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1.
Nanotechnology ; 32(1): 015707, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916664

RESUMO

In order to overcome the drawbacks of Fe3O4 composite samples and greatly increase their performance in microwave absorption, magnetic Fe3O4 spindles coated with dielectric SnO2 nanorods and MnO2 nanoflakes have been successfully synthesized by a four-step simple hydrothermal route. This rationally designed magneto-dielectric ternary nanocomposite will introduce multiple reflection and conductive losses caused by its special multilayer structure and the effective complementarity of dielectric loss and magnetic loss. Therefore, its absorbing performance can be greatly improved. It is notable that the as-prepared Fe3O4@SnO2@MnO2 nanocomposites show a minimum reflection loss value of -50.40 dB at 17.92 GHz at a thickness of 3.9 mm and the absorption bandwidth ranges from 3.62 to 12.08 GHz. The as-prepared Fe3O4@SnO2@MnO2 ternary nanocomposite is expected to be a potential candidate for high-performance microwave-absorbing materials with intensive electromagnetic wave absorption and wide effective absorbing bandwidth.

2.
J Dairy Sci ; 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33041031

RESUMO

Ruminal pH is a critical factor to regulate nutrient degradation and fermentation. However, it has been poorly predicted in the Molly cow model, and recent improvements in the representation of nitrogen cycling across the rumen wall altered some of the modeled responses to feed nutrients, resulting in some model bias. The objectives of this study were to further improve the representation of pH and to refit parameters related to ruminal metabolism and nutrient digestion in the model to resolve this bias, and to use the improved model to estimate nitrogen and energy fluxes with varying rumen-degradable protein (RDP; 40 vs. 60%) and ruminally degraded starch (RDSt; 50 vs. 75%). A meta data set containing 284 peer reviewed studies with 1,223 treatment means was used to derive parameter estimates for ruminal metabolism and nutrient digestions. Refitting the parameters significantly improved the accuracy and precision of the model predictions for ruminal nutrient outflow [acid detergent fiber (ADF), neutral detergent fiber (NDF), total N, microbial N, nonammonia N, and nonammonia nonmicrobial N], ammonia and blood urea concentrations, and fecal nutrient outflow (protein, ADF, and NDF). The prediction error for body weight was decreased from 19.3 to 6.2% with decreased mean bias (from 76.0 to 11.5%) and slope bias (from 17.2 to 7.7%), primarily due to improved representations of ruminal dry matter and liquid pool size. Adding ammonia concentration as a driver to the pH equation increased the precision of predicted ruminal pH and, thereby, the precision of predicted volatile fatty acid (VFA) concentrations, due to improved representation of pH regulation of VFA production rates. Although minor mean and slope bias were observed for ruminal pH and VFA concentrations, the concordance correlation coefficients indicated that much of the observed variation in these variables remains unexplained. Overall, the biological functions of nutrient degradation and digestion appear to be represented without bias. Simulated results indicated that decreasing RDP and RDSt proportions in an isonitrogenous and isocaloric diet can slightly improve N efficiency, and increasing RDSt proportions can increase energy efficiency.

3.
Cell Death Differ ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037394

RESUMO

Dysregulation of the balance between cell proliferation and cell death is a central feature of malignances. Death-associated protein kinase 3 (DAPK3) regulates programmed cell death including apoptosis and autophagy. Our previous study showed that DAPK3 downregulation was detected in more than half of gastric cancers (GCs), which was related to tumor invasion, metastasis, and poor prognosis. However, the precise molecular mechanism underlying DAPK3-mediated tumor suppression remains unclear. Here, we showed that the tumor suppressive function of DAPK3 was dependent on autophagy process. Mass spectrometry, in vitro kinase assay, and immunoprecipitation revealed that DAPK3 increased ULK1 activity by direct ULK1 phosphorylation at Ser556. ULK1 phosphorylation by DAPK3 facilitates the ULK1 complex formation, the VPS34 complex activation, and autophagy induction upon starvation. The kinase activity of DAPK3 and ULK1 Ser556 phosphorylation were required for DAPK3-modulated tumor suppression. The coordinate expression of DAPK3 with ULK1 Ser556 phosphorylation was confirmed in clinical GC samples, and this co-expression was correlated with favorable survival outcomes in patients. Collectively, these findings indicate that the tumor-suppressor roles of DAPK3 in GC are associated with autophagy and that DAPK3 is a novel autophagy regulator, which can directly phosphorylate ULK1 and activate ULK1. Thus, DAPK3 might be a promising prognostic autophagy-associated marker.

4.
Lasers Med Sci ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037559

RESUMO

The meta-analysis aimed to systematically evaluate all the available pieces of evidence concerning the clinical effectiveness of Er,Cr:YSGG lasers (erbium, chromium, yttrium scandium gallium garnet laser) in the non-surgical treatment of patients with chronic periodontitis, and provide guidance for clinicians about the application of Er,Cr:YSGG lasers during the process of non-surgical periodontal treatments. The meta-analysis was conducted with data extracted from 16 randomized controlled clinical trials (RCTs) that compare Er,Cr:YSGG lasers adjunct/substitute to scaling and root planing (SRP) with SRP alone for the treatment of chronic periodontitis published in English or Chinese from January 2000 to January 2020. The weighted mean differences (WMDs) and 95% confidence intervals (CIs) were counted for probing depth (PD) reduction, clinical attachment level (CAL) gain, and visual analogue scale (VAS) score. Heterogeneity of each study was evaluated with the Q test. The publication bias was measured using Begg's adjusted rank correlation test. Sixteen RCTs with 606 patients were included in the meta-analysis. There were statistically significant differences between Er,Cr:YSGG lasers adjunct/substitute to SRP and SRP alone in the PD reduction at 1-month follow-up (WMD = ­ 0.35, 95% CI [- 0.63, ­ 0.07], P = 0.013), 3-month follow-up (WMD = - 0.342, 95% CI [- 0.552, - 0.132], P = 0.001), CAL gain at 3-month follow-up (WMD = - 0.17, 95% CI [- 0.31, 0.03], P = 0.017), and VAS score (WMD = - 2.395, 95% CI [- 3.327, - 1.464], P = 0.000) immediately after treatment. There were no significant differences of PD reduction and CAL change at 6-month follow-up. The present meta-analysis indicated that Er,Cr:YSGG lasers provided additional effectiveness in PD reduction and CAL gain at short-term follow-ups and there was less pain compared with SRP alone.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33048677

RESUMO

The images used in various practices are often disturbed by noise, such as Gaussian noise, speckled noise, and salt and pepper noise. Images with noise are one of the challenges for segmentation, since the noise may cause inaccurate segmented results. To cope with the effect of noise on images during segmentation, a novel active contour model is proposed in this paper. The newly proposed model consists of fitting term, regularization term and penalty term. The fitting term is designed using a Gaussian kernel function and fractional order differentiation with an adaptively defined fractional order, which applies different orders to different pixels. The regularization term is applied to maintain the smoothness of curves. In order to ensure stable evolution of curves, a penalty term is added into the proposed model. Comparison experiments are conducted to show the effectiveness and efficiency of the proposed model.

6.
Exp Eye Res ; : 108282, 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33049272

RESUMO

Posterior capsule opacification (PCO) after cataract surgery is one of the leading causes of visual impairment and blindness. The cause of PCO is the capsule fibrosis developed on implanted Intraocular Lens (IOLs) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing epithelial mesenchymal transition. How to prevent PCO has been a challenge to scientists and ophthalmologists for decades. Here we demonstrated the use of carboxylated CuInS/ZnS quantum dots (ZCIS QDs), which are free of toxic heavy metals and are more biocompatible, as photothermal nanomedicines. The ZCIS QDs are modified onto the non-optical section of IOLs by a facial activation-immersion method. Under mild NIR laser irradiation, ZCIS QDs modified IOLs (QDs-IOLs) will generate localized heat and prevent the proliferation of LECs onto the surface of QDs-IOLs. Our findings provide experimental evidence for further application of combined nanotechnology and photothermal therapy for the clinical treatment of PCO.

7.
Transfus Med ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33000534

RESUMO

OBJECTIVE: The COVID-19 epidemic has caused a significant global social and economic impact since December 2019. The objective of this study was to demonstrate the emergency response of a Chinese blood centre on maintaining both the safety and the sufficiency of blood supply during large, emerging, infectious epidemics. MATERIALS AND METHODS: Early on in the outbreak of COVID-19, the Chengdu Blood Center developed strategies and implemented a series of measures, including enhanced recruitment efforts, addition of new donation deferral criteria and notification after donation, optimisation of donor experience, development and implementation of a new coronavirus nucleic acid detection technology platform for blood screening and screening all donations for SARS-CoV-2 RNA to maximumly protect the safety of blood supply during a time of unclear risk. RESULTS: Starting on February 20, the immediate satisfaction rate of blood product orders in Chengdu city's clinical settings reached 100%, and there was no case of blood transfusion infection. CONCLUSION: The recent experience during the outbreak of SARS-CoV-2 reminded us that improvement in the areas of national and international collaborative programmes for dealing with blood availability and safety concerns during early stages of a disaster and regional and national mechanisms for timely communication with the general public on behalf of blood services should help to better prepare us for future disasters.

8.
Sci Rep ; 10(1): 16585, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024198

RESUMO

In recent years, most biofilm studies have focused on fundamental investigations using multispecies biofilm models developed preferentially in simulated naturally occurring low-nutrient medium than in artificial nutrient-rich medium. Because biofilm development under low-nutrient growth media is slow, natural media are often supplemented with an additional carbon source to increase the rate of biofilm formation. However, there are knowledge gaps in interpreting the effects of such supplementation on the resulting biofilm in terms of structure and microbial community composition. We investigated the effects of supplementation of a simulated freshwater medium with sodium citrate on the resulting structure, bacterial community composition, and microbial network interactions of an early-stage multispecies biofilm model. Qualitative and quantitative analyses of acquired confocal laser scanning microscopy data confirmed that sodium citrate supplementation distinctly increased biofilm biomass. Sequencing data revealed that the microbial community structure of biofilms grown in sodium citrate-supplemented conditions was characterized with increased relative abundance and dominance of Proteobacteria compared with that of biofilms grown in sodium citrate-free conditions. Our findings suggest that the supplementation of a low-nutrient medium with a carbon source in experiments involving multispecies biofilms may lead to structural and compositional biases of the microbial community, causing changes in biofilm phenotype.

9.
Ann Neurol ; 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-33016348

RESUMO

NOTCH2NLC GGC repeat expansions were recently identified in neuronal intranuclear inclusion disease (NIID); however, it remains unclear whether they occur in other neurodegenerative disorders. This study aimed to investigate the role of intermediate-length NOTCH2NLC GGC repeat expansions in Parkinson disease (PD). We screened for GGC repeat expansions in a cohort of 1,011 PD patients and identified 11 patients with intermediate-length repeat expansions ranging from 41 to 52 repeats, with no repeat expansions in 1,134 controls. Skin biopsy revealed phospho-alpha-synuclein deposition, confirming the PD diagnosis in 2 patients harboring intermediate-length repeat expansions instead of NIID or essential tremor. Fibroblasts from PD patients harboring intermediate-length repeat expansions revealed NOTCH2NLC upregulation and autophagic dysfunction. Our results suggest that intermediate-length repeat expansions in NOTCH2NLC are potentially associated with PD. ANN NEUROL 2020.

10.
Phys Chem Chem Phys ; 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33020795

RESUMO

Recently, a new class of lithium chlorides and bromides (e.g., Li3YCl6 and Li3YBr6) were reported to be promising solid-state electrolytes with high ionic conductivity in all-solid-state battery cells. However, their response under mechanical loading is not known which is critical as mechanical properties can play a pivotal role in reducing interfacing resistance between electrolytes and electrodes. To address this issue, herein, we report the thermo-physical properties of these lithium chlorides and bromides using density functional theory calculations. It was found that the new structures possess relatively larger shear moduli than those of thio-phosphate-type solid-state electrolytes and smaller Young's moduli than those of Garnet-type solid-state electrolytes. This suggests that the new halide materials can be more effective in suppressing the formation of lithium dendrites, accommodating volumetric changes of electrode materials and preventing their own degradation. Meanwhile, Poisson's ratio and Pugh's indicator calculations showed that Li3YCl6 and Li3ScCl6 possess improved ductility than other halide candidates, and thus hold promise as solid-state electrolytes. On the other hand, owing to their relatively high thermal conductivities, lithium bromides were found to be more advantageous in conducting heat which is important to ensure safety. These results provide fundamental insights into the mechanical properties of lithium chlorides and bromides and contribute to the rational mechanical design of solid-state electrolytes and the development advanced all-solid-state batteries.

11.
J Cancer Res Ther ; 16(5): 1106-1111, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33004755

RESUMO

Background: Even with the use of contrast-enhanced thin-layer chest computed tomography (CT) and endoscopic ultrasonography (EUS), the likelihood of cT2N0M0 squamous cell esophageal cancer correlating with the final pathologic outcome is exceedingly low. We therefore sought to investigate the associations between different risk factors and pathologic upstaging in stage T2N0M0 esophageal cancer patients who underwent esophagectomy. Materials and Methods: We retrospectively reviewed the clinicopathological characteristics of 224 stage T2N0M0 squamous cell esophageal cancer patients who underwent complete resection over a 2-year period (October 2016-September 2018). The tumor volume (TV) was automatically measured from thin-layer chest CT scans using imaging software. Univariate and multivariate analyses were performed to identify the risk factors associated with upstaging. A receiver operating characteristic (ROC) curve was plotted, and its ability to identify pathological upstaging was assessed. Results: A total of 224 patients with clinical stage T2N0M0 squamous cell esophageal carcinoma (SCEC) underwent esophagectomy; of these patients, 96 (42.86%) had a more advanced stage during the final pathologic review than during the initial diagnosis. The risk factors for pathologic upstaging included a large TV, high total cholesterol (TC), high triglycerides (TGs), high platelet-to-lymphocyte ratio (PLR), and high number of lymph nodes examined. The ROC analysis demonstrated an area under the curve of 0.845 (95% confidence interval 0.794-0.895). Conclusions: In SECC diagnosed as stage T2N0M0 by CT and EUS, the incidence of postoperative pathologic upstaging increases with a large TV, high TC, high TGs, high PLR, and high number of lymph nodes examined.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(5): 1774-1781, 2020 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-33067989

RESUMO

OBJECTIVE: To investigate the clinical significance of post-transplantation serum immunoglobulin level in the outcome of patients with hemalologic malignancies treated by haploidentical peripheral hematopoietic stem cell transplanta-tion(Haplo-HSCT). METHODS: The clinical data of 157 patients treated by haplo-HSCT were analyzed retrospectively. The overall survival rate (OS), graft versus host disease (GVHD) incidence, infection incidence, serum immunoglobulin level, the relationship of immunoglobulin levels with OS and transplant complications were analyzed. RESULTS: The 2-year OS rate was 59.2%(95%CI:51.6%-66.9%), 2-year relapse mortality was 11.5%(95%CI: 6.4%-16.6%), and non-relapse mortality was 29.3%(95%CI:21.7%-36.9%). The cumulative incidence of III-IV aGVHD was 16.6%(95%CI:10.8%-22.9%); the cumulative incidence of extensive cGVHD was 21.7%(95%CI:15.3%-28.6%); the cumulative incidence of severe bacterial infection within 1 year was 59.2%(95%CI:51.6%-66.2%); the cumulative incidence of invasive fungal infection was 47.1%(95%CI:38.9%-54.8%). The occurrence of extensive cGVHD after haplo-HSCT related with the gender match of donor-recipient and bacterial infection. The levels of IgG in patients with 0-II aGVHD and patients with III-IV aGVHD for 1 month after haplo-HSCT were (6.96±2.47) and (4.27±2.42) g/L (P=0.003), IgG levels at 3 months afte haplo-HSCT were (8.71±4.47) and (6.65±2.95) g/L (P=0.038); IgG levels at 1 month after haplo-HSCT showed predictive value for III-IV aGVHD susceptibility(P=0.003); for patients with IgG<4 g/L at any time after haplo-HSCT, the incidence of extensive cGVHD was significantly increased (35.5% vs 18.3%) (P=0.037), the incidence of fungal infection within 1 year after haplo-HSCT was significantly increased(71.0% vs 41.3%) (P=0.003), and the 2-year survival rate was reduced significantly (P=0.035). CONCLUSION: Haplo-HSCT is effective for the treatment of hematologic malignancies. Patients with lower IgG at 1 month after haplo-HSCT are more likely to develop III-IV aGVHD, and IgG levels at 1 month after haplo-HSCT can predict its susceptibility to a certain extent. Patients with severe hypoimmunoglobulinemia (IgG<4 g/L) after haplo-HSCT are more likely to develop extensive cGVHD, fungal infection and show worse survival prognosis.


Assuntos
Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Neoplasias Hematológicas/terapia , Humanos , Imunoglobulinas , Recidiva Local de Neoplasia , Estudos Retrospectivos
13.
Environ Sci Technol ; 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33081467

RESUMO

Both Fe(III) and fatty acids are ubiquitous and important species in environmental waters. Because they are amphipathic, many fatty acids are surface active and prone to enrichment at the air-water interface. Here, we report that by using nonanoic acid (NA) as a model fatty acid, coexisting Fe(III), even at concentrations as low as 1 µM, markedly enhanced the photochemical release of NA-derived volatile organic compounds (VOCs) such as octanal and octane into the air. Further studies indicated that the surface-enriched fatty acids dramatically increase the local concentration of Fe(III) at the water surface, which enables Fe(III)-mediated photochemical reactions to take place at the air-water interface, and the VOCs facilely produced by fatty acid photooxidation can then be released into the air. Moreover, the product distribution in the Fe(III)-mediated reactions was largely different from that in other photochemical systems, and a mechanism based on photochemical decarboxylation is proposed. Considering that the coexistence of fatty acids and Fe(III) in the environment is common, the enhanced photochemical release of VOCs by surface-enriched fatty acids and Fe(III) may be an important channel for the atmospheric emission of VOCs, which are known to play an essential role in the formation of ozone and secondary organic aerosols.

14.
Hortic Res ; 7: 165, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082971

RESUMO

Cerasus serrulata is a flowering cherry germplasm resource for ornamental purposes. In this work, we present a de novo chromosome-scale genome assembly of C. serrulata by the use of Nanopore and Hi-C sequencing technologies. The assembled C. serrulata genome is 265.40 Mb across 304 contigs and 67 scaffolds, with a contig N50 of 1.56 Mb and a scaffold N50 of 31.12 Mb. It contains 29,094 coding genes, 27,611 (94.90%) of which are annotated in at least one functional database. Synteny analysis indicated that C. serrulata and C. avium have 333 syntenic blocks composed of 14,072 genes. Blocks on chromosome 01 of C. serrulata are distributed on all chromosomes of C. avium, implying that chromosome 01 is the most ancient or active of the chromosomes. The comparative genomic analysis confirmed that C. serrulata has 740 expanded gene families, 1031 contracted gene families, and 228 rapidly evolving gene families. By the use of 656 single-copy orthologs, a phylogenetic tree composed of 10 species was constructed. The present C. serrulata species diverged from Prunus yedoensis ~17.34 million years ago (Mya), while the divergence of C. serrulata and C. avium was estimated to have occurred ∼21.44 Mya. In addition, a total of 148 MADS-box family gene members were identified in C. serrulata, accompanying the loss of the AGL32 subfamily and the expansion of the SVP subfamily. The MYB and WRKY gene families comprising 372 and 66 genes could be divided into seven and eight subfamilies in C. serrulata, respectively, based on clustering analysis. Nine hundred forty-one plant disease-resistance genes (R-genes) were detected by searching C. serrulata within the PRGdb. This research provides high-quality genomic information about C. serrulata as well as insights into the evolutionary history of Cerasus species.

15.
J Clin Transl Hepatol ; 8(3): 246-254, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-33083246

RESUMO

Background and Aims: Coronavirus disease 2019 (COVID-19) is a new respiratory infectious disease caused by severe acute respiratory syndrome coronavirus-2 (commonly known as SARS-CoV-2) with multiple organ injuries. The aim of this study was to analyze COVID-19-associated liver dysfunction (LD), its association with the risk of death and prognosis after discharge. Methods: Three-hundred and fifty-five COVID-19 patients were recruited. Clinical data were collected from electronic medical records. LD was evaluated and its prognosis was tracked. The association between LD and the risk of death was analyzed. Results: Of the 355 COVID-19 patients, 211 had mild disease, 88 had severe disease, and 51 had critically ill disease. On admission, 223 (62.8%) patients presented with hypoproteinemia, 151(42.5%) with cholestasis, and 101 (28.5%) with hepatocellular injury. As expected, LD was more common in critically ill patients. By multivariate logistic regression, male sex, older age and lymphopenia were three important independent risk factors predicting LD among COVID-19 patients. Risk of death analysis showed that the fatality rate was higher in patients with hypoproteinemia than in those without hypoproteinemia (relative risk=9.471, p<0.01). Moreover, the fatality rate was higher in patients with cholestasis than those without cholestasis (relative risk=2.182, p<0.05). Follow-up observation found that more than one hepatic functional index of two-third patients remained abnormal at 14 days after discharge. Conclusions: LD at early disease stage elevates the risk of death of COVID-19 patients. COVID-19-associated LD does not recover completely by 14 days after discharge.

16.
Echocardiography ; 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-33084159

RESUMO

OBJECTIVE: This study aimed to quantitatively evaluate the left ventricular myocardial work of patients with chronic kidney disease (CKD) by echocardiographic pressure-strain loop (PSL) analysis. METHODS: Ninety-three patients with CKD and forty-two age- and sex-matched controls were included in the study. CKD patients were divided into group 1 (stages 2-4) and group 2 (stage 5). Left ventricular blood pressure was estimated noninvasively according to echocardiographic valvular events and brachial artery systolic pressure. Left ventricular myocardial work parameters were acquired by echocardiographic PSL analysis. RESULTS: The CKD groups had a significantly lower global work index (WI), global work efficiency (GWE), global constructive strain (GCW) and global longitudinal strain (GLS) and higher global waste work (GWW) than the control group. Segmental analysis showed that the myocardial WI, work efficiency (WE), and constructive work (CW) were lower in group 2 than the control group (P < .05), while the regional myocardial waste work (WW) was higher (P < .05). A Pearson correlation analysis revealed that GWE and GWW have good correlations with the LVEF and GLS. A multiple regression analysis showed that the systolic blood pressure (SBP), estimated glomerular filtration rate (eGFR), end-diastolic volume (EDV), and GLS were associated with global work index (GWI) (b' = 0.476, 0.252, -0.407, and -0.355, P < .05). CONCLUSIONS: Left ventricular PSL analysis can be applied to assess global and regional myocardial work in CKD patients. This approach may serve as a noninvasive method for the detection of left ventricular systolic dysfunction at an early stage.

17.
Chemosphere ; 264(Pt 1): 128400, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-33007572

RESUMO

Gangue backfilling mining (GBM) can effectively alleviate the gangue accumulation pollution and the overburden aquifer destruction. To efficiently evaluate the reutilization of gangue wastes by GBM and its advantage in overburden aquifer protection, non-Darcy hydraulic properties and deformation behaviors of granular gangues were studied through laboratorial, theoretical, and in-situ aspects. A series of compression and seepage tests on granular gangues under the variable original grain size grade (GSG) and stress rate were conducted. Laboratorial testing results convince that, hydraulic properties (porosity and permeability) of the granular gangue decline with the increasing original GSG and decreasing stress rate. The crushing ratio of the sample increases with the increase of original GSG and the decrease of stress rate. The fractal dimension reveals more obvious increases in the samples with the higher original GSGs and lower stress rates. The Kruger model (a classical theoretical model) was employed to predict the permeability evolution based on the porosity. However, the invalid pores in rocks would result in the model's underestimation. To this end, an improved model was established to predict the permeability evolution by the fractal dimension, and the improved Kruger model has better accuracy than the original one. Finally, according to the laboratorial testing and theoretical predicted results, friendly-environmental strategies for overburden aquifer protection were proposed. The effectiveness of these strategies was successfully verified by an in-situ application. It is concluded that the high filling stress, low gangue original GSG, and low filling stress rate in GBM can effectively reduce the risk of overburden aquifer destruction.

18.
J Neurosci ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046545

RESUMO

Local measures of neurotransmitters provide crucial insights into neurobiological changes underlying altered functional connectivity in psychiatric disorders. However, non-invasive neuroimaging techniques such as magnetic resonance spectroscopy (MRS) may cover anatomically and functionally distinct areas, such as p32 and p24 of the pregenual anterior cingulate cortex (pgACC). Here, we aimed to overcome this low spatial specificity of MRS by predicting local glutamate and GABA based on functional characteristics and neuroanatomy in a sample of 88 human participants (35 females), using complementary machine learning approaches. Functional connectivity profiles of pgACC area p32 predicted pgACC glutamate better than chance (R2 = .324) and explained more variance compared to area p24 using both elastic net and partial least squares regression. In contrast, GABA could not be robustly predicted. To summarize, machine learning helps exploit the high resolution of fMRI to improve the interpretation of local neurometabolism. Our augmented multimodal imaging analysis can deliver novel insights into neurobiology by using complementary information.SIGNIFICANCE STATEMENTMagnetic resonance spectroscopy (MRS) measures local glutamate and GABA non-invasively. However, conventional MRS requires large voxels compared to fMRI, due to its inherently low signal-to-noise ratio. Consequently, a single MRS voxel may cover areas with distinct cytoarchitecture. In the largest multimodal 7 Tesla machine learning study to date, we overcome this limitation by capitalizing on the spatial resolution of fMRI to predict local neurotransmitters in the PFC. Critically, we found that prefrontal glutamate could be robustly and exclusively predicted from the functional connectivity fingerprint of one out of two anatomically and functionally defined areas that form the pregenual anterior cingulate cortex. Our approach provides greater spatial specificity on neurotransmitter levels, potentially improving understanding of altered functional connectivity in mental disorders.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33048269

RESUMO

Atrial size and function are closely correlated with atrial contributions to cardiovascular performance. Therefore, in this study, we aimed to assess atrial size and function in pediatric heart transplantation (HTx) patients using three-dimensional echocardiography (3DE). We enrolled 33 clinically well pediatric HTx patients and 33 healthy controls with a similar distribution of sex and age to the HTx patients. All patients underwent two-dimensional echocardiography (2DE) and 3DE. 2DE- and 3DE-derived biatrial maximal volume (Vmax), minimal volume (Vmin), ejection volume (EV), ejection fraction (EF), volume before atrial contraciton (VpreA), passive EV, passive EF, active EV and active EF were obtained in all patients. The 3D left atrail (LA) Vmax, Vmin and VpreA increased significantly in HTx patients after being indexed by BSA, while 3D LAEV and passive EV decreased significantly (P < 0.05). Moreover, the 3D LAEF, LA passive EF, and LA active EF all decreased significantly in HTx patients (P < 0.05). The 3D right atrial (RA) Vmax, Vmin, and VpreA increased significantly in HTx patients (P < 0.05), while the 3D RAEF and RA passive EF decreased significantly in HTx patients (P < 0.05). 3DE-derived LAVmax, LAVpreA, LA passive EV, LAEF, and LA passive EF were all lower than the corresponding 2D parameters. 3DE-derived RAVpreA, RA passive EV and RAEF were all lower than the corresponding 2D parameters. Atrial sizes and function assessed by 3DE- and 2DE-derived parameters, yield significantly discordant results in pediatric HTx patients. 3DE confirms significantly enlarged atrial sizes and decreased atrial functions in pediatric HTx patients.

20.
BMC Bioinformatics ; 21(1): 478, 2020 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-33099301

RESUMO

BACKGROUND: Introns have been shown to be spliced in a defined order, and this order influences both alternative splicing regulation and splicing fidelity, but previous studies have only considered neighbouring introns. The detailed intron splicing order remains unknown. RESULTS: In this work, a method was developed that can calculate the intron splicing orders of all introns in each transcript. A simulation study showed that this method can accurately calculate intron splicing orders. I further applied this method to real S. pombe, fruit fly, Arabidopsis thaliana, and human sequencing datasets and found that intron splicing orders change from gene to gene and that humans contain more not in-order spliced transcripts than S. pombe, fruit fly and Arabidopsis thaliana. In addition, I reconfirmed that the first introns in humans are spliced slower than those in S. pombe, fruit fly, and Arabidopsis thaliana genome-widely. Both the calculated most likely orders and the method developed here are available on the web. CONCLUSIONS: A novel computational method was developed to calculate the intron splicing orders and applied the method to real sequencing datasets. I obtained intron splicing orders for hundreds or thousands of genes in four organisms. I found humans contain more number of not in-order spliced transcripts.

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