Targeting of G-protein coupled receptor 40 alleviates airway hyperresponsiveness through RhoA/ROCK1 signaling pathway in obese asthmatic mice.

Obesity increases the severity of airway hyperresponsiveness (AHR) in individuals with asthma, but the mechanism is not well elucidated. G-protein coupled receptor 40 (GPR40) has been found to induce airway smooth muscle contraction after activated by long-chain fatty acids (LC-FFAs), suggesting a close correlation between GPR40 and AHR in obese. In this study, C57BL/6 mice were fed a high-fat diet (HFD) to induce obesity with or without ovalbumin (OVA) sensitization, the regulatory effects of GPR40 on AHR, inflammatory cells infiltration, and the expression of Th1/Th2 cytokines were evaluated by using a small-molecule antagonist of GPR40, DC260126. We found that the free fatty acids (FFAs) level and GPR40 expression were greatly elevated in the pulmonary tissues of obese asthmatic mice. DC260126 greatly reduced methacholine-induced AHR, ameliorated pulmonary pathological changes and decreased inflammatory cell infiltration in the airways in obese asthma. In addition, DC260126 could down-regulate the levels of Th2 cytokines (IL-4, IL-5, and IL-13) and pro-inflammatory cytokines (IL-1ß, TNF-α), but elevated Th1 cytokine (IFN-γ) expression. In vitro, DC260126 could remarkedly reduce oleic acid (OA)-induced cell proliferation and migration in HASM cells. Mechanistically, the effects that DC260126 alleviated obese asthma was correlated with the down-regulation of GTP-RhoA and Rho-associated coiled-coil-forming protein kinase 1 (ROCK1). Herein, we proved that targeting of GPR40 with its antagonist helped to mitigate multiple parameters of obese asthma effectively.

Facile Synthesis and Multiple Application of Ultralong-Afterglow Room Temperature Phosphorescence Aggregate Carbon Dots from Simple Raw Materials.

Owing to the ultralong afterglow, room temperature decay phosphorescence nanomaterials have aroused enough attention. In the work, by simple one-pot solid-state thermal decomposition reaction, aggregate carbon dots (CDs) was prepared from trimesic and boric acid. Based on the intermolecular hydrogen bonds and intramolecular π-π stacking weak interaction from precursors, CDs was encapsulated in boron oxide matrix and formed aggregation. The aggregate state of CDs facilitated the triplet excited states (Tn), which could induce the room temperature decay phosphorescence properties. By careful investigation, under different excitation wavelengths at 254 and 365 nm, the aggregate CDs showed > 15 s and > 3 s room temperature phosphorescence emission in the naked eye, which was associated with 1516.12 ms and 718.62 ms lifetime respectively. And the aggregate CDs exhibited widespread application in encoding encryption, optical anti-counterfeiting and fingerprint identification etc. The interesting aggregate CDs revealed unexpected ultralong-afterglow room temperature decay phosphorescence properties and the work opened a window for constructing ultralong-afterglow room temperature decay phosphorescence aggregate CDs nanomaterials.

Whole-plant microbiome profiling reveals a novel geminivirus associated with soybean stay-green disease.

Microbiota colonize every accessible plant tissue and play fundamental roles in plant growth and health. Soybean stay-green syndrome (SGS), a condition that causes delayed leaf senescence (stay-green), flat pods and abnormal seeds of soybean, has become the most serious disease of soybean in China. However, the direct cause of SGS is highly debated, and little is known about how SGS affect soybean microbiome dynamics, particularly the seed microbiome. We studied the bacterial, fungal, and viral communities associated with different soybean tissues with and without SGS using a multi-omics approach, and investigated the possible pathogenic agents associated with SGS and how SGS affects the assembly and functions of plant-associated microbiomes. We obtained a comprehensive view of the composition, function, loads, diversity, and dynamics of soybean microbiomes in the rhizosphere, root, stem, leaf, pod, and seed compartments, and discovered that soybean SGS was associated with dramatically increased microbial loads and dysbiosis of the bacterial microbiota in seeds. Furthermore, we identified a novel geminivirus that was strongly associated with soybean SGS, regardless of plant cultivar, sampling location, or harvest year. This whole-plant microbiome profiling of soybean provides the first demonstration of geminivirus infection associated with microbiota dysbiosis, which might represent a general microbiological symptom of plant diseases.

Real-Time Visual Biofeedback via Wearable Ultrasound Imaging Can Enhance the Muscle Contraction Training Outcome of Young Adults.

ABSTRACT: Huang, Z-H, Ma, CZ-H, Wang, L-K, Wang, X-Y, Fu, S-N, and Zheng, Y-P. Real-time visual biofeedback via wearable ultrasound imaging can enhance the muscle contraction training outcome of young adults. J Strength Cond Res 36(4): 941-947, 2022-Real-time ultrasound imaging (RUSI) can serve as visual biofeedback to train deep muscle contraction in clinical rehabilitative settings. However, its effectiveness in resistance training in sports/fitness fields remains unexplored. This article introduced a newly developed wearable RUSI system that provided visual biofeedback of muscle thickening and movement and reported its effectiveness in improving the training outcomes of muscle thickness change (%) during dynamic contraction. Twenty-five healthy young men participated and performed pec fly exercise both with and without RUSI biofeedback. Statistical analysis was conducted to examine the reliability of the measurements and the immediate effects of (a) RUSI biofeedback of muscle contraction and (b) training intensity (50 vs. 80% of 1-repetition maximum [1RM]) on the pectoralis major (PMaj) thickness change measured by ultrasound images. In addition to significantly high inter-contraction reliability (ICC3,1 > 0.97), we observed significantly increased PMaj thickness change for both training intensities upon receiving biofeedback in subjects, compared with without biofeedback (p < 0.001). We also observed significantly larger PMaj thickness change at 80% of 1RM compared with 50% of 1RM (p = 0.023). The provision of visual biofeedback using RUSI significantly enlarged the magnitude of PMaj thickness change during pec fly exercises, potentially indicating that RUSI biofeedback could improve the ability of targeted muscle contraction of PMaj in healthy young adults. To our knowledge, this study has pioneered in applying RUSI as a form of biofeedback during weight training and observed positive effectiveness. Future iterations of the technique will benefit more subject groups, such as athletes and patients with neuromuscular disorders.

An epidemiological investigation of food allergy among children aged 3 to 6 in an urban area of Wenzhou, China.

BACKGROUND: The prevalence of food allergy (FA) has increased worldwide. In China, the prevalence of FA in infants and school-aged children is well known, but the prevalence in preschool children is unknown. METHODS: A total of 4151 preschool children aged 3 to 6 years in urban Wenzhou, China, were recruited for this cross-sectional study. Their parents completed a preliminary screening questionnaire, and a detailed FA questionnaire was given to parents whose children had suspected FA according to the preliminary screening. According to the results of the detailed FA questionnaires, some children underwent a skin prick test (SPT) and specific IgE (sIgE) measurement. Children with abnormal SPT and/or sIgE results who did not meet the diagnostic criteria and those with negative SPT and sIgE results whose histories strongly supported FA underwent an oral food challenge (OFC). RESULTS: Of the 4151 children's parents who completed the surveys, 534 (12.86%) indicated a positive medical history of FA. Among the 40 children who underwent an OFC, 24 were positive. According to SPT and sIgE measurements, 11 children were diagnosed with FA. The prevalence of FA was at least 0.84%; children who dropped out during the study were considered FA-negative. Among the 35 children with FA, the most common allergic manifestation was skin symptoms. The most common allergic foods were egg, fish and shrimp. CONCLUSIONS: The parent-reported rate of FA in preschool children in urban Wenzhou was 12.86%. The prevalence of FA was at least 0.84%. Among all cases, the most common allergic food was eggs, and the most common allergic manifestation was skin symptoms. TRIAL REGISTRATION: NCT03974555, registered on 30 May 2019 (www.clinicaltrials.gov).

The allosteric modulation effects of doxycycline, minocycline, and their derivatives on the neuropeptide receptor PAC1-R.

Class B G-protein coupled receptors (GPCR) PAC1-R is a neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP)-preferring receptor that mediates the effective neuroprotective activity. Based on our previous data showing that doxycycline and minocycline work as the positive allosteric modulator (PAM) of PAC1-R, we used computer molecular docking and isothermal titration calorimetry assay to further determine the bindings of doxycycline/minocycline's derivatives including tetracycline/tigecycline with the N-terminal extracellular domain of PAC1-R (PAC1-EC1). Then the cAMP assay combined with the PAC1-R natural agonist PACAP27 was used to confirm the possible PAM roles of the small-molecule antibiotics. The results showed that tetracycline/tigecycline had significant lower affinity to PAC1-EC1 than doxycycline/minocycline, which was consistent with their non-positive allosteric modulation activity on PAC1-R. Furthermore, by comparing the key residues contributing to the PAM binding with the predicted allosteric site in PAC1-EC1, we characterized four motifs contributing to PAM binding in PAC1-EC1. The site-directed mutation results showed that ASN60 played the most important role in the PAM binding of the small-molecule antibiotics, while ASP116 played a sensitive marginal role in the PAM binding. These results not only help to explain the clinical and experimental neuroprotective effects of doxycycline/minocycline, but also help to characterize the PAM binding site in PAC1-EC1, which will promote the screening and characterization of novel small-molecule PAMs targeting PAC1-EC1 with drug development potency in nerve system disease.

Towards Wearable Comprehensive Capture and Analysis of Skeletal Muscle Activity during Human Locomotion.

BACKGROUND: Motion capture and analyzing systems are essential for understanding locomotion. However, the existing devices are too cumbersome and can be used indoors only. A newly-developed wearable motion capture and measurement system with multiple sensors and ultrasound imaging was introduced in this study. METHODS: In ten healthy participants, the changes in muscle area and activity of gastrocnemius, plantarflexion and dorsiflexion of right leg during walking were evaluated by the developed system and the Vicon system. The existence of significant changes in a gait cycle, comparison of the ankle kinetic data captured by the developed system and the Vicon system, and test-retest reliability (evaluated by the intraclass correlation coefficient, ICC) in each channel's data captured by the developed system were examined. RESULTS: Moderate to good test-retest reliability of various channels of the developed system (0.512 ≤ ICC ≤ 0.988, p < 0.05), significantly high correlation between the developed system and Vicon system in ankle joint angles (0.638R ≤ 0.707, p < 0.05), and significant changes in muscle activity of gastrocnemius during a gait cycle (p < 0.05) were found. CONCLUSION: A newly developed wearable motion capture and measurement system with ultrasound imaging that can accurately capture the motion of one leg was evaluated in this study, which paves the way towards real-time comprehensive evaluation of muscles and joint motions during different activities in both indoor and outdoor environments.

Provincial analysis and zoning of atmospheric pollution in China from the atmospheric transmission and the trade transfer perspective.

The "Joint Prevention and Control of Regional Air Pollution in China" has been put forward to solve serious regional air pollution. However, there is no geographical division covering the whole country that could reveal the similarities and differences among regions to support implementing this policy. This paper applied an air quality model and a multiregional input-output model to analyze the impacts and patterns of atmospheric transmission and trade transfer of regional air pollution, then compared the differences among typical provinces in the northern, central and southern regions. The social network analysis method was used to analyze the interacting pattern of regional atmospheric transmission and trade transfer, and 31 provinces in mainland China were divided into 5 clusters to reveal the interprovincial relationship of atmospheric transmission; then, the 31 provinces were divided into 3 clusters to reveal the interprovincial relationship of trade transfer. Based on these results, the provincial geographical division of "Nine Atmospheric Environmental Transmission Zones" covering mainland China was carried out. In addition, the key regions linking atmospheric transmission and trade transfer were also found. For example, Inner Mongolia is a typical key linkage region. From an atmospheric transmission perspective, it is linked to the northeast area. However, from a trade transfer perspective, it has a close relationship with the southern provinces. The linkage among provinces provides support for the interregional interaction mechanism of air pollution and the formulation of "Joint Prevention and Control of Regional Air Pollution in China".

Divergent Synthesis of Chiral Covalent Organic Frameworks.

Featuring the simultaneous generation of a library of compounds from a certain intermediate, divergent synthesis has found increasing applications in the construction of natural products and potential medicines. Inspired by this approach, presented herein is a general strategy to introduce functionality, in a divergent manner, into covalent organic frameworks (COFs). This modular protocol includes two stages of covalent assembly, through which functional COFs can be constructed by a three-step transformation of a key platform molecule, such as 4,7-dibromo-2-chloro-1H-benzo[d]imidazole (DBCBI). Constructed herein are four types of chiral COFs (CCOFs) from DBCBI by nucleophilic substitution, Suzuki coupling, and imine formation. The unique array of eight isoframework CCOFs allowed investigation of their catalytic performance and structure-activity relationship in an asymmetric amination reaction.

Retraction Note to: Overexpression of a cotton annexin gene, GhAnn1, enhances drought and salt stress tolerance in transgenic cotton.

The authors are retracting this article because irregularities were involved in the reuse of stomatal images in Figure 9.

Benzoxazole-Linked Ultrastable Covalent Organic Frameworks for Photocatalysis.

The structural uniqueness of covalent organic frameworks (COFs) has brought these new materials great potential for advanced applications. One of the key aspects yet to be developed is how to improve the robustness of covalently linked reticular frameworks. In order to make the best use of π-conjugated structures, we develop herein a "killing two birds with one stone" strategy and construct a series of ultrastable benzoxazole-based COFs (denoted as LZU-190, LZU-191, and LZU-192) as metal-free photocatalysts. Benefiting from the formation of benzoxazole rings through reversible/irreversible cascade reactions, the synthesized COFs exhibit permanent stability in the presence of strong acid (9 M HCl), strong base (9 M NaOH), and sunlight. Meanwhile, reticulation of the benzoxazole moiety into the π-conjugated COF frameworks decreases the optical band gap and therefore increases the capability for visible-light absorption. As a result, the excellent photoactivity and unprecedented recyclability of LZU-190 (for at least 20 catalytic runs, each with a product yield of 99%) have been illustrated in the visible-light-driven oxidative hydroxylation of arylboronic acids to phenols. This contribution represents the first report on the photocatalytic application of benzoxazole-based structures, which not only sheds new light on the exploration of robust organophotocatalysts from small molecules to extended frameworks but also offers in-depth understanding of the structure-activity relationship toward practical applications of COF materials.

Cornea Full-field Displacement and Strain Measurement in Vivo Using Three-dimensional Digital Image Correlation.

SIGNIFICANCE: Corneal biomechanics are becoming increasingly important for clinical evaluation and diagnosis, such as in refractive surgery, glaucoma, and keratoconus. We developed and used a new technique to measure the full-field displacement and strain of the cornea under elevated intraocular pressure in vivo. PURPOSE: In this study, we propose a three-dimensional digital image correlation method for the determination of corneal biomechanical properties. METHODS: Corneal deformation change on the rabbit eyeball was investigated under different inflation conditions with intraocular pressure levels of 2.3, 3.3, 5.3, and 6.9 kPa in vivo. RESULTS: The proposed method was able to measure the displacement of the corneal surface and to construct real-time full-field three-dimensional deformation vector fields and strain mapping. The results show that the strain distribution is not uniform on the corneal surface at each intraocular pressure level. Compression strains, rather than extensile strains, are dominant at the corneal apex region. CONCLUSIONS: This technique has the potential to be used as an assistive tool for the determination of corneal biomechanical properties in ophthalmologic investigations.

A Cotton Annexin Affects Fiber Elongation and Secondary Cell Wall Biosynthesis Associated with Ca2+ Influx, ROS Homeostasis, and Actin Filament Reorganization.

Annexins play pivotal roles in a variety of cellular processes as well as in fiber development; however, the functional mechanisms of their activities are unclear. Here, an annexin gene that is preferentially expressed in fibers, GhFAnnxA, was found to be significantly associated with various cotton (Gossypium hirsutum) fiber traits. Transgenic analysis demonstrated that GhFAnnxA affected cotton fiber elongation and was involved in secondary cell wall (SCW) biosynthesis. Functional studies demonstrated that GhFAnnxA may act as a Ca(2+) conductance regulator and that reactive oxygen species (ROS) produced by Rbohs in a Ca(2+)-dependent manner may determine fiber elongation caused by elevated intracellular turgor and cell wall loosening. However, excessive hydrogen peroxide (H2O2) inhibited cotton fiber elongation in vitro. We speculate that a positive feedback loop involving ROS and Ca(2+) is regulated by GhCDPK1 and regulates fiber cell elongation. Furthermore, the convergence of actin filaments is altered by their interaction with GhFAnnxA, and this also may contribute to fiber elongation. Moreover, GhFAnnxA may affect SCW biosynthesis through changes in cell wall components caused by an increase in H2O2 levels. These results not only provide new insights into the signaling pathways of GhFAnnxA in fiber development but also clarify the role of ROS in fiber development.

The role of Melatonin receptor MTNR1A in the action of Melatonin on bovine granulosa cells.

Granulosa cells (GCs) play an important role in ovarian follicle growth, development, and follicular atresia. In the present study, we investigated the effects of Melatonin on bovine GCs, and asked if MTNR1A was involved in their response to this indole hormone. Our results indicated that Melatonin inhibited GC apoptosis by up-regulating the expression of BCL2, BCL-XL, GPX4, and SOD1, and down-regulating the expression of BAX, CASP3, and TP53. Moreover, Melatonin modulated bovine GC function by decreasing the expression of INHA, INHBB, FSHR, and TGFBR3, and the abundance of Inhibin ß and Activin B, while increasing the expression of LHR, INHBA, and secretion of progesterone by GCs. In contrast, knockdown of MTNR1A significantly increased the expression of BAX, CASP3, TP53, INHA, FSHR, and TGFBR3, as well as Inhibin ß abundance, while decreasing the expression of BCL2, GPX4, SOD1, and LHR, and production of progesterone and estradiol; no effect was observed on the expression of BCL-XL, INHBA, or INHBB. These results suggest that Melatonin and MTNR1A play an important role in modulating bovine GC function by regulating cellular progression, apoptosis, hormones secretion, and reproduction-related genes. Furthermore, altered expression of MTNR1A could affect how bovine GCs respond to Melatonin.

Interactive effects of glutamine and gamma-aminobutyric acid on growth performance and skeletal muscle amino acid metabolism of 22-42-day-old broilers exposed to hot environment.

The present experiment was conducted to investigate the interactive effects between dietary glutamine (Gln, 0 and 5 g/kg) and gamma-aminobutyric acid (GABA, 0 and 100 mg/kg) on growth performance and amino acid (AA) metabolism of broilers under hot environment. A total of 360 22-day-old Arbor Acres male chickens were randomly assigned to five treatment groups under thermoneutral chamber (PC, 23 °C) and cyclic heat stress (HS, 30-34 °C cycling) conditions. Compared with the PC group, cyclic HS decreased (P < 0.05) daily weight gain (DWG), daily feed consumption (DFC), the concentrations of Gln, glutamate (Glu), and GABA, and the activities of glutaminase and glutamic acid decarboxylase (GAD) in breast muscle at 28, 35, and 42 days, while it increased (P < 0.05) the activities of glutamine synthetase (GS) and gamma-aminobutyric acid transaminase (GABA-T) at 28, 35, and 42 days. Dietary Gln and GABA improved (P < 0.05) DWG and DFC of broilers under cyclic HS during 28-42 days. In breast muscle, the Gln supplementation increased (P < 0.05) the concentrations of Gln (28, 35, and 42 days), Glu (28, 35, and 42 days), and GABA (42 days) and the activities of glutaminase (28, 35, and 42 days) and GAD (28, 35, and 42 days) but decreased (P < 0.05) GS activities at 28, 35, and 42 days and GABA-T activities at 28 days. The addition of GABA increased (P < 0.05) the concentrations of Gln and Glu and activities of glutaminase and GAD, while it decreased (P < 0.05) GABA-T activities at 28, 35, and 42 days. Significant interactions (P < 0.05) between Gln and GABA were found on breast skeletal muscle Gln concentrations, glutaminase activities, GS activities at 28 and 35 days, and DWG, GABA concentrations, and GABA-T activities at 28, 35, and 42 days in broilers under cyclic HS. In conclusion, the present results indicated that the interactions of exogenous Gln and GABA could offer a potential nutritional strategy to prevent HS-related depression in skeletal muscle Gln and GABA metabolism of broilers.

Overexpression of a cotton annexin gene, GhAnn1, enhances drought and salt stress tolerance in transgenic cotton.

Plant annexins are members of a diverse, multigene protein family that has been associated with a variety of cellular processes and responses to abiotic stresses. GhAnn1, which encodes a putative annexin protein, was isolated from a cotton (Gossypium hirsutum L. acc 7235) cDNA library. Tissue-specific expression showed that GhAnn1 is expressed at differential levels in all tissues examined and strongly induced by various phytohormones and abiotic stress. In vivo and in vitro subcellular localization suggested that GhAnn1 is located in the plasma membrane. In response to drought and salt stress, transgenic cotton plants overexpressing GhAnn1 showed significantly higher germination rates, longer roots, and more vigorous growth than wild-type plants. In addition, plants overexpressing GhAnn1 had higher total chlorophyll content, lower lipid peroxidation levels, increased peroxidase activities, and higher levels of proline and soluble sugars, all of which contributed to increased salt and drought stress tolerance. However, transgenic cotton plants in which the expression of GhAnn1 was suppressed showed the opposite results compared to the overexpressing plants. These findings demonstrated that GhAnn1 plays an important role in the abiotic stress response, and that overexpression of GhAnn1 in transgenic cotton improves salt and drought tolerance.

Assessment of ocular biomechanics using dynamic ultra high-speed Scheimpflug imaging in keratoconic and normal eyes.

PURPOSE: To introduce several new ocular biomechanical parameters for comparison between keratoconic and normal eyes using an analysis method based on corneal dynamic deformation video recorded by corneal visualization Scheimpflug technology (Corvis ST; Oculus Optikgeräte GmbH, Wetzlar, Germany). METHODS: This comparative study comprised 52 keratoconic eyes of 43 patients with keratoconus and 52 normal eyes of 52 controls. An analysis method (PolyU [Labview 2009; National Instrument, Austin, TX]) was developed to introduce several new ocular biomechanical parameters and to compare the difference between keratoconic and normal eyes. The repeatability of the new parameters measurement was evaluated and compared with the Corvis ST measurement. Receiver operating characteristic curves were used to establish a cutoff value for the new biomechanical parameters. RESULTS: Intraclass correlation coefficients of the deformation amplitude, peak distance, corneal concave radius of curvature, maximum deformation area, maximum corneal inward velocity and outward velocity (Vin, max and Vout, max) were high in both the keratoconic and normal eyes (all intraclass correlation coefficients > 0.75). The measurement agreement of the PolyU analysis method and Corvis ST was good. Most of the biomechanical parameters of patients with keratoconus were significantly different from those of the controls. In the receiver operating characteristic analysis, the Vin, max was the best predictive parameter with an area under the curve of 0.79. CONCLUSIONS: The corneal deformation video recorded by the Corvis ST provides useful information for the study of ocular biomechanics. Most of the new ocular biomechanical parameters were significantly different between keratoconic and normal eyes. Further research is needed to develop more comprehensive clinical applications with these new ocular biomechanical parameters.

Responses of Populus trichocarpa galactinol synthase genes to abiotic stresses.

Galactinol synthase (GolS; EC 2.4.1.123) is a member of the glycosyltransferase eight family that catalyzes the first step in the biosynthesis pathway of the raffinose family of oligosaccharides (RFOs). The accumulation of RFOs in response to abiotic stress indicates a role for RFOs in stress adaptation. To obtain information on the roles of RFOs in abiotic stress adaptation in trees, we investigated the expression patterns of nine Populus trichocarpa GolS (PtrGolS) genes with special reference to stress responses. PtrGolS genes were differentially expressed in different organs, and the expressions of PtrGolS4 and PtrGolS6 were relatively high in all tested organs. The expression levels of all PtrGolS genes, except PtrGolS9, changed in response to abiotic stress in gene- and stress-type-specific manners. Moreover, short- and long-term stress treatments revealed that induction of PtrGolS by salt stress is obvious only in the early period of treatment (within 24 h), whereas water-deficit stress treatments continued to upregulate PtrGolS gene expression after two days of treatment, in addition to induction within 24 h of treatment. Consistent with these expression patterns, the galactinol content in leaves increased after four days of drought stress, but not under salt stress. Our findings suggest divergent roles for PtrGolS genes in abiotic stress responses in poplars.

Overexpression of PtSOS2 Enhances Salt Tolerance in Transgenic Poplars.

Protein kinases are major signal transduction factors that have a central role in mediating acclimation to environmental changes in eukaryotic organisms. In this study, we cloned and identified three salt overly sensitive 2 (SOS2) genes in the woody plant Populus trichocarpa, designated as PtSOS2.1, PtSOS2.2, and PtSOS2.3, which were transformed into hybrid poplar clone T89 (Populus tremula× Populus tremuloides Michx clone T89) mediated by Agrobacterium tumefaciens. Southern and northern blot analyses verified that the three genes integrated into the plant genome, and were expressed at a stable transcription level. Meanwhile, overexpression of all three PtSOS2 genes did not retard the growth of plants under normal conditions. Instead, it promoted growth in both agar-medium and soil conditions in response to salinity stress. Under salt stress, overexpression of PtSOS2.1, PtSOS2.2, and PtSOS2.3 increased the concentrations of proline and photosynthetic pigments, and the relative water content (RWC), and the activity of antioxidant enzymes, and decreased the malondialdehyde (MDA) concentrations in transgenic lines compared to the control. These results suggest that overexpression of PtSOS2 plays a significant role in improving the salt tolerance of poplars, reducing the damage to membrane structures, and enhancing osmotic adjustment and antioxidative enzyme regulation under salt stress.

The thin-layer drying characteristics of sewage sludge by the appropriate foaming pretreatment.

As dewatered sludge is highly viscous and sticky, the combination of foaming pretreatment and drying process seems to be an alternative method to improve the drying performance of dewatered sludge. In this study, CaO addition followed by mechanical whipping was employed for foaming the dewatered sludge. It was found that the foams were stable and the diameters of bubbles mainly ranged from 0.1 to 0.3 mm. The drying experiments were carried out in a drying oven in the convective mode. The results indicated that foamed sludge at 0.70 g/cm(3) had the best drying performance at each level of temperature, which could save 35-45% drying time to reach 20% moisture content compared with the non-foamed sludge. The drying rate of foamed sludge at 0.70 g/cm(3) was improved with the increasing of drying temperature. The impact of sample thickness on drying rate was not obvious when the sample thickness increased from 2 to 8 mm. Different mathematical models were used for the simulation of foamed sludge drying curves. The Wang and Singh model represented the drying characteristics better than other models with coefficient of determination values over 0.99.