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Bisphenol A (BPA) is considered a contaminant of emerging concern and interferes with the normal activities of living organisms. The toxicity of BPA is evident in animals, while there have been relatively few studies focused on the effects of this chemical on plants especially how submerged macrophytes respond to low BPA concentrations is still unclear. In the present study, effects of low BPA loading (targeting at 0.01, 0.1 and 1 mg/L) on the growth and reproductive traits of the dioecious annual submerged macrophyte Vallisneria natans were assessed through a five-month experiments. The results showed that BPA inhibited the elongation of V. natans leaves but resulted in an increase in leaf number and ramet number under the highest BPA loading treatment (targeting at 1 mg/L). At the highest BPA loading treatment, female individuals of V. natans allocated less mass for ramet than male ones, showing a clear sexual dimorphism. No significant differences in reproductive traits and total biomass of the V. natans were found between different BPA loading treatments and the control, indicating that BPA did not induce direct toxic effects on the growth and reproductive traits of V. natans. In summary, V. natans tolerated low BPA concentrations by trade-offs between ramet (leaf) number and leaf elongation and maintained a stable reproduction output probably based on sexual dimorphism.

Background We aimed to evaluate the tolerability and efficacy of linezolid in children for treating suspected and diagnosed Gram-positive bacterial infections. Methods A systematic literature search was conducted up to April 23, 2021, using linezolid and its synonyms as search terms. Two reviewers independently identified and extracted relevant randomized controlled trials and prospective cohort studies. The extracted studies were included in a single-rate meta-analysis of adverse events and clinical outcomes using random-effects models. Results A total of 1082 articles were identified, and nine studies involving 758 children were included in the meta-analysis. The overall proportion of adverse events was 8.91% [95% confidence interval (CI) = 1.64%–36.52%], with diarrhea (2.24%), vomiting (2.05%), and rash (1.72%) being the most common. The incidences of thrombocytopenia and anemia were 0.68% and 0.16%, respectively. Some specific adverse events, including rash and gastrointestinal events, were more frequent in the oral administration subgroup. In terms of efficacy, the overall proportion of clinical improvement was 88.80% (95% CI = 81.31%–93.52%). Children with a history of specific bacteriological diagnosis or concomitant antibiotic therapy had a 1.13-fold higher clinical improvement than children without such histories. The proportion of microbial eradication was 92.68% (95% CI = 84.66%–96.68%). The proportion of all-cause mortality was 0.16% (95% CI = 0.00%–7.75%). Conclusions Linezolid was well-tolerated in pediatric patients and was associated with a low frequency of adverse events, such as anemia, thrombocytopenia, and neutropenia. Moreover, linezolid was effective in children with diagnosed and suspected Gram-positive infections.

TetR family transcriptional regulators (TFRs) are widespread in actinomycetes, which exhibit diverse regulatory modes in antibiotic biosynthesis. Nitrogen regulators play vital roles in modulation of primary and secondary metabolism. However, crosstalk between TFR and nitrogen regulator has rarely been reported in actinomycetes. Herein, we demonstrated that a novel TFR, SACE_4839, was negatively correlated with erythromycin yield in Saccharopolyspora erythraea A226. SACE_4839 indirectly suppressed erythromycin synthetic gene eryAI and resistance gene ermE and directly inhibited its adjacent gene SACE_4838 encoding a homologue of nitrogen metabolite repression (NMR) regulator NmrA (herein named NmrR). The SACE_4839-binding sites within SACE_4839-nmrR intergenic region were identified. NmrR positively controlled erythromycin biosynthesis by indirectly stimulating eryAI and ermE and directly repressing SACE_4839. NmrR was found to affect growth viability under the nitrogen source supply. Furthermore, NmrR directly repressed glutamine and glutamate utilization-related genes SACE_1623, SACE_5070 and SACE_5979 but activated nitrate utilization-associated genes SACE_1163, SACE_4070 and SACE_4912 as well as nitrite utilization-associated genes SACE_1476 and SACE_4514. This is the first reported NmrA homolog for modulating antibiotic biosynthesis and nitrogen metabolism in actinomycetes. Moreover, combinatorial engineering of SACE_4839 and nmrR in the high-yield S. erythraea WB resulted in a 68.8% increase in erythromycin A production. This investigation deepens the understanding of complicated regulatory network for erythromycin biosynthesis. KEY POINTS: • SACE_4839 and NmrR had opposite contributions to erythromycin biosynthesis. • NmrR was first identified as a homolog of another nitrogen regulator NmrA. • Cross regulation between SACE_4839 and NmrR was revealed.

In both plants and animals, nucleotide-binding leucine-rich repeat (NLR) immune receptors play critical roles in pathogen recognition and activation of innate immunity. In plants, NLRs recognise pathogen-derived effector proteins and initiate effector-triggered immunity (ETI). However, the molecular mechanisms that link NLR-mediated effector recognition and downstream signalling are not fully understood. By exploiting the well-characterised tomato Prf/Pto NLR resistance complex, we identified the 14-3-3 proteins TFT1 and TFT3 as interacting partners of both the NLR complex and the protein kinase MAPKKKα. Moreover, we identified the helper NRC proteins (NLR-required for cell death) as integral components of the Prf /Pto NLR recognition complex. Notably our studies revealed that TFTs and NRCs interact with distinct modules of the NLR complex and, following effector recognition, dissociate facilitating downstream signalling. Thus, our data provide a mechanistic link between activation of immune receptors and initiation of downstream signalling cascades.

Landslides : journal of the International Consortium on Landslides (2022). doi:10.1007/s10346-021-01817-z, Published by Springer, Berlin ; Heidelberg

Background Liuwei Dihuang Pill (LP) was verified to alleviate postmenopausal osteoporosis (PMOP) development. Nevertheless, the major constituent of LP and the related network pharmacology study remain unexplored. Methods Protein–protein interaction was established to identify the downstream target of LP in PMOP, and the related signaling pathway was investigated by bioinformatics analysis. MC3T3-E1 cells were added to ferric ammonium citrate (FAC) to mimic osteoporosis in vitro. The osteoblasts were identified by Alizarin red staining. Western blot was applied to evaluate protein levels. In addition, Cell Counting Kit-8 (CCK8) assay was applied to assess cell viability, and cell apoptosis was assessed by flow cytometry. Results Quercetin was the major constituent of LP. In addition, quercetin significantly reversed FAC-induced inhibition of osteogenic differentiation in MC3T3-E1 cells. In addition, quercetin notably abolished the FAC-induced upregulation of Bax, Caspase-3, FOS, JUN, TGFB1 and PPARD. In contrast, Bcl-2, p-mTOR/mTOR, p-AKT/AKT and p-PI3K/PI3K levels in MC3T3-E1 cells were reduced by FAC, which was restored by quercetin. Meanwhile, FAC notably inhibited the viability of MC3T3-E1 cells via inducing apoptosis, but this impact was abolished by quercetin. Furthermore, quercetin could reverse pcDNA3.1-FOS-mediated growth of FAC-treated osteoblasts by mediating PI3K/AKT/mTOR signaling. Conclusion Quercetin alleviated the progression of PMOP via activation of PI3K/AKT/mTOR signaling. Hence, this study would shed novel insights into discovering new methods against PMOP.

Switch/sucrose-nonfermenting (SWI/SNF) complexes play a key role in chromatin remodeling. Recent studies have found that SMARCC2, as the core subunit of the fundamental module of the complex, plays a key role in its early assembly. In this study, we found a unique function of SMARCC2 in inhibiting the progression of glioblastoma by targeting the DKK1 signaling axis. Low expression of SMARCC2 is found in malignant glioblastoma (GBM) compared with low-grade gliomas. SMARCC2 knockout promoted the proliferation of glioblastoma cells, while its overexpression showed the opposite effect. Mechanistically, SMARCC2 negatively regulates transcription by dynamically regulating the chromatin structure and closing the promoter region of the target gene DKK1, which can be bound by the transcription factor EGR1. DKK1 knockdown significantly reduced the proliferation of glioblastoma cell lines by inhibiting the PI3K–AKT pathway. We also studied the functions of the SWIRM and SANT domains of SMARCC2 and found that the SWIRM domain plays a more important role in the complete chromatin remodeling function of SMARCC2. In addition, in vivo studies confirmed that overexpression of SMARCC2 could significantly inhibit the size of intracranial gliomas in situ in nude mice. Overall, this study shows that SMARCC2, as a tumor suppressor, inhibits the proliferation of glioblastoma by targeting the transcription of the oncogene DKK1 through chromatin remodeling, indicating that SMARCC2 is a potentially attractive therapeutic target in glioblastoma.

The prediction of antidepressant response is critical for psychiatrists to select the initial antidepressant drug for patients with major depressive disorders (MDD). The implicated brain networks supporting emotion regulation (ER) are critical in the pathophysiology of MDD and the prediction of antidepressant response. Therefore, the primary aim of the current study was to identify the neuroimaging biomarkers for the prediction of remission in patients with MDD based on the resting-state functional connectivity (rsFC) of the ER networks. A total of 81 unmedicated adult MDD patients were investigated and they underwent resting-state functional magnetic resonance imagining (fMRI) scans. The patients were treated with escitalopram for 12 weeks. The 17-item Hamilton depression rating scale was used for assessing remission. The 36 seed regions from predefined ER networks were selected and the rsFC matrix was caculated for each participant. The support vector machine algorithm was employed to construct prediction model, which separated the patients with remission from those with non-remission. And leave-one-out cross-validation and the area under the curve (AUC) of the receiver operating characteristic were used for evaluating the performance of the model. The accuracy of the prediction model was 82.08% (sensitivity = 71.43%, specificity = 89.74%, AUC = 0.86). The rsFC between the left medial superior frontal gyrus and the right inferior frontal gyrus as well as the precuneus were the features with the highest discrimination ability in predicting remission from escitalopram among the MDD patients. Results from our study demonstrated that rsFC of the ER brain networks are potential predictors for the response of antidepressant drugs. The trial name: appropriate technology study of MDD diagnosis and treatment based on objective indicators and measurement. URL: http://www.chictr.org.cn/showproj.aspx?proj=21377. Registration number: ChiCTR-OOC-17012566.

We assessed the value of computed tomography (CT) and automated Alberta Stroke Program Early CT Score (ASPECTS) with net water uptake (NWU) to predict stroke onset time. Two-hundred forty stroke patients with anterior circulation large-vessel occlusion were included. CT-ASPECTS-NWU values were calculated by comparing the mean Hounsfield units of affected ASPECTS regions with unaffected contralateral regions. The correlation between ASPECTS-NWU and stroke onset to CT time was assessed. ASPECTS-NWU predictive values were calculated to identify a stroke onset to CT time of within 4.5/6 h. A correlation existed between stroke onset to CT time and ASPECTS-NWU (r = 0.65, p

The Lrp and MarR families are two groups of transcriptional regulators widely distributed among prokaryotes. However, the hierarchical-regulatory relationship between the Lrp family and the MarR family remains unknown. Our previous study found that an Lrp (SACE_Lrp) from Saccharopolyspora erythraea indirectly repressed the biosynthesis of erythromycin. In this study, we characterized a novel MarR family protein (SACE_6745) from S. erythraea, which is controlled by SACE_Lrp and plays a direct regulatory role in erythromycin biosynthesis and export. SACE_Lrp directly regulated the expression of marR by specifically binding a precise site OM (5'-CTCCGGGAACCATT-3'). Gene disruption of marR increased the production of erythromycin by 45% in S. erythraea A226. We found that MarR has direct DNA-binding activity for the promoter regions of the erythromycin biosynthetic genes, as well as an ABC exporter SACE_2701-2702 which was genetically proved to be responsible for erythromycin efflux. Disruption of SACE_Lrp in industrial S. erythraea WB was an efficient strategy to enhance erythromycin production. Herein, we jointly engineered SACE_Lrp and its target MarR by deleting marR in WBΔSACE_Lrp, resulting in 20% increase in erythromycin yield in mutant WBΔLrpΔmarR compared to WBΔSACE_Lrp, and 39% to WB. Overall, our findings provide new insights into the hierarchical-regulatory relationship of Lrp and MarR proteins and new avenues for coordinating antibiotic biosynthesis and export by joint engineering regulators in actinomycetes. KEY POINTS: • The hierarchical-regulatory relationship between SACE_Lrp and MarR was identified. • MarR directly controlled the expression of erythromycin biosynthesis and export genes. • Joint engineering of SACE_Lrp-MarR regulatory element enhanced erythromycin production.

Additive manufacturing (AM) is a relatively novel method to fabricate 3D objects by adding layer-upon-layer materials. As one of the most anticipated techniques in recent years, AM already made advances in design, production, and supply chain process of the manufacturing industry. AM is a digital manufacturing technology in which a massive amount of data is generated during the process. Accordingly, obtaining useful information from these data to improve current AM technology becomes a challenge. Meanwhile, Big Data research provides an ideal solution for dealing with the massive data obtained from AM processes. Besides the contributions in the AM research and production, Big Data analysis methods can also be used to help designers and engineers by collecting valuable information from clients and customers. From a business perspective, the manufacturing sector will benefit from the established Big Data sharing platform to promote and popularize new products. On the other hand, customers will obtain desired commodities with the help of a new-type 3D printing service system. The goal of this article is to summarize the contributions from the existing literature in the AM and Big Data field and prospect how Big Data methods can offer a better future for AM technology. It also introduces recent developments in AM technology combined with the internet of things (IoT), cloud, and cybersecurity. Future directions in AM and Big Data, which include AM data unification, completed AM data-sharing platform, and smart AM production process is pointed out as well.

The effects of modifiers on the anti-wetting and anti-icing property of the prepared rough aluminum surface were investigated. The rough aluminum substrates were obtained through electrochemical oxidization with 15 wt% sulfuric acid solution as the electrolyte at the constant current of 4 mA for 3 h. And then they were modified with octadecanoic acid (C18), polyethylene (PE), polystyrene (PS), polyethylene glycol (PEG) and hexamethylenetetramine (HMTA), respectively, whose surface free energies were 27.6, 31.0, 33.0, 61.6 and 70.0 mN/m, respectively. The contact angles (CA) were 154.6°, 128.4°, 127.6°, 5.0° and 0.0°, respectively, and the ice adhesion pressures were 15.9, 36.3, 55.9, 155.3 and 216.1 kPa, respectively. The ice adhesion strengths decrease along with the increasing anti-wetting property of aluminum surfaces and the decreasing of the surface energy of modifiers. These provide some new insights when designing the aluminum surface with anti-icing properties in some special applications.

Exogenous antioxidant materials mimicking endogenous antioxidant systems are commonly used for the treatment of oxidative stress-induced injuries. Thus, artificial enzymes have emerged as promising candidates for balancing and treating the dysregulation of redox homeostasis in vivo. Herein, a one-pot hydrothermal strategy for the facile preparation of MoSe2-polyvinylpyrrolidone (PVP) nanoparticles (NPs) is reported. The synthesized NPs were biodegradable due to their exposure to oxygen and exhibited high stability. Moreover, they effectively mimicked various naturally occurring enzymes (including catalase, superoxide dismutase, peroxidase, and glutathione peroxidase) and scavenged free radicals, such as 3-ethylbenzothiazoline-6-sulfonic acid, ·OH, ·O2−, and 1,1-diphenyl-2-picrylhydrazyl radical. Further apoptosis detection studies revealed that MoSe2-PVP NPs significantly increased the cell survival probability in H2O2 in a concentration-dependent manner. The cytoprotective effect of MoSe2-PVP NPs was explored for an animal model of acute pancreatitis, which confirmed its remarkable therapeutic efficacy. Owing to the biodegradable and biocompatible nature of MoSe2-PVP NPs, the findings of this work can stimulate the development of other artificial nanoenzymes for antioxidant therapies. Graphical Abstract

Loneliness is an unpleasant experience of lacking desired interpersonal relationships. Abundant evidence has clarified the negative outcomes of loneliness, such as anxiety, even suicidal behaviors. However, relatively few is known about the internal buffering elements for loneliness, especially in adolescents. The current research aimed to investigate the relationship between self-compassion and adolescents’ loneliness, as well as the mediating roles of fear of negative evaluation and social anxiety in this relationship. A total of 871 Chinese adolescents completed a set of questionnaires, including the measures of loneliness, self-compassion, social anxiety and the fear of negative evaluation. We tested the proposed serial mediation model and the results suggested that self-compassion was negatively associated with loneliness, and social anxiety served as a mediator in the relationship. Besides, we found that the fear of negative evaluation and social anxiety serially mediated the negative association. Specifically, self-compassionate adolescents reported less fear of negative evaluation, which resulted in decreased social anxiety symptoms. In turn, the decreased social anxiety was linked to reduced feelings of loneliness. The present study sheds lights on the mediating effects of fear of negative evaluation and social anxiety in the relationship between self-compassion and loneliness. The theoretical and practical implications, as well as the limitations of the present study, are discussed.

In this study, the halloysite nanotubes was characterized and the adsorption of Th(IV) and U(VI) on halloysite nanotubes was investigated as a function of contact time, adsorbent dosage, pH, ionic strength, initial U(VI) concentration and temperature using batch method. Meanwhile, the adsorption mechanism of uranium and thorium on halloysite nanotubes was discussed. The microscopic results displayed that halloysite nanotubes was tubular morphology and highly porous and high specific surface area of ca. 55.65 m2/g. The adsorption results showed that the adsorption of U(VI) and Th(IV) on halloysite nanotubes followed pseudo-second-order kinetic model. The strong pH dependent adsorption of U(VI) and Th(IV) displayed their strong surface complexation with the surface of halloysite nanotubes. The adsorption of Th(IV) and U(VI) increased with elevating temperature and was an endothermic and spontaneous process. The adsorption isotherms of Th(IV) and U(VI) can be better described by Freundlich and D–R model. The effect of ionic strength on the adsorption of thorium on halloysite nanotubes was much greater than that on uranium(almost unaffected), which suggested the adsorption of Th(IV) on halloysite nanotubes was most probably based on the formation of inner-sphere complexes, while that of U(VI) was based on the formation of outer-sphere complex on the edge surfaces. Th(IV) and U(VI) adsorption–desorption isotherm on halloysite nanotubes indicated adsorption process was irreversible. The selectivity order of adsorption by the halloysite nanotubes was Th(IV) > U(VI). The higher adsorption efficiency of the halloysite nanotubes for Th(IV) could be utilized for selective separation of Th(IV) from U(VI) aqueous with pH 4.1–4.3. The novel and environmentally friendly adsorption material is feasible to extract thorium from waste aqueous solution.

The combination of photothermal therapy (PTT) and photodynamic therapy (PDT) has attracted attention due to its enhanced tumor therapy effect. This study proposes a novel nanoenzyme-based theranostic nanoplatform, IrO2@MSN@PDA-BSA(Ce6), for the combined PTT and PDT of tumors. IrO2 was prepared by a simple hydrolysis method and coated with a thin layer of mesoporous silica (MSN) to facilitate the physical adsorption of Chlorin e6 (Ce6). The PDA coating and IrO2 NPs of the nanoplatform demonstrated an improved photothermal conversion efficiency of 29.8% under NIR irradiation. Further, the Ce6 loading imparts materials with the ability to produce reactive oxygen species (ROS) under 660 nm NIR laser irradiation. It was also proved that the IrO2 NPs could catalyze the hydrogen peroxide (H2O2) in the tumor microenvironment (TME) to generate endogenous oxygen (O2), thereby enhancing the efficiency of PDT. The in vitro and in vivo experiments indicated that the nanocomposite was highly biocompatible and could produce a satisfactory tumor therapeutic effect. Thus, the findings of the present study demonstrate the viability of using theranostic nanoenzymes for translational medicine.

Stiff-stilbene derivatives have been widely explored as molecular rotors, molecular force probes and optical switches with excellent performance. However, their function as fluorophores is poorly understood. In the present work, we design three stiff-stilbene derivatives and study their photophysical properties. These compounds exhibit very weak emission in solution but significantly enhanced monomer emission in viscous solvent, bright excimer emission in aggregates and at solid state. Detailed spectroscopic studies, single crystal structural analysis, powder X-ray diffraction (XRD) as well as effects of substituents have been carefully examined. They provide direct evidence that intermolecular interactions and molecular packing, which can restrict bond vibration and rotation, are responsible for the bright aggregation-induced emission.

Connections among multi-energy systems become increasingly closer with the extensive application of various energy equipment such as gas-fired power plants and electricity-driven gas compressor. Therefore, the integrated energy system has attracted much attention. This paper establishes a gas-electricity joint operation model, proposes a system evaluation index based on the energy quality character after considering the grade difference of the energy loss of the subsystem, and finds an optimal scheduling method for integrated energy systems. Besides, according to the typical load characteristics of commercial and residential users, the optimal scheduling analysis is applied to the integrated energy system composed of an IEEE 39 nodes power system and a 10 nodes natural gas system. The results prove the feasibility and effectiveness of the proposed method.

Owing to the hypoxia status of the tumor, the reactive oxygen species (ROS) production during photodynamic therapy (PDT) of the tumor is less efficient. Herein, a facile method which involves the synthesis of Mg-Mn-Al layered double hydroxides (LDH) clay with MoS2 doping in the surface and anionic layer space of LDH was presented, to integrate the photo-thermal effect of MoS2 and imaging and catalytic functions of Mg-Mn-Al LDH. The designed LDH-MoS2 (LMM) clay composite was further surface-coated with bovine serum albumin (BSA) to maintain the colloidal stability of LMM in physiological environment. A photosensitizer, chlorin e6 (Ce6), was absorbed at the surface and anionic layer space of LMM@BSA. In the LMM formulation, the magnetic resonance imaging of Mg-Mn-Al LDH was enhanced thanks to the reduced and acid microenvironment of the tumor. Notably, the ROS production and PDT efficiency of Ce6 were significantly improved, because LMM@BSA could catalyze the decomposing of the overexpressed H2O2 in tumors to produce oxygen. The biocompatible LMM@BSA that played the synergism with tumor microenvironment is a promising candidate for the effective treatment of cancer.

To assess the psychological effects of the novel coronavirus disease (COVID-19) on medical staff and the general public. During the outbreak of COVID-19, an internet-based questionnaire included The Self-rating Depression Scale (SDS), Perceived Stress Scale (PSS-10), and Impact of Event Scale-Revised (IES-R) was used to assess the impact of the pandemic situation on the mental health of medical staff and general population in Wuhan and its surrounding areas. Among the 1493 questionnaires completed, 827 (55.39%) of these were men, and 422 (28.27%) of these were medical personnel. The results suggest that the outbreak of COVID-19 has affected individuals significantly, the degree of which is related to age, sex, occupation and mental illness. There was a significant difference in PSS-10 and IES-R scores between the medical staff and the general population. The medical staff showed higher PSS-10 scores (16.813 ± 4.87) and IES-R scores (22.40 ± 12.12) compared to members of the general population PSS-10 (14.80 ± 5.60) and IES-R scores (17.89 ± 13.08). However, there was no statistically significant difference between the SDS scores of medical staff (44.52 ± 12.36) and the general public (43.08 ± 11.42). In terms of the need for psychological assistance, 50.97% of interviewees responded that they needed psychological counseling, of which medical staff accounted for 65.87% and non-medical staff accounted for 45.10%. During the ongoing COVID-19 outbreak, great attention should be paid to the mental health of the population, especially medical staff, and measures such as psychological intervention should be actively carried out for reducing the psychosocial effects.

The histogram of oriented gradients (HOG) is widely used for image description and has proven to be very effective. In some practical applications that lack an assumption of the object’s orientation, rotation-invariant detection is of vital significance. To address this problem, this paper presents a new visual feature, Sector-ring HOG (SRHOG), which is obtained by improving the gradient binning and spatial binning based on HOG. The new feature can convert planar image rotations into cyclic shifts of the final descriptor and thereby facilitate rotated object detection. After modifying boosted random ferns in SRHOG feature domain, we further propose two strategies for rotation-invariant object detection: one depends completely on the new feature’s characteristic, and the other introduces an orientation estimation step. The former is more suitable to ‘finding objects’ and the latter can provide the higher orientation estimation accuracy. Both the use of supervised learning and working in the gradient space make our approaches effective and robust. We show these properties by thorough testing on the public Freestyle Motocross dataset and our dataset for victim detection in post-disaster rescue efforts.

A high-efficiency, low-cost and environment-friendly 2-acrylamide-2-methyl propane sulfonic acid (AMPS)-modified hazelnut-shell-based adsorbent(AHS) was synthesized and used to adsorb Cu2+, Pb2+, methylene blue(MB) and malachite green(MG) from aqueous solutions. The AHS was characterized by means of SEM, BET, FTIR and XPS. Different experimental parameters were evaluated in batch adsorption experiments to determine the optimal adsorption conditions. Adsorption kinetics shows that the adsorption rate is well represented by the pseudo- second-order rate model, and the Langmuir model gives the best fit adsorption isotherm. The Langmuir maximum adsorption capacities were found to be 21.14 mg/g for Cu2+, 32.74 mg/g for Pb2+, 68.03 mg/g for MB and 263.16 mg/g for MG, respectively, while the adsorption capacities could be maintained above 90% even after ten adsorp-tion-desorption cycles. The experimental results show that AHS could be applied to treat both industrial and munici-pal wastewaters.

Background Erythromycin A (Er-A) produced by the actinomycete Saccharopolyspora erythraea is an important antibiotic extensively used in human medicine. Dissecting of transcriptional regulators and their target genes associated with erythromycin biosynthesis is crucial to obtain erythromycin overproducer strains through engineering of relevant regulatory elements in S. erythraea. Results Here, we identified a TetR family transcriptional regulator (TFR), SACE_5754, negatively controlling erythromycin production. SACE_5754 indirectly repressed the transcription of ery cluster and cannot regulate itself and its adjacent gene SACE_5753. RNA-seq coupled with EMSAs and qRT-PCR was performed to identify the targets of SACE_5754, and confirmed that transcription of SACE_0388 (encoding a pyruvate, water diknase), SACE_3599 (encoding an antibiotic resistance macrolide glycosyltransferase) and SACE_6149 (encoding a FAD-binding monooxygenase) were directly repressed by SACE_5754. A consensus palindromic sequence TYMAGG-n2/n4/n11-KKTKRA (Y: C/T, M: A/C, K: T/G, R: A/G) was proved to be essential for SACE_5754 binding using DNase I footprinting and EMSAs. During the three target genes of SACE_5754, SACE_0388 and SACE_6149 exhibited the positive effect on erythromycin production. Overexpression of either SACE_0388 or SACE_6149 in ∆SACE_5754 further increased the Er-A production. By engineering the industrial strain S. erythraea WB with deletion of SACE_5754 combined with overexpression of either SACE_0388 or SACE_6149, Er-A production in WB∆SACE_5754/pIB139–0388 and WB∆SACE_5754/pIB139–6149 was successively increased by 42 and 30% compared to WB. Co-overexpression of SACE_0388 and SACE_6149 in WB∆SACE_5754 resulted in enhanced Er-A production by 64% relative to WB. In a 5-L fermenter, WB∆SACE_5754/pIB139–0388-6149 produced 4998 mg/L Er-A, a 48% increase over WB. Conclusion We have identified a TFR, SACE_5754, as a negative regulator of erythromycin biosynthesis, and engineering of SACE_5754 and its target genes, SACE_0388 and SACE_6149, resulted in enhanced erythromycin production in both wild-type and industrial S. erythraea strains. The strategy demonstrated here may be valuable to facilitate the manipulation of transcriptional regulators and their targets for production improvement of antibiotics in industrial actinomycetes. Electronic supplementary material The online version of this article (10.1186/s13036-018-0135-2) contains supplementary material, which is available to authorized users.

Visceral leishmaniasis (VL), a vector-borne disease caused by protozoan flagellates of the genus Leishmania, is transmitted by sand flies. After malaria, VL is the second-largest parasitic killer, responsible for an estimated 500,000 infections and 51,000 deaths annually worldwide. Mathematical models proposed for VL have included the impact of dogs versus wild canids in disease dissemination and models developed to assist in control approaches. However, quantitative conditions that are required to control or eradicate VL transmission are not provided and there are no mathematical methods proposed to quantitatively calculate optimal control strategies for VL transmission. The research objective of this work was to model VL disease transmission system (specifically Zoonotic VL), perform bifurcation analysis to discuss control conditions, and calculate optimal control strategies. Three time-dependent control strategies involving dog populations, sand fly population, and humans are mainly discussed. Another strategy sometimes used in attempts to control zoonotic VL transmission, dog culling, is also evaluated in this paper.

Validamycin A (VAL-A) is a C7N aminocyclitol antibiotic produced by Streptomyces hygroscopicus var. jinggangensis 5008, which has been widely used as antifungal agent against rice sheath blight disease. VAL-A biosynthesis has been proven to be affected by γ-butyrolactone and temperature. Herein, we showed that GlnR, a global regulator in nitrogen metabolism, is specifically associated with valK-valA intergenic promoter region by DNA-affinity chromatography and MS-based protein identification. Subsequent EMSA and DNase I footprinting assays revealed two GlnR binding sites in this promoter region. Targeted disruption of glnR in S. hygroscopicus 5008 led to a significant increase in the transcription of VAL-A structural genes, albeit the VAL-A production was reduced by 80 % and the sporulation of the mutant was impaired. Compared with the wild-type 5008, site-specific mutagenesis of GlnR binding site I enhanced VAL-A production by 2.5-fold, whereas the mutation of GlnR binding site II resulted in a 50 % reduction of VAL-A yield. Moreover, tandem mutation of site I in the site II mutant led to a 66 % increase of VAL-A production. The result suggested that GlnR not only serves as an inhibitor by binding site I but also as an activator by binding site II for VAL-A biosynthesis. Furthermore, overexpression of glnR in the site I mutant JG45 improved VAL-A production for 41 % compared with the control strain containing the vector. Therefore, the obtained data illustrate a novel regulatory feature of the global regulator GlnR. GlnR is firstly proved to act simultaneously as an activator and a repressor in validamycin biosynthesis by binding to different loci within a promoter region of the gene cluster.

BldD (SACE_2077), a key developmental regulator in actinomycetes, is the first identified transcriptional factor in Saccharopolyspora erythraea positively regulating erythromycin production and morphological differentiation. Although the BldD of S. erythraea binds to the promoters of erythromycin biosynthetic genes, the interaction affinities are relatively low, implying the existence of its other target genes in S. erythraea. Through the genomic systematic evolution of ligands by exponential enrichment (SELEX) method that we herein improved, four DNA sequences of S. erythraea A226, corresponding to the promoter regions of SACE_0306 (beta-galactosidase), SACE_0811 (50S ribosomal protein L25), SACE_3410 (fumarylacetoacetate hydrolase), and SACE_6014 (aldehyde dehydrogenase), were captured with all three BldD concentrations of 0.5, 1, and 2 μM, while the previously identified intergenic regions of eryBIV-eryAI and ermE-eryCI plus the promoter region of SACE_7115, the amfC homolog for aerial mycelium formation, could be captured only when the BldD's concentration reached 2 μM. Electrophoretic mobility shift assay (EMSA) analysis indicated that BldD specifically bound to above seven DNA sequences, and quantitative real-time PCR (qRT-PCR) assay showed that the transcriptional levels of the abovementioned target genes decreased when bldD was disrupted in A226. Furthermore, SACE_7115 and SACE_0306 in A226 were individually inactivated, showing that SACE_7115 was predominantly involved in aerial mycelium formation, while SACE_0306 mainly controlled erythromycin production. This study provides valuable information for better understanding of the pleiotropic regulator BldD in S. erythraea, and the improved method may be useful for uncovering regulatory networks of other transcriptional factors.

Robots should ideally perceive objects using human-like multi-modal sensing such as vision, tactile feedback, smell, and hearing. However, the features presentations are different for each modal sensor. Moreover, the extracted feature methods for each modal are not the same. Some modal features such as vision, which presents a spatial property, are static while features such as tactile feedback, which presents temporal pattern, are dynamic. It is difficult to fuse these data at the feature level for robot perception. In this study, we propose a framework for the fusion of visual and tactile modal features, which includes the extraction of features, feature vector normalization and generation based on bag-of-system (BoS), and coding by robust multi-modal joint sparse representation (RM-JSR) and classification, thereby enabling robot perception to solve the problem of diverse modal data fusion at the feature level. Finally, comparative experiments are carried out to demonstrate the performance of this framework.

In order to enhance the production of validamycin A (VAL-A), a widely used agricultural antibiotic, a temperature shift strategy was developed in the fermentation of Streptomyces hygroscopicus 5008. VAL-A production and the transcriptional levels of its structural genes were enhanced in the optimal temperature shift condition. The addition of diphenyleneiodonium [DPI, reactive oxygen species (ROS) inhibitor] inhibited intracellular ROS level and VAL-A production, which indicated that ROS signal might contribute to the enhancement of VAL-A production in the temperature shift process. The transcriptional levels of stress response sigma factors SigmaB and SigmaH as well as global regulator PhoRP were enhanced, which suggested that these regulators might participate in the signal pathway. This study developed a useful strategy for VAL-A production. It will help to further understand the regulation mechanism of ROS on VAL-A synthesis. The involvement of ROS in this process will encourage researchers to develop new ROS induction strategies to enhance VAL-A production.

The structure of bacterial cellulose (BC) produced by Acetobacter xylinum NUST4 (A.xylinum NUST4) under static (SBC) and shake culture condition (ABC) was studied by means of transmission electron microscopic (TEM), X-ray diffraction (XRD) and Fourier transform-infrared spectrum (FT-IR). It was revealed that BC is I crystal cellulose and the proportion of cellulose Iα exceeds 80% and BC diameter is 10–80 nm. Mechanical properties and water absorption capacity were also determined. These properties could result from crystalline and nanometer structure of BC.

The present status and development trends of nano-composite coatings were briefly introduced. The nano-SiO2 was dispersed into crylic acid resin by ultrasonic wave and high-energy ball milling, the influence of nano-SiO2 on shielding property of coatings was investigated. Relation between particle size distribution of original nano-SiO2 and its dispersal in water and alcohol after treatment were analyzed, respectively. The ultraviolet permeation rate of coatings filled with nano-SiO2 was detected by ultraviolet spectral photometer. And the particle size distribution of coatings was examined by TEM. The results show that particle size distribution is comparative convergence and smaller one order of magnitude after dispersal treatment. The size of most nano-SiO2 in coatings is smaller than 100 nm, which indicates that the amount of nano-SiO2 in the resin is 20% (solid content of resin), the permeation rate of ultraviolet of composite coatings decreases to 20%. The research of its excellent ultraviolet shielding property mechanism indicates minor size and high surface energy of nano-SiO2 can produce different absorption, reflection and scatter actions to different wavelengths.

Let {Y, Yi, −∞ < i < ∞} be a doubly infinite sequence of identically distributed and asymptotically linear negative quadrant dependence random variables, {ai, −∞ < i < ∞} an absolutely summable sequence of real numbers. We are inspired by Wang et al. (Econometric Theory 18:119–139, 2002) and Salvadori (Stoch Environ Res Risk Assess 17:116–140, 2003). And Salvadori (Stoch Environ Res Risk Assess 17:116–140, 2003) have obtained Linear combinations of order statistics to estimate the quantiles of generalized pareto and extreme values distributions. In this paper, we prove the complete convergence of \({\left\{ {{\sum\nolimits_{k = 1}^n {{\sum\nolimits_{i = - \infty }^\infty {a_{{i + k}} Y_{i} /n^{{1/t}} } }} },n \geq 1} \right\}}\) under some suitable conditions. The results obtained improve and generalize the results of Li et al. (1992) and Zhang (1996). The results obtained extend those for negative associated sequences and ρ*-mixing sequences.

Background Saccharopolyspora erythraea was extensively utilized for the industrial-scale production of erythromycin A (Er-A), a macrolide antibiotic commonly used in human medicine. Yet, S. erythraea lacks regulatory genes in the erythromycin biosynthetic gene (ery) cluster, hampering efforts to enhance Er-A production via the engineering of regulatory genes. Results By the chromosome gene inactivation technique based on homologous recombination with linearized DNA fragments, we have inactivated a number of candidate TetR family transcriptional regulators (TFRs) and identified one TFR (SACE_7301) positively controlling erythromycin biosynthesis in S. erythraea A226. qRT-PCR and EMSA analyses demonstrated that SACE_7301 activated the transcription of erythromycin biosynthetic gene eryAI and the resistance gene ermE by interacting with their promoter regions with low affinities, similar to BldD (SACE_2077) previously identified to regulate erythromycin biosynthesis and morphological differentiation. Therefore, we designed a strategy for overexpressing SACE_7301 with 1 to 3 extra copies under the control of PermE* in A226. Following up-regulated transcriptional expression of SACE_7301, eryAI and ermE, the SACE_7301-overexpressed strains all increased Er-A production over A226 proportional to the number of copies. Likewise, when SACE_7301 was overexpressed in an industrial S. erythraea WB strain, Er-A yields of the mutants WB/7301, WB/2×7301 and WB/3×7301 were respectively increased by 17%, 29% and 42% relative to that of WB. In a 5 L fermentor, Er-A accumulation increased to 4,230 mg/L with the highest-yield strain WB/3×7301, an approximately 27% production improvement over WB (3,322 mg/L). Conclusions We have identified and characterized a TFR, SACE_7301, in S. erythraea that positively regulated erythromycin biosynthesis, and overexpression of SACE_7301 in wild-type and industrial S. erythraea strains enhanced Er-A yields. This study markedly improves our understanding of the unusual regulatory mechanism of erythromycin biosynthesis, and provides a novel strategy towards Er-A overproduction by engineering transcriptional regulators of S. erythraea. Electronic supplementary material The online version of this article (doi:10.1186/s12934-014-0158-4) contains supplementary material, which is available to authorized users.