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Understanding how nutrient addition affects the tree growth is critical for assessing forest ecosystem function and processes, especially in the context of increased nitrogen (N) and phosphorus (P) deposition. Subtropical forests are often considered N-rich and P-poor ecosystems, but few existing studies follow the traditional "P limitation" paradigm, possibly due to differences in nutrient requirements among trees of different size classes. We conducted a three-year fertilization experiment with four treatments (Control, N-treatment, P-treatment, and NP-treatment). We measured soil nutrient availability, leaf stoichiometry, and relative growth rate (RGR) of trees across three size classes (small, medium and large) in 64 plots. We found that N and NP-treatments increased the RGR of large trees. P-treatment increased the RGR of small trees. RGR was mainly affected by N addition, the total effect of P addition was only 10 % of that of N addition. The effect of nutrient addition on RGR was mainly regulated by leaf stoichiometry. This study reveals that nutrient limitation is size dependent, indicating that continuous unbalanced N and P deposition will inhibit the growth of small trees and increase the instability of subtropical forest stand structure, but may improve the carbon sink function of large trees., Competing Interests: Declaration of competing interest The author declare that they have no conflict of interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Severe pneumonitis (≥ grade 3 by Common Terminology Criteria for Adverse Events [CTCAE]) is a toxicity associated with concurrent chemoradiation therapy (CCRT), which is the standard first-line treatment for patients with limited-stage small cell lung cancer (LS-SCLC). We summarize and quantify the risk of pneumonitis in LS-SCLC patients receiving first-line CCRT. A systematic literature review (SLR) and meta-analysis were performed in accordance with Cochrane and PRISMA guidelines. Electronic databases were searched to identify relevant randomized controlled trials (RCTs), observational studies, and non-randomized trials between 2014 to July 16, 2020. The primary outcome was incidence of pneumonitis. Thirteen studies were included in the SLR and 1539 pooled patients from 10 studies were included in the base-case meta-analysis. The pooled incidence of ≥ grade 3 pneumonitis was 3.28% (95% confidence interval [CI]: 1.52%-5.04%) in RCTs, and 6.34% (95% CI: 3.64%-9.04%) in non-RCTs. The pooled incidence risk of grade 5 (fatal) pneumonitis was 0.29% (95% CI: 0.00%-0.62%) in RCTs and 0.88% (95% CI: 0.02%-1.74%) in non-RCT. Results from sensitivity analyses were consistent with the base-case analysis. The results from this analysis show that the incidence of ≥ grade 3 pneumonitis in patients with LS-SCLC was 3.28% to 6.34%. The incidence of pneumonitis was higher in studies conducted in non-RCTs compared to RCTs. These results can be used to understand the safety, with regard to pneumonitis, of novel therapeutic agents when administered with CCRT to treat patients with LS-SCLC. To summarize and quantify the risk of pneumonitis in LS-SCLC patients receiving first-line CCRT, a systematic literature review (SLR) and meta-analysis were performed in accordance with Cochrane and PRISMA guidelines., (Copyright © 2022. Published by Elsevier Inc.)

Elevational range shifts of mountain species in response to climate change have profound impact on mountain biodiversity. However, current evidence indicates great controversies in the direction and magnitude of elevational range shifts across species and regions. Here, using historical and recent occurrence records of 83 plant species in a subtropical mountain, Mt. Gongga (Sichuan, China), we evaluated changes in species elevation centroids and limits (upper and lower) along elevational gradients, and explored the determinants of elevational changes. We found that 63.9% of the species shifted their elevation centroids upward, while 22.9% shifted downward. The changes in centroid elevations and range size were more strongly correlated with changes in lower than upper limits of species elevational ranges. The magnitude of centroid elevation shifts was larger than predicted by climate warming and precipitation changes. Our results show complex changes in species elevational distributions and range sizes in Mt. Gongga, and that climate change, species traits and climate adaptation of species all influenced their elevational movement. As Mt. Gongga is one of the global biodiversity hotspots, and contains many threatened plant species, these findings provide support to future conservation planning., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Photolysis of nitrous acid (HONO) is one of the major sources for atmospheric hydroxyl radicals (OH), playing significant role in initiating tropospheric photochemical reactions for ozone (O 3 ) production. However, scarce field investigations were conducted to elucidate this effect. In this study, a field campaign was conducted at a suburban site in southwest China. The whole observation was classified into three periods based on O 3 levels and data coverage: the serious O 3 pollution period (Aug 13-18 as P1), the O 3 pollution period (Aug 22-28 as P2) and the clean period (Sep 3-12 as P3), with average O 3 peak values of 96 ppb, 82 ppb and 44 ppb, respectively. There was no significant difference of the levels of O 3 precursors (VOCs and NOx) between P1 and P2, and thus the evident elevation of OH peak values in P1 was suspected to be the most possible explanation for the higher O 3 peak values. Considering the larger contribution of HONO photolysis to HO X primary production than photolysis of HCHO, O 3 and ozonolysis of Alkenes, sensitivity tests of HONO reduction on O 3 production rate in P1 are conducted by a 0-dimension model. Reduced HONO concentration effectively slows the O 3 production in the morning, and such effect correlates with the calculated production rate of OH radicals from HONO photolysis. Higher HONO level supplying for OH radical initiation in the early morning might be the main reason for the higher O 3 peak values in P1, which explained the correlation (R 2  = 0.51) between average O 3 value during daytime (10:00-19:00 LT) and average HONO value during early morning (00:00-05:00 LT). For nighttime accumulation, a suitable range of relative humidity that favored NO 2 conversion within P1 was assumed to be the reason for the higher HONO concentration in the following early morning which promoted O 3 peak values., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Passivation of anode is a main challenge in the electrochemical synthesis of ferrate(VI) (Fe VI O 4 2- , Fe(VI)). A series of electrochemical approaches were employed including polarization curve, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS) to analyze the physicochemical processes involved in electrochemical synthesis of Fe(VI) using sponge iron and cast iron anodes. The results demonstrate that the sponge iron anode achieved higher yield of Fe(VI) compared to grey cast iron anode. The optimum condition to generate Fe(VI) using sponge iron was 35-50°C and 30mA/cm 2 . Significantly, the sponge iron anode could generate Fe(VI) for a long duration (>10h) under these conditions; possibly suitable for large scale synthesis of Fe(VI). The prepared Fe(VI) solution was used to treat antibiotic (sulfamethoxazole (SMX)) and pesticide (atrazine (ATZ)) in water. At a molar ratio of Fe(VI) to SMX as 20:1 in the pH range from 5.0 to 9.0, almost complete oxidative transformation of SMX could be obtained. Comparatively, oxidative transformation of ATZ was incomplete (∼70%) even when [Fe(VI)]:[ATZ]=87 at pH 5.0-9.0. Fluorescence spectra and cytotoxicity studies suggest that the oxidative transformation products of both SMX and ATZ possess lower toxicity than the parent antibiotic and pesticide, respectively., (Copyright © 2017. Published by Elsevier B.V.)

To determine whether evidence indicates that short-term exposure to ambient concentrations of ozone in the United States can affect asthma severity, we systematically reviewed published controlled human exposure, epidemiology, and animal toxicity studies. The strongest evidence for a potential causal relationship came from epidemiology studies reporting increased emergency department visits and hospital admissions for asthma following elevated ambient ozone concentrations. However, while controlled exposure studies reported lung function decrements and increased asthma symptoms following high ozone exposures 160-400 parts per billion [ppb]), epidemiology studies evaluating similar outcomes reported less consistent results. Animal studies showed changes in pulmonary function at high ozone concentrations (> 500ppb), although there is substantial uncertainty regarding the relevance of these animal models to human asthma. Taken together, the weight of evidence indicates that there is at least an equal likelihood that either explanation is true, i.e., the strength of the evidence for a causal relationship between short-term exposure to ambient ozone concentrations and asthma severity is "equipoise and above.", (Copyright © 2017 Elsevier Inc. All rights reserved.)

The current acceptable daily intake (ADI) for benzoic acid and its salts as food additives is 0-5 mg/kg body weight. This accounts for a total uncertainty factor (UF) of 100, which includes a default factor of 10 for interspecies differences. Based on pharmacokinetic data in rodents and humans, we derived a chemical-specific adjustment factor (CSAF) of 2 for the pharmacokinetic component of the interspecies UF. Additional analyses indicate that this CSAF is conservative and interspecies differences between rats and humans are likely closer to unity. Human clinical studies indicate that the pharmacokinetics of benzoic acid and its salts are similar in children and adults, and that there is a lack of adverse events in humans at doses comparable to the no observed adverse effect level (NOAEL) in rodents; this suggests that the pharmacokinetic UF for intraspecies variability, as well as the pharmacodynamic components of the UFs, may also be reduced, although we did not calculate to what degree. In conclusion, the total UF can be reduced to 50 (2 for interspecies differences in pharmacokinetics, 2.5 for interspecies differences in pharmacodynamics, and 10 for intraspecies variability), which would increase the ADI to 0-10 mg/kg body weight., (Copyright © 2017 Gradient. Published by Elsevier Inc. All rights reserved.)

Purpose: Despite evidence from experimental studies indicating that the herbicide, 2,4-dichlorophenoxyacetic acid (2,4-D), is not carcinogenic, several epidemiology studies have evaluated links between 2,4-D and cancer. Some suggest that 2,4-D is associated with non-Hodgkin's lymphoma (NHL), gastric cancer, and prostate cancer, but results have been inconsistent. We conducted meta-analyses to evaluate the weight of epidemiology evidence for these cancers., Methods: We identified articles from PubMed, Scopus, and TOXLINE databases and reference lists of review articles. We evaluated study quality and calculated summary risk estimates using random effects models. We conducted subgroup and sensitivity analyses when possible., Results: We identified nine NHL, three gastric cancer, and two prostate cancer studies for inclusion in our meta-analyses. We found that 2,4-D was not associated with NHL (relative risk [RR] = 0.97, 95% confidence interval [CI] = 0.77-1.22, I(2) = 28.8%, Pheterogeneity = .19), and this result was generally robust to subgroup and sensitivity analyses. 2,4-D was not associated with gastric (RR = 1.14, 95% CI = 0.62-2.10, I(2) = 54.9%, Pheterogeneity = .11) or prostate cancer (RR = 1.32, 95% CI = 0.37-4.69, I(2) 87.0%, Pheterogeneity = .01)., Conclusions: The epidemiology evidence does not support an association between 2,4-D and NHL, gastric cancer, or prostate cancer risk., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Multiple studies have investigated the relationship between asbestos-related pleural plaques (PPs) and lung function, with disparate and inconsistent results. Most use chest radiographs to identify PPs and simple spirometry to measure lung function. High-resolution CT (HRCT) scanning improves the accuracy of PP identification. Complete pulmonary function tests (PFTs), including spirometry, lung volumes, and diffusing capacity of the lung for carbon monoxide, provide a more definitive assessment of lung function. The goal of this study was to determine, using HRCT scanning and complete PFTs, the effect of PPs on lung function in Libby vermiculite miners., Methods: The results of HRCT scanning and complete PFTs performed between January 2000 and August 2012 were obtained from the medical records of 166 Libby vermiculite miners. Multivariate regression analyses with Tukey multivariate adjustment were used to assess statistical associations between the presence of PPs and lung function. Adjustments were made for age, BMI, smoking history, duration of employment, and years since last occupational asbestos exposure., Results: Nearly 90% of miners (n = 149) had evidence of PPs on HRCT scan. No significant differences in spirometry results, lung volumes, or diffusing capacity of the lung for carbon monoxide were found between miners with PPs alone and miners with normal HRCT scans. Miners with both interstitial fibrosis and the presence of PPs had a significantly decreased total lung capacity in comparison with miners with normal HRCT scans (P = .02). Age, cumulative smoking history, and BMI were significant covariates that contributed to abnormal lung function., Conclusions: Asbestos-related PPs alone have no significant effect on lung function in Libby vermiculite miners.

Adenylate cyclase (AC) toxin from Bordetella pertussis inserts into eukaryotic cells, producing intracellular cAMP, as well as hemolysis and cytotoxicity. Concentration dependence of hemolysis suggests oligomers as the functional unit and inactive deletion mutants permit partial restoration of intoxication and/or hemolysis, when added in pairs [M. Iwaki, A. Ullmann, P. Sebo, Mol. Microbiol. 17 (1995) 1015-1024], suggesting dimerization/oligomerization. Using affinity co-precipitation and fluorescence resonance energy transfer (FRET), we demonstrate specific self-association of AC toxin molecules in solution. Flag-tagged AC toxin mixed with biotinylated-AC toxin, followed by streptavidin beads, yields both forms of the toxin. FRET measurements of toxin, labeled with different fluorophores, demonstrate association in solution, requiring post-translational acylation, but not calcium. AC toxin mixed with DeltaR, an inactive mutant, results in enhancement of hemolysis over that with wild type alone, suggesting that oligomers are functional. Dimers and perhaps higher molecular mass forms of AC toxin occur in solution in a manner that is relevant to toxin action.