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Gravity‐drainage‐assisted steam flooding is a new technology to improve the recovery factor after deep penetration in deep super‐heavy oil reservoirs. This study is based on a model of the 60‐H25 test well group in Block 59 in Liaohe Oilfield, China. The numerical model uses the C programming language to analyze the influence of change in the bottom water height on the drainage effect and provides a theoretical basis for physical model experiments and field production. The physical model experiment uses similar principles to describe the production characteristics at different stages in a short cycle. We combine the numerical model and the physical model experiment to analyze the production rule of the Wa59 block over a long time period. The results show that the physical model experiment and the actual production of the block reflect the productivity change law of the well group, the degree of production, and the productivity relationship of the well group over short cycles and long periods, respectively. The comparison showed that the actual production was consistent with the production model of the physical model test, and the drainage effect was verified. The study of gravity‐drainage‐assisted steam flooding provides a reliable basis for the next stage of oilfield production. [ABSTRACT FROM AUTHOR]

The summer monsoon shows a fundamental influence on the pelagic ecosystem of the South China Sea. Zooplankton are a major link for energy transfer between primary producers and upper trophic levels. Therefore, evaluating the energy transfer efficiency (ETE) of zooplankton is crucial to understand the function of pelagic ecosystem under the influence of monsoon. In this study, field surveys were conducted during May (intermonsoon) and August 2021 (summer monsoon) focusing on the variation of zooplankton size and trophic structures across the shelf and slope. The result showed that the summer monsoon reinforced the gradient of abundance, biovolume, and biomass from slope to shelf, and greatly intensified the role of environmental factors in driving spatial variation in most taxa. Both the results of size and trophic structures indicated that the ETE of zooplankton decreased from slope to shelf. The size structure also indicated that the ETE of zooplankton significantly increased under the influence of summer monsoon. These results were consistent with previous studies by different methods, suggesting that these approaches of size and trophic structures had important potential value in assessing changes in the function of marine pelagic ecosystem, especially when compared with sufficient historical data or reanalyzing historical samples. [Display omitted] • The effect of summer monsoon on ETE of zooplankton community was revealed. • The ETE of zooplankton significantly decreased from the slope to the shelf. • The ETE of zooplankton significantly increased during summer monsoon. • Size and trophic structure approaches can assess the function of pelagic ecosystem. [ABSTRACT FROM AUTHOR]

Cetacean falls provide a large amount of organic matter to the deep ocean, an otherwise oligotrophic environment. These events are now believed to maintain endemic species and offer intermediate habitats for species in other deep-sea ecosystems. Only about 70 modern whale falls have been reported in the world's oceans to date. We discovered the first known dolphin fall in the South China Sea in March 2020, on the middle slope of the Zhongnan seamount. We set up a camera at the site to observe animals visiting the dolphin carcass for 30 consecutive days from March 29 to April 28, 2020 and made four additional HOV dives to the dolphin carcass. In total, we observed 14 visible megafauna species visiting this dolphin fall, including six fish species, five crustacean species, two echinoderm species, and one mollusk species, of which most were scavengers or predators. This was the first record of many of these taxa in the deep South China Sea. Furthermore, two bone-eating worms were found in a piece of the dolphin bone. The worms are identified as new species in the genus Osedax based on DNA analysis. The findings of this work suggest that cetacean falls occur frequently in the South China Sea and help to fill a knowledge gap regarding the biodiversity of cetacean falls in the West Pacific. • A 1.8-m dolphin fall was found in the South China Sea for the first time. • We observed 14 visible megafauna species visiting this dolphin fall. • Two bone-eating worms were found in a piece of the dolphin bone. [ABSTRACT FROM AUTHOR]

Background: Delirium is a common postoperative complication after cardiac surgery. The relationship between delirium and cardiac function has not been fully elucidated. Aims: The aim of this study was to identify the association between preoperative cardiac function and delirium among patients after cardiac surgery. Methods: We prospectively recruited 635 cardiac surgery patients with a planned cardiac intensive care unit admission. Postoperative delirium was diagnosed using the confusion assessment method for the intensive care unit. Preoperative cardiac function was assessed using N-terminal prohormone of brain natriuretic peptide (NT-proBNP), New York Heart Association functional classification and left ventricular ejection fraction. Results: Delirium developed in 73 patients (11.5%) during intensive care unit stay. NT-proBNP level (odds ratio (OR) 1.24, 95% confidence interval (CI) 1.01–1.52) and New York Heart Association functional classification (OR 2.34, 95% CI 1.27–4.31) were both independently associated with the occurrence of delirium after adjusting for various confounders. The OR of delirium increased with increasing NT-proBNP levels after the turning point of 7.8 (log-transformed pg/ml). The adjusted regression coefficients were 1.19 (95% CI 0.95–1.49, P =0.134) for NT-proBNP less than 7.8 (log-transformed pg/ml) and 2.78 (95% CI 1.09–7.12, P =0.033) for NT-proBNP greater than 7.8 (log-transformed pg/ml). No association was found between left ventricular ejection fraction and postoperative delirium. Conclusion: Preoperative cardiac function parameters including NT-proBNP and New York Heart Association functional classification can predict the incidence of delirium following cardiac surgery. We suggest incorporating an early determination of preoperative cardiac function as a readily available risk assessment for delirium prior to cardiac surgery. [ABSTRACT FROM AUTHOR]

Background: Mild preoperative renal insufficiency is not rare in patients receiving isolated off-pump coronary artery bypass grafting surgery (OPCAB) surgery. However, there is less study aimed to evaluate the impact of mild preoperative renal insufficiency on in-hospital and follow-up outcomes after isolated OPCAB surgery. This single-centre, retrospective propensity score matching study aimed to evaluate the impact of mild preoperative renal insufficiency on in-hospital and long-term outcomes after first isolated OPCAB surgery.Methods: After propensity score matching, 1236 patients with preoperative estimated glomerular filtration rate (eGFR) of more than 60 ml/min/1.73 m(2) undergoing first isolated OPCAB surgery from January 2007 to December 2011 were entered into this study and were divided to normal group (eGFR ≥ 90 ml/min/1.73 m(2), n = 618) and mild group (eGFR of 60-89 ml/min/1.73 m(2), n = 618). The in-hospital and long-term outcomes were investigated and retrospectively analyzed.Results: The 2 propensity score-matched groups had similar baseline and procedural characteristics except the baseline eGFR. Thirty-five patients died during the same hospitalization or within 30 days of operation, with a surgical mortality of 2.8 %. Sixty-seven patients died during follow-up, with a long-term survival of 94.1 %. Univariate factor analysis showed that the 2 propensity score-matched groups have similar rates among in-hospital outcomes. Kaplan-Meier curves displayed a similar in-hospital survival between the 2 groups (χ(2) = 0.728, p = 0.393), while a better long-term survival in patients with normal preoperative renal function compared with mild preoperative renal insufficiency (χ(2) = 4.722, p = 0.030). After Cox proportional model was used, the hazard ratio for long-term mortality in patients with mild preoperative renal insufficiency compared with normal preoperative renal function was 1.72 (95 % CI 1.06-2.83, p = 0.032).Conclusions: Mild preoperative renal insufficiency compared with normal preoperative renal function reduced long-term survival, without evidence of worse in-hospital outcomes. [ABSTRACT FROM AUTHOR]

• Mismatch between phytoplankton and zooplankton was often observed in East China Sea. • Four hypotheses were tested to explain that mismatch in the present study. • Size diversity (SD) of zooplankton was the most important determinant of Z/P. • Seasonal change of determinants was also found. • It highlighted the SD approach in evaluation of carrying capacity for fish. The East China Sea (ECS) is the most important fishing ground in China. Field observations have always found no positive correlation between phytoplankton stocks and zooplankton biomass in the ESC. It has been suggested that under eutrophic conditions, the phytoplankton biomass is too high to limit mesozooplankton growth and lower the energy transfer efficiency from phytoplankton to mesozooplankton. However, this hypothesis does not explain the higher zooplankton biomass supported by lower chlorophyll a in offshore waters. This situation can be referred to as a "mismatch between phytoplankton and mesozooplankton" or "variation of Z/P". In this study, we used field data covering four seasons to test four hypotheses that (a) flatter slope of normalized biomass size spectrum (NBSS) of mesozooplankton enhances the Z/P; (b) higher mesozooplankton size diversity enhances the Z/P; (c) stronger predatory pressure from zooplanktivorous fish decreases the Z/P; and (d) larger-sized primary producers enhance the Z/P. The results of our study confirm that the size diversity of zooplankton was the most important determinant of spatial variation of Z/P in the ECS in each season except winter. The NBSS slope of zooplankton was also an important factor, but only significant in summer. Other potential mechanisms, including predation pressure from zooplanktivorous fish and larger-sized primary producers, were not determinants. This seasonal change was possibly due to seasonal variations of zooplankton community structure and functional structure in ECS, especially the large-sized and omnivorous Calanus sinicus transported by the stronger ECS Coastal Current during the winter. Our findings highlight the importance of a size diversity approach in the evaluation of the carrying capacity for fish in coastal ecosystems with conspicuous temporal and spatial variations. [ABSTRACT FROM AUTHOR]