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Leaf hydraulic traits are considered the key determinants of gas exchange and therefore affect species distributions along environmental gradients, but the patterns of leaf hydraulic traits and their associations with gas exchange across altitudinal gradients remain largely unknown.Here, we measured leaf hydraulic traits, gas exchange, leaf anatomical traits and plant size traits in two dominant alpine shrubs (Caragana jubata and Salix gilashanica) across an altitudinal gradient from 3100 to 3700 m.The findings indicated that with increasing altitude, both shrub species exhibited an increase in leaf hydraulic safety (more negative KleafP50), a decrease in leaf hydraulic efficiency (Kleaf‐max) and an increase in intrinsic water use efficiency (WUEi), thus allowing them to adapt to higher altitude habitats. The more negative KleafP50 was associated with a greater ratio of major to minor vein density (VLAmaj/VLAmin), the lower Kleaf‐max was associated with a lower minor vein density (VLAmin) and greater increase in WUEi arose from the small decrease in the photosynthetic rate relative to the stomatal conductance. However, C. jubata was consistent with the 'hydraulic safety strategy' with a great decrease in KleafP50, a small decrease in Kleaf‐max and a small increase in WUEi along with decreasing plant height and leaf area with increasing altitude. Whereas S. gilashanica was consistent with the 'photosynthetic efficiency strategy' with a small decrease in KleafP50, a greater decrease in Kleaf‐max and a greater increase in WUEi along with an increasing plant height and unchanged leaf area with increasing altitude.Overall, these findings provide new insights to improve understanding how shift in leaf hydraulic traits and their associations with gas exchange and plant size allow plants to adapt to high‐altitude habitats. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Although the luminescent performance of organic–inorganic metal halides (OIMHs) have obtained significant advances, achieving intrinsic water‐stable OIMHs remain a substantial challenge due to the fragile ionic nature of hybrid the halide structure. To overcome these challenges, a structural design strategy is proposed that involves the use of highly hydrophobic cations as a protective layer to improve the water stability of OIMH. Herein, an aprotic trimethylsulfoxonium [TMSO]+ is selected as a hydrophobic cation and successfully assemble two new manganese based OIMHs of (TMSO)MnCl3 and (TMSO)MnBr3 through facile solid and liquid phase reaction methods. Remarkably, these halides exhibit strong red light emissions with high quantum yields recorded at 86.1% and 53.4%, respectively, originating from the octahedral [MnX6]4− based one‐dimensional (1D) [MnX3]− chain. Most significantly, these halides present extraordinary structural and luminescent stabilities toward continuous corrosion by humid air, water, and acid‐aqueous solution for more than one month, suggesting promising application prospects in extreme chemical environments. In‐depth Hirshfeld surface calculations demonstrate that the ultrahigh water‐stability benefits from the abundant hydrogen bonds and strong electrostatic interactions between [TMSO]+ and [MnX3]− ions, which provides an underlying insight into the stability mechanism. This water‐stability enhancement strategy represents a breakthrough structural engineering to rationally design more water‐stable OIMH. [ABSTRACT FROM AUTHOR]

Background: Identifying predictive biomarkers for allergen immunotherapy response is crucial for enhancing clinical efficacy. This study aims to identify such biomarkers in patients with allergic rhinitis (AR) undergoing subcutaneous immunotherapy (SCIT) for house dust mite allergy. Methods: The Tongji (discovery) cohort comprised 72 AR patients who completed 1‐year SCIT follow‐up. Circulating T and B cell subsets were characterized using multiplexed flow cytometry before SCIT. Serum immunoglobulin levels and combined symptom and medication score (CSMS) were assessed before and after 12‐month SCIT. Responders, exhibiting ≥30% CSMS improvement, were identified. The random forest algorithm and logistic regression analysis were used to select biomarkers and establish predictive models for SCIT efficacy in the Tongji cohort, which was validated in another Wisco cohort with 43 AR patients. Results: Positive SCIT response correlated with higher baseline CSMS, allergen‐specific IgE (sIgE)/total IgE (tIgE) ratio, and frequencies of Type 2 helper T cells, Type 2 follicular helper T (TFH2) cells, and CD23+ nonswitched memory B (BNSM) and switched memory B (BSM) cells, as well as lower follicular regulatory T (TFR) cell frequency and TFR/TFH2 cell ratio. The random forest algorithm identified sIgE/tIgE ratio, TFR/TFH2 cell ratio, and BNSM frequency as the key biomarkers discriminating responders from nonresponders in the Tongji cohort. Logistic regression analysis confirmed the predictive value of a combination model, including sIgE/tIgE ratio, TFR/TFH2 cell ratio, and CD23+ BSM frequency (AUC = 0.899 in Tongji; validated AUC = 0.893 in Wisco). Conclusions: A T‐ and B‐cell signature combination efficiently identified SCIT responders before treatment, enabling personalized approaches for AR patients. [ABSTRACT FROM AUTHOR]

While variation in mean annual precipitation (MAP) of the native habitat of a species has been shown to determine the ability of a species to resist a hydraulic decrease during drought, it remains unknown whether these variations in MAP also influence the ability of a species to recover and survive drought. Leaf hydraulic and gas exchange recovery following drought and the underlying mechanisms of these responses in six Caragana species from habitats along a large precipitation gradient were investigated during rehydration in a common garden. The gas exchange of species from arid habitats recovered more rapidly during rehydration after mild, moderate and severe drought stress treatments than species from humid habitats. The recovery of gas exchange was not associated with foliar abscisic acid concentration, but tightly related to the recovery of leaf hydraulic conductance (Kleaf). The recovery of Kleaf was associated with the loss of Kleaf during dehydration under mild and moderate drought stress, and to leaf xylem embolism formation under severe drought stress. Results pointed to the different ability to recover in gas exchange in six Caragana species post‐drought is associated with the MAP of the species in its native habitat. Summary Statement: Mean annual precipitation (MAP) has been shown to shape species' ability to resist a hydraulic dysfunction during drought. Our findings suggest that the ability to recover in gas exchange post‐drought as a strong driver in shaping species' distribution along a MAP gradient. [ABSTRACT FROM AUTHOR]

Stomatal closure is regulated by plant hormones and some small molecules to reduce water loss under stress conditions. Both abscisic acid (ABA) and polyamines alone induce stomatal closure; however, whether the physiological functions of ABA and polyamines are synergistic or antagonistic with respect to inducing stomatal closure is still unknown. Here, stomatal movement in response to ABA and/or polyamines was tested in Vicia faba and Arabidopsis thaliana, and the change in the signaling components under stomatal closure was analyzed. We found that both polyamines and ABA could induce stomatal closure through similar signaling components, including the synthesis of hydrogen peroxide (H2O2) and nitric oxide (NO) and the accumulation of Ca2+. However, polyamines partially inhibited ABA‐induced stomatal closure both in epidermal peels and in planta by activating antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), to eliminate the ABA‐induced increase in H2O2. These results strongly indicate that polyamines inhibit abscisic acid‐induced stomatal closure, suggesting that polyamines could be used as potential plant growth regulators to increase photosynthesis under mild drought stress. [ABSTRACT FROM AUTHOR]

Transplantation of a synthetic polymer nerve conduit carrying stem cells is promising for treating peripheral nerve injury. In this study, a micropatterned inner surface of polycaprolactone (PCL) nerve conduit cellularized with nasal respiratory mucosa‐derived ectoderm mesenchymal stem cells (EMSCs) is adopted for peripheral nerve regeneration. The PCL microstructure grating is fabricated by soft nanoimprint lithography (NIL), whose templates can be easily transferred from the Ebeam photoresist pattern. The most suitable microstructure is carefully chosen to support EMSCs alignment and nerve regeneration. In vitro, the micropatterned PCL nerve conduit greatly enhanced the directional alignment of EMSCs and the MBP and S100 expression of myelin proteins. Additionally, the micropatterned conduit preseeded with EMSCs significantly stimulated the axon‐directed extension of neural stem cells. In vivo, micropatterned PCL conduits cotransplanted with EMSCs enhanced motor function and promoted sciatic nerve regeneration and extension in a rat model of sciatic nerve defect. Taken together, this "all‐in‐one" nerve guidance conduit makes sciatic nerve regeneration and morphological repairing accelerated, which has a potential clinical application in neural tissue engineering. [ABSTRACT FROM AUTHOR]

Wildfires are becoming a global natural disaster under climate change. A worthwhile concern is that the rainfall thresholds that trigger debris flows in catchments affected by recent wildfires are much lower than those that trigger debris flows in catchments with similar environments but that have not experienced wildfires. In this study, we investigated a major post‐fire debris flow event in Xiangjiao catchment triggered by heavy rainfall in 2021. Through the combination of field observation, laboratory experiments and several numerical models (rainfall interception, infiltration, erosion and runoff models), the physical mechanistic analysis and numerical simulation of the post‐fire debris flow in Xiangjiao catchment was carried out. Results show that the simulated deposited area, erosion depth, and the occurrence time of debris‐flow initiation correlate well with the actual situation. It is demonstrated that the numerical simulation method used in this study can be used to effectively describe the characteristics of the initial and propagation stages of the post‐fire debris flow generated by runoff and provide important insights and guidance for the prediction and prevention of debris‐flow disasters in catchments affected by wildfire. Plain Language Summary: Wildfires are becoming more and more common under more frequent extreme weather. After the wildfire, the overall environment would be substantially changed, which will lead to more frequent debris‐flow disasters. Consequences of these changes are worthy to be deeply investigated. In this study, we investigated a major 2021 post‐fire debris flow event in Xiangjiao catchment, China, triggered by heavy rainfall. Through the combination of field observation, laboratory experiments, and numerical models, the physical mechanistic analysis and numerical simulation of the post‐fire debris flow in Xiangjiao catchment was carried out. Key Points: The mechanism of post‐fire debris flows caused by runoff in Xiangjiao catchment is analyzedUsing multiple numerical models and multi‐source data, the 2021 Xiangjiao post‐fire debris flow is simulatedThe numerical simulation results are analyzed and correlated well with the field investigation [ABSTRACT FROM AUTHOR]

BACKGROUND: Toxin–antitoxin (TA) systems are prevalent adaptive genetic elements in bacterial genomes, which can respond to environmental stress. While, few studies have addressed TA systems in probiotics and their roles in the adaptation to gastrointestinal transit (GIT) environments. RESULTS: The Weissella cibaria 018 could survive in pH 3.0–5.0 and 0.5–3.0 g L−1 bile salt, and its HigBA system responded to the bile salt stress, but not to acid stress. The toxin protein HigB and its cognate antitoxin protein HigA had 85.1% and 100% similarity with those of Lactobacillus plantarum, respectively, and they formed the stable tetramer HigB–(HigA)2–HigB structure in W. cibaria 018. When exposed to 1.5–3.0 g L−1 bile salt, the transcriptions of higB and higA were up‐regulated with 4.39–19.29 and 5.94–30.91 folds, respectively. Meanwhile, W. cibaria 018 gathered into a mass with 48.07% survival rate and its persister cells were found to increase 8.21% under 3.0 g L−1 bile salt. CONCLUSION: The HigBA TA system of W. cibaria 018 responded to the bile salt stress, but not to acid stress, which might offer novel perspectives to understand the tolerant mechanism of probiotics to GIT environment. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background and aims: Genomic and transcriptomic findings greatly broaden the biological knowledge regarding substance use. However, systematic convergence and comparison evidence of genome‐wide findings is lacking for substance use. Here, we combined all the genome‐wide findings from both substance use behavior and disorder (SUBD) and identified common and distinguishing genetic factors for different SUBDs. Methods: Systemic literature search for genome‐wide association (GWAS) and RNA‐seq studies of alcohol/nicotine/drug use behavior (partially meets or not reported diagnostic criteria) and alcohol use behavior and disorder (AUBD), nicotine use behavior and disorder (NUBD) and drug use behavior and disorder (DUBD) was performed using PubMed and the GWAS catalog. Drug use was focused upon cannabis, opioid, cocaine and methamphetamine use. GWAS studies required case–control or case/cohort samples. RNA‐seq studies were based on brain tissues. The genes which contained significant single nucleotide polymorphism (P ≤ 1 × 10−6) in GWAS and reported as significant in RNA‐seq studies were extracted. Pathway enrichment was performed by using Metascape. Gene interaction networks were identified by using the Protein Interaction Network Analysis database. Results: Total SUBD‐related 2910 genes were extracted from 75 GWAS studies (2 773 889 participants) and 17 RNA‐seq studies. By overlapping the genes and pathways of AUBD, NUBD and DUBD, four shared genes (CACNB2, GRIN2B, PLXDC2 and PKNOX2), four shared pathways [two Gene Ontology (GO) terms of 'modulation of chemical synaptic transmission', 'regulation of trans‐synaptic signaling', two Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways of 'dopaminergic synapse', 'cocaine addiction'] were identified (significantly higher than random, P < 1 × 10−5). The top shared KEGG pathways (Benjamini–Hochberg‐corrected P‐value < 0.05) in the pairwise comparison of AUBD versus DUBD, NUBD versus DUBD, AUBD versus NUBD were 'Epstein–Barr virus infection', 'protein processing in endoplasmic reticulum' and 'neuroactive ligand‐receptor interaction', respectively. We also identified substance‐specific genetic factors: i.e. ADH1B and ALDH2 were unique for AUBD, while CHRNA3 and CHRNA4 were unique for NUBD. Conclusions: This systematic review identifies the shared and unique genes and pathways for alcohol, nicotine and drug use behaviors and disorders at the genome‐wide level and highlights critical biological processes for the common and distinguishing vulnerability of substance use behaviors and disorders. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a cancer with extremely high mortality. Epithelial‐mesenchymal transition (EMT) may play an important role in the occurrence, invasion and prognosis of HCC; however, its relationship with immunity in HCC has not yet been studied. Therefore, we investigated the diagnostic and prognostic values of EMT and explored its potential connections with tumorigenic immune infiltrates in HCC. We first proposed a quantitative metric of EMT activity, the EMT score. After applying this metric to 20 datasets from the Integrative Molecular Database of Hepatocellular Carcinoma, the Cancer Genome Atlas, and the Gene Expression Omnibus, we explored the ability of the EMT score to stratify across sample types. We then applied the EMT score for survival analysis and to differentiate patients with/without vascular invasion to test its prognostic value. We also collected and calculated data on the abundance of immune cells and immune cell markers in HCC and investigated their correlations with EMT scores. Finally, we synthesized and analyzed 20 datasets and constructed an EMT‐gene‐immune linkage network. The results showed higher EMT scores in HCC samples than in cirrhotic and normal livers. The cases with higher EMT scores also showed poorer performance in terms of prognostic factors such as vascular invasion and overall survival time. Our research demonstrated a broad correlation between EMT and the tumor immune microenvironment, and we uncovered multiple potential linkers associated with both EMT and immunity. Studying EMT has clinical relevance and high diagnostic and prognostic value for HCC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Thiamethoxam is widely used to control pests in Chinese kale, popularly consumed leafy vegetables. The potential risk to the environment and human health has aroused much public concern. Therefore, it is important to investigate the degradation behavior, residue distribution and dietary risk assessment of thiamethoxam in Chinese kale. RESULTS: A sensitive analytical method for determination of thiamethoxam and its metabolite clothianidin residue in Chinese kale was established and validated through a quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique with ultra‐performance liquid chromatography tandem mass spectrometry (UPLC–MS/MS). The recoveries were 85.4–101.2% for thiamethoxam and 79.5–108.1% for clothianidin, with the relative standard deviations (RSDs) of 0.9–10.2% and 1.8–6.0%, respectively. For the dissipation kinetics, the data showed that thiamethoxam in Chinese kale was degraded with the half‐lives of 4.1 to 4.5 days. In the terminal residue experiments, the residues of thiamethoxam were 0.017–0.357 mg kg−1 after application 2–3 times with a preharvest interval (PHI) of 7 days under the designed dosages. The chronic and acute dietary exposure assessment risk quotient (RQ) values of thiamethoxam in Chinese kale for different Chinese consumers were 0.08–0.19% and 0.05–0.12%, respectively, and those of clothianidin were 0.01–0.04% and 0.02–0.04%, respectively, all of the RQ values were lower than 100%. CONCLUSION: Thiamethoxam in Chinese kale was rapidly degraded following first‐order kinetics models. The dietary risk of thiamethoxam and clothianidin through Chinese kale was negligible to consumers. The results from this study are important reference for Chinese governments to developing criteria for the safe and rational use of thiamethoxam, setting maximum residue levels (MRLs), monitoring the quality safety of agricultural products and protecting consumer health. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Genetic correlation analysis using LD score regression3 showed MD and HD were significantly correlated ( I r SB g sb i = 0.8618, I p i = 7.361e-5), but not for HD and AD, MD and AD. This work presented a significant correlation between heroin and methamphetamine dependence (HD and MD) which distinguished with alcohol dependence (AD) at the genome-wide level. Genome-wide association meta-analyses identify novel genetic risk loci and polygenic phenotype associations for heroin, methamphetamine and alcohol dependences. [Extracted from the article]

It has been suggested that a trade‐off between hydraulic efficiency and safety is related to drought adaptation across species. However, whether leaf hydraulic efficiency is sacrificed for safety during woody resprout regrowth after crown removal is not well understood. We measured leaf water potential (ψleaf) at predawn (ψpd) and midday (ψmid), leaf maximum hydraulic conductance (Kleaf‐max), ψleaf at induction 50% loss of Kleaf‐max (KleafP50), leaf area‐specific whole‐plant hydraulic conductance (LSC), leaf vein structure and turgor loss point (πtlp) in 1‐ to 13‐year‐old resprouts of the aridland shrub (Caragana korshinskii). ψpd was similar, ψmid and KleafP50 became more negative, and Kleaf–max decreased in resprouts with the increasing age; thus, leaf hydraulic efficiency clearly traded off against safety. The difference between ψmid and KleafP50, leaf hydraulic safety margin, increased gradually with increasing resprout age. More negative ψmid and KleafP50 were closely related to decreasing LSC and more negative πtlp, respectively, and the decreasing Kleaf‐max arose from the lower minor vein density and the narrower midrib xylem vessels. Our results showed that a clear trade‐off between leaf hydraulic efficiency and safety helps C. korshinskii resprouts adapt to increasing water stress as they approach final size. A trade‐off between leaf hydraulic efficiency and safety is proposed to be related to drought adaptation, but it is still under debate. Here, leaf hydraulic efficiency clearly traded off against safety in resprouts of Caragana korshinskii, thus helping resprouts adapt to increasing water stress. [ABSTRACT FROM AUTHOR]

Use of genetically engineered plants that express insecticidal Cry proteins derived from Bacillus thuringiensis (Bt) have been proven efficacious for managing lepidopteran pests. However, in some cases herbivores that are not targeted by the Bt trait have increased in importance. It has been suggested that reduced caterpillar damage to Bt crops could lead to decreased levels of induced plant defensive compounds which might benefit other non‐target herbivores. Here we investigated the potential effect of reduced damage by larvae of Mythimna separata on aphid populations in Bt corn. We compared the performance of Rhopalosiphum maidis feeding on non‐Bt corn plants that had been infested by M. separata larvae or were uninfested. The results showed that caterpillar‐infested corn plants significantly reduced the fitness of R. maidis leading to a prolonged nymphal development time, reduced adult longevity and fecundity compared to uninfested plants. Consequently, the population growth rate of corn aphids feeding on caterpillar‐infested corn plants was significantly lower than on uninfested plants. As expected, the aphids performed significantly better on Lepidoptera‐resistant Bt corn than on non‐Bt corn when plants were infested with M. separata, since the caterpillars caused very little damage to the Bt plants. The current findings indicate that reduced M. separata infestation could benefit aphid development in Bt corn. Bt corn has the potential to be commercialized in China in the near future and aphids and other non‐target pests should be monitored in the farming fields. [ABSTRACT FROM AUTHOR]

Background and Objectives: COVID‐19‐related quarantine and stress have likely escalated the crisis of Internet addiction. This study aimed to determine the impact of the COVID‐19 pandemic on Internet use and related risk factors among the general public in China. Methods: A large‐sample cross‐sectional online survey was conducted from March 24 to April 30, 2020, in China, and 20,472 participants completed the survey. We investigated the prevalence and severity of Internet addiction based on the Internet Addiction Test (IAT), and explored the risk factors related to increases in time spent on Internet use and severity of Internet addiction, as well as severe Internet addiction. Results: The overall prevalence of Internet addiction was 36.7% among the general population during the pandemic, and that of severe Internet addiction was 2.8%, according to IAT scores. Time spent on recreational Internet use had significantly increased during the pandemic, and almost half of participants reported increases in the severity of Internet addiction. Risk factors for increases in time spent on Internet use and severity of Internet addiction and severe Internet addiction included having fewer social supporters, perceiving pressure and impact on mental health status due to COVID‐19, and being over‐engaged in playing videogames. Discussion and Conclusions: The COVID‐19 pandemic adversely impacted Internet use and increased the prevalence and severity of Internet addiction among the general population in China, especially in vulnerable populations. Scientific Significance: This study provides evidence for policymakers to refine public health policies to control the pandemic and make efforts to provide population‐specific prevention and interventions for people at risk of developing Internet addiction. (Am J Addict 2021;00:00–00) [ABSTRACT FROM AUTHOR]

Investigating plant morphological traits can provide insights into plant drought tolerance. To date, many papers have focused on plant hydraulic responses to drought during dehydration, but atmospheric water absorption by trichomes to mitigate drought stress by influencing leaf hydraulics in plant species that inhabit arid environments has been largely ignored. The experiment in this study was designed to assess how dew absorbed by leaf trichomes helps Caragana korshinskii withstand drought. The results showed that under a drought stress and dew (DS & D) treatment, C. korshinskii displayed a strong capacity to absorb dew with trichomes; exhibited slow decreases in leaf water potential (Ψleaf), leaf hydraulic conductivity (Kleaf), and gas exchange; experienced 50% Kleaf and gas exchange losses at lower relative soil water content levels than plants treated with drought stress and no dew (DS & ND); and experienced 50% Kleaf loss (Kleaf P50) at similar Ψleaf levels as DS & ND plants. Its congener C. sinica, which does not have leaf trichomes, displayed little ability to absorb dew under drought stress and did not show any remarkable improvement in the above parameters under the DS & D treatment. Our results indicated that leaf trichomes are important epidermal dew-uptake structures that assist in partially sustaining the leaf hydraulic assimilation system, mitigate the adverse effects of drought stress and contribute to the distribution of C. korshinskii in arid environments. [ABSTRACT FROM AUTHOR]

Summary: Plants control water‐use efficiency (WUE) by regulating water loss and CO2 diffusion through stomata. Variation in stomatal control has been reported among lineages of vascular plants, thus giving rise to the possibility that different lineages may show distinct WUE dynamics in response to water stress.Here, we compared the response of gas exchange to decreasing leaf water potential among four ferns and nine seed plant species exposed to a gradually intensifying water deficit. The data collected were combined with those from 339 phylogenetically diverse species obtained from previous studies.In well‐watered angiosperms, the maximum stomatal conductance was high and greater than that required for maximum WUE, but drought stress caused a rapid reduction in stomatal conductance and an increase in WUE in response to elevated concentrations of abscisic acid. However, in ferns, stomata did not open beyond the optimum point corresponding to maximum WUE and actually exhibited a steady WUE in response to dehydration. Thus, seed plants showed improved photosynthetic WUE under water stress.The ability of seed plants to increase WUE could provide them with an advantage over ferns under drought conditions, thereby presumably increasing their fitness under selection pressure by drought. [ABSTRACT FROM AUTHOR]

Drought is a cyclical phenomenon in natural environments. During dehydration, stomatal closure is mainly regulated by abscisic acid (ABA) dynamics that limit transpiration in seed plants, but following rehydration, the mechanism of gas exchange recovery is still not clear. In this study, leaf water potential (ψleaf), stomatal conductance (gs), leaf hydraulic conductance (Kleaf), foliar ABA level, ethylene emission rate in response to dehydration and rehydration were investigated in four Caragana species with isohydric (Caragana spinosa and C. pruinosa) and anisohydric (C. intermedia and C. microphylla) traits. Two isohydric species with ABA‐induced stomatal closure exhibited more sensitive gs and Kleaf to decreasing ψleaf than two anisohydric species which exhibited a switch from ABA to water potential‐driven stomatal closure during dehydration. Following rehydration, the recovery of gas exchange was not associated with a decrease in ABA level but was strongly limited by the degradation of the ethylene emission rate in all species. Furthermore, two anisohydric species with low drought‐induced ethylene production exhibited more rapid recovery in gas exchange upon rehydration. Our results indicated that ethylene is a key factor regulating the drought‐recovery ability in terms of gas exchange, which may shape species adaptation to drought and potential species distribution. Drought is a cyclical phenomenon in natural environments. During dehydration, stomatal closure is mainly regulated by abscisic acid (ABA) dynamics that limit transpiration in seed plants, but the mechanisms of gas exchange recovery are still not clear following rehydration. The results in this study indicate that ethylene is a key factor regulating the drought‐recovery ability in terms of gas exchange, which may shape species adaptation to drought and potential species distribution. [ABSTRACT FROM AUTHOR]

Summary: Clarifying the coordination of leaf hydraulic traits with gas exchange across closely‐related species adapted to varying rainfall can provide insights into plant habitat distribution and drought adaptation.The leaf hydraulic conductance (Kleaf), stomatal conductance (gs), net assimilation (A), vein embolism and abscisic acid (ABA) concentration during dehydration were quantified, as well as pressure–volume curve traits and vein anatomy in 10 Caragana species adapted to a range of mean annual precipitation (MAP) conditions and growing in a common garden.We found a positive correlation between Ψleaf at 50% loss of Kleaf (KleafP50) and maximum Kleaf (Kleaf‐max) across species. Species from low‐MAP environments exhibited more negative KleafP50 and turgor loss point, and higher Kleaf‐max and leaf‐specific capacity at full turgor, along with higher vein density and midrib xylem per leaf area, and a higher ratio of Kleaf‐max : maximum gs. Tighter stomatal control mediated by higher ABA accumulation during dehydration in these species resulted in an increase in hydraulic safety and intrinsic water use efficiency (WUEi) during drought.Our results suggest that high hydraulic safety and efficiency combined with greater stomatal sensitivity triggered by ABA production and leading to greater WUEi provides drought tolerance in Caragana species adapted to low‐MAP environments. [ABSTRACT FROM AUTHOR]

The polypnictide complexes of rare earth cations have drawn the attention of the scientific community for their uncommon bonding modes and potential applications. Herein, we present a systematic and comprehensive summary on recent advances in the field of rare earth polypnictides, focusing on their synthesis, structures, and reactivities. The structural stabilizing effects imposed by the electropositive rare earth cations as well as the reducing capability of rare earth precursors in the synthesis of these polypnictide complexes are described in this review. We also disscuss in detail the bonding interactions and coordination modes between rare earth cations and polypnictide clusters as well as the similarities and the peculiarity of some structures. [ABSTRACT FROM AUTHOR]

The chemical bonding of Zintl clusters is still an evolving and hot topic in modern chemistry. In this paper we synthesized a novel [K([2.2.2]crypt)]4[In8Bi13] complex in a condensed phase. The quantum chemical calculations and X‐ray data revealed that the compound consists of the 1:1 mixture of [Bi@In8Bi12]3− and [Bi@In8Bi12]5− clusters. To the date, those clusters are the largest binary clusters composed of In and Bi elements. Herein, we introduce a spherical aromatic description of chemical bonding for such clusters. We show through AdNDP, ELF, and induced magnetic field and quantitative NICS analyzes that both clusters are spherically aromatic which explains their high symmetry, stability, and peculiar magnetic properties. We believe that this work will help researchers in the further development and understanding of chemical bonding in Zintl clusters. [ABSTRACT FROM AUTHOR]

Abstract: Two series of isostructural lanthanide coordination complexes, namely, LIFM‐42(Ln) (Ln=Eu, Tb, Gd, in which LIFM stands for the Lehn Institute of Functional Materials) and LIFM‐43(Ln) (Ln=Er, Yb), were synthesized through the self‐assembly of an excited‐state intramolecular proton transfer (ESIPT) ligand, 5‐[2‐(5‐fluoro‐2‐hydroxyphenyl)‐4,5‐bis(4‐fluorophenyl)‐1H‐imidazol‐1‐yl]isophthalic acid (H2hpi2cf), with different lanthanide ions. In the coordination structures linked by the ligands and oxo‐bridged LnIII2 clusters (for LIFM‐42(Ln) series) or isolated LnIII ions (for LIFM‐43(Ln) series), the ESIPT ligand can serve as both the host and antenna for protecting and sensitizing the photoluminescence (PL) of LnIII ions. Meanwhile, the −OH⋅⋅⋅N active sites on the ligands are vacant, which provides availability to systematically explore the PL behavior of Ln complexes with ESIPT interference. Based on the accepting levels of different lanthanide ions, energy transfer can occur from the T1(K*) or T1(E*) (K*=excited keto form, E*=excited enol form) excited states of the ligand. Furthermore, the sensitized lanthanide luminescence in both visible and near‐infrared regions, as well as the remaining K* emission of the ligand, can be modulated by the ESIPT responsiveness to different solvents, anions, and temperature. [ABSTRACT FROM AUTHOR]

Background and Purpose: Mirabegron has been classified as a β3 -adrenoceptor agonist approved for overactive bladder syndrome. We investigated possible cardiac effects of mirabegron in the absence or presence of β-adrenoceptor subtype antagonists. In view of its phenylethanolamine structure, we investigated whether mirabegron has indirect sympathomimetic activity by using neuronal uptake blockers.Experimental Approach: Right atrial trabeculae, from non-failing hearts, were paced and contractile force measured at 37°C. Single concentrations of mirabegron were added in the absence or presence of the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX), β3 (L-748,337), β1 (CGP 20712A), β2 (ICI 118,551) -adrenoceptor antagonists, neuronal uptake inhibitors desipramine or phenoxybenzamine.Key Results: Mirabegron significantly increased contractile force in human right atrium (1 μM, 7.6 ± 2.6%, n = 7; 10 μM, 10.2 ± 1.5%, n = 22 compared with (-)-isoprenaline P < 0.05). In the presence of IBMX, mirabegron (10 μM) caused a greater contraction. L-748,337 (100 nM) had no effect on the increase in contractile force caused by mirabegron (10 μM). In contrast, mirabegron (10 μM) reduced contractile force in the presence of CGP 20712A, which was not affected by L-748,337 (100 nM) or ICI 118,551 (50 nM). Mirabegron (10 μM) also reduced contractile force in the presence of desipramine or phenoxybenzamine.Conclusions and Implications: Mirabegron increases human atrial force through β1 - but not β3 -adrenoceptors. Desipramine and phenoxybenzamine block neuronal uptake and conceivably prevent mirabegron from releasing noradrenaline. A non-specific cardiodepressant effect is not mediated through β3 (or β2 )-adrenoceptors, consistent with lack of β3 -adrenoceptor function on human atrial contractility. [ABSTRACT FROM AUTHOR]

Background Cone-beam computed tomography can accurately show anatomic structure of intrabony nerve canals in mandibular interforaminal region. Purpose The aim was to evaluate the characteristics of intrabony nerve canals in mandibular interforaminal region by using cone-beam computed tomography (CBCT) and determine a safe zone for implant and bone harvesting. Materials and methods Hemimandibles (824) CBCT images were obtained. The length of the anterior loop (AL), the length and diameter of the mandibular incisive canal (MIC) and its spatial distance in various landmarks were measured. Results The prevalence of the AL was 93.57%, and the MIC was 97.33%. The mean lengths of the anterior extension of the anterior loop (aAL), caudal extension of the anterior loop (cAL) and the MIC were 2.53 ± 1.27 mm, 6.04 ± 1.66 mm, 9.97 ± 5.15 mm, respectively. The MIC was closer to buccal border and inferior margin of mandible. The length of the AL and diameter of the MIC varied with gender. Conclusions The safe zone recommended for implant surgery is 4 mm anterior and 8 mm inferior to the mental foramen, and 10 mm above the inferior margin of mandible. The chin bone should be harvested at least 10 mm below the tooth apices along with a limited depth of 4 mm. [ABSTRACT FROM AUTHOR]

A novel scheme is proposed to locate the dispersive region, whose location is essential for parallel echo cancellation. In the scheme, a first filter adapts to a subsampled version of the input signal to roughly identify the impulse response. After each adaptation, a squaring function and a moving window integration procedure are performed on the first filter, and the region with the maximum integration value is considered to be the dispersive region. Finally, a second short filter is used to precisely identify the active coefficients belonging to the located dispersive region to implement the actual echo cancellation. Simulation results suggest that the parallel structure improves its convergence speed 3 times and its computation can be reduced by 3/8 compared with the traditional NLMS algorithm by decreasing the filter length. Due to the more accurate estimate of the location, the misalignment noise of the proposed algorithm is at least 10 dB lower than that of the conventional dispersive region locating algorithm. Moreover, the proposed algorithm based on the parallel structure outperforms other sparse adaptive algorithms in all aspects. [ABSTRACT FROM AUTHOR]

Phytoremediation as a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants is becoming an increasingly important objective in plant research. In this study, biological cycles of five nutrient elements (N, P, K, Ca, and Mg) and eight heavy metal elements (Fe, Cu, Zn, Mn, Cd, Ni, Pb and Co) were examined in young paniculed goldraintree ( Koelreuteria paniculata Laxm) and common elaeocarpus (Elaeocarpus decipens) mixed stands in an abandoned mining area. We found that after vegetation restoration in abandoned mining areas, the organic matter and concentrations of nutrient elements were significantly increased and the heavy metal elements were significantly decreased, the annual retention, uptake and return were 75.0, 115.4, and 40.3 kg/hm2 for nutrient elements, and 1 878.0, 3 231.0 and 1 353.0 g/hm2 for heavy metal elements, respectively, with the utilization coefficient, cycling coefficient and turnover rate of 0.92, 0.35 and 0.32 for nutrient elements, and 1.24, 0.42 and 1.92 for heavy metal elements, respectively. Our results suggested that the vegetation restoration in abandoned mining areas had significant effects in improving environmental conditions, enhancing soil available nutrients, and ensuring human health. [ABSTRACT FROM AUTHOR]

Bimetallic macrocyclic complexes have attracted the attention of chemists and various organic ligands have been used as molecular building blocks, but supramolecular complexes based on semi-rigid organic ligands containing 1,2,4-triazole have remained rare until recently. It is easier to obtain novel topologies by making use of asymmetric semi-rigid ligands in the self-assembly process than by making use of rigid ligands. A new semi-rigid ligand, 3-[(pyridin-4-ylmethyl)sulfanyl]-5-(quinolin-2-yl)-4 H-1,2,4-triazol-4-amine ( L), has been synthesized and used to generate two novel bimetallic macrocycle complexes, namely bis{μ-3-[(pyridin-4-ylmethyl)sulfanyl]-5-(quinolin-2-yl)-4 H-1,2,4-triazol-4-amine}bis[(methanol-κ O)(nitrato-κ2 O, O′)nickel(II)] dinitrate, [Ni2(NO3)2(C17H14N6S)2(CH3OH)2](NO3)2, (I), and bis{μ-3-[(pyridin-4-ylmethyl)sulfanyl]-5-(quinolin-2-yl)-4 H-1,2,4-triazol-4-amine}bis[(methanol-κ O)(nitrato-κ2 O, O′)zinc(II)] dinitrate, [Zn2(NO3)2(C17H14N6S)2(CH3OH)2](NO3)2, (II), by solution reactions with the inorganic salts M(NO3)2 ( M = Ni and Zn, respectively) in mixed solvents. In (I), two NiII cations with the same coordination environment are linked by L ligands through Ni-N bonds to form a bimetallic ring. Compound (I) is extended into a two-dimensional network in the crystallographic ac plane via N-H...O, O-H...N and O-H...O hydrogen bonds, and neighbouring two-dimensional planes are parallel and form a three-dimensional structure via π-π stacking. Compound (II) contains two bimetallic rings with the same coordination environment of the ZnII cations. The ZnII cations are bridged by L ligands through Zn-N bonds to form the bimetallic rings. One type of bimetallic ring constructs a one-dimensional nanotube via O-H...O and N-H...O hydrogen bonds along the crystallographic a direction, and the other constructs zero-dimensional molecular cages via O-H...O and N-H...O hydrogen bonds. They are interlinked into a two-dimensional network in the ac plane through extensive N-H...O hydrogen bonds, and a three-dimensional supramolecular architecture is formed via π-π interactions between the centroids of the benzene rings of the quinoline ring systems. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, a novel type of macromolecular prodrug, N-galactosylated chitosan (GC)−5-fluorouracil acetic acid (FUA) conjugate based nanoparticles, was designed and synthesized as a carrier for hepatocellular carcinoma drug delivery. The GC-FUA nanoparticles were produced by an ionic crosslinking method based on the modified ionic gelation of tripolyphosphate with GC-FUA. The structure of the as-prepared GC-FUA was characterized by Fourier transform infrared and 1H-NMR analyses. The average particle size of the GC-FUA nanoparticles was 160.1 nm, and their drug-loading content was 21.22 ± 2.7% ( n = 3). In comparison with that of the freshly prepared nanoparticles, this value became larger after 7 days because of the aggregation of the GC-FUA nanoparticles. An in vitro drug-release study showed that the GC-FUA nanoparticles displayed a sustained-release profile compared to 5-fluorouracil-loaded GC nanoparticles. All of the results suggest that the GC-FUA nanoparticles may have great potential for anti-liver-cancer applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42625. [ABSTRACT FROM AUTHOR]

Three coordination complexes with CuI centres have been prepared using the symmetrical flexible organic ligands 1,3-bis{[5-(quinolin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}propane ( L1) and 1,4-bis{[5-(quinolin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}butane ( L2). Crystallization of L1 with Cu(SO3CF3)2 and of L2 with Cu(BF4)2 and Cu(ClO4)2 in a CH2Cl2/CH3OH mixed-solvent system at room temperature afforded the coordination complexes catena-poly[[copper(I)-μ-1,3-bis{[5-(quinolin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}propane] methanesulfonate dichloromethane 0.6-solvate], {[Cu(C25H18N6O2S2)](CF3SO3)·0.6CH2Cl2} n, (I), bis(μ-1,4-bis{[5-(quinolin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}butane)dicopper(I) bis(tetrafluoridoborate)-dichloromethane-methanol (1/1.5/1), [Cu2(C26H20N6O2S2)2](BF4)2·1.5CH2Cl2·CH3OH, (II), and bis(μ-1,4-bis{[5-(quinolin-2-yl)-1,3,4-oxadiazol-2-yl]sulfanyl}butane)dicopper(I) bis(perchlorate)-dichloromethane-methanol (1/2/1), [Cu2(C26H20N6O2S2)2](ClO4)2·2CH2Cl2·CH3OH, (III). Under the control of the dumbbell-shaped CF3SO3− anion, complex (I) forms a one-dimensional chain and neighbouring chains form a spiral double chain. Under the control of the regular tetrahedron-shaped BF4− and ClO4− anions, complexes (II) and (III) have been obtained as bimetallic rings, which further interact viaπ-π interactions to form two-dimensional networks. The anions play a decisive role in determining the arrangement of these discrete molecular complexes in the solid state. [ABSTRACT FROM AUTHOR]

Two different one-dimensional supramolecular chains with CoII cations have been synthesized based on the semi-rigid ligand 2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline ( L), obtained by condensation of 2-(1 H-benzimidazol-2-yl)quinoline and 4-(chloromethyl)pyridine hydrochloride. Starting from different CoII salts, two new compounds have been obtained, viz. catena-poly[[[dinitratocobalt(II)]-μ-2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline] dichloromethane monosolvate acetonitrile monosolvate], {[Co(NO3)2(C22H16N4)]·CH2Cl2·CH3CN} n, (I) and catena-poly[[[dichloridocobalt(II)]-μ-2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline] methanol disolvate], {[CoCl2(C22H16N4)]·2CH3OH} n, (II). In (I), the CoII centres lie in a distorted octahedral [CoN3O3] coordination environment. {Co(NO3)2 L} n units form one-dimensional helical chains, where the L ligand has different directions of twist. The helical chains stack together via interchain π-π interactions to form a two-dimensional sheet, and another type of π-π interaction further connects neighbouring sheets into a three-dimensional framework with hexagonal channels, in which the acetonitrile molecules and disordered dichloromethane molecules are located. In (II), the CoII centres lie in a distorted trigonal-bipyramidal [CoCl2N3] coordination environment. {CoCl2 L} n units form one-dimensional chains. The chains interact via C-H...π and C-H...Cl interactions. The result is that two-dimensional sheets are generated, which are further linked into a three-dimensional framework via interlayer C-H...Cl interactions. When viewed down the crystallographic b axis, the methanol solvent molecules are located in an orderly manner in wave-like channels. [ABSTRACT FROM AUTHOR]

Two different one-dimensional supramolecular chains with CoII cations have been synthesized based on the semi-rigid ligand 2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline ( L), obtained by condensation of 2-(1 H-benzimidazol-2-yl)quinoline and 4-(chloromethyl)pyridine hydrochloride. Starting from different CoII salts, two new compounds have been obtained, viz. catena-poly[[[dinitratocobalt(II)]-μ-2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline] dichloromethane monosolvate acetonitrile monosolvate], {[Co(NO3)2(C22H16N4)]·CH2Cl2·CH3CN} n, (I) and catena-poly[[[dichloridocobalt(II)]-μ-2-[1-(pyridin-4-ylmethyl)-1 H-benzimidazol-2-yl]quinoline] methanol disolvate], {[CoCl2(C22H16N4)]·2CH3OH} n, (II). In (I), the CoII centres lie in a distorted octahedral [CoN3O3] coordination environment. {Co(NO3)2 L} n units form one-dimensional helical chains, where the L ligand has different directions of twist. The helical chains stack together via interchain π-π interactions to form a two-dimensional sheet, and another type of π-π interaction further connects neighbouring sheets into a three-dimensional framework with hexagonal channels, in which the acetonitrile molecules and disordered dichloromethane molecules are located. In (II), the CoII centres lie in a distorted trigonal-bipyramidal [CoCl2N3] coordination environment. {CoCl2 L} n units form one-dimensional chains. The chains interact via C-H...π and C-H...Cl interactions. The result is that two-dimensional sheets are generated, which are further linked into a three-dimensional framework via interlayer C-H...Cl interactions. When viewed down the crystallographic b axis, the methanol solvent molecules are located in an orderly manner in wave-like channels. [ABSTRACT FROM AUTHOR]

Two new symmetric double-armed oxadiazole-bridged ligands, 4-methyl-{5-[5-methyl-2-(pyridin-3-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-3-carboxylate ( L1) and 4-methyl-{5-[5-methyl-2-(pyridin-4-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-4-carboxylate ( L2), were prepared by the reaction of 2,5-bis(2-hydroxy-5-methylphenyl)-1,3,4-oxadiazole with nicotinoyl chloride and isonicotinoyl chloride, respectively. Ligand L1 can be used as an organic clip to bind CuII cations and generate a molecular complex, bis(4-methyl-{5-[5-methyl-2-(pyridin-3-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-3-carboxylate)bis(perchlorato)copper(II), [Cu(ClO4)2(C28H20N4O5)2], (I). In compound (I), the CuII cation is located on an inversion centre and is hexacoordinated in a distorted octahedral geometry, with the pyridine N atoms of two L1 ligands in the equatorial positions and two weakly coordinating perchlorate counter-ions in the axial positions. The two arms of the L1 ligands bend inward and converge at the CuII coordination point to give rise to a spirometallocycle. Ligand L2 binds CuI cations to generate a supramolecule, diacetonitriledi-μ3-iodido-di-μ2-iodido-bis(4-methyl-{5-[5-methyl-2-(pyridin-4-ylcarbonyloxy)phenyl]-1,3,4-oxadiazol-2-yl}phenyl pyridine-4-carboxylate)tetracopper(I), [Cu4I4(CH3CN)2(C28H20N4O5)2], (II). The asymmetric unit of (II) indicates that it contains two CuI atoms, one L2 ligand, one acetonitrile ligand and two iodide ligands. Both of the CuI atoms are four-coordinated in an approximately tetrahedral environment. The molecule is centrosymmetric and the four I atoms and four CuI atoms form a rope-ladder-type [Cu4I4] unit. Discrete units are linked into one-dimensional chains through π-π interactions. [ABSTRACT FROM AUTHOR]

Understanding the dynamics and underlying mechanism of carbon exchange between terrestrial ecosystems and the atmosphere is one of the key issues in global change research. In this study, we quantified the carbon fluxes in different terrestrial ecosystems in China, and analyzed their spatial variation and environmental drivers based on the long-term observation data of China FLUX sites and the published data from other flux sites in China. The results indicate that gross ecosystem productivity ( GEP), ecosystem respiration ( ER), and net ecosystem productivity ( NEP) of terrestrial ecosystems in China showed a significantly latitudinal pattern, declining linearly with the increase of latitude. However, GEP, ER, and NEP did not present a clear longitudinal pattern. The carbon sink functional areas of terrestrial ecosystems in China were mainly located in the subtropical and temperate forests, coastal wetlands in eastern China, the temperate meadow steppe in the northeast China, and the alpine meadow in eastern edge of Qinghai-Tibetan Plateau. The forest ecosystems had stronger carbon sink than grassland ecosystems. The spatial patterns of GEP and ER in China were mainly determined by mean annual precipitation ( MAP) and mean annual temperature ( MAT), whereas the spatial variation in NEP was largely explained by MAT. The combined effects of MAT and MAP explained 79%, 62%, and 66% of the spatial variations in GEP, ER, and NEP, respectively. The GEP, ER, and NEP in different ecosystems in China exhibited 'positive coupling correlation' in their spatial patterns. Both ER and NEP were significantly correlated with GEP, with 68% of the per-unit GEP contributed to ER and 29% to NEP. MAT and MAP affected the spatial patterns of ER and NEP mainly by their direct effects on the spatial pattern of GEP. [ABSTRACT FROM AUTHOR]

AgCl/poly(methyl methacrylate) (PMMA) organic-inorganic hybrid membrane has been synthesized by reverse microemulsion polymerization using triblock copolymer polyoxyethylene-polyoxypropylene-polyoxyethylene as surfactant and MMA as oil phase. The results by ultraviolet-visible spectrum, transmission electron microscopy, and scanning electron microscopy showed that small AgCl nanoparticles distributed well in the F127 microemulsions and hybrid membranes at low reactant concentration. AgCl nanoparticles in the microemulsion became smaller with increasing reactant concentration. However, AgCl nanoparticles aggregated obviously in hybrid membranes, when reactant concentration was more than 0.15 mol L−1. The performance of different hybrid membranes for separation of the benzene and cyclohexane was measured. The results indicated that the separation performance of membrane was promoted obviously due to presence of more well-dispersed AgCl particles in hybrid membranes. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Eight new C21 steroidal glycosides, named wilfosides A-H ( 1- 8, resp.), along with one known compound wilfoside KIN ( 9), were isolated from the roots of Cynanchum wilfordii. The structures of the new glycosides were determined on the basis of spectroscopic analysis, including 1D- and 2D-NMR, and ESI-MS techniques, as well as by comparison of the spectral data with those of related compounds. [ABSTRACT FROM AUTHOR]

Different defense mechanisms of three spring wheat ( Triticum aestivum L.) varieties were studied by withholding watering in well-watered pots to gradually increase water deficit of plants grown in containers. The strategies of plant adaptation were divided into three phases according to the severity of drought: first, a positive defense phase that started from commencement of non-hydraulic root-sourced signals (nHRS) and ended at onset of hydraulic root-sourced signals (HRS)—the plant responded to imminent drought by decreasing stomatal aperture to lessen water loss and no membrane injury occurred. The second defense phase occurred between the onset of HRS and temporary wilting (TW), characterized by enhancement of reactive oxygen species (ROS), marked enzyme activity and increased MDA content. Mild lipid membrane peroxidation came mainly from a dynamic imbalance between free radical production and enzymatic defense reaction, which indicated that injury by ROS had not been completely repaired by increasing enzymatic activity. The third defense phase was from TW to permanent wilting (PW), the synthesis of SOD and CAT during TW could not deal with the collapse of antioxidant enzymes, and SOD and CAT activities began to decrease, which caused the excessive ROS production and thus serious membrane lipid peroxidation. The defense strategies to drought are similar among the varieties, but modern varieties LC8275 and GY602 bred after 1975 had relatively higher defense levels at all three defense phases, which suggest that modern varieties are more resistant than old ones, and artificial selection would lead to a different direction in evolution from natural selection. [ABSTRACT FROM AUTHOR]

The self-thinning rule defines a straight upper boundary line on log-log scales for all possible combinations of mean individual biomass and density in plant populations. Recently, the traditional slope of the upper boundary line, −3/2, has been challenged by −4/3 which is deduced from some new mechanical theories, like the metabolic theory. More experimental or field studies should be carried out to identify the more accurate self-thinning exponent. But it's hard to obtain the accurate self-thinning exponent by fitting to data points directly because of the intrinsic problem of subjectivity in data selection. The virtual dynamic thinning line is derived from the competition-density (C-D) effect as the initial density tends to be positive infinity, avoiding the data selection process. The purpose of this study was to study the relationship between the virtual dynamic thinning line and the upper boundary line in simulated plant stands. Our research showed that the upper boundary line and the virtual dynamic thinning line were both straight lines on log-log scales. The slopes were almost the same value with only a very little difference of 0.059, and the intercept of the upper boundary line was a little larger than that of the virtual dynamic thinning line. As initial size and spatial distribution patterns became more uniform, the virtual dynamic thinning line was more similar to the upper boundary line. This implies that, given appropriate parameters, the virtual dynamic thinning line may be used as the upper boundary line in simulated plant stands. [ABSTRACT FROM AUTHOR]

Background/Aims: Injury and activation of tubular proximal epithelial cells (TEC) play central roles in renal tubulointerstitial fibrosis (TIF), but its mechanisms remain obscure. Interleukin 18 (IL-18) is overproduced during chronic kidney diseases (CKD), but how IL-18 affects the biological behaviour of TEC is not clear. The aim of the present study is to reveal the role of IL-18 in renal TIF. Methods: The expressions of IL-18 and IL-18 receptor in TEC were detected by immunohistochemical staining in vivo and by reverse transcriptase polymerase chain reaction (RT-PCR) in vitro. TEC line (HK-2 cells) were incubated without or with IL-18. Cell proliferation and cell cycle were evaluated by methyl thiazolyl tetrazolium assay and flow cytometric analysis, respectively. Cell apoptosis was assessed by Hoechst 33258 staining. Expression of α-smooth muscle actin was evaluated by RT-PCR, immunocytochemical staining and flow cytometric analysis, respectively. Type I collagen, fibronectin, MCP-1 and RANTES in cultured supernatants were measured by enzyme-linked immunosorbent assay. Results: IL-18 expression in TEC increased significantly in CKD state. IL-18 receptor was constitutively expressed in normal proximal TEC, and its expression increased strongly in CKD state. Proliferation and cell cycle of HK-2 cells were not affected by IL-18. Cell apoptosis, α-smooth muscle actin expression, type I collagen and fibronectin production as well as MCP-1 secretion were promoted by IL-18 in dosage- and/or time-dependent manners, but RANTES secretion was not affected. Conclusion: IL-18 may play a crucial role in the process of TIF by promoting TEC injury and activation, and could be a target of the therapeutic approaches against TIF. [ABSTRACT FROM AUTHOR]

The article presents a study on the cocrystallization of two tautomers, the enol-imine form 4-(1-{[4-(dimethylamino)benzylidene]hydrazono}ethyl)benzene-1,3-diol and the keto-amine form 6-[(E)-1-{[4-(dimethylamino)benzylidene]hydrazino}ethylidene]-3-hydroxycyclohexa-2,4-dien-1-one. These tautomers are developed by proton transfer between the hydroxy O atom and the imine N atom of a new Schiff base compound. An overview of a cocrystallization experiment on the two tautomers is also offered.

This article prepares and studies a series of chitosan‐modified core–shell SiO2‐acidic polymer multiple crosslinked membranes (modified membranes). The preparation process is simple, low cost, and environmentally friendly. The multiple crosslinking enhances the thermal stability and mechanical strength of membranes. TGA shows that the 10% weight loss temperatures of modified membranes are above 300 °C. Compared with water uptake, the methanol absorption of modified membranes is lower and decreases with increasing methanol concentration, which is very beneficial to their use in direct‐methanol fuel cells. The lowest methanol diffusion coefficient of the modified membrane is 4.56 × 10−8 cm2 s−1, which is only about 1/50th of that of Nafion117. In addition, the membranes exhibit feasible proton conductivity and higher selectivity than Nafion117. These results indicate that the chitosan‐modified core–shell SiO2‐acidic polymer multiple crosslinked membranes have potential applications in direct‐methanol fuel cells. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48494. [ABSTRACT FROM AUTHOR]

ABSTRACT Determining the differences in flower hydraulic traits and structural resource allocation among closely related species adapted to low mean annual precipitation (MAP) can provide insight into plant adaptation to arid environments. Here, we measured the maximum flower hydraulic conductance (Kmax‐flower), water potential at induction 50% loss of Kmax‐flower (P50‐flower), flower pressure–volume parameters, dry mass of individual flowers and structural components (vexillum, wings, keels, stamens and sepals) of six Caragana species growing in regions ranging from 110 to 1400 mm MAP. Compared with species from high‐MAP environments, those from low‐MAP environments presented lower Kmax‐flower, more negative P50‐flower, osmotic potential at full turgor (πo) and turgor loss points (πtlp), and a greater bulk modulus of elasticity (ε). Consequently, a negative correlation between Kmax‐flower (hydraulic efficiency) and P50‐flower (hydraulic safety) was observed across Caragana species. Furthermore, the dry masses of individual flowers and structural components (vexillum, wings, keels, stamens and sepals) were greater in the species from the low‐MAP environment than in those from the high‐MAP environment. These findings suggest that greater flower hydraulic safety and drought tolerance combined with greater structural resource allocation promote drought adaptation in Caragana species to low‐MAP environments. [ABSTRACT FROM AUTHOR]