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The COVID-19 pandemic has forced higher education to enter into a phase of blended learning that combines in-person and mandatory online learning. This new combination has presented great challenges in promoting academic wellbeing. Anchored by the conservation of resources theory, this study undertakes to explore the contributions of personal resources to academic wellbeing. A total of 1934 undergraduates at a public university in China voluntarily participated in a survey during the 2022 spring semester. They were asked to rate their psychological capital (PsyCap) in general. They were also asked to rate their learning burnout, learning engagement, and academic buoyancy on the course level (namely through a course with English as a foreign language). Partial least squares structural equation modelling was used for the data analysis. The results confirm a direct positive association between PsyCap and students' learning engagement. In particular, the contribution of PsyCap to learning engagement is partially mediated by learning burnout. The moderation estimation reports that the positive effect of PsyCap on learning engagement is stronger for Chinese undergraduates with a higher academic buoyancy and that the negative link of learning burnout with either PsyCap or learning engagement is stronger for Chinese undergraduates with a lower academic buoyancy. This research is the first one to explore the beneficial joint roles of PsyCap and academic buoyancy in promoting academic wellbeing. The findings of this research offer novel and subtle insights into why and how PsyCap and academic buoyancy has contributed to easing learning burnout and boosting learning engagement in blended learning environments during the prolonged COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

The healthcare utilization inequality among middle-aged and older adults has been a serious concern shared in the aging process. Successful policy implementation regarding the supply of medical resources and the targeted welfare is an important means to alleviate the healthcare utilization inequalities. However, the effectiveness of the current efforts remains unclear. This study employed self-organizing map and concentration index to explore inequalities in healthcare utilization between age subgroups in similar healthcare settings. The results suggest that utilization inequalities in rich-medical resource regions are not necessarily smaller than those in poor-medical resource regions, which the inpatient and preventive care utilization support the idea. And inequalities of healthcare utilization in rich-medical resource regions show age-lag compared with that in poor-medical resource regions, which indicates a higher level of accessibility to rich medical resources. But rich medical resources still fail to better protect the adults aged 70 and above. The economy, education, and health status, as key contributing factors to the unequal utilization of healthcare, may exacerbate their contribution to inequality in rich-medical resource regions. So a rich supply of healthcare does not necessarily have a one-way positive impact on alleviating inequality in the healthcare utilization. It needs to be combined with other factors to better alleviate inequality. Welfare policy with targeted groups needs to be wary of whether it will lead to greater inequalities. It also called for popularizing free seminar, comprehensive outpatient health management, and serious illness insurance. [ABSTRACT FROM AUTHOR]

In the present study, recombinant Escherichia coli that secretes the multifunctional ɑ-amylase Amy19 was constructed and the induction conditions were optimized. The optimal induction condition obtained by orthogonal experiment was addition of 1.5% glycine for 24 h at 10 ℃. The extracellular secreted multifunctional Amy19 showed the ability to degrade seaweed (Gracilaria verrucosa) waste directly. The reducing sugar concentration increased gradually with degradation time, reaching a maximum (1.047 ± 0.0058 mg mL−1) at 60 h. HPLC showed that the higher degree of polymerization of oligosaccharides decreased gradually, while the content of galactose and 3,6-anhydro-L-galactose gradually increased with time. In the cucumber seed germination experiments, root lengths and seed germination percentages after treatment with enzymatic hydrolysates of seaweed at 5% and 10% concentrations were much greater than after treatment with water or water extracts of seaweed. This may be due to the presence of polysaccharides and oligosaccharide in EHS. In addition, seeds treated with enzymatic hydrolysates of seaweed at lower concentrations showed higher germination indexes and germination energy levels, which were associated with lower mean germination times. Thus, the use of the lower concentrations of enzymatic hydrolysates of seaweed may result in more rapid germination of seeds. This study provides important information for the efficient preparation of recombinant enzyme extracellular secretion and the agricultural applications of seaweed waste. [ABSTRACT FROM AUTHOR]

Uncultured microbes are an important resource for the discovery of novel enzymes. In this study, an amylase gene (amy2587) that codes a protein with 587 amino acids (Amy2587) was obtained from the metagenomic library of macroalgae-associated bacteria. Recombinant Amy2587 was expressed in Escherichia coli BL21 (DE3) and was found to simultaneously possess α-amylase, agarase, carrageenase, cellulase, and alginate lyase activities. Moreover, recombinant Amy2587 showed high thermostability and alkali resistance which are important characteristics for industrial application. To investigate the multifunctional mechanism of Amy2587, three motifs (functional domains) in the Amy2587 sequence were deleted to generate three truncated Amy2587 variants. The results showed that, even though these functional domains affected the multiple substrates degrading activity of Amy2587, they did not wholly explain its multifunctional characteristics. To apply the multifunctional activity of Amy2587, three seaweed substrates (Grateloupia filicina, Chondrus ocellatus, and Scagassum) were digested using Amy2587. After 2 h, 6 h, and 24 h of digestion, 121.2 ± 4 µg/ml, 134.8 ± 6 µg/ml, and 70.3 ± 3.5 µg/ml of reducing sugars were released, respectively. These results show that Amy2587 directly and effectively degraded three kinds of raw seaweeds. This finding provides a theoretical basis for one-step enzymatic digestion of raw seaweeds to obtain seaweed oligosaccharides. [ABSTRACT FROM AUTHOR]

Far Ultraviolet Nighttime Ionopsheric Photometer (FNIP) is a newly-designed instrument for low earth orbit missions, observing the earth night airglow nadir at OI 135.6 nm emission produced by ionospheric O+e recombination and receiving the horizontal information on nighttime ionosphere with a spatial resolution of about 1.6×3.8. This simple, highly robust instrument excludes OI 130.4 nm emission and Herzberg oxygen bands with lower power and approximately achieves a sensitivity of about 400 counts/s/Rayleigh at 135.6 nm with stray light less than 2 %. Some tests of the instrument have been conducted and the results will be discussed in the end. [ABSTRACT FROM AUTHOR]

Objectives: To identify the optimal time window for capturing perfusion information from early C-PIB imaging frames (perfusion PIB, C-pPIB) and to compare the performance of F-FDG PET and "dual biomarker" C-PIB PET [C-pPIB and amyloid PIB (C-aPIB)] for classification of AD, MCI and CN subjects. Methods: Forty subjects (14 CN, 12 MCI and 14 AD patients) underwent F-FDG and C-PIB PET studies. Pearson correlation between the F-FDG image and sum of early C-PIB frames was maximised to identify the optimal time window for C-pPIB. The classification power of imaging parameters was evaluated with a leave-one-out validation. Results: A 7-min time window yielded the highest correlation between F-FDG and C-pPIB. C-pPIB and F-FDG images shared a similar radioactive distribution pattern. F-FDG performed better than C-pPIB for the classification of both AD vs. CN and MCI vs. CN. C-pPIB + C-aPIB and F-FDG + C-aPIB yielded the highest classification accuracy for the classification of AD vs. CN, and F-FDG + C-aPIB had the best classification performance for the classification of MCI vs. CN. Conclusion: C-pPIB could serve as a useful biomarker of rCBF for measuring neural activity and improve the diagnostic power of PET for AD in conjunction with C-aPIB. F-FDG and C-PIB dual-tracer PET examination could better detect MCI. Key Points: • Dual-tracer PET examination provides neurofunctional and neuropathological information for AD diagnosis. • The identified optimal 11C-pPIB time frames had highest correlation with 18F-FDG. • 11C-pPIB images shared a similar radioactive distribution pattern with 18F-FDG images. • 11C-pPIB can provide neurofunctional information. • Dual-tracer PET examination could better detect MCI. [ABSTRACT FROM AUTHOR]

Background: Radiotherapy (RT) following breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS) reduces ipsilateral breast event rates in clinical trials. This study assessed the impact of DCIS treatment on a 20-year risk of ipsilateral DCIS (iDCIS) and ipsilateral invasive breast cancer (iIBC) in a population-based cohort.Methods: The cohort comprised all women diagnosed with DCIS in the Netherlands during 1989-2004 with follow-up until 2017. Cumulative incidence of iDCIS and iIBC following BCS and BCS + RT were assessed. Associations of DCIS treatment with iDCIS and iIBC risk were estimated in multivariable Cox models.Results: The 20-year cumulative incidence of any ipsilateral breast event was 30.6% (95% confidence interval (CI): 28.9-32.6) after BCS compared to 18.2% (95% CI 16.3-20.3) following BCS  +  RT. Women treated with BCS compared to BCS + RT had higher risk of developing iDCIS and iIBC within 5 years after DCIS diagnosis (for iDCIS: hazard ratio (HR)age < 50 3.2 (95% CI 1.6-6.6); HRage ≥ 50 3.6 (95% CI 2.6-4.8) and for iIBC: HRage<50 2.1 (95% CI 1.4-3.2); HRage ≥ 50 4.3 (95% CI 3.0-6.0)). After 10 years, the risk of iDCIS and iIBC no longer differed for BCS versus BCS + RT (for iDCIS: HRage < 50 0.7 (95% CI 0.3-1.5); HRage ≥ 50 0.7 (95% CI 0.4-1.3) and for iIBC: HRage < 50 0.6 (95% CI 0.4-0.9); HRage ≥ 50 1.2 (95% CI 0.9-1.6)).Conclusion: RT is associated with lower iDCIS and iIBC risk up to 10 years after BCS, but this effect wanes thereafter. [ABSTRACT FROM AUTHOR]

An alginate lyase gene aly644 encoding a member of polysaccharide lyase family 6 was obtained from a metagenome of Antarctic macroalgae-associated microbes. The gene was expressed heterologously in Escherichia coli, and the recombinant protein was purified using a Ni-NTA His Tag Kit. With sodium alginate as the substrate, recombinant Aly644 exhibited an optimum reaction temperature of 50°C and an optimum reaction pH of 7.0. The Vmax and Km values of Aly644 toward sodium alginate were 112.36 mg/mL·min and 16.75 mg/mL, respectively. Substrate specificity analysis showed that Aly644 was a bifunctional alginate lyase that hydrolyzed both polyguluronic acid and polymannuronic acid. The hydrolysis products of Aly644 with sodium alginate as the substrate were detected by thin-layer chromatography, and were mainly di- and trisaccharides. The oligosaccharides produced by degradation of sodium alginate by Aly644 inhibited the mycelial growth of the plant pathogens Phytophthora capsici and Fulvia fulva; the 50% maximal effective concentration (EC50) values were 297.45 and 452.89 mg/L, and the 90% maximal effective concentration (EC90) values were 1341.45 and 2693.83 mg/L, respectively. This highlights that Aly644 is a potential candidate enzyme for the industrial production of alginate oligosaccharides with low degree of polymerization. Enzyme-hydrolyzed alginate oligosaccharides could support the development of green agriculture as natural antimicrobial agents. Key points: • An alginate lyase was obtained from a metagenome of Antarctic macroalgae-associated microbes. • Aly644 is a bifunctional alginate lyase with excellent thermostability and pH stability. • The enzymatic hydrolysates of Aly644 directly inhibited Phytophthora capsici and Fulvia fulva. [ABSTRACT FROM AUTHOR]

Ductal carcinoma in-situ (DCIS) accounts for 20–25% of all new breast cancer diagnoses. DCIS has an uncertain risk of progression to invasive breast cancer and a lack of predictive biomarkers may result in relatively high levels (~ 75%) of overtreatment. To identify unique prognostic biomarkers of invasive progression, crystallographic and chemical features of DCIS microcalcifications have been explored. Samples from patients with at least 5-years of follow up and no known recurrence (174 calcifications in 67 patients) or ipsilateral invasive breast cancer recurrence (179 microcalcifications in 57 patients) were studied. Significant differences were noted between the two groups including whitlockite relative mass, hydroxyapatite and whitlockite crystal maturity and, elementally, sodium to calcium ion ratio. A preliminary predictive model for DCIS to invasive cancer progression was developed from these parameters with an AUC of 0.797. These results provide insights into the differing DCIS tissue microenvironments, and how these impact microcalcification formation. [ABSTRACT FROM AUTHOR]

Purpose: Image quality of positron emission tomography (PET) is limited by various physical degradation factors. Our study aims to perform PET image denoising by utilizing prior information from the same patient. The proposed method is based on unsupervised deep learning, where no training pairs are needed. Methods: In this method, the prior high-quality image from the patient was employed as the network input and the noisy PET image itself was treated as the training label. Constrained by the network structure and the prior image input, the network was trained to learn the intrinsic structure information from the noisy image and output a restored PET image. To validate the performance of the proposed method, a computer simulation study based on the BrainWeb phantom was first performed. A 68Ga-PRGD2 PET/CT dataset containing 10 patients and a 18F-FDG PET/MR dataset containing 30 patients were later on used for clinical data evaluation. The Gaussian, non-local mean (NLM) using CT/MR image as priors, BM4D, and Deep Decoder methods were included as reference methods. The contrast-to-noise ratio (CNR) improvements were used to rank different methods based on Wilcoxon signed-rank test. Results: For the simulation study, contrast recovery coefficient (CRC) vs. standard deviation (STD) curves showed that the proposed method achieved the best performance regarding the bias-variance tradeoff. For the clinical PET/CT dataset, the proposed method achieved the highest CNR improvement ratio (53.35% ± 21.78%), compared with the Gaussian (12.64% ± 6.15%, P = 0.002), NLM guided by CT (24.35% ± 16.30%, P = 0.002), BM4D (38.31% ± 20.26%, P = 0.002), and Deep Decoder (41.67% ± 22.28%, P = 0.002) methods. For the clinical PET/MR dataset, the CNR improvement ratio of the proposed method achieved 46.80% ± 25.23%, higher than the Gaussian (18.16% ± 10.02%, P < 0.0001), NLM guided by MR (25.36% ± 19.48%, P < 0.0001), BM4D (37.02% ± 21.38%, P < 0.0001), and Deep Decoder (30.03% ± 20.64%, P < 0.0001) methods. Restored images for all the datasets demonstrate that the proposed method can effectively smooth out the noise while recovering image details. Conclusion: The proposed unsupervised deep learning framework provides excellent image restoration effects, outperforming the Gaussian, NLM methods, BM4D, and Deep Decoder methods. [ABSTRACT FROM AUTHOR]

Retrieval experiment was made for global total column ozone using the first year measurements of Total Ozone Unit (TOU) on board the second generation polar orbiting meteorological satellite of China, FY-3/A. The retrieval results were analyzed and validated by comparison with AURA/OMI, Meteop/GOME-2 global ozone products and ground-based ozone measurement data. The qualititative comparisons over the globe especially over Antarctica and the Tibetan Plateau show that the spatial and temporal distribution characteristics are consistent with OMI and GOME-2 products. The quantitative comparisons with ground-based measurements and AURA/OMI ozone product were made over 74 stations, the TOU total ozone retrieval has a 3% rms relative error compared with AURA/OMI ozone product and 4.2% rms relative error with ground-based measurements. The maximum difference between satellite retrieval and ground-based measurements was found in the Antarctica ozone hole. The TOU global ozone product is operational and distributed to all users. [ABSTRACT FROM AUTHOR]

FY-3 satellites are Chinese second-generation polar orbit meteorological satellite series. Ultraviolet Total Ozone Unit (TOU) is one of the main payloads on FY-3 satellite and the first instrument for daily global coverage of total ozone monitoring in China. The main purpose of TOU is to measure the Earth backscatter ultraviolet radiation for retrieving daily global map of atmospheric ozone. TOU will provide the important parameters for environmental monitoring, climate forecasting and global climate changing research. At present, the in-orbit testing of TOU has accomplished and won a consummation, and it will be delivered to National Satellite Meteorological Center for the operational phase of the project. In this paper we introduce the instrument of TOU and its measuring principle, in general. We also analyze the recent working status of the instrument, including the sensitivity, measuring precision of solar irradiance, diffuser degradation and wavelength drift. The inversion results show that TOU can provide good global ozone maps, and a comparison with the OMI total ozone product shows that their RMS deviation is about 5%. It is indicated that the satisfied global distribution of total ozone can be obtained through TOU observational data and self-developed inversion method. [ABSTRACT FROM AUTHOR]