Electron Accumulation Induced by Electron Injection-Incomplete Discharge on NiFe LDH for Enhanced Oxygen Evolution Reaction.

Optimizing the local electronic structure of electrocatalysts can effectively lower the energy barrier of electrochemical reactions, thus enhancing the electrocatalytic activity. However, the intrinsic contribution of the electronic effect is still experimentally unclear. In this work, the electron injection-incomplete discharge approach to achieve the electron accumulation (EA) degree on the nickel-iron layered double hydroxide (NiFe LDH) is proposed, to reveal the intrinsic contribution of EA toward oxygen evolution reaction (OER). Such NiFe LDH with EA effect results in only 262 mV overpotential to reach 50 mA cm-2, which is 51 mV-lower compared with pristine NiFe LDH (313 mV), and reduced Tafel slope of 54.8 mV dec-1 than NiFe LDH (107.5 mV dec-1). Spectroscopy characterizations combined with theoretical calculations confirm that the EA near concomitant Vo can induce a narrower energy gap and lower thermodynamic barrier to enhance OER performance. This study clarifies the mechanism of the EA effect on OER activity, providing a direct electronic structure modulation guideline for effective electrocatalyst design.

Regulating Surface Defects to Achieve More Positive Light Soaking Effect in Perovskite Solar Cells.

The dynamic defect tolerance under light soaking is a crucial aspect of halide perovskites. However, the underlying physics of light soaking remains elusive and is subject to debate, exhibiting both positive and negative effects. In this investigation, we demonstrated that surface defects in perovskite films significantly impact the performance and stability of perovskite solar cells, closely correlated with light soaking behaviors. Removing the top surface layer through adhesive tape, the surface defect density noticeably decreases, leading to enhanced photoluminescence (PL) efficiency, prolonged carrier lifetime, and higher conductivity. Consequently, the power conversion efficiency (PCE) of solar cells improves from 17.70% to 20.5%. Furthermore, we confirmed a positive correlation between surface defects and the light soaking effect. Perovskite films with low surface defects surprisingly exhibit a 3-fold increase in PL intensity and an 85% increase in carrier lifetime under 500 s of continuous illumination at an intensity of 100 mW/cm2. Beyond the conventional strategy of suppressing defect trapping, we propose increasing the capability of dynamic defect tolerance as an effective strategy to enhance the optoelectronic properties and performance of perovskite solar cells.

In situ synthesis of tentacle-like NiC/Mo2C/NF nanorods array with excellent hydrogen evolution reaction at high current densities.

The problem limiting the use of hydrogen evolution reactions in industry is the inability of electrocatalysts to operate stably at high current densities, so the development of stable and efficient electrocatalysts is important for hydrogen production by water splitting. By designing a rational interface engineering not only can the problem of limited number of catalytic sites in the catalyst be solved, but also can facilitate electron transfer, thus enhancing the efficiency of water splitting. Here, we designed a two-stage chemical vapour deposition method to construct NiC/Mo2C nanorod arrays on nickel foam to enhance the electrocatalytic ability of the catalysts, which exhibited efficient HER catalytic activity due to their special tentacle-like nanorod structure and abundant heterogeneous junction surfaces, which brought about abundant active sites as well as promoted electron transfer capability. The resulting catalysts provide current densities of 10, 100 and 500 mA cm-2 with overpotentials of 31, 153 and 264 mV, and exhibit excellent stability at current densities of 10 mA cm-2 for 200 h. This discovery provides a new idea for the rational design of catalysts with special morphologies.

Effect of angiotensin II on irradiation exacerbated decompression sickness.

In some complicated situations, decompression sickness (DCS) combined with other injuries, such as irradiation, will seriously endanger life safety. However, it is still unclear whether irradiation will increase the incidence of DCS. This study was designed to investigate the damage effects of irradiation on decompression injury and the underlying mechanism. Sprague-Dawley rats were exposed to irradiation followed by hyperbaric decompressing and the mortality and decompression symptoms were observed. Lung tissue and bronchoalveolar lavage fluid were collected to detect the lung lesion, inflammation response, activity of the angiotensin system, oxidative stress, and relative signal pathway by multiple methods, including Q-PCR, western blot, and ELISA. As a result, pre-exposure to radiation significantly exacerbated disease outcomes and lung lesions of DCS. Mechanically, the up-regulation of angiotensin-converting enzyme expression and angiotensin II levels was responsible for the exacerbated DCS and lung lesions caused by predisposing irradiation exposure. Oxidative stress and PI3K/AKT signal pathway activation in pulmonary tissue were enhanced after irradiation plus decompression treatment. In conclusion, our results suggested that irradiation could exacerbate lung injury and the outcomes of DCS by activating the angiotensin system, which included eliciting oxidative stress and activation of the PI3K/AKT signal pathway.

Simulation of Land Use Pattern Based on Land Ecological Security: A Case Study of Guangzhou, China.

The process of rapid urbanization has intensified the conversion of different land use types, resulting in a substantial loss of ecological land and ecological security being threatened. In the context of China's vigorous advocacy of an ecological civilization, it is important to explore future land use patterns under ecological security constraints to promote sustainable development. The insufficient consideration of land ecological security in existing land use pattern simulation studies makes it difficult to effectively promote improvement in the ecological security level. Therefore, we developed a land use simulation framework that integrates land ecological security. Taking the sustainable development of land ecosystems as the core, the land ecological security index (LESI) and ecological zoning (EZ) were determined by the pressure-state-response (PSR) model and the catastrophe progression method (CPM). Natural development (ND) and ecological protection (EP) scenarios were then constructed taking the LESI and EZ into consideration. The CA-Markov model was used to simulate the land use pattern of Guangzhou for 2030 under the two scenarios. The results showed that (1) the study area was divided into four categories: ecological core zone, ecological buffer zone, ecological optimization zone, and urban development zone, with area shares of 37.53%, 31.14%, 16.96%, and 14.37%, respectively. (2) In both scenarios, the construction land around the towns showed outward expansion; compared with the ND scenario, the construction land in the EP scenario decreased by 369.10 km2, and the woodland, grassland, and farmland areas increased by 337.04, 20.80, and 10.51 km2, respectively, which significantly improved the ecological security level. (3) In the EP scenario, the construction land in the ecological core zone, ecological buffer zone, and ecological optimization zone decreased by 85.49, 114.78, and 178.81 km2, respectively, and no new construction land was added in the ecological core zone, making the land use pattern of the EP scenario more reasonable. The results of the study have confirmed that the land use pattern simulation framework integrating land ecological security can effectively predict land use patterns in different future scenarios. This study can provide suggestions and guidance for managers to use in formulating ecological protection policies and preparing territorial spatial planning.

Factors influencing abandoned farmland in hilly and mountainous areas, and the governance paths: A case study of Xingning City.

The current global pandemic has laid bare the importance of national food security to human survival. Many cultivated lands in the hilly, mountainous, and other marginalized areas have been abandoned on a large scale, resulting in a tremendous waste of agricultural resources, thereby threatening national food security. Here, we studied abandoned farmland in Xingning City, a mountainous area in northern Guangdong province. According to the "seeding-growing-harvesting" life cycle of cultivated plots, spatial superposition method and remote sensing change detection method were applied to identify abandoned arable land. Logistic regression model was used to reveal the influencing factors and occurrence mechanism of abandoned cropland at plot scale, and cluster analysis was used to discuss the classification and management strategies. Result showed that 16.83% of the cultivated land in the study area was severely abandoned, attributed to poor location, poor basic conditions, and fragmentation of the land. Further, the abandoned farmland was divided into output-driving type, cultivation condition-driving type, and plot-condition driving type. Based on these types, we proposed some countermeasures, such as adjusting agricultural structures, tamping agricultural infrastructures, strengthening land circulation, popularizing appropriate scale operations. These measures provide a reference to effectively curb abandoned farmland and improving the utilization efficiency of cultivated land, especially in recent years.

Construction of CoP/Co2P Coexisting Bifunctional Self-Supporting Electrocatalysts for High-Efficiency Oxygen Evolution and Hydrogen Evolution.

Development of a low cost, high activity, and stable nonprecious metal bifunctional catalyst for electrocatalytic water cracking is a hot topic and big challenge. In this paper, we prepared a nitrogen-doped carbon nanotube (NCNT)-enhanced three-dimensional self-supported electrocatalyst with CoP and Co2P coexistence by a two-step strategy of high-temperature carbonization and low-temperature phosphorylation. Furthermore, the induced three-dimensional carbon network skeleton facilitates rapid charge transfer. In addition, the active sites of the carbon foam (CF) are greatly increased by the construction of hollow structures. As a bifunctional electrocatalyst, CoP/Co2P/NCNT@CF exhibited excellent catalytic activity for both hydrogen evolution reaction and oxygen evolution reaction in alkaline media, requiring low overpotentials of 133 and 289 mV to obtain a current density of 10 mA cm-2, respectively. Additionally, the synthesized catalysts also exhibit good long-term stability, maintaining high catalytic activity after 20 h of continuous operation. We also confirmed the main driving force to improve the electron transfer between the heterostructures of Co and P by XPS spectra. The excellent electrocatalytic performance can be attributed to the close synergy between the highly active CoP/Co2P/NCNT and CF. This study provides a new strategy for the design of highly active bifunctional self-supporting electrocatalysts.

In-situ fabrication of NixSey/MoSe2 hollow rod array for enhanced catalysts for efficient hydrogen evolution reaction.

Alkaline water electrocatalysis is considered as one of the most reliable method to prepare the stable, inexpensive, and sustainable water splitting catalyst in large-scale. Recently, MoSe2 attracted great attention as a promising catalyst because of its high electrochemical activity and earth-abundant nature. In this paper, bionic NixSey/MoSe2 coralline-liked heterogeneous structures were successfully prepared on 3D nickel foam (NF) via a simple solvothermal process complemented by hydrothermal strategy with selenization and alkali treatment. Furthermore, to overcome the less active sites and poor electrical conductivity of MoSe2, we learned from the coral structure for the inspiration, and reported a novel hollow rod-like structure with increased active sites. Also, 1 T-2H MoSe2 improved the electrical conductivity of single phase MoSe2. We first confirmed the multi-phase of catalyst by XPS analysis with Mo 3d5/2 splited into two independent regions with the 2H and 1 T phase transition. The optimal ratio of NixSey/MoSe2/NF-5 exhibited excellent electrocatalytic activity towards HER in 1 M KOH, driving current densities of 10, 100 and 200 mA cm-2 at only 76, 165 and 194 mV with stability over 24 h. The work provides new ideas for the construction of transition metal selenides hollow rod array structures of efficient HER electrocatalysts.

N-Doped Graphenelike Nanostructures from p-Nitro Aniline-Based Foam: Formation, Structure, and Applications as a Nanofiller.

Production of snake foam based on p-nitro aniline (PNA) was considered fun in old-school chemistry laboratories. Herein, we report the fabrication of a new carbon nanomaterial from PNA-based foam. The resulting material, resembling graphene and consisting of nitrogen heteroatoms, is N-doped graphenelike nanostructures, and their morphology, structure, and stability are comprehensively examined using combined techniques including C-13 NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). An optimized route was also established for their large-scale production. Further experimental validation of them as a nanofiller in polymer [SEBS (20 wt %) and paraffin wax (80 wt %)]-based nanocomposites was carried out, and we found that the thermomechanical properties of the nanocomposites were synchronously improved, which was attributed to the enshrouding effect of the nanofiller to the polymer chains. Owing to their good thermomechanical property and low-cost feature, these new nanomaterials can be further explored as a promising candidate for applications in energy storage, catalysis, and CO2 capture.

Two novel human anti-CD25 antibodies with antitumor activity inversely related to their affinity and in vitro activity.

High tumor regulatory T (Treg) cell infiltration is associated with poor prognosis of many cancers. CD25 is highly expressed on tumor Treg cells and is a potential target for Treg deletion. Previously characterized anti-CD25 antibodies appear to have limited efficacy in tumor inhibition. Here we identified two human anti-CD25 antibodies, BA9 and BT942, which did not prevent the activation of IL-2R signaling pathway by IL-2. BT942 had weaker binding and cytotoxic activity to human CD25-expressing cell lines than BA9. But both demonstrated significant tumor growth inhibition in early and late-stage animal cancer models. BT942 resulted in a higher expansion of CD8+ T cells and CD4+ T cells in tumor microenvironment in mouse MC38 model compared to BA9. BT942 also demonstrated significant higher tumor growth inhibition and higher expansion of CD8+ T cells and CD4+ T cells in combination with an anti-PD1 antibody. Pharmacokinetic study of BT942 in cynomolgus monkeys demonstrated a half-life of 206.97 ± 19.03 h. Structural analysis by cryo-EM revealed that BT942 recognizes an epitope on opposite side of the CD25-IL-2 binding site, consistent with no IL-2 signaling blockade in vitro. BT942 appears to be an excellent candidate for cancer immunotherapy.

Defect-Rich Heterogeneous MoS2/rGO/NiS Nanocomposite for Efficient pH-Universal Hydrogen Evolution.

Molybdenum disulfide (MoS2) has been universally demonstrated to be an effective electrocatalytic catalyst for hydrogen evolution reaction (HER). However, the low conductivity, few active sites and poor stability of MoS2-based electrocatalysts hinder its hydrogen evolution performance in a wide pH range. The introduction of other metal phases and carbon materials can create rich interfaces and defects to enhance the activity and stability of the catalyst. Herein, a new defect-rich heterogeneous ternary nanocomposite consisted of MoS2, NiS and reduced graphene oxide (rGO) are synthesized using ultrathin αNi(OH)2 nanowires as the nickel source. The MoS2/rGO/NiS-5 of optimal formulation in 0.5 M H2SO4, 1.0 M KOH and 1.0 M PBS only requires 152, 169 and 209 mV of overpotential to achieve a current density of 10 mA cm-2 (denoted as η10), respectively. The excellent HER performance of the MoS2/rGO/NiS-5 electrocatalyst can be ascribed to the synergistic effect of abundant heterogeneous interfaces in MoS2/rGO/NiS, expanded interlayer spacings, and the addition of high conductivity graphene oxide. The method reported here can provide a new idea for catalyst with Ni-Mo heterojunction, pH-universal and inexpensive hydrogen evolution reaction electrocatalyst.

Chemically activated core-shell structured IF-WS2@C nanoparticles enhance sugarcane-based carbon/epoxy nanocomposites.

Ternary composites have demonstrated better capability than binary composites in enhancing the mechanical properties of the modified epoxy resins and are, therefore, currently under intensive investigation. Herein, we report a novel ternary nanocomposite prepared by filling a binary BPF (bisphenol F epoxy resin)/SCPs (sugarcane-based carbon powders) matrix with C-coated inorganic fullerene-like tungsten disulfide (IF-WS2@C) nanoparticles, and the analysis of its interface synergetic effect using XPS/FTIR. This activated nano-carbon core-shell structure filler is considered an ideal nanofiller and shows the excellent mechanical performance of the ternary composites. XRD, IR, XPS, SEM, and TEM characterizations were applied in investigating this nanocomposite. The improvement of the thermal and mechanical properties demonstrated the enhancement effects of this nanofiller. The results show that the great improvement of the bending modulus of 39.4% increased with the addition of 0.5 wt% IF-WS2@C nanoparticles, while 34.1% enhancement of bending strength was obtained with the addition of 0.2 wt% IF-WS2@C nanoparticles. The hardness and thermal conductivity were also boosted up to 5.2% and 33.1% with 0.5 wt% addition, respectively. The incorporation of a chemically activated coating may provide a novel means for improving graphite crystallization, which could somehow expand the potential application of IF-WS2@C nanoparticles.

Study on the mechanism of tunable ferromagnetic composites with different rare earth ions.

Size-controlled Fe3O4 nanoparticles doped with rare earth (RE) ions (La3+, Ce3+, and Dy3+) varying from 15 nm to 30 nm were successful synthesized by a hydrothermal method for potential applications in the fields of biomedicine, environmental protection and magnetic memory devices. They possessed good dispersibility, adjustable particle size and nearly spherical shape. The particle grain size was uniformly distributed and showed a low degree of agglomeration in comparison with undoped Fe3O4 nanoparticles. The FTIR results showed that the RE elements partially replaced Fe2+, occupied the octahedral position, and enhanced the vibration of the Fe-O bond. The XPS study further revealed that the valence states of La, Ce, and Dy are both positive trivalent. The XPS Fe 2p valence band spectra observed a shift in the peak position toward higher binding energy after RE doping, confirming the existence of RE ions in the octahedral position. This paper explains the mechanism of rare earth doping with Fe3O4, and clarifies the influence of the doping of different RE ions on its magnetic properties. The detailed analysis of RE-doped ferrite materials can open a new perspective in designing biomedical and spintronics materials with tailored properties by choosing suitable cation substitution.

Computed Tomography-Guided Biopsy for Small (≤20 mm) Lung Nodules: A Meta-Analysis.

PURPOSE: This study was designed to evaluate the diagnostic accuracy of computed tomography (CT)-guided biopsy for small lung nodules (SLNs) (≤20 mm) and to assess related complication rates. METHODS: We reviewed the Pubmed, Embase, and Cochrane Library databases to identify all relevant studies published as of April 2020. Random effects modeling were then used to evaluate pooled data pertaining to technical success rates, diagnostic accuracy, pneumothorax rates, and rates of hemoptysis. The meta-analysis was conducted using Stata v12.0. RESULTS: In total, we identified 25 relevant studies for incorporation into this meta-analysis, incorporating 2922 total CT-guided lung biopsy. Pooled technical success rates, diagnostic accuracy, pneumothorax rates, and hemoptysis rates were 94% (95% confidential interval [CI], 0.91-0.98), 90% (95% CI, 0.88-0.93), 19% (95% CI:, 0.15-0.24), and 12% (95% CI, 0.08-0.15), respectively. We observed significant heterogeneity among these studies for all 4 of these parameters (I = 90.0%, 82.7%, 88.6%, and 88.4%, respectively). When we conducted a meta-regression analysis, we did not identify any variables that influenced diagnostic accuracy or technical success, pneumothorax, or hemoptysis rates. Publication bias risk analyses suggested that there was relatively little risk of publication bias pertaining to pneumothorax rates (P = 0.400) or hemoptysis rates (P = 0.377). In contrast, we detected a high risk of publication bias pertaining to reported technical success rates (P = 0.007) and diagnostic accuracy (P = 0.000). CONCLUSIONS: A CT-guided biopsy can be safely and effectively used to diagnose SLNs.

Preoperative neoadjuvant chemotherapy on surgical condition and oncogene expression in advanced gastric cancer.

OBJECTIVE: To evaluate the effect of preoperative neoadjuvant chemotherapy regimen of XELOX (capecitabine combined with oxaliplatin) on surgical condition and oncogene expression in advanced gastric cancer. METHODS: From January 2015 to July 2016, 124 patients with advanced gastric cancer who were admitted to our hospital were selected. Random number table method was used to divide them into an observation group and a control group, 62 each group. The observation group received two courses of neoadjuvant chemotherapy (XELOX) before operation, and the control group received surgery. The operation condition, expression of oncogenes in gastric cancer lesions, occurrence of adverse reactions and the long-term prognosis were compared between the two groups. RESULTS: The R0 resection rate of the observation group was significantly higher than that of the control group, and the difference was statistically significant (P<0.05). The operation time of the observation group was shorter than that of the control group, the amount of intraoperative bleeding and the amount of postoperative drainage of the observation group were less than that of the control group, and the differences were statistically significant (P<0.05). The mRNA expression of gastrokine 1, multiple tumor suppressor protein, Wilms tumor gene on the X chromosome (WTX gene) and gene of phosphate and tension homology deleted on chromosome ten (PTEN gene) in the observation group after treatment was significantly higher than that in the control group before treatment, and the increase amplitude of the observation group was more obvious than that of the control group (P<0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P>0.05). In terms of long-term prognosis, the disease-free survival time and average survival time of the observation group during the two-year follow-up period were significantly better than those of the control group, and the recurrence rate of the observation group was significantly lower than that of the control group; the differences were statistically significant (P<0.05). CONCLUSION: Preoperative XELOX for advanced gastric cancer patients can effectively increase the proportion of radical surgery, reduce the risk of surgery, and significantly regulate the expression of oncogene, thus improving the long-term prognosis of patients.

Acoustic waveguide with virtual soft boundary based on metamaterials.

The use of acoustic metamaterials with novel phenomena to design acoustic waveguides with special properties has obvious potential application value. Here, we propose a virtual soft boundary (VSB) model with high reflectivity and half cycle phase loss, which consists of an acoustic propagation layer and an acoustic metamaterial layer with tube arrays. Then the waveguide designed by the VSB is presented, and the numerical and experimental results show that it can separate acoustic waves at different frequencies without affecting the continuity and the flow of the medium in the space. The VSB waveguide can enrich the functions of acoustic waveguides and provide more application prospects.

CT findings and features of postoperative abdominal infection patients with pancreatic carcinoma.

OBJECTIVE: To investigate the values of Computed Tomography (CT) in diagnosing postoperative pancreatic surgeryabdominalinfection and its efficacy and to provide a reasonable method for the diagnosis of abdominal infection. METHODS: Seventy-two patients who were confirmed as resectablepancreatic carcinoma by physical examination, CT, positron emission tomography (PET)/CT, endoscopic retrograde cholangiopancreatography (ER-CP), endoscopic ultrasonography and mesenteric angiography and were admitted to the Binzhou People's Hospital, Shandong, China, from July 2013 to July 2015 were randomly selected. The plain CT images and clinical data of the patients were retrospectively analyzed. RESULTS: Among 72 patients, 32 patients were diagnosed as abdominal infection by CT, three patients were misdiagnosed (two cases of intestinal obstruction and one case of intraperitoneal abscess), and 2 patients were wrongly diagnosed as suppurative abdominal inflammation. As regards distribution of CT imaging positive performance, the number of patients with intestinal loop abscess accounted for 41.7%, subphrenic abscess for 16.7%, pelvic abscess for 33.3%, the existence of septation for 25%, and emphysema sign for 16.7%. As to the distribution of CT findings of intestinal obstruction, 46.1% of patients had dilatation of intestine, 30.8% for bowel wall thickening, 7.7% had abnormal enhancement, 11.1% had density abnormality, and 15.4% had mesenteric effusion. CT features of purulent peritonitis showed 57.1% of patients had peritoneal thickening, 42.9% had peritoneal effusion, 42.9% had free intraperitoneal air, 14.3% had intestinal walls edema, and 28.6% had mesenteric edema. CONCLUSION: The diagnosis of postoperative abdominal infection of patients with pancreatic carcinoma using CT is quick and efficient showing the pattern and distribution of collection and the gross reaction to the exciting infection.

Effects of error on dose of target region and organs at risk in treating nasopharynx cancer with intensity modulated radiation therapy.

OBJECTIVE: To measure setup error of head and neck neoplasm in radiotherapy and discuss over effects of error on physical dose acting on target region and organs at risk of nasopharynx cancer (NPC) patients treated with intensity modulated radiation therapy (IMRT). METHODS: A total of 152 patients who developed head and neck neoplasm and received IMRT were randomly selected. Through comparing digital portal image and digital reconstruction image, we measured setup error, calculated expanding margin from clinical target volume (CTV) to planning target volume (PTV) and analyzed whether there was rules between setup error and treatment time. Additionally, 20 cases of NPC were selected. Three-dimensional error was simulated in planning system. Dose distribution was recalculated and a series of dose parameters of target volume and OAR were analyzed. RESULTS: Setup error in left-right, head-feet and ventral-dorsal direction was (-0.62±1.46) mm, (-0.41±1.54) mm and (-0.31±1.67) mm respectively. Regarding limit value, the maximum and minimum value in left-right direction, head-feet direction and ventral-dorsal direction was 2.70 mm and -6.00 mm; 3.00 mm and -5.00 mm, 5.00 mm and -7.50 mm. Expanding margin from CTV to PTV was 2.26 mm, 1.88 mm and 1.97 mm in left-right direction, head-feet direction and ventral-dorsal direction. CONCLUSION: During IMRT, only when setup error is controlled below 3 mm can sharply reduce the damage caused by radiation to normal tissue; therefore, quality security and control of electronic portal imaging device need (EPID) to be improved.

Potential loss of phosphorus from a rice field in Taihu Lake basin.

Nonpoint-source pollution by phosphorus (P) poses a threat to waters in the Taihu Lake basin in China. The potential transfer of P in rice (Oryza sativa L.) fields through surface drainage and subsurface flow was investigated under simulated conventional irrigation-drainage management. Surface drainage events were conducted to avoid overflow across the plots after heavy rainfall and for rice harvest, at which time P losses were also investigated. This study was conducted in 2001 in a long-term rice field experiment. The experimental plots were treated with 0, 26, or 52 kg P ha(-1) as superphosphate or 26 kg P ha(-1) with equal parts of P supplied as superphosphate and pig manure. Phosphorus concentrations and loads in field floodwater on plots receiving P rapidly declined in a nonlinear manner before the first drainage, three weeks after fertilizer application. The combined application of fertilizer and manure P resulted in higher P transfer potential in field floodwater than with fertilizer P alone one week after P application. Phosphorus concentrations in interflow water sampled by Teflon suction cups inserted at a depth of 150 to 200 mm gradually increased within two weeks after P application, then declined. The concentration of P in interflow water was related to soil P buildup from long-term P application, as well as recently applied P. The 26 kg P ha(-1) treatment (the conventional P rate in this region) resulted in a loss of 0.74 kg total phosphorus (TP) ha(-1) and a drainage-weighted average concentration of 0.25 mg TP L(-1) from the three surface drainage events. Results indicate that avoiding overflow drainage after P input and extending the time between P application and drainage may reduce P losses from rice paddies.