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With the intensification of global change, the overall functions and structures of ecosystems in sub-humid to arid transition regions have changed to varying degrees. The Loess Plateau, as a typical case of such regions, plays a great role in the study of net primary productivity (NPP) for estimating the sustainability of the Earth's carrying capacity in terrestrial ecosystem process monitoring. In the research on contrasting response mechanisms and ecological stress of NPP, the main innovations of this study are as follows. On the basis of the indicator system constructed from satellite imagery and meteorological data, we introduced deep multiple regressive models to reveal the relationship between NPP and the identified driving factors and then creatively proposed ecological stress (ES) evaluation models from the perspective of vegetation productivity. The findings are as follows: 1) From 2000 to 2019, the changes in driving factors presented a clear regional character, and the annual NPP maintained a fluctuating increasing trend (with a value of 4.57 g-m2-a-1). From the perspective of spatial distribution, the growth rate of NPP gradually increased from arid to sub-humid regions. 2) The effects of different driving factors on NPP changes and specific NPPs varied greatly across different regions. Arid and semi-arid regions were mainly controlled by precipitation (20.49%), temperature (15.21%), and other related factors, whereas sub-humid regions were mainly controlled by solar radiation, such as net surface solar radiation (NSSR) (8.71%) and surface effective radiation (SER) (7.93%). The main driving factors of NPP change varied under different soil conditions. 3) The spatio-temporal patterns of NPP approximated those of ES, but the effects of the latter significantly differed across ecological functional regions and land uses. This research on the Loess Plateau can serve as a valuable reference for future research on realizing ecosystem restoration and protection in sub-humid to arid transition regions. [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]

• 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]

Background: Abiotrophia (ABI) and Granulicatella (GRA) are rare causative pathogens in infective endocarditis (IE). This study aims to describe the epidemiology, clinical characteristics, and outcome of ABI/GRA-IE. The main features of ABI/GRA-IE were compared with Viridans group streptococci (VGS) IE., Methods: From January 2015 to December 2023, a total of 1531 definite IE in Zhongshan Hospital, Fudan University, Shanghai, China were retrospectively enrolled in this study. Clinical and laboratory data were collected., Results: Forty-five ABI/GRA-IE cases were identified, representing 2.9% of all IE cases in Zhongshan Hospital between 2015 and 2023, compared to 20.1% of VGS-IE. ABI and GRA IE shared similar clinical characteristics. Congenital valvulopathy was reported in 21 (46.7%) ABI/GRA-IE and 85 (28.8%) VGS-IE (P = 0.025). Pulmonary valve was more frequently affected in ABI/GRA-IE (6 [13.3%]) than VGS-IE (7 [2.4%]) (P = 0.002). Congestive heart failure was observed in 30 (66.7%) ABI/GRA-IE and 103 (34.9%) VGS-IE (P < 0.001). Systemic embolization excluding central nervous system (CNS) occurred in 13 (28.9%) ABI/GRA-IE and 39 (13.2%) VGS-IE (P = 0.012). In-hospital mortality was reported as 4.4% in ABI/GRA-IE and 3.7% in VGS-IE (P = 0.854)., Conclusion: GRA/ABI-IE was approximately one-seventh as prevalent as VGS-IE. Congestive heart failure and systemic embolization (excluding CNS) were more frequent in GRA/ABI-IE compared to VGS-IE. Mortality of ABI/GRA-IE in this study was comparable to that of VGS-IE and lower than previously reported results., (© 2024. The Author(s).)

Background: Thoracic aortic aneurysm (TAA) is the permanent dilation of the thoracic aortic wall that predisposes patients to lethal events such as aortic dissection or rupture, for which effective medical therapy remains scarce. Human-relevant microphysiological models serve as a promising tool in drug screening and discovery., Methods: We developed a dynamic, rhythmically stretching, three-dimensional microphysiological model. Using patient-derived human aortic smooth muscle cells (HAoSMCs), we tested the biological features of the model and compared them with native aortic tissues. Drug testing was performed on the individualized TAA models, and the potentially effective drug was further tested using β-aminopropionitrile-treated mice and retrospective clinical data., Findings: The HAoSMCs on the model recapitulated the expressions of many TAA-related genes in tissue. Phenotypic switching and mitochondrial dysfunction, two disease hallmarks of TAA, were highlighted on the microphysiological model: the TAA-derived HAoSMCs exhibited lower alpha-smooth muscle actin expression, lower mitochondrial membrane potential, lower oxygen consumption rate and higher superoxide accumulation than control cells, while these differences were not evidently reflected in two-dimensional culture flasks. Model-based drug testing demonstrated that metformin partially recovered contractile phenotype and mitochondrial function in TAA patients' cells. Mouse experiment and clinical investigations also demonstrated better preserved aortic microstructure, higher nicotinamide adenine dinucleotide level and lower aortic diameter with metformin treatment., Interpretation: These findings support the application of this human-relevant microphysiological model in studying personalized disease characteristics and facilitating drug discovery for TAA. Metformin may regulate contractile phenotypes and metabolic dysfunctions in diseased HAoSMCs and limit aortic dilation., Funding: This work was supported by grants from National Key R&D Program of China (2018YFC1005002), National Natural Science Foundation of China (82070482, 81771971, 81772007, 51927805, and 21734003), the Science and Technology Commission of Shanghai Municipality (20ZR1411700, 18ZR1407000, 17JC1400200, and 20YF1406900), Shanghai Municipal Science and Technology Major Project (2017SHZDZX01), and Shanghai Municipal Education Commission (Innovation Program 2017-01-07-00-07-E00027). Y.S.Z. was not supported by any of these funds; instead, the Brigham Research Institute is acknowledged., Competing Interests: Declaration of interests None declared., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Aims: The incidence of acute aortic dissection (AAD) has been shown to have seasonal variation, but whether this variation can be explained by non-optimum ambient temperature and temperature change between neighbouring days (TCN) is not clear., Methods and Results: We performed a time-stratified case-crossover study in the Registry of Aortic Dissection in China covering 14 tertiary hospitals in 11 cities from 2009 to 2019. A total of 8182 cases of AAD were included. Weather data at residential address were matched from nearby monitoring stations. Conditional logistic regression model and distributed lag nonlinear model were used to estimate the associations of daily temperature and TCN with AAD, adjusting for possible confounders. We observed an increase of AAD risk with lower temperature cumulated over lag 0-1 day and this association became statistically significant when daily mean temperature was below 24°C. Relative to the referent temperature (28°C), the odds ratios (ORs) of AAD onset at extremely low (-10°C) and low (1°C) temperature cumulated over lag 0-1 day were 2.84 [95% confidence interval (CI): 1.69, 4.75] and 2.36 (95% CI: 1.61, 3.47), respectively. A negative TCN was associated with increased risk of AAD. The OR of AAD cumulated over lag 0-6 days was 2.66 (95% CI: 1.76, 4.02) comparing the extremely negative TCN (-7°C) to no temperature change. In contrast, a positive TCN was associated with reduced AAD risk., Conclusion: This study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased risk of AAD onset., Key Question: Incidence of acute aortic dissection (AAD) was reported to have seasonal trends, but it remains unclear whether non-optimum ambient temperature and temperature change between neighbouring days (TCN) is associated with AAD onset., Key Finding: Daily mean temperature lower than 24°C was significantly associated with increased risk of AAD at lag 0-1 day. A negative TCN (temperature drop) was associated with increased risk of AAD, whereas a positive TCN was associated with decreased risk., Take Home Message: This multi-centre, case-crossover study provides novel and robust evidence that low ambient temperature and temperature drop between neighbouring days were associated with increased AAD risk., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2021. For permissions, please email: journals.permissions@oup.com.)

Objectives: Acute kidney injury (AKI) is a common complication of cardiac surgery. This study aimed to explore the effects of hyperuricaemia, being overweight and hyperlipidaemia as risk factors for AKI in patients following cardiac surgery (cardiac surgery-associated acute kidney injury (CSA-AKI))., Design: Retrospective observational study., Setting: University teaching, grade-A tertiary hospital in Shanghai, China., Participants: Patients who underwent cardiac surgery from July 2015 to December 2015 in Zhongshan Hospital, Fudan University., Main Outcome Measures: We investigated the effect of hyperuricaemia, in combination with being overweight and hyperlipidaemia, on the risk of CSA-AKI., Results: A total of 1420 patients were enrolled. The AKI incidence in the highest uric acid group was 44.4%, while that in the lowest uric acid group was 28.5% (p<0.001). Patients in the higher uric acid quartiles were more likely to be overweight and hyperlipidaemic at the same time (p<0.001). Multivariate logistic regression analysis showed that hyperuricaemia was an independent risk factor for AKI (OR=1.237, 95% CI 1.095 to 1.885; p=0.009); being overweight or hyperlipidaemia alone was not an independent risk factor, but the combination of being overweight and hyperlipidaemia was (OR=1.544, 95% CI 1.059 to 2.252; p=0.024). In the final model, the OR value increased to 3.126 when hyperuricaemia was combined with being overweight and hyperlipidaemia, and the Hosmer-Lemeshow test showed that all three models fit well (p=0.433, 0.638 and 0.597, respectively)., Conclusions: The combination of being overweight and having hyperlipidaemia was an independent risk factor, but being overweight or having hyperlipidaemia alone was not. The combination of hyperuricaemia, being overweight and hyperlipidaemia further increased the risk of CSA-AKI., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Aim: Previous studies have provided evidence linking the DPEP1 gene to the risk of osteoarthritis (OA) in Europeans. In this study, we aimed to examine the relationship between DPEP1 gene and the susceptibility and clinical severity of OA in a Chinese Han population., Methods: This study comprised two independent samples. For the discovery stage, 1022 patients with knee OA and 1864 controls were recruited. Fourteen tag single nucleotide polymorphisms (SNPs) covering the DPEP1 gene were selected and genotyped. Associated SNPs in the discovery data set were subsequently genotyped in the replication data set consisting of 826 hip OA cases and 1662 controls. Both genotypic and allelic genetic associations were tested. The relationship of significant SNPs to the expression of DPEP1 and its neighboring genes was examined using the GTEx database., Results: A nonsynonymous SNP, rs1126464, was determined to be associated with the disease status of OA in both the discovery and replication stages (odds ratio [OR] 0.75, 95% confidence interval [95% CI] 0.68-0.82, P = 7.16 × 10 -11 ). This SNP was further characterized as being significantly related to a higher Kellgren-Lawrence grade in OA patients (OR 0.64, 95% CI 0.55-0.74, P = 2.53 × 10 -9 ). According to the GTEx data, SNP rs1126464 was significantly related to the gene expression of 15 genes in multiple types of human tissues., Conclusion: We reported a common DNA variant in the DPEP1 gene that contributes to the risk of OA, providing additional evidence that the DPEP1 gene plays a significant role in the pathological mechanisms of OA., (© 2021 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd.)

Objectives: In addition to the association between positive fluid balance (FB) and acute kidney injury (AKI) after cardiac surgery reported by former studies, this study examined the relationship between FB and progressive AKI., Design: A retrospective, observational study., Setting: University teaching, grade A tertiary hospital in Shanghai, China., Participants: Adult patients after cardiac surgery from July-December 2016., Interventions: Perioperative data relating to postoperative fluid intake and output were collected. AKI progression was defined as a worsening of AKI stage. FB was calculated as (fluid intake [L] - fluid output [L]/body weight [kg] × 100%)., Measurements and Main Results: The study comprised 1,522 patients. The incidences of AKI and progressive AKI were 33.1% (n = 504) and 18.1% (n = 91), respectively. There was an exponential increase between 24-hour FB and AKI occurrence, and an approximate "U"-shape association between 48-hour FB and AKI progression. Multivariate logistic regression showed that 24-hour FB ≥5% was an independent risk factor for AKI incidence (odds ratio [OR] 3.976; p < 0.001) and 48-hour FB <-5% or ≥3% was associated with an increase of AKI progression (FB <-5%, OR 7.078 [p = 0.031]; FB 3%-5%, OR 6.598 [p = 0.020]; FB ≥5%, OR 16.453 [p < 0.001])., Conclusions: An exponential increase was found between 24-hour FB and AKI occurrence and a "U"-shape association between 48-hour FB and AKI progression. Both excessively negative and positive accumulative 48-hour FB increased the risk of AKI progression, suggesting cautious monitoring and application of fluid load in clinical practice., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)