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Soil respiration (Rs), a critical component of the global carbon (C) cycle, is sensitive to changes in nitrogen (N) deposition. However, the temporal dynamics of the effects of long-term (≥ five years) N addition and its cessation on Rs in forests remain uncertain. We conducted a continuous field experiment, which included three years of N cessation after seven years of N addition at different rates (0, 30, 60, and 90 kg N∙ha−1∙yr−1), in a subtropical Moso bamboo forest to explore the response of Rs and its components, determine the influence of biotic and abiotic factors to long-term N addition, and identify any legacy effects. We found a two-phase pattern of Rs, with a significant increase in the first two years across three N addition rates and a constant significant increase in the last five years across low and medium N addition; however, Rs did not change under high N addition. The nitrogen addition legacy effects significantly increased Rs and autotrophic respiration but reduced heterotrophic respiration, which could persist for at least three years. The mechanism underlying the temporal variation in Rs and its components was related to the increase in fine root biomass and changes in soil microbial biomass and bacteria to fungi ratio. These findings have advanced our understanding of soil CO2 dynamics in subtropical forests under N deposition. Moreover, they reveal that the legacy effects of long-term N addition should be incorporated into global C cycle modeling to reflect the persistent effects of N deposition on forest ecosystem C budgets.

ObjectivesThis study aimed to determine whether combined of pathogen detection strategies, including specimen acquisition, culture conditions, and molecular diagnostics, can improve treatment outcomes in patients with periprosthetic joint infections (PJI).MethodsThis retrospective study included suspected PJI cases from three sequential stages at our institution: Stage A (July 2012 to June 2015), Stage B (July 2015 to June 2018), and Stage C (July 2018 to June 2021). Cases were categorized into PJI and aseptic failure (AF) groups based on European Bone and Joint Infection Society (EBJIS) criteria. Utilization of pathogen diagnostic strategies, pathogen detection rates, targeted antibiotic prescription rates, and treatment outcomes were analyzed and compared across the three stages.ResultsA total of 165 PJI cases and 38 AF cases were included in this study. With the progressive implementation of the three optimization approaches across stages A, B and C, pathogen detection rates exhibited a gradual increase (χ2 = 8.282, P=0.016). Similarly, utilization of targeted antibiotic therapy increased stepwise from 57.1% in Stage A, to 82.3% in Stage B, and to 84% in Stage C (χ2 = 9.515, P=0.009). The 2-year infection control rate exceeded 90% in both stages B and C, surpassing stage A (71.4%) (χ2 = 8.317, P=0.011). Combined application of all three optimized protocols yielded the highest sensitivity of 91.21% for pathogen detection, while retaining higher specificity of 92.11%.ConclusionThe utilization of combined pathogen diagnostic strategies in PJI can increase pathogen detection rates, improve targeted antibiotic prescription, reduce the occurrence of antibiotic complications, and achieve better treatment outcomes.

In order to control the occurrence of ginseng root rot caused by Fusarium solani (Mart.) Sacc., the antifungal compounds of the mushroom Suillus bovinus were investigated. And three new alkaloids (1–3), named bovinalkaloid A–C, along with one known analog (4), were isolated and identified by bioassay-guided isolation and spectroscopic analyses. Compound 1 strongly inhibited the mycelial growth and spore germination of F. solani with minimum inhibitory concentration of 2.08 mM. Increases in electrical conductivity, nucleic acid, and protein contents, and decreases in lipid content showed that the membrane permeability and integrity were damaged by compound 1. Compound 1 also increased the contents of malondialdehyde and hydrogen peroxide and the activities of antioxidant enzymes, indicating that lipid peroxidation had taken place in F. solani. Compound 1 may serve as a natural alternative to synthetic fungicides for the control of ginseng root rot.

Edible mushrooms are an important source of nutraceuticals and for the discovery of bioactive metabolites as pharmaceuticals. In this work, six new polyphenolic metabolites suillusol A-D (1–4), suillusinoic acid (5), ethyl suillusinoate (6), were isolated from the Suillus granulatus. The structures of new compounds were elucidated using high-resolution electrospray ionization mass spectroscopy, nuclear magnetic resonance data, and single-crystal X-ray diffraction analysis. As far as we know, compound 1 represents an unprecedented type of natural product and compound 3 represents a new type of polyphenol fungal pigment, which may be biosynthetically related to thelephoric acid. The cytotoxicity against HepG2 cells of the new compounds were also evaluated. Compound 2 demonstrate significant inhibitory activity against HepG2 cells with IC50 values of 10.85 μM, surpassing that of positive control cisplatin. Moreover, compound 1 and 3 also exhibited moderate cytotoxic activity with their IC50 values measured at 35.60 and 32.62 μM, respectively. Our results indicate that S. granulatus is a rich source of chemical constituents that may provide new lead compounds for the development of anticancer agents.

When cutting roof and pressure relief, the impact of blasting is especially obvious on the integrity of the roof of a large-section soft-rock roadway. The reasonable parameters of blasting roof cutting were studied through using Xiaohezui coal mine -12110 roadway as the engineering background. The LS-Dyna simulation results show that: Interval blasting is beneficial to the expansion of interhole cracks and the damage to the perimeter of the hole is smaller than that of adjacent blasting, the lower the charge uncoupling factor, the larger the perimeter of the hole fragmentation zone. The mechanical model of the large-section soft-rock roadway after retrieval was established, the support resistance equation of the roadway side support and the gangue in the extraction area was derived, and the minimum support force required for the roadway side support was solved. According to the site situation, the roadway support scheme for different areas was proposed, and after continuous delamination monitoring of the roof plate, it was found that the amount of roof-plate delamination was finally stabilized within 180 mm after the working face was advanced, and the effect of leaving the roadway was good.

A systematic study of the movement of PAHs (Polycyclic aromatic hydrocarbons) and their derivatives through air, soil, and water is key to understanding the exchange and transport mechanisms of these pollutants in the environment and for ultimately improving environmental quality. PAHs and their derivatives, such as nitrated PAHs (NPAHs), oxygenated PAHs (OPAHs), brominated PAHs (BrPAHs) and chlorinated PAHs (ClPAHs), were analyzed in air, bulk deposition, soil, and water samples collected from urban, rural, field, and background sites on the eastern coast of China. The goal was to investigate and discuss their spatiotemporal variations, exchange fluxes, and transport potential. The concentrations of PAHs and their derivatives in the air and bulk deposition displayed distinct seasonal patterns, with higher concentrations observed during the winter and spring and lower concentrations during the summer and autumn. NPAHs exhibited the opposite trend. Significant urban-rural gradients were observed for most of the PAHs and their derivatives. According to the air-soil fugacity calculations, 2–3 ring PAHs, BrPAHs, and ClPAHs were found to volatilize from the soil into the air, while 4–7 ring PAHs, OPAHs, and NPAHs deposited from the air into the soil. The air-water fugacity of the PAHs and their derivatives indicated that surface water was an important source for the ambient atmosphere in Qingdao. The characteristic travel distances (CTDs) and persistence (Pov) for atmospheric transport were much lower than that for the water samples, which may be due to the longer half-lives of PAHs and their derivatives in water. NPAHs and ClPAHs with long transport distances and strong persistence in water could lead to a significant impact on marine pollution.

Molybdenum (Mo) is considered as a promising plasma-facing material, which is expected to be used in the manufacture of critical components for the neutral beam injection (NBI) inductively coupled plasma (ICP) source. Hydrogen isotope retention and bubble formation are regarded as the unavoidable issues that degrade the metal properties in the ion source. In this work, the evolution of hydrogen bubbles in Mo pre-irradiated by 35 eV hydrogen ion energy during different annealing processes is studied through conductive atomic force microscopy (CAFM) observation. Meanwhile, the corresponding numerical simulation is applied to analyze the mechanisms of hydrogen bubble growth. It is found that the average size and density of hydrogen bubbles are enhanced with the increase of hydrogen ion fluence at 400 K in experiments and simulations. In the subsequent annealing process, it is demonstrated that annealing temperature has a certain effect on bubble growth and evolution. No obvious changes in bubbles are observed at the annealing temperature below 573 K. The average radius of hydrogen bubbles is increased by ∼1.0–2.5 nm in Mo annealed at 673–873 K. The bubble size increases with the rise of annealing temperature, indicating that the thermal annealing promotes the growth of bubbles. When the temperature rises above 873 K, the change in bubble size is not obvious. The simulation results indicate that temperature-induced changes in the internal pressure of hydrogen bubbles leads to the growth of bubbles, but this mechanism is not significant under high annealing temperatures due to the release of hydrogen from the surface.

Abstract Background It is still not clear whether the effects of N deposition on soil greenhouse gas (GHG) emissions are influenced by plantation management schemes. A field experiment was conducted to investigate the effects of conventional management (CM) versus intensive management (IM), in combination with simulated N deposition levels of control (ambient N deposition), 30 kg N·ha− 1·year− 1 (N30, ambient + 30 kg N·ha− 1·year− 1), 60 kg N·ha− 1·year− 1 (N60, ambient + 60 kg N·ha− 1·year− 1), or 90 kg N·ha− 1·year− 1 (N90, ambient + 90 kg N·ha− 1·year− 1) on soil CO2, CH4, and N2O fluxes. For this, 24 plots were set up in a Moso bamboo (Phyllostachys edulis) plantation from January 2013 to December 2015. Gas samples were collected monthly from January 2015 to December 2015. Results Compared with CM, IM significantly increased soil CO2 emissions and their temperature sensitivity (Q 10) but had no significant effects on soil CH4 uptake or N2O emissions. In the CM plots, N30 and N60 significantly increased soil CO2 emissions, while N60 and N90 significantly increased soil N2O emissions. In the IM plots, N30 and N60 significantly increased soil CO2 and N2O emissions, while N60 and N90 significantly decreased soil CH4 uptake. Overall, in both CM and IM plots, N30 and N60 significantly increased global warming potentials, whereas N90 did not significantly affect global warming potential. However, N addition significantly decreased the Q 10 value of soil CO2 emissions under IM but not under CM. Soil microbial biomass carbon was significantly and positively correlated with soil CO2 and N2O emissions but significantly and negatively correlated with soil CH4 uptake. Conclusion Our results indicate that management scheme effects should be considered when assessing the effect of atmospheric N deposition on GHG emissions in bamboo plantations.

Background: There have been marked advances in devices such as Amplatzer Duct Occluder II (ADO-II) or vascular plug through 5Fr delivery sheath for closure of patent ductus arteriosus (PDA) in the past five decades, making it possible for cardiologists to deliver occluders via different approaches. However, comparisons of these different approaches have not been reported. Therefore, the aim of this study was to summarize and compare the advantages of different approaches for PDA closure, and to guide clinical strategies.Methods: This retrospective study included all patients undergoing transcatheter closure of PDA from 2019 to 2020. Patients were matched by 1:1 propensity score matching (PSM). The retrograde femoral artery approach (FAA) and simple vein approach (SVA) groups were compared with the conventional arteriovenous approach (CAA).Results: The average age of the 476 patients was 21.05 ± 21.15 years. Their average weight was 38.23 ± 24.1 kg and average height was 130.14 ± 34.45 cm. The mean diameter of the PDA was 4.29 ± 2.25 mm. There were 127 men and 349 women, comprising 205 adults and 271 children. Among them, 197 patients underwent CAA, 223 underwent SVA, and 56 underwent retrograde FAA. The diameter in the FAA group was smaller than that in the other two groups, but was similar in adults and children. In the PSM comparison of CAA and SVA, 136 patients with CAA and 136 patients with SVA were recruited. Simple vein approach was associated with markedly reduced length of hospital stay, length of operation, and contrast medium usage as compared with CAA (all P < 0.05). In the PSM comparison of FAA and CAA, 30 patients with CAA and 30 patients with FAA were recruited. The operation duration was longer in the CAA than in the FAA group. There were no significant differences in postoperative complications among groups.Conclusion: Patent ductus arteriosus closure by using the SVA and FAA is safe and effective, and has certain advantages in some respects as compared with CAA.

Methane (CH4) is one of the three most important greenhouse gases. To date, observations of ecosystem-scale methane (CH4) fluxes in forests are currently lacking in the global CH4 budget. The environmental factors controlling CH4 flux dynamics remain poorly understood at the ecosystem scale. In this study, we used a state-of-the-art eddy covariance technique to continuously measure the CH4 flux from 2016 to 2018 in a subtropical forest of Zhejiang Province in China, quantify the annual CH4 budget and investigate its control factors. We found that the total annual CH4 budget was 1.15 ± 0.28~4.79 ± 0.49 g CH4 m−2 year−1 for 2017–2018. The daily CH4 flux reached an emission peak of 0.145 g m−2 d−1 during winter and an uptake peak of −0.142 g m−2 d−1 in summer. During the whole study period, the studied forest region acted as a CH4 source (78.65%) during winter and a sink (21.35%) in summer. Soil temperature had a negative relationship (p < 0.01; R2 = 0.344) with CH4 flux but had a positive relationship with soil moisture (p < 0.01; R2 = 0.348). Our results showed that soil temperature and moisture were the most important factors controlling the ecosystem-scale CH4 flux dynamics of subtropical forests in the Tianmu Mountain Nature Reserve in Zhejiang Province, China. Subtropical forest ecosystems in China acted as a net source of methane emissions from 2016 to 2018, providing positive feedback to global climate warming.

ObjectiveThe aims of this study were to identify the influencing factors such as gender, age, dose and combinations of other antiepileptic drugs (AEDs), especially in triple combinations on the pharmacokinetic of Lamotrigine (LTG) in epilepsy patients of Northwest Chinese Han population.MethodsData of the LTG concentration and clinical information were analyzed retrospectively from a therapeutic drug monitoring (TDM) database at the Clinical Pharmacy Laboratory of Xi'an Central Hospital between January 1, 2016 and January 1, 2018. The independent-sample t-test, one-way ANOVA analysis and Bonferroni and Tamhane T3 post-hoc test, the stepwise multivariate regression analysis were adopted by IBM SPSS, version 22.0.Results226 serum samples met the inclusion criteria and were evaluated. The mean LTG serum concentration was 5.48±3.83 μg/mL. There were no gender differences (P = 0.64), and there were no significant effects by age on LTG serum concentration after age stratification (3-14 years old, 14-45 years old, 45-59 years old) (P = 0.05). Multiple regression analysis showed that the daily LTG dose and co-administration of other AEDs significantly affected LTG serum concentrations. Combination with enzyme-inducer AEDs, the mean steady-state LTG concentration could be decreased by 30.73% compared with LTG monotherapy. Among enzyme-inducer AEDs, particularly strong inducer Carbamazepine (CBZ) could decrease the mean LTG concentration by 53.65%, but weak inducer AEDs such as Oxcarbazepine (OXC) and Topiramate (TPM) had no effect, Valproic acid (VPA) could increase the mean LTG concentration by 93.95%, and the inducer only partially compensated for the inhibitory effect of VPA in triple combination.ConclusionsThere were no significant gender and age effects, but the LTG daily dose and co-administration of other AEDs significantly affected LTG serum concentration. Combination with enzyme-inducer AEDs, especially CBZ could significantly decrease LTG serum concentrations, VPA could significantly increase LTG serum concentrations, and the inducer only partially compensated for the inhibitory effect of VPA in triple combination. In the clinical setting, these findings can help to estimate LTG concentrations and adjust dosage and evaluate adverse drug reactions.

Ecosystem-level effects of increasing atmospheric nitrogen (N) deposition on the phosphorus (P) cycle and P use strategy are poorly understood. Here, we conducted a seven year N-addition experiment to comprehensively evaluate the effects of N deposition on P limitation, cycling, and use strategy in a subtropical Moso bamboo forest. N addition significantly increased foliar litterfall by 4.7%–21.7% and subsequent P return to the soil by 49.0%–70.1%. It also increased soil acidity, acid phosphatase activity, and soil microbial biomass P, which substantially contributed to a significantly increased soil P availability and largely alleviated the P limitation. This resulted in a significant decrease in the foliar P-resorption efficiency and the abundance and colonization of arbuscular mycorrhizal fungi. Our results indicate that N deposition can reduce plant internal cycling while enhancing ecosystem-scale cycling of P in Moso bamboo forests. This suggests a shift in P use from a ‘conservative consumption’ strategy to a ‘resource spending’ strategy. Our findings shed new light on N deposition effects on P cycle processes and P use strategy at the ecosystem scale under increasing atmospheric N deposition.

An environmentally benign approach is put forward with the focus on directly liquefying and depolymerizing Cunninghamia lanceolata (Lamb.) Hook. (Chinese fir) sawdust into ethyl levulinate (EL) under supercritical ethanol (scEtOH) conditions by using phosphotungstic acid (PTA) as a catalyst. The effects of parameters such as catalyst dosage, temperature, and reaction time on alcoholysis yield were investigated. The experimental results show that the biomass alcoholysis yield reached 95.35% with 0.5 g PTA as a catalyst at 260 °C for 30 min. Alcoholysis yield and quantitative content of EL depended on the catalyst. The light bio-oil was primarily composed of phenols, aldehydes, ketones, and esters. A high quantitative content of EL up to 20.82% (AR, Relative abundance) was achieved, compared to 0.73% AR when PTA was not added. Hence, scEtOH with dissolved PTA may offer novel media for both chemical reactions and biomass conversion technology as a replacement for environmentally undesirable organic solvents.

Although the toxic effects of bee venom (BV) in humans are known, there are only a few systematic studies are available in literature. Here, we have evaluated the potential toxicity of BV from Apis mellifera L. (Hymenoptera: Apidae) by studying acute toxicity in mice receiving subcutaneous injections of high (120 mg/kg), medium (60 mg/kg) and low (8 mg/kg) doses of BV. General toxicity symptoms and histopathological changes were recorded for 14 days. The results indicated that highdose BV could be fatal. The mental state, appetite, and respiration of mice in the medium- and high-dose groups changed in varying degrees; higher doses led to more prominent symptoms (LD50, 119.7 mg/kg). BV in medium- and high-dose groups significantly inhibited weight gain in mice within 2 days, which did not significantly differ between the dose groups and control at the later stage. The hemolysis rate was significantly higher in the low-dose, while in the medium- and high-dose groups, the coagulation time significantly prolonged in male mice. Histopathological changes showed that medium- and high-dose groups exhibited toxicity to tested organs. Our study showed that BV exhibited strong toxicity at higher concentration and is relatively safe when the BV concentration is lower than 8 mg/kg. [ABSTRACT FROM AUTHOR]