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1.
Artigo em Inglês | MEDLINE | ID: mdl-33792796

RESUMO

PURPOSE: Platelets contain a rich repertoire of RNA species, such as mRNAs and long non-coding RNAs. During the development of tumors, platelets are "educated" by cancer cells, altering their transcriptome and molecular content, thereby, tumor educated platelet (TEP) lncRNA profile has the potential to diagnose lung cancer. The current study was aimed to examine whether TEPs might be a potential biomarker for lung cancer. METHODS: Platelet precipitation was obtained by low-speed centrifugation. TEP linc-GTF2H2-1, RP3-466P17.2, and lnc-ST8SIA4-12 were selected by lncRNA microarray and validated by qPCR in a large cohort of lung cancer patients and healthy donors. Besides, we analyzed the association of their expression levels with clinicopathological features. RESULTS: TEP linc-GTF2H2-1 and RP3-466P17.2 were significantly downregulated, while lnc-ST8SIA4-12 was significantly upregulated in patients with lung cancer or with early-stage lung cancer as compared to healthy donors, possessing AUCs of 0.781, 0.788, 0.725 for lung cancer and 0.704, 0.771, 0.768 for early-stage lung cancer, respectively. Notably, their combination demonstrated the markedly elevated AUCs of 0.921 for lung cancer and 0.895 for early-stage lung cancer. Besides, the combination of TEP linc-GTF2H2-1 was capable to facilitate diagnostic efficiencies of CEA, Cyfra21-1, or NSE to distinguish advanced-stage lung cancer patients from early ones, with an AUC of 0.899 based on the integration of these four factors. CONCLUSION: Our data suggested that lncRNAs sequestered in TEPs enabled blood-based lung cancer diagnosis and progression prediction.

2.
Langmuir ; 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33793250

RESUMO

A large subset of haptic surfaces employs electroadhesion to modulate both adhesion and friction at a sliding finger interface. The current theory of electroadhesion assumes that the applied electric field pulls the skin into stronger contact, increasing friction by increasing the real contact area, yet it is unknown what role environmental moisture plays in the effect. This paper uses atomic force microscopy (AFM)to determine the effect of humidity on the adhesion and friction between the single nanoscale asperity and individual human finger corneocytes. An analytical model of the total effective load of the AFM tip is developed to explain the humidity-voltage dependence of nanoscale adhesion and friction at contacting asperities. The results show that the electrowetting effect at the interface at high humidity accounts for 35% of the adhesive force but less than 8% of the total friction, implying that the electrowetting effect can be enhanced by optimizing surface topography to promote the formation and rupture of liquid menisci.

3.
Heart Surg Forum ; 24(2): E327-E332, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33798049

RESUMO

BACKGROUND: In recent years, galectin-3, an inflammatory marker, has been demonstrated to be closely related to cardiac fibrosis and heart failure. The purpose of this systematic review and meta-analysis is to define galectin-3 in predicting mortality of heart failure. METHODS: PubMed, Embase, and the Cochrane Library were searched. A total of 1540 studies were identified, and of these studies, 19 involving 9217 patients were included in our meta-analysis. RESULTS: The diagnostic hazard ratios of galectin-3 in predicting mortality in chronic heart failure patients was 1.13 (95% CI,:1.07-1.21 ) and 2.17 (95% CI:1.27-3.08) in acute heart failure (HF) patients. CONCLUSIONS: Our meta-analysis shows that elevated levels of galectin-3 are associated with higher mortality in both acute and chronic heart failure patients.

4.
PLoS One ; 16(4): e0248182, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33798203

RESUMO

Impatiens L., the largest genus in the family Balsaminaceae with approximately 1000 species, is a controversial and complex genus that includes many economically important species well known for medicinal and ornamental values. However, there is limited knowledge of molecular phylogeny and chloroplast genomics, and uncertainties still exist at a taxonomic level. In this study, we have assembled four chloroplast genomics specimens of Impatiens cyanantha and Impatiens monticola, which are found at the different altitudes of Guizhou and Yunnan in China, and compared them with previously published three wild Balsaminaceae species (Impatiens piufanensis, Impatiens glandlifera, and Hydrocera triflora). The complete chloroplast genome sequences ranged from 152,236 bp (I. piufanensis) to 154,189 bp (H. triflora) and encoded 115 total distinct genes, of which 81 were protein-coding, 30 were distinct transfer RNA genes(tRNA), and 4 were ribosomal RNA genes (rRNA). A comparative analysis of I. cyanantha (Guizhou) vs. I. cyanantha (Yunnan) and I. monticola (Guizhou) vs. I. monticola (Yunnan) revealed minor changes in lengths; however, similar gene contents, gene orders, and GC contents existed among them. Interestingly, highly coding and non-coding genes, and regions matK, psbK, atpH-atpI, trnC-trnT, petN, psbM, atpE, rbcL, accD, psaL, rps3-rps19, ndhG-ndhA,rpl16, rpoB, ndhB, ndhF, ycf1, and ndhH were found, which could be suitable for identification of species and phylogenetic studies. During the comparison between I. cyanantha (Guizhou) and I. cyanantha (Yunnan), we observed that the rps4, ycf2, ndhF, ycf1, and rpoC2 genes underwent positive selection. Meanwhile, in the comparative study of I. monticola (Guizhou) vs. I. monticola (Yunnan), The accD and ycf1 genes were positively selected. Additionally, phylogenetic relationships based on maximum likelihood (ML) and Bayesian inference (BI) among whole chloroplast genomes showed that a sister relationship with I. monticola (Guizhou) and I. monticola (Yunnan) formed a clade with I.piufanensis proving their close connection. Besides, I.cyanantha (Guizhou) and I. cyanantha (Yunnan) formed a clade with I. glandlifera. Along with the findings and the results, the current study might provide valuable significant genomic resources for systematics and evolution of the genus impatiens in different altitudes of regions.

5.
J Colloid Interface Sci ; 594: 254-264, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33765645

RESUMO

Developing low-cost non-precious metals as efficient catalysts for the reduction of toxic 4-nitrophenol (4-NP) to useful 4-aminophenol (4-AP) have received increasing attention in recent years. Herein, a novel and efficient Cu-based catalyst Cu/CuxO@CN (carbon doped with nitrogen) was prepared via a facile method from pyrolysis of bi-ligand MOFs material Cu2(BDC)2(BPY) (BDC = p-Phthalic acid, BPY = 4,4'-bipyridyl) in Ar atmosphere. Characterization results revealed that N doping in carbon matrix favors the development of mesoporous structure, the formation of more defect sites in carbon matrix, better dispersion of Cu/CuxO nano particles, and maintenance of Cu species in metallic Cu state (the active site), all of which contribute to a superior catalytic activity for 4-NP reduction with a pseudo-first-order rate constant as high as 0.126 s-1 (the molar ratio of NaBH4 to 4-NP is 400), nearly 11 times higher than its counterpart Cu/CuxO@C without N doping (0.011 s-1). The activation energy for 4-NP reduction to 4-AP catalyzed by Cu/CuxO@CN was determined as 55.6 kJ mol-1 (the molar ratio of NaBH4 to 4-NP is 100). In addition, Cu/CuxO@CN showed excellent reusability in successive 6 cycles. The facile synthesis and superior catalytic activity make Cu/CuxO@CN a promising catalyst in industrial applications for many other similar reaction systems.

6.
Sleep Breath ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33770380

RESUMO

PURPOSE: Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) have a higher risk of obstructive sleep apnea (OSA). However, the relationship between CRSwNP and OSA remains unclear. The aim of this research study was to evaluate the association of multiple single nucleotide polymorphism (SNP) variations in CRSwNP with sleep- and breath-related parameters in men with OSA. METHODS: We included eight CRSwNP SNPs in 2320 participants after strict screening. For each participant, the genetic risk score (GRS) was calculated based on the cumulative effect of multiple genetic variants of CRSwNP. A bivariate correlation analysis was used to assess the relationship between CRSwNP genetic polymorphisms and polysomnography parameters in men with OSA. Logistic regression analyses were used to assess the relationship between the risk of OSA and CRSwNP genetic polymorphisms. RESULTS: In moderate OSA, rs28383314 was related to the oxygen desaturation index, and rs4807532 was positively associated with the microarousal index (r = 0.09, P = 0.03 and r = 0.11, P = 0.01, respectively). The CRSwNP GRS was positively correlated with the oxygen desaturation index and cumulative time percentage with SpO2 < 90% in moderate OSA (r = 0.13, P < 0.001 and r = 0.1, P = 0.01, respectively). There was no association between the CRSwNP GRS and the risk of OSA (OR = 1.007; 95% CI, 0.973-1.042; P = 0.702). CONCLUSION: In men with moderate OSA, single CRSwNP genetic variations correlated with sleep-related parameters, and the cumulative effects of CRSwNP genetic variations were associated with the hypoxic index. CRSwNP may be a predisposing condition for sleep disorders in men with moderate OSA.

8.
Int Wound J ; 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33675188

RESUMO

The purpose of this study was to identify the risk factors for complications of perforator flaps in plantar reconstruction. A systematic review was performed by searching the PubMed, Cochrane Library, MEDLINE, and EMBASE databases from their inception date up to October 2020. Only studies on reconstructing plantar defects with perforator flaps were included, and specific data were required for each patient in the included studies. A total of 14 studies involving 111 flaps were identified and included in the meta-analysis. Our meta-analysis identified two risk factors for postoperative complications: flap size over 50 cm2 (risk ratio [RR] = 3.12; P = .02), diabetes mellitus foot (RR = 3.26; P = .03). No significant differences were found regarding heel defects (P = .34), single perforator (P = .57), age older than 60 years (P = .19), chronic aetiology (P = .13), trauma (P = .33), tumour resection (P = .60), ulcer (P = .84), and burn (P = .76). Although more high-quality studies with adequate sample sizes are needed, this meta-analysis indicated that flap size over 50 cm2 and diabetes mellitus foot were significant risk factors for postoperative complications of perforator flaps in plantar reconstruction.

9.
Talanta ; 226: 122089, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33676647

RESUMO

The reliable determination of the Ag(I) affinity for biomolecules is an essential issue in the fields of structural analysis and sensor design. However, the urgent problem confronting researchers is lack of a direct and accurate Ag(I) affinity evaluation as a reference standard for ligand analysis. We communicated here a straightforward and high-efficiency method of measuring Ag(I) affinity exactly on the basis of the unique calculation algorithm and the design of a special peptide RFPRDD (P) as Ag(I) binding motif. According to UV-vis competition between the corresponding complexes (AgP) and biomolecules (peptides, amino acids and ssDNA), the decrease of the signature at 300 nm characteristic of AgP was obtained for quantitative analysis. The primary advantages of this strategy were the widespread application, high accuracy and reference significance, which were corroborated by theoretical calculations. To identify its potential in biosensing, two kinds of testing models for Ag(I) were proposed by AgBP2-decorated and Ag4-decorated gold nanoparticles, the detection limits of which were 2 nM and 75 nM respectively. By contrast of the sensing property of the functional peptides (AgBP2, Ag4), we afforded evidence that this conception could be regarded as an evaluation criterion for the selection and performance optimization of sensitive elements, thereby holding a dominant position in the biosensors.

10.
Reproduction ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33780908

RESUMO

Decidualization is the functional transformation process of endometrium in re-sponse to ovarian steroids dedicated to support the embryo development. Defective decidualization is closely associated with various pregnancy complications such as recurrent miscarriage (RM). Dual specificity MAPK phosphatases (MKPs) are a family of phosphatases specifically regulating MAPK signaling with dual specificity for threonine and tyrosine. Here, using RNA-seq we found Dual specificity phospha-tase 1 (DUSP1) expression was prominently elevated among the MKP family mem-bers in db-cAMP treated primary human endometrial stromal cells (ESCs). We veri-fied that its induction by db-cAMP in ESCs was in a dose- and time-dependent man-ner and that primary human decidual stromal cells (DSCs) present higher expression of DUSP1 than ESCs. A PKA inhibitor H-89 abolished its induction in ESCs, but not ESI-09, an EPAC1/2 inhibitor. Knock-down of TORC2/3 but not CREB by siRNA in ESCs diminished its induction by db-cAMP. Furthermore, knock-down of DUSP1, as well as TORC2/3 by siRNA caused abnormal activation of JNK during db-cAMP in-duction in ESCs, accompanied by decreased IGFBP1 expression, an ESC deciduali-zation indicator, which could be fully rescued by a JNK inhibitor SP600125. In addi-tion, Western blot showed that DUSP1 expression was reduced in the DSCs of pa-tients with RM, along with JNK overactivation and decreased IGFBP1 expression. In conclusion, our results demonstrated that TORC2/3-mediated DUSP1 upregulation in response to the cAMP/PKA signaling safeguards IGFBP1 expression via restrain-ing JNK activity, indicating its involvement in ESC decidualization, and that aber-rant expression of DUSP1 in DSCs might engage in the pathogenesis of RM.

12.
Colloids Surf B Biointerfaces ; 200: 111594, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33561693

RESUMO

The low therapeutic effect and strong side-effect are the major barriers for clinical chemotherapy. Herein, a pH-responsive nanoplatform based-silk sericin-zeolitic imidazolate framework-8 was designed for the delivery of chemotherapeutic doxorubicin (denoted as ZIF-8@DOX@SS, ZDS), which can overcome the limitation of poor circulation stability and unexpected drug leakage in blood circulation, producing a satisfactory chemotherapy. Concretely, ZIF-8 structure shows better stability and biocompatibility owing to the protection of a nature and non-toxic sericin protein. When it comes to low pH environment (e.g. in tumor cell microenvironment), the coordination effect in ZIF-8 will be broken and release DOX drugs. The nano-sized morphology endow ZDS an efficient drug uptake and significant tumor permeability efficiency. Furthermore, the tumor-specific biodegradability makes ZDS possible to realize targeted and enhanced chemotherapy. Considering all the advantages in the study, this silk sericin-based nanosystem represent a promising strategy for the design of stimuli-responsive by using natural polymer to improve the treatment effect of chemotherapy.

13.
Am J Orthod Dentofacial Orthop ; 159(4): 426-434.e5, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33568273

RESUMO

INTRODUCTION: This study aimed to build an experimental immature tooth movement model and verify less resorption of incompletely developed roots than those fully developed during the same orthodontic treatment, followed by investigating the cellular and molecular mechanism. METHODS: The development of Wistar rat tooth was investigated using in vivo microcomputed tomography and hematoxylin and eosin staining to decide the optimal ages of rats for immature tooth and mature tooth groups. The rats in the immature tooth and mature tooth groups were divided into experimental, sham control, and blank control groups. After orthodontic treatment for 3 weeks, the mesial root volume, crown movement distance, neck movement distance, root inclination, and apical distance were measured by microcomputed tomography. The expressions of TRAP, Jagged1, Notch2, IL-6, and RANKL were analyzed by immunohistochemical staining and real-time polymerase chain reaction. The repair of root resorption was also investigated after removing orthodontic force for 3 and 6 weeks. RESULTS: The root achieved the development stage around 10 weeks, so 4-week-old rats and 10-week-old rats were used in the immature tooth group and mature tooth group, respectively. The volume of root resorption in the experimental immature tooth group was 0.0869 ± 0.0244 mm3, which was less than that in the mature tooth group (0.1218 ± 0.0123 mm3) (P <0.001). Immature tooth movement decreased TRAP-positive odontoclasts on the compression side while having no statistically significant effect on osteoclasts. The protein expression of Jagged1, Notch2, IL-6, and RANKL in the mature tooth group increased significantly compared with the immature tooth group, not only on the compression side but also on the tension sides. The mRNA expression of Jagged1, Notch2, and RANKL was significantly lower in the immature tooth group, whereas the expression of IL-6 had no significance but a strong tendency. The root volume after repairing for 3 weeks was still less than that of blank control, whereas after repairing for 6 weeks, the difference was not statistically significant. CONCLUSIONS: The experimental immature tooth movement model for the Wistar rat was achieved for the first time. The immature tooth will suffer less root resorption than the mature tooth, which may be due to odontoclastogenesis inhibition by decreased expression of Jagged1/Notch2/IL-6/RANKL signaling.


Assuntos
Reabsorção da Raiz , Animais , Osteoclastos , Ratos , Ratos Wistar , Reabsorção da Raiz/etiologia , Reabsorção da Raiz/prevenção & controle , Técnicas de Movimentação Dentária , Raiz Dentária , Microtomografia por Raio-X
14.
Obes Surg ; 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33569729

RESUMO

PURPOSE: Body fat indices serve as predictive markers of insulin resistance (IR) in metabolic diseases. IR is common in obstructive sleep apnea (OSA). However, whether body fat indices have utility as predictors of IR in OSA remain unknown. MATERIALS AND METHODS: A longitudinal study was conducted in 46 patients undergoing bariatric surgery to explore the relationship between IR and body fat indices. Then, a cross-sectional study was performed to evaluate the relationships between body fat indices and IR, and receiver operating characteristic (ROC) curves were generated. Body indices, homeostasis model assessment index of insulin resistance (HOMA-IR), biological indicators, and polysomnographic variables were collected. RESULTS: In the longitudinal study, significant relationships were found between remission of IR and changes in visceral adiposity index (VAI) (r = 0.452, P < 0.05) and triglyceride-glucose index (TyG) (r = 0.650, P < 0.01). In the cross-sectional study, lipid accumulation product (LAP) (best cutoff value: 30.16, area under the curve (AUC) = 0.728, P < 0.001) and TyG (best cutoff value: 8.54, AUC = 0.740, P < 0.001) were indicators of IR in normal weight group. In overweight/obese group, body mass index (BMI) (best cutoff value: 27.69 AUC = 0.707, P < 0.001) and waist circumference (WC) (best cutoff value: 97.25, AUC = 0.708, P < 0.001) were markers of IR. TyG showed better ability to predict IR in normal weight females (best cutoff value: 8.39 AUC = 0.813, P < 0.001). CONCLUSIONS: Body fat indices are predictive markers of IR in patients with OSA.

15.
Med Phys ; 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33577108

RESUMO

PURPOSE: To develop an Artificial-Intelligence (AI) agent for fully automated rapid head-and-neck IMRT plan generation without time-consuming dose-volume-based inverse planning. METHODS: This AI agent was trained via implementing a conditional Generative Adversarial Network (cGAN) architecture. The generator, PyraNet, is a novel Deep Learning network that implements 28 classic ResNet blocks in pyramid-like concatenations. The discriminator is a customized 4-layer DenseNet. The AI agent first generates multiple customized 2D projections at 9 template beam angles from a patient's 3D CT volume and structures. These projections are then stacked as 4D inputs of PyraNet, from which 9 radiation fluence maps of the corresponding template beam angles are generated simultaneously. Finally, the predicted fluence maps are automatically post-processed by Gaussian deconvolution operations and imported into a commercial treatment planning system (TPS) for plan integrity check and visualization. The AI agent was built and tested upon 231 oropharyngeal IMRT plans from a TPS plan library. 200/16/15 plans were assigned for training/validation/testing, respectively. Only the primary plans in the sequential boost regime were studied. All plans were normalized to 44Gy prescription (2Gy/fx). A customized Harr wavelet loss was adopted for fluence map comparison during the training of the PyraNet. For test cases, isodose distributions in AI plans and TPS plans were qualitatively evaluated for overall dose distributions. Key dosimetric metrics were compared by Wilcoxson Signed Rank tests with a significance level of 0.05. RESULTS: All 15 AI plans were successfully generated. Isodose gradients outside of PTV in AI plans were comparable to those of the TPS plans. After PTV coverage normalization, Dmean of left parotid (DAI =23.1±2.4Gy; DTPS =23.1±2.0Gy), right parotid (DAI =23.8±3.0Gy; DTPS =23.9±2.3Gy), and oral cavity (DAI =24.7±6.0Gy; DTPS =23.9±4.3Gy) in the AI plans and the TPS plans were comparable without statistical significance. AI plans achieved comparable results for maximum dose at 0.01cc of brainstem (DAI =15.0±2.1Gy; DTPS =15.5±2.7Gy) and cord+5mm (DAI =27.5±2.3Gy; DTPS =25.8±1.9Gy) without clinically-relevant differences, but body Dmax results (DAI =121.1±3.9Gy; DTPS =109.0±0.9Gy) were higher than the TPS plan results. The AI agent needed ~3s for predicting fluence maps of an IMRT plan. CONCLUSIONS: With rapid and fully automated execution, the developed AI agent can generate complex head-and-neck IMRT plans with acceptable dosimetry quality. This approach holds great potential for clinical applications in pre-planning decision-making and real-time planning.

16.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(2): 186-191, 2021 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-33627216

RESUMO

OBJECTIVE: To study the clinical application of the modified nutritional risk screening tool and nutrition assessment in pediatric patients in China, and to provide a theoretical basis for establishing a standardized nutritional management process for pediatric patients. METHODS: A retrospective analysis was performed for the nutritional risk screening and nutrition assessment data of 16 249 hospitalized children. According to the degree of nutritional risk, the children were divided into a high nutritional risk group with 588 children, a moderate nutritional risk group with 4 330 children, and a non-nutritional risk group with 11 331 children. Nutrition assessment results were compared between groups. The composition of nutritional risk screening scores and the impact of nutritional risk screening on the rate of nutrition support therapy were analyzed. RESULTS: The incidence rate of nutritional risk was 30.27% (4 918/16 249), and the incidence rates of malnutrition and overnutrition were 27.37% (4 448/16 249) and 11.29% (1 834/16 249), respectively. Nutrition assessment results were significantly correlated with nutritional risk (≥ 5 years old:rs=0.313, P < 0.05; < 5 years old:rs=-0.304, P < 0.05). There was a significant difference in the composition of scoring items between the groups with different nutritional risks (P < 0.05). With the implementation of nutritional risk screening, there was a gradual increase in the rate of nutrition support therapy year by year (P < 0.05). CONCLUSIONS: There is a high incidence rate of nutritional risk in hospitalized children. The use of the modified pediatric nutritional risk screening tool can promote the implementation of standardized nutritional management.


Assuntos
Desnutrição , Avaliação Nutricional , Criança , Pré-Escolar , China/epidemiologia , Humanos , Estado Nutricional , Estudos Retrospectivos
17.
Artigo em Inglês | MEDLINE | ID: mdl-33579028

RESUMO

Paddy fields are significant in ensuring food security and improving the agricultural ecological environment. In economic terms, paddy field use is affected by input costs and crop market price. There is insufficient understanding of factor input costs caused by agricultural production-factor substitution, driving paddy field change. This study uses a panel regression model to analyze the influence of agricultural production-factor substitution on paddy field use from 1990 to 2016. The case area is Hubei province, China. The results show that the overall growth trend in paddy fields is unequivocal in China's grain production areas. The improvement in agricultural production conditions, including irrigation and land quality, has a positive effect on the area proportion of paddy fields. With socioeconomic developments, the relationship between the substitution of nitrogen fertilizer for farmland and the area proportion of paddy field is inverted-U shaped, while the effect of the substitution of machinery for labor is U-shaped. The main conclusion is that the process of agricultural production-factor substitution, intended to maximize labor and land productivity, will increase the area proportion of paddy field. Public policies should focus on improving the level of agricultural mechanization and crop diversity to protect food security and sustainable agricultural intensification.

18.
Chemosphere ; 271: 129511, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33445016

RESUMO

The gastrointestinal tract is the largest immune organ in the body and meanwhile, accommodates a large number of microorganisms. Heavy metals could disturb the intestinal homeostasis and change the gut microbial composition. However, the information regarding the links between dysbiosis of gut microbiota and imbalance of host intestinal homeostasis induced by the mixture of heavy metals is insufficient. The present study investigates the effects of Cd/Pb, both single and combination exposure, on the growth performance, intestinal histology, digestive enzymes activity, oxidative stress and immune parameters, and intestinal microbiota in Bufo gargarizans tadpoles. Our results revealed that co-exposure of Cd-Pb induced more severe impacts not only on the host, but the intestinal microbiota. On the one hand, co-exposure of Cd-Pb significantly induced growth retardation, intestinal histological injury, decreased activities of digestive enzymes. On the other hand, Cd and Pb exposure, especially in mixed form, changed the diversity and richness, structure of microbiota. Also, the intestinal microbial composition was altered by Cd/Pb exposure (alone and combination) both at the different levels. Proteobacteria, act as front-line responder, was significantly increased in tadpoles under the exposure of metals. Finally, the functional prediction revealed that the disorders of metabolism and immune responses of intestinal microbiota was increased in tadpoles exposed to Cd/Pb (especially the mixture of Cd and Pb). Our research complements the understanding of links between changes in host fitness loss and intestinal microbiota and will add a new dimension of knowledge to the ecological risks of mixed heavy metals in amphibian.


Assuntos
Cádmio , Disbiose , Animais , Bufonidae , Cádmio/toxicidade , Disbiose/induzido quimicamente , Trato Gastrointestinal , Chumbo/toxicidade
19.
Sci Total Environ ; 768: 144516, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33453525

RESUMO

The main component of haze is the particulate matter (PM) 2.5. How to explore the laws of PM2.5 concentration changes is the main content of air quality prediction. Combining the characteristics of temporality and non-linearity in PM2.5 concentration series, more and more deep learning methods are currently applied to PM2.5 predictions, but most of them ignore the non-stationarity of time series, which leads to a lower accuracy of model prediction. To address this issue, an integration method of gated recurrent unit neural network based on empirical mode decomposition (EMD-GRU) for predicting PM2.5 concentration was proposed in this paper. This method uses empirical mode decomposition (EMD) to decompose the PM2.5 concentration sequence first and then fed the multiple stationary sub-sequences obtained after the decomposition and the meteorological features into the constructed GRU neural network successively for training and predicting. Finally, the sub-sequences of the prediction output are added to obtain the prediction results of PM2.5 concentration. The forecast result of the case in this paper show that the EMD-GRU model reduces the RMSE by 44%, MAE by 40.82%, and SMAPE by 11.63% compared to the single GRU model.

20.
Nat Commun ; 12(1): 408, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462233

RESUMO

Reservoir computing is a highly efficient network for processing temporal signals due to its low training cost compared to standard recurrent neural networks, and generating rich reservoir states is critical in the hardware implementation. In this work, we report a parallel dynamic memristor-based reservoir computing system by applying a controllable mask process, in which the critical parameters, including state richness, feedback strength and input scaling, can be tuned by changing the mask length and the range of input signal. Our system achieves a low word error rate of 0.4% in the spoken-digit recognition and low normalized root mean square error of 0.046 in the time-series prediction of the Hénon map, which outperforms most existing hardware-based reservoir computing systems and also software-based one in the Hénon map prediction task. Our work could pave the road towards high-efficiency memristor-based reservoir computing systems to handle more complex temporal tasks in the future.

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