With the air quality ranking of China’s Ministry of Ecology and Environment as a case, this paper examines whether the public ranking could stimulate the ranked cities to improve performance. The ...results show that the horizontal ranking, i.e., the relative position among the cities, significantly stimulates the cities to improve air quality. The stimulating effect is significant for all the three type of cities, i.e., cities with good, medium and poor air quality, and is the strongest for the cities with good air quality. However, the stimulating effect for air quality improvement is not enough to alter the air quality comparison among the cities. Compared to other cities, if a city is ranked relatively low in the last year, the air quality in the current year is still relatively poor. The inertia is particularly significant for the cities with poor air quality. The vertical ranking, i.e., if the rank of a city progresses or retrogresses, does not affect the air quality and air quality change of the city. Overall, public ranking is argued to stimulate performance improvement by seducing the competition among local governments, although the actual effect is still subject to the perception of local governments and their capacity to respond to the ranking.
Insect life processes and reproductive behaviors are significantly affected by extremely high temperatures. This study focused on Tuta absoluta, which poses a severe threat to tomato cultivars. The ...effects of intense heat stress on the growth, development, oviposition, and longevity of T. absoluta were investigated. This investigation encompassed various developmental stages, including eggs, pupae, and adults. This study revealed that egg hatching and pupa emergence rates were significantly reduced at a temperature of 44 °C maintained for 6 h. The longevity of adults that emerged after the egg and pupal stages were exposed to 44 °C for 6 h was significantly reduced compared to the control. Notably, there was no significant variation in adult fecundity after egg-stage exposure to high temperatures. However, all treatments exhibited significantly reduced fecundity compared to the control after exposure to high temperatures during the pupal stage. Adult survival rates after exposure to 40 °C and 44 °C for 3 h were 74.29% and 22.40%, respectively, dramatically less than that of the control, which was 100%. However, no significant differences were noted in terms of longevity and egg production. These results offer a better understanding of the complex interactions between extreme temperatures and the life history traits of T. absoluta, thereby offering valuable insights for implementing management strategies to alleviate its impact on tomato crops in response to climate change.
Dulaglutide (glucagon like peptide-1/IgG-Fc fusion protein, GLP-1-Fc) is a long lasting GLP-1 agonist, which consists of two arms of GLP-1 moieties fused to IgG Fc fragment. Dulaglutide is a safe and ...effective medication for type 2 diabetes. In an attempt to develop a biosimilar version of dulaglutide, we found that up to 75% of GLP-1-Fc displayed
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-terminal truncations in one or both GLP-1 arms. We proposed that the
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-terminal heterogeneity was caused by mis-cleavage of signal peptide and solved this problem through signal peptide optimization. Murine immunoglobulin kappa light chain signal peptide (KASP) significantly improves GLP-1-Fc
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-terminal integrity and homogeneity. 92.8–95.7% of GLP-1-Fc molecules directed by KASP contain intact
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-terminus. The productivity of GLP-1-Fc could reach 2.2 g/L in shaking flask fed batch culture. KASP is an optimal signal peptide for GLP-1-Fc expression in Chinese hamster ovary (CHO) cells.
A total of 99 endophytic fungal isolates were obtained from the roots of Glycyrrhiza inflata, which was a traditional medicinal plant mainly distributed in Xinjiang, China. Twenty-two distinct ...isolates were selected for further taxonomical identification by morphological traits and internal transcribed spacer (ITS) rRNA gene sequence analysis. Eleven genera were identified, among which Aspergillus, Alternaria and Fusarium were dominant. The crude extracts of 22 distinct identified fungi were successively evaluated for their antifungal activities on three rice fungal pathogens using the method of hyphal radial growth rate. Among them, the crude extract of Alternaria an-gustiovoidea Glinf007 showed the significantly mycelial growth inhibitory activity. The results demonstrated that G. inflata contained a diversity of culturable endophytic fungi, which could produce natural antimicrobial compounds that might be of great value to the agriculture and pharmaceutical industries.
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.
The bacterial communities in rhizosphere soil interact with the roots of plants. This interaction is beneficial for both the bacteria and the plants, which makes it very important to identify the ...structure of these bacterial communities for plant growth and development. However, the composition characteristics of bacterial communities in rhizosphere soil of 2-year and 5-year Haloxylon ammodendron have not been clearly defined. The purpose of this study was to identify the diverse composition of 2-year and 5-year Haloxylon ammodendron in Turpan, Xinjiang. Thus, rhizosphere soil bacteria were analyzed by isolating, purifying, and identifying the species through high-throughput sequencing technology. The bacterial strains in the rhizosphere soil of Haloxylon ammodendron were isolated with the dilution coating method, resulting in 37 isolated strains. The selective media were used to screen the growth-promoting characteristics of the rhizosphere soil isolates of Haloxylon ammodendron. The results of high-throughput amplification sequencing showed that the rhizosphere bacteria in the 2-year rhizosphere soil belonged to 45 phyla, 109 classes, 288 orders, 451 families, 826 genera, and 404 species, and those in the 5-year rhizosphere soil belonged to 56 phyla, 148 classes, 369 orders, 601 families, 1062 genera, and 671 species. Among them, Firmicutes, Proteobacteria, Actinobacteriota, Bacteroidota, Crenarchaeota, and so on are the dominant bacteria. There were 12206 and 14,053 OTUs in the 2-year-old and 5-year-old rhizosphere soil bacteria, respectively, and 3329 OTUs in the 2-year- and 5-year-old rhizosphere soil, accounting for 16.98% of the total number of OTUs. The results showed that three strains, sg16, sg21, and ss4, had the highest inorganic phosphorus solubility index (1.58). The isolated strain did not have the ability to dissolve organophosphorus and potassium, while the screened strain sg16 had the ability to fix nitrogen. Two strains with a good iron-bearing capacity, Sg9F and Sg1, were screened, among which Sg9F had the highest D/d value and Sg9F had the strongest iron-bearing capacity. The results showed that 37 strains of rhizosphere soil bacteria belonged to six genera. They are Bacillus, Corynebacterium, Phyllobacterium, Lysinibacillus, Sinorhizobium meliloti, and Streptomyces levis. Among them are sg21 (Bacillus sp.), sg1 (Bacillus sp.), sg9F (Streptomyces levis), sg16 (Phyllobacterium phragmitis), and ss4 (Sinorhizobium meliloti). This study provides a particular research basis for the influence of Haloxylon ammodendron rhizosphere bacteria on soil nutrient release and depicts a solution for improving the yield and quality of cistanche deserticola indirectly through isolating, screening, and identifying rhizosphere soil bacteria, including screening strains with growth-promoting functions and analyzing the population structure of rhizosphere bacteria in 2- and 5-year soil in combination with high-throughput sequencing technology.
VPAC1 is class B G protein-coupled receptors (GPCR) shared by pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP). The first cysteine (Cys37) in the ...N-terminal extracellular domain of mature VPAC1 is a free Cys not involved in the formation of conserved intramolecular disulfide bonds. In order to investigate the biological role of this Cys37 in VPAC1, the wild-type VPAC1 and Cys37/Ala mutant (VPAC1-C37/A) were expressed stably as fusion proteins with enhanced yellow fluorescent protein (EYFP) respectively in Chinese hamster ovary (CHO) cells. Both VPAC1-EYFP and VPAC1-C37/A-EYFP trafficked to the plasma membrane normally, and CHO cells expressing VPAC1-EYFP displayed higher anti-apoptotic activity against camptothecin (CPT) induced apoptosis than the cells expressing VPAC1-C37/A-EYFP, while VPAC1-C37/A-CHO cells showed higher proliferative activity than VPAC1-CHO cells. Confocal microscopic analysis, western blotting and fluorescence quantification assay showed VPAC1-EYFP displayed significant nuclear translocation while VPAC1-C37/A-EYFP did not transfer into nucleus under the stimulation of VIP (0.1 nM). Acyl-biotin exchange assay and click chemistry-based palmitoylation assay confirmed for the first time the palmitoylation of Cys37, which has been predicted by bioinformatics analysis. And the palmitoylation inhibitor 2-bromopalmitate significantly inhibited the nuclear translocation of VPAC1-EYFP and its anti-apoptotic activity synchronously. These results indicated the palmitoylation of the Cys37 in the N-terminal extracellular domain of VPAC1 mediates the nuclear translocation of VPAC1 contributing to its anti-apoptotic activity. These findings reveal for the first time the lipidation-mediating nuclear translocation of VPAC1 produces a novel anti-apoptotic signal pathway, which may help to promote new drug development strategy targeting VPAC1.
Pituitary adenylate cyclase‐activating polypeptide (PACAP) receptor 1 (PAC1‐R) is the neuropeptide PACAP‐preferring receptor‐mediating neuroprotective activity. In order to clarify the biological ...mechanism of its expression, we cloned the 2,526 bp promoter fragment from −2,500 to +26 of the transcription initiation site of human ADCYAP1R1 gene and constructed the novel promotor reporter system named pYr‐PromDetect‐PAC1p. It was found in SH‐SY5Y cells low concentration (<10 nM) of hydrogen peroxide (H2O2) significantly promoted the activity of PAC1‐R promoter in dose‐dependent way, which was significantly inhibited by the transcription factor specificity protein 1 (SP1) inhibitor mithramycin A and was further confirmed in the deletion mutation of the predicted SP1 binding sites. Moreover, higher concentration of H2O2 (>10 nM) inhibited the activity of PAC1‐R in dose‐dependent way. The hormesis effect of H2O2 on PAC1‐R promoter would help to further clarify the physiological effect of low‐dose reactive oxygen on nervous system.
Practical applications
PAC1‐R mediates well‐known neuroprotective, neurotrophic, and neurogenesis effects, which is an important drug target for neurodegenerative diseases. The hormesis effects of oxidative stress on PAC1‐R expression not only help to explain the hormesis effects of oxidative stress on nerve system, but also offer a novel strategy to increase the expression of PAC1‐R for the nerve protection or nerve generation. For example, taking advantage of low degree of oxidative stress to increases the expression of PAC1‐R might help prevent subsequent surgical serious injury on the nervous system. The activation of PAC1‐R promoter by low concentration of H2O2 would help to further clarify the physiological effect of low‐dose reactive oxygen on nervous system.
As-extruded Mg–5Sn–1Zn–xAl alloys(x=1, 3, and 5) were fabricated by hot extrusion. The experimental results revealed that the yield strength of alloys initially decreased and then increased with the ...increase of Al content. These changes were mainly attributed to the difference in crystallographic texture and volume fractions of second phases. The ultimate tensile strength, yield strength, and elongation of the alloys were greater than 310 MPa, 227 MPa, and 11%, respectively. The strain hardening ability of the alloys was also discussed.
Mg-5Zn-1Mn (wt%) alloy sheets with good strength-ductility balance were successfully fabricated by high strain-rate rolling (HSRR) in a wide temperature range from 250°C to 400°C. The microstructural ...evolution, dynamic precipitation characteristics and mechanical properties of the as-rolled sheets were investigated. The results show that the dynamic precipitation plays a key role in the as-rolled microstructural evolution and the mechanical properties. The uniform and dispersive precipitates with high spatial distribution density mainly nucleated on the α-Mn particles and along the dislocations during the HSRR. A typical bimodal microstructure can be obtained even at the high rolling temperature (400°C) by the HSRR process due to the dynamic precipitates strongly pinning the boundaries of the dynamic recrystallization (DRX) grains or subgrains. The sheet fabricated by HSRR at 300°C exhibits high strength and excellent ductility, with the ultimate tensile strength (UTS), yield tensile strength (YS) and elongation (EL) to failure of 359MPa, 258MPa and 20.1%, respectively. The superior mechanical properties can be attributed to the ultrafine DRX grains featured with the bimodal microstructure and the precipitates with high density.
High density of nano-sized precipitates dynamically nucleated on the Mn particles and the high density of dislocations induced by the high strain rate rolling (HSRR). The precipitates can effectively suppress the growth of DRX grains by pinning the boundaries of the DRX grains or subgrains. The superior combination of strength and ductility for the sheet is contributed to the grain refinement and precipitation strengthening. Display omitted
•Mg-5Zn-1Mn alloy sheets with high strength and good ductility were fabricated by high strain-rate rolling.•The rolled sheets exhibit optimal mechanical properties with ultimate tensile strength of 359MPa and elongation of 20.1%.•The enhanced strength and ductility benefit from ultrafine XRD grains and high density of nano-precipitates.•The nano-sized Mg-Zn phases were dynamically precipitated by heterogeneous nucleation on dislocations and α-Mn particles.
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