intake among treatments. Ten multiparous Xinong Saanen dairy goats were divided into 2 groups with 2 ruminally cannulated goats per group. Goats in each group were assigned to 1 of 2 dietary treatments (high and low peNDF) according to a 2×2 crossover design with 2 periods. The peNDF content of alfalfa hay (proportion of neutral detergent fiber retained on an 8.0-mm screen) was 42.1% for the high-peNDF and 14.5% for the low-peNDF group. To ensure similar dry matter intake, each morning the amount of alfalfa hay consumed on the prior day by the high-peNDF group was determined (amount offered minus morning refusals), and this was the amount of hay offered to the low-peNDF group that day. Each adaptation period consisted of 21d, followed by a 9-d sampling period. Dry matter intake and milk production and composition were similar between treatments. Milk energy efficiency increased with low dietary peNDF. Duration of pH below 5.60 was longer for goats fed the low-peNDF ration compared with the high-peNDF ration (4.08 vs. 0.41h/d); however, mean rumen pH (6.05 vs. 6.13) was not different between treatments. Reducing dietary peNDF increased rumen total volatile fatty acids (114.6 vs. 95.1mM) and decreased chewing time (404 vs. 673min/d), but did not affect the ratios of acetate, propionate, and butyrate. The relative abundance of Fibrobacter succinogenes and Ruminococcus flavefaciens increased with reduced dietary peNDF, but Ruminococcus albus proportions were not influenced by treatment. Reducing dietary peNDF decreased the proportion of iso C14:0, iso C15:0, and trans-11 C18:1 in milk fat, whereas the iso C17:0 and trans-10 C18:1 increased. This study demonstrated that low dietary peNDF in dairy goats increases rumen volatile fatty acids, reduces chewing time, and is correlated to the amount of F. succinogenes and R. flavefaciens.


Subject(s)
Diet/veterinary , Dietary Fiber/administration & dosage , Fatty Acids, Volatile/analysis , Fermentation , Milk/chemistry , Rumen/physiology , Animal Feed , Animals , Female , Goats , Hydrogen-Ion Concentration , Mastication , Particle Size , Rumen/microbiology
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