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1.
Invest Ophthalmol Vis Sci ; 65(5): 7, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38700875

RESUMO

Purpose: This study aimed to explore the underlying mechanisms of the observed visuomotor deficit in amblyopia. Methods: Twenty-four amblyopic (25.8 ± 3.8 years; 15 males) and 22 normal participants (25.8 ± 2.1 years; 8 males) took part in the study. The participants were instructed to continuously track a randomly moving Gaussian target on a computer screen using a mouse. In experiment 1, the participants performed the tracking task at six different target sizes. In experiments 2 and 3, they were asked to track a target with the contrast adjusted to individual's threshold. The tracking performance was represented by the kernel function calculated as the cross-correlation between the target and mouse displacements. The peak, latency, and width of the kernel were extracted and compared between the two groups. Results: In experiment 1, target size had a significant effect on the kernel peak (F(1.649, 46.170) = 200.958, P = 4.420 × 10-22). At the smallest target size, the peak in the amblyopic group was significantly lower than that in the normal group (0.089 ± 0.023 vs. 0.107 ± 0.020, t(28) = -2.390, P = 0.024) and correlated with the contrast sensitivity function (r = 0.739, P = 0.002) in the amblyopic eyes. In experiments 2 and 3, with equally visible stimuli, there were still differences in the kernel between the two groups (all Ps < 0.05). Conclusions: When stimulus visibility was compensated, amblyopic participants still showed significantly poorer tracking performance.


Assuntos
Ambliopia , Acuidade Visual , Humanos , Ambliopia/fisiopatologia , Masculino , Feminino , Adulto , Adulto Jovem , Acuidade Visual/fisiologia , Psicofísica/métodos , Percepção de Movimento/fisiologia , Sensibilidades de Contraste/fisiologia , Movimentos Oculares/fisiologia
2.
Environ Res ; 238(Pt 1): 117142, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37739155

RESUMO

In wastewater treatment plants (WWTPs), aeration is vital for microbial oxygen needs. To achieve carbon neutrality, optimizing aeration for energy and emissions reduction is imperative. Machine learning (ML) is used in wastewater treatment to reveal complex rules in large data sets has become a trend. In this vein, the present paper proposes an aeration optimization approach based on the extreme gradient boosting-bidirectional long short-term memory (XGB-Bi-LSTM) model via the online monitoring of oxygen transfer efficiency (OTE) and oxygen uptake rate (OUR), thus allowing WWTPs to conserve energy and reduce indirect carbon emissions. The approach uses gain algorithm of XGB to calculate the importance of features and identify important parameters, and then uses Bi-LSTM to predict the target with important parameters as features. Operational data from a WWTP in Suzhou, China, is employed to train and test the approach, the performance of which is compared with ML models suitable for regression prediction tasks (XGB, random forest, light gradient boosting machine, gradient boosting and LSTM). Experimental results show the approach requires only a small number of input parameters to achieve good performance and outperforms other machine-learning models. When OTE and dissolved oxygen (DO) are used as features to predict the alpha factor (αF; since diffusers were used, multiply by the pollution factor F), the R-squared (R2) is 0.9977, the root mean square error (RMSE) is 0.0043, the mean absolute percentage error (MAPE) is 0.0069 and the median absolute error (MedAE) is 0.0032. When the predicted αF and the OUR are used as features to predict the air flow rate of an aeration unit, the R2 is 0.9901, the RMSE is 3.6150, the MAPE is 0.0209 and the MedAE is 1.5472. Using our optimized aeration approach, the energy consumption can be reduced by 23%.


Assuntos
Oxigênio , Purificação da Água , Oxigênio/análise , Águas Residuárias , Purificação da Água/métodos , Algoritmos , Carbono
3.
Environ Sci Pollut Res Int ; 30(32): 79258-79268, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37284948

RESUMO

With the increasingly serious eutrophication of global water bodies and the strict discharge standards of tail water in wastewater treatment plants (WWTPs), there is an urgent technology need for efficient deep phosphorus removal from wastewater. A composite cerium-based adsorbent (Ce-Zr-Al) was synthesized by coprecipitation method for the adsorption of low concentration phosphorus in water. The performance of the Ce-Zr-Al composite adsorbent was explored, and the mechanism was also revealed through the analyses including SEM, BET, XPS, and FT-IR. The results showed that the composite adsorbent had excellent phosphorus removal performance. The phosphorus removal rate reached up to 92.6%, and the phosphorus concentration in effluent was less than 0.074 mg/L. The phosphate adsorption capacity of saturation was 73.51 mg/g. The adsorption process of phosphate was in accordance with pseudo-second-order kinetic model and Langmuir model. In addition, the composite adsorbent had a high zero potential point (pH PZC= 8) and a wide range of pH application. After the repeated desorption for 10 times in NaOH solution, the composite adsorbent still maintained good adsorbability (adsorption rate > 94%). The ligand exchange and electrostatic adsorption played the main role for the phosphorus removal from water using the composite adsorbent.


Assuntos
Fósforo , Poluentes Químicos da Água , Águas Residuárias , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise , Fosfatos/análise , Cinética , Água/análise , Concentração de Íons de Hidrogênio
4.
Invest Ophthalmol Vis Sci ; 64(7): 25, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37318443

RESUMO

Purpose: Amblyopes are known to have delayed response times (RT) in various visual tasks. We aim to investigate whether any factor other than the sensory deficit contributes to the delayed RT in amblyopia. Method: Fifteen amblyopic (26.0 ± 4.50 years) and 15 normal (25.6 ± 2.90 years) participants took part in this study. The responses and RTs in an orientation identification task were collected for each participant with stimulus contrast adjusted to the multiples of individual's threshold. A drift diffusion model was used to fit to the response and RT data and to estimate the RT components. Result: There was a significant difference in the RT between the amblyopic and normal groups (F(1, 28) = 6.75, P = 0.015) but no difference in the accuracy (F(1, 28) = 0.028, P = 0.868). The drift rate function in the amblyopic eye had a larger threshold (P = 0.001) and shallower slope (P = 0.006) than that of the fellow eye. The amblyopic group has a longer non-decision time than the normal group (F(1, 28) = 8.02, P = 0.008). The drift rate threshold correlated with the contrast sensitivity (P = 1.71 × 10-18) but the non-decision time did not (P = 0.393). Conclusions: Both sensory and post-sensory factors contributed to the delayed RT in amblyopia. The effect of the sensory loss in V1 on RT can be compensated by increasing stimulus contrast, and the post-sensory delay provides evidence for higher-level deficits in amblyopia.


Assuntos
Ambliopia , Humanos , Tempo de Reação , Sensibilidades de Contraste
5.
Environ Sci Pollut Res Int ; 30(8): 21132-21143, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36264470

RESUMO

Activated sludge process was a low-cost alternative method compared to the conventional physicochemical process for the treatment of heavy metal-containing wastewater. In the present study, the removal efficiency of Pb2+, Cu2+, and Ni2+ from wastewater by a sequencing batch reactor (SBR) activated sludge system was investigated, and the mechanism was revealed by static adsorption experiment of activated sludge. The results showed that the activated sludge in the SBR system was effective in removing Pb2+ and Cu2+ from wastewater at 10 mg·L-1 initial concentration, with a removal efficiency of 83.1 ~ 90.0% for Pb2+ and 74.3 ~ 80.6% for Cu2+, respectively. However, the removal efficiency for Ni2+ was only 0 ~ 6.2%. Static adsorption experiments showed that the adsorption capacity of activated sludge for three heavy metals was shown as Pb2+ > Cu2+ > Ni2+. When the initial concentration was 20 mg·L-1, the equilibrium adsorption capacity of activated sludge for Pb2+, Cu2+, and Ni2+ was 18.35 mg·g-1, 17.06 mg·g-1, and 8.37 mg·g-1, respectively. The main adsorption mechanisms for Pb2+ and Cu2+ were ligand exchange, electrostatic adsorption, and surface organic complexation processes, but Ni2+ removal mechanism mainly included electrostatic adsorption and surface organic complexation processes, showing that Ni2+ removal was inhibited in the presence of Pb2+ and Cu2+. The physicochemical properties and microbial diversity of activated sludge were greatly affected by the heavy metals in the SBR system, and genus Rhodobacter was found to be dominant bacteria enabling resistance to heavy metal ions.


Assuntos
Metais Pesados , Águas Residuárias , Esgotos/química , Chumbo , Metais Pesados/análise , Adsorção
6.
Environ Int ; 170: 107598, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36395558

RESUMO

Characterizing the molecular mechanism through which different carbon sources affect the denitrification process would provide a basis for the proper selection of carbon sources, thus avoiding excessive carbon source dosing and secondary pollution while also improving denitrification efficiency. Here, we selected Thauera linaloolentis as a model organism of denitrification, whose genomic information was elucidated by draft genome sequencing and KEGG annotations, to investigate the growth kinetics, denitrification performances and characteristics of metabolic pathways under diverse carbon source conditions. We reconstructed a metabolic network of Thauera linaloolentis based on genomic analysis to help develop a systematic method of researching electron pathways. Our findings indicated that carbon sources with simple metabolic pathways (e.g., ethanol and sodium acetate) promoted the reproduction of Thauera linaloolentis, and its maximum growth density reached OD600 = 0.36 and maximum specific growth rate reached 0.145 h-1. These carbon sources also accelerated the denitrification process without the accumulation of intermediates. Nitrate could be reduced completely under any carbon source condition; but in the "glucose group", the maximum accumulation of nitrite was 117.00 mg/L (1.51 times more than that in the "ethanol group", which was 77.41 mg/L), the maximum accumulation of nitric oxide was 363.02 µg/L (7.35 times more than that in the "ethanol group", which was 49.40 µg/L), and the maximum accumulation of nitrous oxide was 22.58 mg/L (26.56 times more than that in the "ethanol group", which was 0.85 mg/L). Molecular biological analyses demonstrated that diverse types of carbon sources directly induced different carbon metabolic activities, resulting in variations in electron generation efficiency. Furthermore, the activities of the electron transport system were positively correlated with different carbon metabolic activities. Finally, these differences were reflected in the phenomenon of electronic competition between denitrifying reductases. Thus we concluded that this was the main molecular mechanism through which the carbon source type affected the denitrification process. In brief, carbon sources with simple metabolic pathways induced higher efficiency of electron generation, transfer, and competition, which promoted rapid proliferation and complete denitrification; otherwise Thauera linaloolentis would grow slowly and intermediate products would accumulate seriously. Our study established a method to evaluate and optimize carbon source utilization efficiency based on confirmed molecular mechanisms.


Assuntos
Carbono , Elétrons , Eletrônica
7.
Invest Ophthalmol Vis Sci ; 63(5): 3, 2022 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-35503229

RESUMO

Purpose: Neural selectivity of orientation is a fundamental property of visual system. We aim to investigate whether and how the orientation selectivity changes in amblyopia. Methods: Seventeen patients with amblyopia (27.1 ± 7.1 years) and 18 healthy participants (25.1 ± 2.7 years) took part in this study. They were asked to continuously detect vertical gratings embedded in a stream of randomly oriented gratings. Using a technique of subspace reverse correlation, the orientation-time perceptive field (PF) for the atypical grating detection task was derived for each participant. Detailed comparisons were made between the PFs measured with the amblyopic and healthy eyes. Results: The PF of the amblyopic eyes showed significant differences in orientation and time domain compared with that of the normal eyes (cluster-based permutation test, ps < 0.05), with broader bandwidth of orientation tuning (31.41 ± 10.59 degrees [mean ± SD] vs. 24.76 ± 6.85 degrees, P = 0.039) and delayed temporal dynamics (483 ± 68 ms vs. 425 ± 58 ms, P = 0.015). None of the altered PF properties correlated with the contrast sensitivity at 1 cycle per degree (c/deg) in amblyopia. No difference in PFs between the dominant and non-dominant eyes in the healthy group was found. Conclusions: The altered orientation-time PF to the low spatial frequency and high contrast stimuli suggests amblyopes had coarser orientation selectivity and prolonged reaction time. The broader orientation tuning probably reflects the abnormal lateral interaction in the primary visual cortex, whereas the temporal delay might indicate a high level deficit.


Assuntos
Ambliopia , Sensibilidades de Contraste , Olho , Humanos , Tempo de Reação , Acuidade Visual
8.
Chemosphere ; 291(Pt 2): 132875, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34774911

RESUMO

The wastewater treatment industry in urban China generally faces certain common problems. To provide a comprehensive analysis on common problems of the wastewater treatment industry, survey data from 467 wastewater treatment plants (WWTPs) and field investigation reports of 38 WWTPs were analyzed. The research results showed that, the common problems of the wastewater treatment industry are mainly concentrated in WWTPs and the drainage system. The length of per capita drainage networks is insufficient, only 0.85 m; approximately 63.17% WWTPs have hydraulic load rates (HLRs) are greater than 80%, and the ratio of water quality between the design value and actual value is approximately 0.7; and there is still a considerable gap in construction of wastewater treatment facilities compared to those in developed countries. These are still major common problems perplexing the wastewater treatment industry in urban China. In this study, the common problems that hinder improving the operation efficiency of WWTPs were investigated, the causes of the discrepancy were analyzed, and three countermeasures, such as refinement design, optimization facilities and reasonable process control were jointly explored to solve them. This study may provide valuable insights and methods for the wastewater treatment industry to effectively address the discrepancy between the design and actual operation of WWTPs.


Assuntos
Eliminação de Resíduos Líquidos , Purificação da Água , China , Águas Residuárias/análise
9.
Front Neurosci ; 15: 673491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149348

RESUMO

PURPOSE: Amblyopia affects not only spatial vision but also temporal vision. In this study, we aim to investigate temporal processing deficits in amblyopia. METHODS: Twenty amblyopic patients (age: 27.0 ± 5.53 years, 15 males), and 25 normal observers (age: 25.6 ± 4.03 years, 15 males) were recruited in this study. Contrast thresholds in an orientation discrimination task in five target-mask stimulus onset asynchronies (SOA) conditions (16.7 ms, 33.4 ms, 50.0 ms, 83.4 ms, and ∞/no noise) were measured. An elaborated perceptual template model (ePTM) was fit to the behavioral data to derive the temporal profile of visual processing for each participant. RESULTS: There were significant threshold differences between the amblyopic and normal eyes [F(1,43) = 10.6, p = 0.002] and a significant group × SOA interaction [F(2.75,118) = 4.98, p = 0.004], suggesting different temporal processing between the two groups. The ePTM fitted the data well (χ 2 test, all ps > 0.50). Compared to the normal eye, the amblyopic eye had a lower template gain (p = 0.046), and a temporal window with lower peak and broader width (all ps < 0.05). No significant correlation was found between the observed temporal deficits and visual acuity in amblyopia (ps > 0.50). Similar results were found in the anisometropic amblyopia subgroup. No significant difference was found between the fellow eyes of the monocular amblyopia and the normal eyes. CONCLUSION: Amblyopia is less efficient in processing dynamic visual stimuli. The temporal deficits in amblyopia, represented by a flattened temporal window, are likely independent of spatial vision deficits.

10.
Sci Rep ; 11(1): 2038, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33479480

RESUMO

Anaerobic ammonium oxidation (anammox) bacteria significantly improve the efficiency and reduce cost of nitrogen removal in wastewater treatment plants. However, their slow growth and vulnerable activity limit the application of anammox technology. In this paper, the enhancement of biotin on the nitrogen removal activity of anammox bacteria in short-term batch experiments was studied. We found that biotin played a significant role in promoting anammox activity within a biotin concentration range of 0.1-1.5 mg/L. At a biotin concentration of 1.0 mg/L, the total nitrogen removal rate (NRR) increased by 112%, extracellular polymeric substance (EPS) secretion and heme production significantly improved, and anammox bacterial biomass increased to maximum levels. Moreover, the predominant genus of anammox bacteria was Candidatus Brocadia.


Assuntos
Bactérias Anaeróbias/efeitos dos fármacos , Biotina/farmacologia , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Nitrogênio/química , Compostos de Amônio/metabolismo , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Matriz Extracelular de Substâncias Poliméricas/efeitos dos fármacos , Heme/biossíntese , Humanos , Nitrogênio/toxicidade , Oxirredução , Águas Residuárias/química , Águas Residuárias/toxicidade
11.
Environ Sci Pollut Res Int ; 23(21): 21451-21459, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27507143

RESUMO

The effect of no-tillage (NT) on rice yield and nitrogen (N) behavior often varies considerably from individual studies. A meta-analysis was performed to assess quantitatively the effect of NT on rice yield and N uptake by rice, N use efficiency (NUE, i.e., fertilizer N recovery efficiency), and nutrient runoff losses. We obtained data from 74 rice-field experiments reported during the last three decades (1983-2013). Results showed the NT system brought a reduction of 3.8 % in the rice yield compared with conventional tillage (CT). Soil pH of 6.5-7.5 was favorable for the improvement of rice yield with the NT system, while a significant negative NT effect on rice yield was observed in sandy soils (p < 0.05). N rate, ranging from 120 to 180 kg N ha-1, for at least 3 years was necessary for NT to enable rice yield comparable with that of CT. Furthermore, the observations indicated NT reduced N uptake and NUE of the rice by 5.4 and 16.9 %, while increased the N and P exports via runoff by 15.4 and 40.1 % compared with CT, respectively. Seedling cast transplantation, N rate within the range 120-180 kg N ha-1, and employing NT for longer than 3 years should be encouraged to compromise between productivity and environmental effects of NT implementation in rice fields.


Assuntos
Agricultura/métodos , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Poluentes Químicos da Água/análise , Fertilizantes/análise
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