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The genus Streptomyces comprises the most important chitin decomposers in soil and revealing their chitinolytic machinery is beneficial for the conversion of chitinous wastes. Streptomyces sp. SCUT-3, a chitin-hydrolyzing and a robust feather-degrading bacterium, was isolated previously. The potential chitin-degrading enzymes produced by SCUT-3 were analyzed in the present study. Among these enzymes, three chitinases were successfully expressed in Pichia pastoris at comparatively high yields of 4.8 U/mL (SsExoChi18A), 11.2 U/mL (SsExoChi18B), and 17.8 U/mL (SsEndoChi19). Conserved motifs and constructive 3D structures of these three exo- and endochitinases were also analyzed. These chitinases hydrolyzed colloidal chitin to chitin oligomers. SsExoChi18A showed apparent synergic effects with SsEndoChi19 in colloidal chitin and shrimp shell hydrolysis, with an improvement of 29.3 % and 124.9 %, respectively. Compared with SsExoChi18B and SsEndoChi19, SsExoChi18A exhibited the strongest antifungal effects against four plant pathogens by inhibiting mycelial growth and spore germination. This study provided good candidates for chitinous waste-processing enzymes and antifungal biocontrol agents. These synergic chitin-degrading enzymes of SCUT-3 are good targets for its further genetical modification to construct super chitinous waste-degrading bacteria with strong abilities to hydrolyze both protein and chitin, thereby providing a direction for the future path of the chitinous waste recycling industry.

Type 2 diabetes mellitus (DM) accounts for more and more individuals worldwide. D-dimer has been demonstrated to be associated with cardiovascular diseases. The aim is to study the potential impact of D-dimer on the long-term prognosis of acute coronary syndrome (ACS) in the special population with type 2 DM.A total of 2265 consecutive patients with DM and ACS were eligible in the study. Patients were divided into four groups according to quartiles of D-dimer concentration. Univariate and multivariate Cox regression analysis were conducted to explore the prognostic value of D-dimer for future outcomes. Patients with higher level of D-dimer presented with higher percentage of major adverse cardiovascular events (MACEs) (23.7%), all-cause death (18.3%) and cardiovascular (CV) death (9.4%) in Quartile 4. In multivariate Cox regression analysis, D-dimer was demonstrated to be independently associated with MACEs, all-cause death and CV death. The prognostic value of D-dimer is still significant in subgroups of HbA1C7% and ≥7%. In Kaplan-Meier analysis, higher D-dimer showed poorer prognosis in MACEs, all-cause death and CV death (all log rank p 0.001). The area under the curve (AUC) by receiver operating characteristic (ROC) curve analysis is 0.609 for MACEs, 0.708 for all-cause death, 0.747 for CV death (p 0.001).The present study demonstrated the independent predictive value of D-dimer for outcomes in DM patients with ACS. In addition, for the first time, we explored the prognostic value in different glucose control status.

In this paper, the tracking control problem of non-minimum phase flexible air-breathing hypersonic vehicles (AHSV) is investigated subject to actuator fault, external disturbances and parameters uncertainties. The study is began with a series of control-oriented manipulations: first, the input–output dynamics are derived by using feedback linearization method and the internal dynamics of AHSV are constructed; then, the zero dynamics stability analysis is conducted to verify the non-minimum phase characteristic of AHSV. In order to realize output tracking of the non-minimum phase system with sufficient accuracy, an adaptive fault tolerant controller (FTC) is proposed based on an output-redefinition making the zero-dynamics with respect to the new output stable. Additionally, robust adaptive laws are utilized for the estimation of unknown parameters and actuator failure compensation of the AHSV model. Furthermore, the stability of the closed-loop system is analyzed based on the Lyapunov stability theory. At last, the numerical simulation results are provided to demonstrate the effective tracking performance of the proposed FTC scheme.

A gold nanoparticle (AuNP) aggregation-induced colorimetric aptasensing method for quantitative detection of sulfadimethoxine (SDM) with a smartphone was developed. AuNPs were complexed with aptamers which protected AuNPs from aggregating in high-concentration salt solutions. In the presence of SDM, SDM bound with the aptamer on the surface of AuNPs with higher affinity, which competitively desorbed the aptamer from the AuNP surface and resulted in AuNPs aggregation, accompanied with a color change from red to purple-blue. The R, G and B values of images taken by a smartphone camera were analyzed with an app on the smartphone, and were utilized for quantitative analysis of SDM. Under the optimized conditions, the colorimetric aptasensing method using a smartphone showed high sensitivity for SDM, with the limit of detection of 0.023 ppm, lower than the allowed maximum SDM residue limit. This study provides a simple, fast, and easy to read method for on-site quantitative biochemical and cellular analysis.

The complex micromechanical response among grains remains a persistent challenge to understand the deformation mechanism of titanium alloys during cold rolling. Therefore, in this work, a multiscale crystal plasticity finite element method of dual-phase alloy was proposed and secondarily developed based on LS-DYNA software. Afterward, the texture evolution and slip mode of a Ti-5.5Mo-7.2Al-4.5Zr-2.6Sn-2.1Cr alloy, based on the realistic 3D microstructure, during cold rolling (20% thickness reduction) were systematically investigated. The relative activity of the 2 ¯ 0>{0001} slip system in the α phase gradually increased, and then served as the main slip mode at lower Schmid factor ( 2 ¯ 3>{10 1 ¯ 1} slip system to the overall plastic deformation was relatively limited. For the β phase, the relative activity of the {110} slip system showed an upward tendency, indicating the important role of the critical resolved shear stress relationship in the relative activity evolutions. Furthermore, the abnormally high strain of very few β grains was found, which was attributed to their severe rotations compelled by the neighboring pre-deformed α grains. The calculated pole figures, rotation axes, and compelled rotation behavior exhibited good agreement to the experimental results.

Lung cancer is the leading cause of cancer death worldwide. Data on the effectiveness of one-off low-dose CT (LDCT) in reducing lung cancer mortality and all-cause mortality are needed to inform screening programmes in countries with limited medical resources. We aimed to evaluate the effectiveness of one-off LDCT screening in the early detection of lung cancer in China.A multicentre, population-based, prospective cohort study was done in 12 cities of eight provinces across China, recruiting individuals aged 40-74 years who were asymptomatic for lung cancer with no lung cancer history. Participants were classified as at high risk or low risk of lung cancer using a sex-specific risk score that incorporated cigarette smoking, level of physical activity, occupational exposures, history of chronic respiratory diseases, family history of lung cancer, diet, and passive smoking (women only). Participants at high risk were invited for a one-off LDCT scan and were classified into screened and non-screened groups on the basis of whether or not they had the scan. Lung cancer incidence density, lung cancer mortality, and all-cause mortality were calculated for the screened and non-screened groups. The effectiveness of a one-off LDCT scan was evaluated by a comparison of the screened and non-screened groups in terms of lung cancer mortality and all-cause mortality in the period from cohort entry until administrative censoring (June 20, 2020). Inverse probability weighting was adopted to account for potential imbalanced factors between the two groups and Cox proportional hazards model was used to estimate the weighted associations between mortality and one-off LDCT scans.Between Feb 19, 2013, and Oct 31, 2018, 1 032 639 individuals were assessed for eligibility. 1 016 740 participants were enrolled in the study, of whom 3581 had a lung cancer diagnosis after a median follow-up of 3·6 years (IQR 2·8-5·1). Among the 223 302 participants at high risk, 79 581 (35·6%) had an LDCT scan (screened group) and 143 721 (64·4%) did not (non-screened group). After inverse probability weighting, lung cancer incidence density was 47·0% higher (hazard ratio 1·47 [95% CI 1·27-1·70]; p0·0001), lung cancer mortality was 31·0% lower (0·69 [95% CI 0·53-0·92]; p=0·010) and all-cause mortality was 32·0% lower (0·68 [0·57-0·82]; p0·0001) for participants in the screened group compared with those in the non-screened group.One-off LDCT screening was associated with significantly lower lung cancer mortality and all-cause mortality in a large population in China. Our results point to the promise of one-off LDCT screening in countries with limited medical resources. Further studies are needed to explore interactions by subgroup-including sex, age, smoking status, and economic status-to develop population-specific screening strategies.Ministry of Finance and National Health Commission of the People's Republic of China.For the Chinese translation of the abstract see Supplementary Materials section.

Fish culture plays an important role in supplying high-quality proteins and omega-3 (n-3) long-chain polyunsaturated fatty acids. Aquaculture has been the fastest growing sector in agriculture. Fishmeal is an important component of commercial fish feeds, but ensuring a sustainable supply of fishmeal is in question. A good source of proteins in aquafeeds is insects. For the past 20 years, investigations have been carried out on insect meals as alternative sources for fishmeal. Thus far, the results on replacing fishmeal in feeding aquaculture species have been promising. However, some challenging issues including costs and scaling up of insect production remains. In this review, we aim to summarize the status of applying meals of eight insect species in formulated aquafeeds. We also discussed issues in replacing fishmeal in fish feeds with insect meals and listed some future research directions to make insect meals an important source of proteins for green, profitable and sustainable (GPS) aquaculture. It is certain that in the near future, large-scale insect farming and processing to produce insect meals as an ingredient of fish feeds will have positive impact on the sustainability and profitability of aquaculture.

Iridoviruses are DNA virus and have caused huge economic losses in the aquaculture industry. The aim of this study was to establish a colorimetric loop-mediated isothermal amplification (LAMP) protocol for the on-site detection of Singapore grouper iridovirus (SGIV). The SGIV-VP61 gene was chosen as the target gene to develop a colorimetric LAMP assay. The optimized condition of the colorimetric LAMP assay was incubation at 63 °C for 1 h. Samples infected with SGIV could be detected with the color change from yellow into pink. The sensitivity of the developed assay is 5.66 copies/μL of the viral DNA template. This sensitivity was about 1000 times higher than that of conventional PCR while it was slightly lower than the one-step semi-nested PCR assay. A total of 60 DNA samples extracted from the fin tissue of the SGIV-infected Asian seabass were examined for SGIV by colorimetric LAMP, semi-nested PCR and conventional PCR. The results of the colorimetric LAMP assay showed 94.87 % agreement with the semi-nested PCR. In addition, the DNA extraction method using NaOH showed a better performance in the colorimetric LAMP assay. Taken together, the colorimetric LAMP established was a sensitive, rapid and specific method for the detection of SGIV. SGIV was not detected in samples randomly taken from a genetically improved line of the Asian seabass. However, some seabass obtained from the local markets were found to contain SGIV. Thus, the LAMP assay has the potential application in the diagnosis of iridovirus diseases in the aquaculture industry.

The wetting of 3% yttria-stabilized zirconia (YSZ) by Sn–8Zr, Sn–4Zr–4Ti, and Sn–8Ti alloys was studied at 800–900 °C. Both Zr and Ti improve the wettability via the formation of reaction products and adsorption. In the systems containing Zr additives in the alloys, ZrO2-x precipitates preferentially, and the wettability is dominated by interface adsorption. An anomalous temperature dependence was found in the final wettability of these systems owing to the decrease in adsorption with an increase in the temperature. The spreading dynamics are controlled by the dissolution of Zr, followed by the formation of a wetting ridge. The wettability of the Sn–8Ti/YSZ system is dominated by the precipitation of reaction products (Ti2O3 and Ti11.31Sn3O10). The reaction kinetics is the limiting factor for spreading in Sn–8Ti/YSZ, and the adsorption at the interface significantly decreased the energy barrier for wetting.