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1.
J Vis ; 22(12): 1, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36318192

RESUMO

Previous work has claimed that canonical viewpoints of objects are more readily perceived than noncanonical viewpoints. However, all of these studies required participants to identify the object, a late perceptual process at best and arguably a cognitive process (Pylyshyn, 1999). Here, we extend this work to early vision by removing the explicit need to identify the objects. In particular, we asked participants to make an intact/scrambled discrimination of briefly presented objects that were viewed from either typical or atypical viewpoints. Notably, participants did not have to identify the object; only discriminate it from noise (scrambled). Participants were more sensitive in discriminating objects presented in typically encountered orientations than when objects were presented in atypical depth rotations (Experiment 1). However, the same effect for objects presented in atypical picture plane rotations (as opposed to typical ones) did not reach statistical significance (Experiments 2 and 3), suggesting that particular informative views may play a critical role in this effect. We interpret this enhanced perceptibility, for both these items and good exemplars and probable scenes, as deriving from their high real-world statistical regularity.


Assuntos
Orientação , Humanos
2.
Gerontology ; 65(4): 441-450, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30844813

RESUMO

BACKGROUND: With global aging, robots are considered a promising solution for handling the shortage of aged care and companionships. However, these technologies would serve little purpose if their intended users do not accept them. While the socioemotional selectivity theory predicts that older adults would accept robots that offer emotionally meaningful relationships, selective optimization with compensation model predicts that older adults would accept robots that compensate for their functional losses. OBJECTIVE: The present study aims to understand older adults' expectations for robots and to compare older adults' acceptance ratings for 2 existing robots: one of them is a more human-like and more service-oriented robot and the other one is a more animal-like and more companion-oriented robot. METHODS: A mixed methods study was conducted with 33 healthy, community-dwelling Taiwanese older adults (age range: 59-82 years). Participants first completed a semi-structured interview regarding their ideal robot. After receiving information about the 2 existing robots, they then completed the Unified Theory of Acceptance and Use of Technology questionnaires to report their pre-implementation acceptance of the 2 robots. RESULTS: Interviews were transcribed for conventional content analysis with satisfactory inter-rater reliability. From the interview data, a collection of older adults' ideal robot characteristics emerged with highlights of humanlike qualities. From the questionnaire data, respondents showed a higher level of acceptance toward the more service-oriented robot than the more companion-oriented robot in terms of attitude, perceived adaptiveness, and perceived usefulness. From the mixed methods analyses, the finding that older adults had a higher level of positive attitude towards the more service-oriented robot than the more companion-oriented robot was predicted by higher expectation or preference for robots with more service-related functions. CONCLUSION: This study identified older adults' preference toward more functional and humanlike robots. Our findings provide practical suggestions for future robot designs that target the older population.


Assuntos
Atividades Cotidianas , Atitude , Robótica , Apoio Social , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vida Independente , Masculino , Pessoa de Meia-Idade , Teoria Psicológica , Pesquisa Qualitativa , Taiwan , Tecnologia
3.
J Environ Manage ; 248: 109303, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466180

RESUMO

The application of flue gas desulfurization (FGD) gypsum has been recognized as a feasible measure in enhancing the quality of sodic soils. Quantitative evaluation of the effects of FGD gypsum on three-dimension (3D) pore characteristics is beneficial for understanding the reclamation mechanism of FGD gypsum on sodic soils. We collected intact soil cores from a sodic field at four depths (0-10, 10-20, 20-40, and 40-60 cm) in northern China to reconstruct 3D pore structures using X-ray computed tomography (CT), thus quantifying the effects of FGD gypsum (10.1 and 14.5 t hm-2) and leaching water (1520 and 2200 t hm-2) on the 3D pore characteristics and related soil physical properties. The treatments using FGD gypsum with leaching water promoted the formation of new pores and significantly (p < 0.05) increased the 3D image-based macroporosity, mesoporosity, total pore length, and number of nodes at depths of 0-20 cm, improving the permeability of sodic soils investigated, which is validated by the enhanced saturated hydraulic conductivity (Ksat). Irrigation water of 1520 t hm-2 is demonstrated effective in assisting FGD gypsum dissolution and leaching, but excessive leaching water (2200 t hm-2) may reduce the permeability of 20-40 cm depth. The combined application of 14.5 t hm-2 FGD gypsum and 1520 t hm-2 leaching water is suggested to obtain the optimal result for the investigated sodic soils. This study offers an applicable strategy for sodic soils reclamation and provides a reference for revealing the improvement mechanism of sodic soils by FGD gypsum and leaching water.


Assuntos
Sulfato de Cálcio , Solo , China , Conservação dos Recursos Naturais , Água
4.
Environ Sci Technol ; 52(4): 1695-1703, 2018 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-29361228

RESUMO

To monitor and manage hydrological pollution effectively, tracing sources of pollutants is of great importance and also is in urgent need. A variety of tracers have been developed such as isotopes, silica, bromide, and dyes; however, practical limitations of these traditional tracers still exist such as lack of multiplexed, multipoint tracing and interference of background noise. To overcome these limitations, a new tracing system based on DNA nanomaterials, namely DNA tracer, has already been developed. DNA tracers possess remarkable advantages including sufficient species, specificity, environmental friendly, stable migration, and high sensitivity as well as allowing for multipoints tracing. In this review article, we introduce the molecular design, synthesis, protection and signal readout strategies of DNA tracers, compare the advantages and disadvantages of DNA tracer with traditional tracers, and summarize the-state-of-art applications in hydrological environment investigations. In the end, we provide our perspective on the future development of DNA tracers.


Assuntos
Poluentes Ambientais , Hidrologia , DNA , Isótopos
5.
Cogn Affect Behav Neurosci ; 17(5): 954-972, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28681130

RESUMO

Previous studies found that word meaning can be processed unconsciously. Yet it remains unknown whether temporally segregated words can be integrated into a holistic meaningful phrase without consciousness. The first four experiments were designed to examine this by sequentially presenting the first three words of Chinese four-word idioms as prime to one eye and dynamic Mondrians to the other (i.e., the continuous flash suppression paradigm; CFS). An unmasked target word followed the three masked words in a lexical decision task. Results from such invisible (CFS) condition were compared with the visible condition where the preceding words were superimposed on the Mondrians and presented to both eyes. Lower performance in behavioral experiments and larger N400 event-related potentials (ERP) component for incongruent- than congruent-ending words were found in the visible condition. However, no such congruency effect was found in the invisible condition, even with enhanced statistical power and top-down attention, and with several potential confounding factors (contrast-dependent processing, long interval, no conscious training) excluded. Experiment 5 demonstrated that familiarity of word orientation without temporal integration can be processed unconsciously, excluding the possibility of general insensitivity of our paradigm. The overall result pattern therefore suggests that consciousness plays an important role in semantic temporal integration in the conditions we tested.


Assuntos
Córtex Cerebral/fisiologia , Estado de Consciência/fisiologia , Potenciais Evocados/fisiologia , Idioma , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Eletroencefalografia , Humanos , Mascaramento Perceptivo/fisiologia , Semântica , Fatores de Tempo , Adulto Jovem
6.
J Biopharm Stat ; 26(1): 37-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26366624

RESUMO

There are several challenging statistical problems identified in the regulatory review of large cardiovascular (CV) clinical outcome trials and central nervous system (CNS) trials. The problems can be common or distinct due to disease characteristics and the differences in trial design elements such as endpoints, trial duration, and trial size. In schizophrenia trials, heavy missing data is a big problem. In Alzheimer trials, the endpoints for assessing symptoms and the endpoints for assessing disease progression are essentially the same; it is difficult to construct a good trial design to evaluate a test drug for its ability to slow the disease progression. In CV trials, reliance on a composite endpoint with low event rate makes the trial size so large that it is infeasible to study multiple doses necessary to find the right dose for study patients. These are just a few typical problems. In the past decade, adaptive designs were increasingly used in these disease areas and some challenges occur with respect to that use. Based on our review experiences, group sequential designs (GSDs) have borne many successful stories in CV trials and are also increasingly used for developing treatments targeting CNS diseases. There is also a growing trend of using more advanced unblinded adaptive designs for producing efficacy evidence. Many statistical challenges with these kinds of adaptive designs have been identified through our experiences with the review of regulatory applications and are shared in this article.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Fármacos do Sistema Nervoso Central/uso terapêutico , Doenças do Sistema Nervoso Central/tratamento farmacológico , Fármacos Cardiovasculares/efeitos adversos , Fármacos Cardiovasculares/farmacologia , Fármacos do Sistema Nervoso Central/efeitos adversos , Fármacos do Sistema Nervoso Central/farmacologia , Ensaios Clínicos como Assunto , Humanos , Projetos de Pesquisa , Resultado do Tratamento
7.
Odontology ; 103(1): 84-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24174163

RESUMO

Maximum mouth opening (MMO) can reflect the function of the dentofacial musculature and joint system, and routine oral examinations should include its assessment. To diagnose abnormalities using MMO measurements, it is necessary to establish the normal range of MMO; however, few studies have investigated this subject in Taiwan. Therefore, the purposes of this study were to determine the normal MMO range in 3- to 5-year-old preschool children and to investigate the factors correlated with MMO. We examined the interincisal distance, defined as the distance between the edges of the upper and lower incisors, in 518 preschool children (age range 3-5 years; 271 boys and 247 girls) with a plastic sliding caliper. The MMO on both sides of the mouth and mouth width (MW) was measured 3 times. No differences in MMO were found between the genders. The interincisal distance was 37.47 (±4.11) mm for boys and 36.93 (±3.85) mm for girls, whereas the mean MMO was 37.21 (±3.99) mm. The MMO increased with the increasing age of the children, and the mean value of MMO in children aged 3, 4, and 5 was 35.31 (±4.03), 36.61 (±3.79), and 38.31 (±3.88) mm, respectively. Furthermore, MMO was found to correlate with weight and MW. MMO increased by 0.19 mm per increased weight and 0.37 mm per increased MW. The mean value of MMO in 3- to 5-year-old preschool children was 37.21 (±3.99) mm. MMO in 3- to 5-year-old preschool children increased with age and was correlated with weight and MW.


Assuntos
Artrometria Articular/métodos , Boca/fisiologia , Amplitude de Movimento Articular/fisiologia , Pré-Escolar , Feminino , Humanos , Masculino , Taiwan
8.
J Sep Sci ; 37(15): 1911-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24830747

RESUMO

A simple, easy and economical approach for the preparation of a hybrid carbon/silica monolithic capillary column was described for the first time by using silica monolith as framework in combination with hydrothermal carbonization at 180°C. During the preparation process, formamide was introduced to the reaction solutions to reduce the dissolution rate of monolithic silica skeleton and its optimal concentration was 1.5 M. Fourier transform infrared spectrometry, scanning electron microscopy, energy dispersive X-ray spectrometry, and inverse size exclusion chromatography were carried out to characterize the as-prepared column. The results demonstrated that carbon spheres ranging from 150 to 1000 nm were successfully attached to the surface of silica skeleton. The prepared hybrid carbon/silica column had a permeability of 4.4 × 10(-14) m(2). Chromatographic performance of the column was evaluated by separation of various compounds including alkylbenzenes, nucleosides and bases, and aromatic acids. The column exhibited an efficiency of 75,000 plates/m for butylbenzene at the optimal linear velocity of 0.23 mm/s. The successful separation of these compounds and the study on mechanism indicated that the column can be applied in mixed-mode chromatography.

9.
J Biopharm Stat ; 24(5): 1059-72, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24915027

RESUMO

Adaptive designs have generated a great deal of attention to clinical trial communities. The literature contains many statistical methods to deal with added statistical uncertainties concerning the adaptations. Increasingly encountered in regulatory applications are adaptive statistical information designs that allow modification of sample size or related statistical information and adaptive selection designs that allow selection of doses or patient populations during the course of a clinical trial. For adaptive statistical information designs, a few statistical testing methods are mathematically equivalent, as a number of articles have stipulated, but arguably there are large differences in their practical ramifications. We pinpoint some undesirable features of these methods in this work. For adaptive selection designs, the selection based on biomarker data for testing the correlated clinical endpoints may increase statistical uncertainty in terms of type I error probability, and most importantly the increased statistical uncertainty may be impossible to assess.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Modelos Estatísticos , Projetos de Pesquisa , Ensaios Clínicos como Assunto/métodos , Interpretação Estatística de Dados , Humanos , Variações Dependentes do Observador , Tamanho da Amostra , Resultado do Tratamento
10.
ScientificWorldJournal ; 2014: 805342, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24757438

RESUMO

The effect of gypsum on the physical and chemical characteristics of sodic soils is nonlinear and controlled by multiple factors. The support vector machine (SVM) is able to solve practical problems such as small samples, nonlinearity, high dimensions, and local minima points. This paper reports the use of the SVM regression method to predict changes in the chemical properties of sodic soils under different gypsum application rates in a soil column experiment and to evaluate the effect of gypsum reclamation on sodic soils. The research results show that (1) the SVM soil solute transport model using the Matlab toolbox represents the change in Ca(2+) and Na(+) in the soil solution and leachate well, with a high prediction accuracy. (2) Using the SVM model to predict the spatial and temporal variations in the soil solute content is feasible and does not require a specific mathematical model. The SVM model can take full advantage of the distribution characteristics of the training sample. (3) The workload of the soil solute transport prediction model based on the SVM is greatly reduced by not having to determine the hydrodynamic dispersion coefficient and retardation coefficient, and the model is thus highly practical.


Assuntos
Sulfato de Cálcio , Transporte de Íons , Solo , Máquina de Vetores de Suporte
11.
Heliyon ; 10(9): e30131, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38707430

RESUMO

Utilizing city-level data from China, the paper employs a spatial econometric analysis to investigate the impact of fiscal decentralization on urban pollution. Empirical evidence indicates: (1) In the context of the emphasis of ecological civilization construction in China, an increase of fiscal autonomy for local governments is conducive to mitigating urban pollution intensity. Specifically, fiscal decentralization in one city not only promotes a reduction in local pollution intensity but alleviates environmental pollution problems in adjacent cities through spatial spillover effects. (2) Industrial structure upgrading and green technology progress become crucial measures for local governments to realize pollution reduction targets through fiscal expenditure. (3) Heterogeneity analysis reveals that the positive significance of decentralization is most prominent in the eastern China, while local governments with fiscal autonomy in central region tend to transfer pollution to neighboring cities. (4) There is a threshold characteristic for fiscal decentralization to promote a reduction in urban pollution intensity, and its marginal effect becomes more significant accompanied by continuous introduction of sophisticated foreign direct investment. Finally, the paper summarizes the potential significance of fiscal decentralization among Chinese local governments against the background of "Chinese-style decentralization" and proposes corresponding policy recommendations.

12.
Environ Sci Pollut Res Int ; 31(6): 9062-9077, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182959

RESUMO

Based on the panel data of 259 cities across China from 2011 to 2019, the study investigates the long-run impact of digital economy on regional pollution intensity by employing multiple models. The estimation results reveal that (1) the relatively heavily polluted areas are concentrated in the north, especially in the northeast of China; the overall pollution intensity is decreasing year by year at the national level; (2) the development of digital economy can significantly contribute to the reduction of regional pollution intensity and it has a statistically significant negative spatial spillover effect on the pollution intensity of neighboring cities; (3) mechanism analysis shows that the development of digital economy not only has a direct effect on the reduction of pollution intensity but also promotes the reduction through the channel of industrial structure upgrading and green technology progress; (4) the results of threshold model suggest that as the level of development of the digital economy increases, its marginal inhibitory effect of promoting the decrease in pollution intensity will diminish; (5) heterogeneity analysis shows that the development of digital economy makes the strongest marginal contribution to pollution intensity reduction in the northeast region. Finally, the conclusions remain valid after controlling for exogenous shocks such as "smart city" policy, various robustness, and endogeneity tests.


Assuntos
Poluição Ambiental , Indústrias , China , Cidades , Políticas , Desenvolvimento Econômico
13.
J Sep Sci ; 36(9-10): 1516-23, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23495254

RESUMO

Dopamine is easy to self-polymerize under alkaline conditions and the resultant polydopamine is easy to adhere to the surface of many organic and inorganic materials. Based on the characteristics of dopamine, in this paper, a new polydopamine functionalized monolithic silica column was successfully prepared for performing mixed-mode chromatography. The performance of the column was evaluated by the separation of different types of samples including alkylbenzenes, polycyclic aromatic hydrocarbons, aromatic acids, phenols, and bases. The mechanism for the separation of these compounds was studied and appeared to involve the mixed interactions containing π-π, hydrophobic, electrostatic, and hydrophilic interactions.


Assuntos
Cromatografia/métodos , Indóis/química , Polímeros/química , Adsorção , Cromatografia/instrumentação , Interações Hidrofóbicas e Hidrofílicas , Dióxido de Silício/química
14.
Atten Percept Psychophys ; 85(4): 1127-1149, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37014611

RESUMO

The current study aims to explore one factor that likely contributes to these statistical regularities, familiarity. Are highly familiar stimuli perceived more readily? Previous work showing effects of familiarity on perception have used recognition tasks, which arguably tap into post-perceptual processes. Here we use a perceptual task that does not depend on explicit recognition; participants were asked to discriminate whether a rapidly presented image was intact or scrambled. The familiarity level of stimuli was manipulated. Results show that famous or upright orientated logos (Experiments 1 and 2) or faces (Experiment 3) were better discriminated than novel or inverted logos and faces. To further dissociate our task from recognition, we implemented a simple detection task (Experiment 4) and directly compared the intact/scrambled task to a recognition task (Experiment 5) on the same set of faces used in Experiment 3. The fame and orientation familiarity effect were still present in the simple detection task, and the duration needed on the intact/scrambled task was significantly less than the recognition task. We conclude that familiarity effect demonstrated here is not driven by explicit recognition and instead reflects a true perceptual effect.


Assuntos
Face , Reconhecimento Psicológico , Humanos , Orientação Espacial , Reconhecimento Visual de Modelos
15.
Environ Sci Pollut Res Int ; 30(11): 30672-30691, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36441313

RESUMO

Industry dominates energy consumption and carbon emissions in China, and industrial energy efficiency is critical for the achievement of energy transformation and carbon emission reduction. With the rapid development of the digital economy, its impact on energy efficiency is gradually emerging, and it is necessary to clarify the influencing mechanism on industrial energy efficiency. Based on the panel data of industrial sectors in 41 cities in the Yangtze River Delta from 2011 to 2019, the main objectives of this study are to more accurately measure the industrial total factor energy efficiency in each city by using the Super-Dynamic-SBM model. It analyses the influence mechanism of the digital economy and other influencing factors on industrial total factor energy efficiency with different methods. The research results indicate that, first, the total factor energy efficiency of the industrial sector in the Yangtze River Delta urban agglomeration generally showed a steady upward trend. Second, the digital economy and environmental regulation play a significant role in promoting total factor energy efficiency. In addition, industrial energy efficiency and the digital economy show an inverted "U" shaped relationship. With the improvement of the digital economy, its marginal contribution to total factor energy efficiency gradually weakens. Finally, technological progress is an important transmission channel for the impact of the digital economy on total factor energy efficiency.


Assuntos
Conservação de Recursos Energéticos , Rios , Cidades , China , Desenvolvimento Econômico , Eficiência , Carbono/análise
16.
Microorganisms ; 11(6)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37375068

RESUMO

Swarming regulation is complicated in flagellated bacteria, especially those possessing dual flagellar systems. It remains unclear whether and how the movement of the constitutive polar flagellum is regulated during swarming motility of these bacteria. Here, we report the downregulation of polar flagellar motility by the c-di-GMP effector FilZ in the marine sedimentary bacterium Pseudoalteromonas sp. SM9913. Strain SM9913 possesses two flagellar systems, and filZ is located in the lateral flagellar gene cluster. The function of FilZ is negatively controlled by intracellular c-di-GMP. Swarming in strain SM9913 consists of three periods. Deletion and overexpression of filZ revealed that, during the period when strain SM9913 expands quickly, FilZ facilitates swarming. In vitro pull-down and bacterial two-hybrid assays suggested that, in the absence of c-di-GMP, FilZ interacts with the CheW homolog A2230, which may be involved in the chemotactic signal transduction pathway to the polar flagellar motor protein FliMp, to interfere with polar flagellar motility. When bound to c-di-GMP, FilZ loses its ability to interact with A2230. Bioinformatic investigation indicated that filZ-like genes are present in many bacteria with dual flagellar systems. Our findings demonstrate a novel mode of regulation of bacterial swarming motility.

17.
Sci Adv ; 9(3): eadd8659, 2023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36662863

RESUMO

Braun's lipoprotein (Lpp) plays a major role in stabilizing the integrity of the cell envelope in Escherichia coli, as it provides a covalent cross-link between the outer membrane and the peptidoglycan layer. An important challenge in elucidating the physiological role of Lpp lies in attaining a detailed understanding of its distribution on the peptidoglycan layer. Here, using atomic force microscopy, we visualized Lpp directly on peptidoglycan sacculi. Lpp is homogeneously distributed over the outer surface of the sacculus at a high density. However, it is absent at the constriction site during cell division, revealing its role in the cell division process with Pal, another cell envelope-associated protein. Collectively, we have established a framework to elucidate the distribution of Lpp and other peptidoglycan-bound proteins via a direct imaging modality.


Assuntos
Escherichia coli , Lipoproteínas , Microscopia de Força Atômica , Imagem Molecular , Proteínas da Membrana Bacteriana Externa/metabolismo , Membrana Celular/metabolismo , Escherichia coli/química , Lipoproteínas/química , Peptidoglicano/química , Imagem Molecular/métodos
18.
J Biopharm Stat ; 21(2): 326-41, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21391005

RESUMO

In longitudinal clinical studies, after randomization at baseline, subjects are followed for a period of time for development of symptoms. A mixed model for repeated measures (MMRM) can be used to analyze data from such studies. Fitzmaurice et al. (2004) outlined five approaches for handling baseline responses in an MMRM analysis. They are: (1) Retain the baselines as part of the outcome vector and make no assumptions about group differences in the mean response at baseline. (2) Retain the baselines as part of the outcome vector and assume the group means are equal at baseline. (3) Subtract the baselines from all of the remaining post-baseline responses, and analyze the differences from baseline. (4) Use the baselines as a covariate in the analysis of the post-baseline responses, assuming homogeneous regression slopes. (5) Use the baselines as a covariate in the analysis of the post-baseline responses, allowing different regression slopes. In this paper, we evaluate these five approaches in the presence of data missing at random. We evaluate the approaches based on the bias of the estimate and the coverage accuracy of the confidence interval. The results suggest that strategies 2 and 5 are recommended.


Assuntos
Interpretação Estatística de Dados , Ensaios Clínicos Controlados Aleatórios como Assunto , Simulação por Computador , Humanos , Estudos Longitudinais , Pacientes Desistentes do Tratamento
20.
PeerJ ; 9: e11674, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34322320

RESUMO

BACKGROUND: Di-nitrogen oxide (N2O) emissions from soil may lead to nonpoint-source pollution in farmland. Improving the C and N content in the soil is an excellent strategy to reduce N2O emission and mitigate soil N loss. However, this method lacks a unified mathematical index or standard to evaluate its effect. METHODS: To quantify the impact of soil improvement (C and N) on N2O emissions, we conducted a 2-year field experiment using biochar as carbon source and fertilizer as nitrogen source, setting three treatments (fertilization (300 kg N ha-1), fertilization + biochar (30 t ha-1), control). RESULTS: Results indicate that after biochar application, the average soil water content above 20 cm increased by ∼26% and 26.92% in 2019, and ∼10% and 12.49% in 2020. The average soil temperature above 20 cm also increased by ∼2% and 3.41% in 2019. Fertigation significantly promotes the soil N2O emissions, and biochar application indeed inhibited the cumulation by approximately 52.4% in 2019 and 33.9% in 2020, respectively. N2O emissions strongly depend on the deep soil moisture and temperature (20-80 cm), in addition to the surface soil moisture and temperature (0-20 cm). Therefore, we established an exponential model between the soil moisture and N2O emissions based on theoretical analysis. We find that the N2O emissions exponentially increase with increasing soil moisture regardless of fertilization or biochar application. Furthermore, the coefficient a < 0 means that N2O emissions initially increase and then decrease. The aRU < aCK indicates that fertilization does promote the rate of N2O emissions, and the aBRU > aRU indicates that biochar application mitigates this rate induced by fertilization. This conclusion can be verified by the sensitivity coefficient (SCB of 1.02 and 14.74; SCU of 19.18 and 20.83). Thus, we believe the model can quantify the impact of soil C and N changes on N2O emissions. We can conclude that biochar does significantly reduce N2O emissions from farmland.

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