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Microbial-driven N turnover is important in regulating N fertilizer use efficiency through the secretion of metabolites like glycolipids. Currently, our understanding of the potential of glycolipids to partially reduce N fertilizer use and the effects of glycolipids on crop yield and N use efficiency is still limited. Here, a three-year in situ field experiment was conducted with seven treatments: no fertilization (CK); chemical N, phosphorus and potassium (NPK); NPK plus glycolipids (N+PKT); and PK plus glycolipids with 10% (0.9 N+PKT), 20% (0.8 N+PKT), 30% (0.7 N+PKT), and 100% (PKT) N reduction. Compared with NPK, glycolipids with 0-20% N reduction did not significantly reduce maize yields, and also increased N uptake by 6.26-11.07%, but no significant changes in grain or straw N uptake. The N resorption efficiency under 0.9 N+PKT was significantly greater than that under NPK, while the apparent utilization rates of N fertilizer and partial factor productivity of N under 0.9 N+PKT were significantly greater than those under NPK. Although 0.9 N+PKT led to additional labor and input costs, compared with NPK, it had a greater net economic benefit. Our study demonstrates the potential for using glycolipids in agroecosystem management and provides theoretical support for optimizing fertilization strategies.
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Cucumber wilt is an important soil borne disease in cucumber production, which seriously affects the development of the cucumber industry. Cleome spinosa also has pharmacological effects such as antibacterial, analgesic, anti-inflammatory, and insect repellent. To study the control effect and mechanism of Cleome spinosa fumigation on cucumber wilt disease, different concentrations of Cleome spinosa fragments were applied on cucumber plants infected with Fusarium oxysporum. Cleome spinosa fumigation significantly reduced the incidence rate of cucumber Fusarium wilt. Under the fumigation treatment of 7.5 g kg-1 Cleome spinosa fragments, the preventive effects were 74.7%. Cleome spinosa fragments fumigation can promote cucumber growth and synthesis of photosynthetic pigments, thereby improving individual plant yield and fruit quality. At 7.5 g kg-1 Cleome spinosa fragments fumigation treatment, the plant height and individual plant yield of cucumber increased by 20.3% and 34.3%, respectively. Cleome spinosa fumigation can enhance the activity of antioxidant enzymes in cucumber, maintain a balance of reactive oxygen species metabolism, and enhance the plant disease resistance. Moreover, Cleome spinosa can also regulate the activities of Mg2+-ATPase and Ca2+-ATPase, enhancing its resistance to Fusarium oxysporum. Moreover, number of bacteria and fungi significantly decreased under Cleome spinosa fumigation. Those results suggested that Cleome spinosa could effectively restrain cucumber Fusarium wilt. This study will provide a new idea for the further use of biological fumigation to prevent soil-borne diseases.
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Fusarium oxysporum is a soil-borne plant pathogen that can cause various plant diseases including cucumber wilt. An experiment was conducted to explore the physiological mechanism underlying the inhibitory activity of Cleome spinosa against the morphology and reproduction of F. oxysporum. Different concentrations of C. spinosa extracts. -0 (Z0), 5 (Z5), 15 (Z15), 30 (Z30), 45 (Z45), and 60 (Z60) mg·mL-1 were applied to F. oxysporum. Cleome spinosa extract significantly reduced the colony diameter (89.7 %) and dry mass (78.9 %) of F. oxysporum under the Z45 treatment. Moreover, spore formation was also significantly inhibited by C. spinosa extract. The spore number and germination rate decreased by 73.5 % and 83.0 %, respectively, under the Z45 treatment. The number of mycelia in the unit field of view was significantly reduced, and the mycelia were wizened with rough surfaces and more bends under the Z45 treatment. Hence, C. spinosa extracts severely damaged the morphology of F. oxysporum mycelia. Additionally, F. oxysporum could not adjust to the osmotic changes caused by C. spinosa extract, leading to membrane injury and electrolyte leakage. Finally, they impaired the antioxidant system in F. oxysporum, resulting in cell membrane injury.
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Critical processing protocols of industrial bimetallic composite ionic liquid (IL) are necessary to assure good mass transfer rates for process optimization and efficient metal recovery. Here, the effects of different conditions on the electrochemical behavior and copper recovery from the industrial bimetallic composite IL are crucial for effective resource utilization. Cyclic voltammetry (CV) shows that the reduction of Cu(I) to Cu(0) during the cathodic reduction region is the irreversible diffusion-controlled process, and the diffusion coefficient increased with temperature which indicated that increasing temperature could promote the diffusion and mass transfer. During electrodeposition, metallic copper is obtained exclusively on the cathode, while CuCl2 accumulates exclusively on the anode. Scanning electron microscopy shows that the micron-size electrodeposits become larger and significantly rougher with increasing temperature and ultrasonic frequency, illustrating that these factors hasten the nucleation and crystallization rates at high overpotentials. The efficiency of copper recovery is greatly improved by employing high temperature and ultrasonic cavitation, and the highest values correspond to r = 76.9% at 80 °C and r = 63.6% at 40 kHz. The study lays the foundation for efficient and rapid recovery of copper from spent ILs.
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Electrochemical mechanisms of molten salt electrolysis from TiO2 to titanium were investigated by Potentiostatic electrolysis, cyclic voltammetry, and square wave voltammetry in NaCl-CaCl2 at 800 °C. The composition and morphology of the product obtained at different electrolysis times were characterized by XRD and SEM. CaTiO3 phase was found in the TiO2 electrochemical reduction process. Electrochemical reduction of TiO2 to titanium is a four-step reduction process, which can be summarized as TiO2âTi4O7âTi2O3âTiOâTi. Spontaneous and electrochemical reactions take place simultaneously in the reduction process. The electrochemical reduction of TiO2âTi4O7âTi2O3âTiO affected by diffusion was irreversible.
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With the popularity of smartphones and the increasing dependence on cellphones, cellphone-use-involved distracted driving has become a global traffic safety concern. Calling, texting, or watching videos while driving could have harmful impacts on driving abilities and increase crash-injury severities. To investigate the temporal stability and the heterogeneity of cellphone-involved crash injury severity determinants, a series of likelihood ratio tests and random parameters logit models with heterogeneity in means and variances are estimated. Cellphone-involved single-vehicle crash datasets of Pennsylvania from 2004 to 2019 are utilized. Marginal effects are also applied to investigate the impact of explanatory variables on injury severity outcomes. The results indicate an overall temporal instability of cellphone-involved crashes across different periods. However, driving without seatbelts and overturns are observed to produce relatively stable and positive influence on the increased injury severities of cellphone-involved crashes. Besides, it is noteworthy that a combination of cellphone usage with risky driving behaviors (aggressive driving, alcohol- or drug-related driving, speeding, or fatigue driving) significantly increase driver injury-severities. This finding highlights the necessity of identifying drivers with multiple risk-taking behaviors and enacting laws to prohibit these drivers from using cellphones while driving. Applications of smartphones provide another feasible approach to prevent using cellphones while driving. Insights and suggestions of this study would be valuable to mitigate the negative outcomes of cellphone-involved crashes and prevent the crashes caused by cellphone-involved distracted driving in the future.
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Condução de Veículo , Uso do Telefone Celular , Telefone Celular , Direção Distraída , Ferimentos e Lesões , Acidentes de Trânsito/prevenção & controle , Uso do Telefone Celular/efeitos adversos , Direção Distraída/prevenção & controle , Humanos , Modelos Logísticos , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controleRESUMO
INTRODUCTION: With prevalent and increased attention to driver inattention (DI) behavior, this research provides a comprehensive investigation of the influence of built environment and roadway characteristics on the DI-related vehicle crash frequency per year. Specifically, a comparative analysis between DI-related crash frequency in rural road segments and urban road segments is conducted. METHOD: Utilizing DI-related crash data collected from North Carolina for the period 2013-2017, three types of models: (1) Poisson/negative binomial (NB) model, (2) Poisson hurdle (HP) model/negative binomial hurdle (HNB) model, and (3) random intercepts Poisson hurdle (RIHP) model/random intercepts negative binomial hurdle (RIHNB) model, are applied to handle excessive zeros and unobserved heterogeneity in the dataset. RESULTS: The results show that RIHP and RIHNB models distinctly outperform other models in terms of goodness-of-fit. The presence of commercial areas is found to increase the probability and frequency of DI-related crashes in both rural and urban regions. Roadway characteristics (such as non-freeways, segments with multiple lanes, and traffic signals) are positively associated with increased DI-related crash counts, whereas state-secondary routes and speed limits (higher than 35 mph) are associated with decreased DI-related crash counts in rural and urban regions. Besides, horizontal curved and longitudinal bottomed segments and segments with double yellow lines/no passing zones are likely to have fewer DI-related crashes in urban areas. Medians in rural road segments are found to be effective to reduce DI-related crashes. Practical Applications: These findings provide a valuable understanding of the DI-related crash frequency for transportation agencies to propose effective countermeasures and safety treatments (e.g., dispatching more police enforcement or surveillance cameras in commercial areas, and setting more medians in rural roads) to mitigate the negative consequences of DI behavior.
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Acidentes de Trânsito , Ambiente Construído , Planejamento Ambiental , Humanos , Modelos Estatísticos , Probabilidade , População RuralRESUMO
A novel Mo-Sn catalyst for the oxidative coupling of methane was designed using a hydrothermal method. At 650 °C, the conversion of methane was 8.6% and the selectivity of the C2 hydrocarbons reached as high as 98.1% over the Mo1Sn3 catalyst, with a CO2 selectivity of only 0.8%. We demonstrated that the deep oxidation of methane to CO2 was further inhibited due to the synergistic effects of moderately strong basic sites and reactive oxygen species on the catalyst surface.
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OBJECTIVES: Osteosarcoma (OS) is a type of bone malignancy. This study attempted to explore the effect of long non-coding RNA TTN-AS1 (TTN-AS1) on OS and to determine its molecular mechanisms. METHODS: The expression of TTN-AS1, microRNA-16-1-3p (miR-16-1-3p), and transcription factor activating enhancer binding protein 4 (TFAP4) in OS was assessed using qRT-PCR. The OS cell proliferation, migration, and invasion were measured using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wound-healing, and transwell assays. N-cadherin and MMP-2 protein level was determined with western blot. Interactions between TTN-AS1 and miR-16-1-3p or TFAP4 and miR-16-1-3p were confirmed using the dual-luciferase reporter assay. Additionally, an OS xenograft tumor model was constructed to assess the effect of TTN-AS1 on tumor growth. RESULTS: TTN-AS1 and TFAP4 expression was increased in OS, while miR-16-1-3p expression was decreased. TTN-AS1 silencing restrained OS cell proliferation, migration, invasion, N-cadherin and MMP-2 protein expression, and hindered tumor growth. MiR-16-1-3p overexpression retarded the malignant behavior of OS cells. TTN-AS1 played a carcinostatic role by down-regulating miR-16-1-3p in the OS cells. Moreover, miR-16-1-3p inhibition or TFAP4 elevation weakened the suppressive effect of TTN-AS1 silencing on OS cell tumor progression. CONCLUSION: TTN-AS1 promoted the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of OS cells via mediating the miR-16-1-3p/TFAP4 axis. TTN-AS1 may be a critical target for improving OS.
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Shared spaces are gaining popularity worldwide alongside the promotion of walking and cycling. Pedestrians, conventional bicycles, and electric bicycles (e-bikes) currently coexist in many shared spaces, with the prevalence of e-bikes increasing gradually in recent years. Shared spaces can provide a lower-stress experience for users because they are separated from motorized traffic, but frequent interactions among users raise safety concerns. This study sought to investigate conflict behaviours and characteristics among pedestrians, conventional bicycles, and e-bikes in shared spaces. Video data covering 12 h from three locations in Shenzhen city was analyzed. A total of 1748 pedestrians, 1748 conventional bicycles, and 930 e-bikes were observed, while 337 traffic conflicts were identified using the Dutch Objective Conflict Technique for Operation and Research (DOCTOR) method. Shared-space crash data recorded between April of 2013 and September of 2019 was used to validate and complement the conflict analysis. Friedman test was used to compare the conflict behaviours and characteristics among different groups. The analysis showed a positive relationship between the traffic volume and the number of conflicts but an inverse relationship between the traffic ratios and conflict ratios. Evasive actions, including swerving, decelerating, accelerating, and their combinations, were analyzed for various conflict types and severities, with swerving found to be the most common, especially in slight conflicts. Compared with slight conflicts, conventional bicycles and e-bikes exhibited low-speed characteristics in serious conflicts. These results indicated that high traffic volume and traffic complexity are the main factors that affect conflicts. It was proposed that the conflict coefficient be used to measure shared-space safety. In addition, the video observation study and crash data analysis suggested that conflicts and crashes between e-bikes and pedestrians are high-occurrence events, and that pedestrians are often exposed to higher injury risks.
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Ciclismo , Pedestres , Acidentes de Trânsito , Cidades , HumanosRESUMO
Quantum materials have attracted much attention in recent years due to their exotic and incredible properties. Among them, van der Waals materials stand out due to their weak interlayer coupling, providing easy access to manipulating electrical and optical properties. Many fascinating electrical, optical, and magnetic properties have been reported in the moiré superlattices, such as unconventional superconductivity, photonic dispersion engineering, and ferromagnetism. In this review, we summarize the methods to prepare moiré superlattices in the van der Waals materials and focus on the current discoveries of moiré pattern-modified electrical properties, recent findings of atomic reconstruction, as well as some possible future directions in this field.
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CuHY samples prepared by solid-state ion exchange of HY zeolite with CuCl were used as catalysts in isobutane/2-butene alkylation. The results show that both the addition amount of CuCl and the calcination temperature affect the ion exchange degree. Cu+ can be introduced into Y zeolite by replacing H+ in the HY zeolite after the solid-state ion exchange, causing a decrease of the amount of Brønsted acid sites and an increase of that of Lewis acid sites. When taking CuHY as the catalyst in isobutane/2-butene alkylation, the 3d104s0 valence electron configuration of Cu+ makes it favorable for inhibiting the oligomerization of 2-butene and accelerating the hydride transfer reaction rate by indirectly increasing the local isobutane/olefin ratio around the acid sites of the catalyst. As a result, the selectivity of C8 and trimethylpentanes over CuHY in alkylate are improved compared with those of HY.
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The recent observation of unusually high thermal conductivity exceeding 1000 W m-1 K-1 in single-crystal boron arsenide (BAs) has led to interest in the potential application of this semiconductor for thermal management. Although both the electron/hole high mobilities have been calculated for BAs, there is a lack of experimental investigation of its electronic properties. Here, a photoluminescence (PL) measurement of single-crystal BAs at different temperatures and pressures is reported. The measurements reveal an indirect bandgap and two donor-acceptor pair (DAP) recombination transitions. Based on first-principles calculations and time-of-flight secondary-ion mass spectrometry results, the two DAP transitions are confirmed to originate from Si and C impurities occupying shallow energy levels in the bandgap. High-pressure PL spectra show that the donor level with respect to the conduction band minimum shrinks with increasing pressure, which affects the release of free carriers from defect states. These findings suggest the possibility of strain engineering of the transport properties of BAs for application in electronic devices.
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PURPOSE: Osteosarcoma (OS) is a frequently occurring malignancy in children and adolescents. In this study, we aimed to investigate the effects of the long non-coding RNA (lncRNA) LINC00662 (LINC00662) in OS and the underlying molecular mechanism. METHODS: The expression of LINC00662, microRNA-15a-5p (miR-15a-5p), and Notch2 in OS was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation, migration, and invasion of OS cells were analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), wound-healing, and transwell assay. The interactions among LINC00662, miR-15a-5p, and Notch2 were determined by dual-luciferase reporter assays. A tumor xenograft model was established in mice for evaluating tumor growth in vivo. RESULTS: The expression of LINC00662 and Notch2 was found to be upregulated in OS, but the expression of miR-15a-5p was downregulated. The results demonstrated that LINC00662 knockdown attenuated the proliferation, migration, and invasion of OS cells and suppressed tumor growth in mice. The study further demonstrated that LINC00662 directly interacted with miR-15a-5p, and that Notch2 was a target of miR-15a-5p. The inhibition of miR-15a-5p or Notch2 overexpression markedly reversed the suppressive effect of sh-LINC00662 on the proliferation, migration, and invasion of OS cells. CONCLUSION: The study demonstrated that LINC00662 could be a potential biomarker for OS therapy, and LINC00662 knockdown suppressed the proliferation, migration, and invasion of OS cells by regulating the miR-15a-5p/Notch2 axis.
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Two distinct stacking orders in ReS2 are identified without ambiguity and their influence on vibrational, optical properties and carrier dynamics are investigated. With atomic resolution scanning transmission electron microscopy (STEM), two stacking orders are determined as AA stacking with negligible displacement across layers, and AB stacking with about a one-unit cell displacement along the a axis. First-principles calculations confirm that these two stacking orders correspond to two local energy minima. Raman spectra inform a consistent difference of modes I & III, about 13 cm-1 for AA stacking, and 20 cm-1 for AB stacking, making a simple tool for determining the stacking orders in ReS2 . Polarized photoluminescence (PL) reveals that AB stacking possesses blueshifted PL peak positions, and broader peak widths, compared with AA stacking, indicating stronger interlayer interaction. Transient transmission measured with femtosecond pump-probe spectroscopy suggests exciton dynamics being more anisotropic in AB stacking, where excited state absorption related to Exc. III mode disappears when probe polarization aligns perpendicular to b axis. The findings underscore the stacking-order driven optical properties and carrier dynamics of ReS2 , mediate many seemingly contradictory results in the literature, and open up an opportunity to engineer electronic devices with new functionalities by manipulating the stacking order.
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Wormlike micelles (WLMs) have been successfully constructed from many different C22-tailed surfactants. Here, we creatively introduced a bulky piperazine group onto a C22-tailed zwitterionic surfactant, N-erucamidopropyl-N,N-piperazine-N-methyl ammonium propanesulfonate (EDPS), and investigated the micellar structure and properties of the EDPS WLMs via molecular dynamics simulation, cryo-TEM and rheological techniques. It was found that 25 mM EDPS increased the zero-shear viscosity to as high as â¼106 mPa s. Furthermore, abnormal rheological behaviors, such as an inflection in the shear thinning region of steady rheology and an abrupt decrease of the shear stress at a critical shear rate, were observed, which was attributed to the unique ladder shape micellar structure. The EDPS WLMs were superior to other C22-tailed surfactants in many aspects, such as a low overlapping concentration, higher viscosity, stable viscosity over the whole pH range, and great temperature and salt (NaCl, CaCl2 and MgCl2) tolerance.
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Because of their weak interlayer bonding, van der Waals (vdW) solids are very sensitive to external stimuli such as strain. Experimental studies of strain tuning of thermal properties in vdW solids have not yet been reported. Under â¼9% cross-plane compressive strain created by hydrostatic pressure in a diamond anvil cell, we observed an increase of cross-plane thermal conductivity in bulk MoS_{2} from 3.5 to about 25 W m^{-1} K^{-1}, measured with a picosecond transient thermoreflectance technique. First-principles calculations and coherent phonon spectroscopy experiments reveal that this drastic change arises from the strain-enhanced interlayer interaction, heavily modified phonon dispersions, and decrease in phonon lifetimes due to the unbundling effect along the cross-plane direction. The contribution from the change of electronic thermal conductivity is negligible. Our results suggest possible parallel tuning of structural, thermal, and electrical properties of vdW solids with strain in multiphysics devices.
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In response to the rapid economic growth in China, its freeway system has become the longest in the world and likely will continue to expand. Unfortunately, the safety issues on freeways in China have grown as well and are of great concern to Chinese transportation authorities and drivers. While many proven safety countermeasures developed and implemented by other countries are available for reference, they may be not fully transferrable to China due to the differences in driving cultures and conditions. As a result, an investigation of China's unique safety factors and effective relevant countermeasures are urgently needed. The study presented in this paper thoroughly investigated the factors contributing to freeway crashes in China based on detailed crash data, traffic characteristics, freeway geometry, pavement conditions, and weather conditions. To properly account for the over-dispersion of data and unobserved heterogeneity, a random effects negative binomial (RENB) model and a random parameters negative binomial (RPNB) model were applied, along with a negative binomial (NB) model. The analysis revealed a large number of crash frequency factors, including several interesting and important factors rarely studied in the past, such as the safety effects of climbing lanes. Moreover, the RENB and RPNB models were found to considerably outperform the NB model; however, although the RPNB exhibited better goodness-of-fit than the RENB model, the difference was rather small. The findings of this study shed more light on the factors influencing freeway crashes in China. The results will be useful to highway designers and engineers for creating, building, and operating safe freeways as well as to safety management departments for developing effective safety countermeasures. The study presented in this paper also provides additional guidance for choosing relevant methods to analyze safety and to identify safety factors.
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Acidentes de Trânsito/estatística & dados numéricos , Condução de Veículo , Planejamento Ambiental , Segurança , Acidentes de Trânsito/prevenção & controle , China , Humanos , Modelos Estatísticos , Segurança/normas , Tempo (Meteorologia)RESUMO
The majority of past road safety studies focused on open road segments while only a few focused on tunnels. Moreover, the past tunnel studies produced some inconsistent results about the safety effects of the traffic patterns, the tunnel design, and the pavement conditions. The effects of these conditions therefore remain unknown, especially for freeway tunnels in China. The study presented in this paper investigated the safety effects of these various factors utilizing a four-year period (2009-2012) of data as well as three models: 1) a random effects negative binomial model (RENB), 2) an uncorrelated random parameters negative binomial model (URPNB), and 3) a correlated random parameters negative binomial model (CRPNB). Of these three, the results showed that the CRPNB model provided better goodness-of-fit and offered more insights into the factors that contribute to tunnel safety. The CRPNB was not only able to allocate the part of the otherwise unobserved heterogeneity to the individual model parameters but also was able to estimate the cross-correlations between these parameters. Furthermore, the study results showed that traffic volume, tunnel length, proportion of heavy trucks, curvature, and pavement rutting were associated with higher frequencies of traffic crashes, while the distance to the tunnel wall, distance to the adjacent tunnel, distress ratio, International Roughness Index (IRI), and friction coefficient were associated with lower crash frequencies. In addition, the effects of the heterogeneity of the proportion of heavy trucks, the curvature, the rutting depth, and the friction coefficient were identified and their inter-correlations were analyzed.
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Acidentes de Trânsito , Planejamento Ambiental , Segurança , Acidentes de Trânsito/estatística & dados numéricos , China , Humanos , Modelos Estatísticos , Veículos Automotores , RiscoRESUMO
Understanding defect effect on carrier dynamics is essential for both fundamental physics and potential applications of transition metal dichalcogenides (TMDs). Here, the phenomenon of oxygen impurities trapping photoexcited carriers has been studied with ultrafast pump-probe spectroscopy. Oxygen impurities are intentionally created in exfoliated multilayer MoSe2 with Ar+ plasma irradiation and air exposure. After plasma treatment, the signal of transient absorption first increases and then decreases, which is a signature of defect-capturing carriers. With larger density of oxygen defects, the trapping effect becomes more prominent. The trapping defect densities are estimated from the transient absorption signal, and its increasing trend in the longer-irradiated sample agrees with the results from X-ray photoelectron spectroscopy. First-principle calculations with density functional theory reveal that oxygen atoms occupying Mo vacancies create mid-gap defect states, which are responsible for carrier trapping. Our findings shed light on the important role of oxygen defects as carrier trappers in TMDs, and facilitate defect engineering in relevant materials and device applications.