The Influence of Alkali Content on the Hydration of the Slag-Based Geopolymer: Relationships between Resistivity, Setting, and Strength Development

This study investigated the influence of alkali content on the early-age hydration process of slag-based geopolymer and the feasibility of non-destructive resistivity. Results showed that there existed a threshold of alkali content in adjusting the early-age hydration. Initially, increasing the alkali content tended to accelerate the dissolution period (detected by resistivity and heat release rate) and resulted in a denser microstructure (detected by TEM). When the alkali content surpassed 6 wt%, the increasing alkali content mitigated the structural development of a slag-based geopolymer, as it lowered the liquid water content and caused local precipitation, which trapped the early-age ions transmission and, therefore, the later-age mechanical development was inhibited. It was proven that the resistivity acted as a linkage among the reaction degree, workability, and strength development

Multimodal and Multi-Model Deep Fusion for Fine Classification of Regional Complex Landscape Areas Using ZiYuan-3 Imagery

Land cover classification (LCC) of complex landscapes is attractive to the remote sensing community but poses great challenges. In complex open pit mining and agricultural development landscapes (CMALs), the landscape-specific characteristics limit the accuracy of LCC. The combination of traditional feature engineering and machine learning algorithms (MLAs) is not sufficient for LCC in CMALs. Deep belief network (DBN) methods achieved success in some remote sensing applications because of their excellent unsupervised learning ability in feature extraction. The usability of DBN has not been investigated in terms of LCC of complex landscapes and integrating multimodal inputs. A novel multimodal and multi-model deep fusion strategy based on DBN was developed and tested for fine LCC (FLCC) of CMALs in a 109.4 km2 area of Wuhan City, China. First, low-level and multimodal spectral–spatial and topographic features derived from ZiYuan-3 imagery were extracted and fused. The features were then input into a DBN for deep feature learning. The developed features were fed to random forest and support vector machine (SVM) algorithms for classification. Experiments were conducted that compared the deep features with the softmax function and low-level features with MLAs. Five groups of training, validation, and test sets were performed with some spatial auto-correlations. A spatially independent test set and generalized McNemar tests were also employed to assess the accuracy. The fused model of DBN-SVM achieved overall accuracies (OAs) of 94.74% ± 0.35% and 81.14% in FLCC and LCC, respectively, which significantly outperformed almost all other models. From this model, only three of the twenty land covers achieved OAs below 90%. In general, the developed model can contribute to FLCC and LCC in CMALs, and more deep learning algorithm-based models should be investigated in future for the application of FLCC and LCC in complex landscapes

Risk factors associated with prolonged viral clearance in patients with a refractory course of COVID-19: a retrospective study

Background This study aimed to characterize a cohort of patients with a refractory course of COVID-19, and to investigate factors associated with the duration of viral clearance (DoVC). Materials & Methods A total of 65 patients with refractory COVID-19 were retrospectively enrolled from Huoshenshan Hospital. Univariate analysis and multivariate analysis were performed to examine the potential association between clinicopathologic characteristics and the DoVC. Results The median DoVC in the overall study cohort was 48 days (ranged from 21 to 104 days). Multivariate analysis indicated that fever at illness onset (Hazard ratio (HR) = 4.897, 95% CI [1.809–13.260], p = 0.002), serum level of aspartate aminotransferase (AST) > 21.8 IU/L (HR = 3.010, 95% CI [1.195–7.578], p = 0.019), and titer of SARS-CoV-2 IgG > 142.09 AU/ml (HR = 3.061, 95% CI [1.263–7.415], p = 0.013) were the three independent risk factors associated with delayed viral clearance. Conclusion The current study suggested that clinical characteristics such as fever at illness onset, a high serum level of AST or SARS-CoV-2 IgG were associated with delayed viral clearance. Patients with these characteristics might need a more individualized treatment strategy to accelerate their recovery from the refractory COVID-19

A spatio-temporal multiplexing multi-view display using a lenticular lens and a beam steering screen

A new type of spatio-temporal multiplexing multi-view three-dimensional (3D) display with horizontal motion parallax has been developed. The proposed 3D display system comprises: a fast liquid-crystal-display (LCD), a lenticular lens and a beam steering screen. The lenticular lens is customized for the LCD screen so as to project the display image into different directions. The beam steering screen is fabricated by using two layers of twisted-nematic (TN) LC cells with micro-prism-array(MPA) substrates, and multiple polarization statues can be produced by regulating the biasing voltages on the steering screen. Image light beam from the LCD screen is firstly split by the lenticular lens, and then further deflected to desired directions by the steering screen. Thus, the proposed method implements temporal multiplexing onto common spatial multiplexing multi-view displays, and dense viewing zones are created horizontally in space. A complete prototype based on this technology has been developed, and the proof of concept has been verified by experimental results.NRF (Natl Research Foundation, S’pore)Accepted versio

Addressable spatial light modulators for eye-tracking autostereoscopic three-dimensional display using a scanning laser

A scanning laser-based back light three-dimensional (3D) display capable of rendering full-resolution, low crosstalk, and vivid 3D depth perception has been developed by incorporating time-sequential multiplexing and eye-tracking technologies. This system includes three main subsystems: a scanning laser module, a relay transfer unit created by combining multiple transmissive-type electrically addressed ferroelectric liquid crystal spatial light modulators (FLC-SLMs), and a dual-directional transmission screen (DDTS) unit that can produce different angular magnification factors in both the tangential and sagittal planes. The light beam is directed by the DDTS after transmission through FLC-SLMs, and left and right eye viewing zones are produced sequentially in accordance with the locations of clear apertures in the FLC-SLM that are controlled based on data from the eye-tracking system. Owing to the persistence of human vision, 3D images are formed as a result of the high-speed scanning backlight and fast response characteristics of the FLC-SLM. A prototype of the proposed 3D display was designed and built, and experiments were carried out. The experimental results verify the feasibility of the proposed scheme, and full-resolution images with natural 3D perception are demonstrated by the prototype.NRF (Natl Research Foundation, S’pore

Misconception contributed to COVID-19 vaccine hesitancy in patients with lung cancer or ground-glass opacity: a cross-sectional study of 324 Chinese patients

Patients highly vulnerable for COVID-19 infection have been proposed to take priority for vaccination. However, vaccine hesitancy is usually more prevalent in these patients. Investigation around modifiable contributors of vaccine hesitancy plays a pivotal role in the formulation of coping strategies. We aimed to evaluate the impact of vaccine misconception in patients with lung cancer or pulmonary ground-glass opacity (GGO). A web-based questionnaire was constructed based on a qualitative interview with 15 patients and reviewed by a multidisciplinary expert panel. Six Likert five-scale questions were used to generate a score of vaccine misconception (SoVM), which ranged from 0 to 24 points, with a higher score indicating a higher level of misconception. A total of 61.6% (324/526) patients responded to our questionnaire. A higher proportion of low willingness patients (n = 173), compared to high willingness patients (n = 151), disagreed that cancer patients should be prioritized for COVID-19 vaccination (82.1% vs. 50.3%, p < .001) and perceived themselves to have contraindications (45.7% vs. 15.9%, p < .001). The mean SoVM was significantly lower in the high willingness group than the low willingness group (9.9 vs. 13.0, p < .001). Among the unvaccinated patients, the SoVM increased as the willingness to be vaccinated decreased (p < .0001). In multivariable logistic regression, patients with higher SoVM (OR 0.783, 95% CI 0.722–0.848), being female (OR 0.531, 95% CI 0.307–0.918) or diagnosed with lung cancer (OR 0.481, 95% CI 0.284–0.814) were independently associated with a lower willingness to be vaccinated against COVID-19. Receiver operating characteristic curve suggested that a SoVM of 11 yielded the best discrimination for predicting the willingness to receive COVID-19 vaccine (AUC = 0.724). The study findings reveal that patient misconception significantly contributes to vaccine hesitancy and needs to be addressed by evidence-based education tailored to their specific concerns

Investigation on sleep quality and psychological distress in patients with pulmonary nodules

Abstract Background Patients with pulmonary nodules (PNs) often suffer from the psychological burden of their disease and trap in sleep problems. This is insufficiently identified and addressed in clinical practice. The aim of this study was to investigate the psychological distress and sleep quality among PN patients and identify potential risk or protective factors for sleep quality. Methods We conducted a cross-sectional study, which included 731 PN patients who visited the thoracic clinic of Guangdong Provincial People’s Hospital. Each participant completed a structured questionnaire consisting of demographic characteristics, clinical characteristics, the Hospital Anxiety and Depression Scale (HADS) and the Pittsburgh Sleep Quality Index (PSQI). The reliability of the HADS (Cronbach’s α = 0.944) and PSQI (Cronbach’s α = 0. 0.757) in this study was satisfactory. Results A total of 328 patients (44.9%) had PSQI global scores > 5, indicating poor quality of sleep. Age ≥ 50 years (OR 1.88, 95% CI 1.35–2.58; P < 0.001), female (OR 1.56, 95% CI 1.05–2.33; P = 0.028), detection of nodule for 7–12 months (vs for more than 24 months, OR 2.14, 95%CI 1.18–3.89, P = 0.013), anxiety (OR 1.78, 95% CI 1.17–2.71; P = 0.007) and depression (OR 1.84, 95% CI 1.16–2.92; P = 0.010) were independent risk factors for impaired sleep quality. A significant correlation revealed that sleep quality was positively correlated with both anxiety and depression (Spearman r = 0.342, P < 0.001 and Spearman r = 0.314, P < 0.001, respectively). All dimensions of the PSQI scale were significantly decreased in both anxiety group and depression group compared to the psychologically normal group (P < 0.05). Conclusions Impaired sleep quality is highly prevalent among patients with PNs and associated with age, gender, time from the date of detection, anxiety and depression. Based on the finding of impaired sleep quality and psychological health, screening for psychological and sleep problems in PN patients will be of great clinical benefit

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensing

Graphene-embedded plant tissues show a high sensitivity to electrochemical signals, which enables a screen printed electrode to be used for electrochemical fingerprint recording. The electrochemical fingerprints obtained under different conditions can be transformed into multidimensional recognition modes for plant identification. These electrochemical fingerprints reflect the types and quantities of the electrochemically active substances in plant tissues such that the fingerprints can be used for chemotaxonomic investigations. In this paper, five species of Lycoris bulbs, including L. chinensis, L. radiate, L. aurea, L. sprengeri and L. straminea, were successfully recognized by electrochemical fingerprinting. The species's interspecific relationships were also investigated. L. chinensis and L. aurea show highly similar morphology but have a relatively distant relationship. Hybridized L. radiata shows a notably close relationship with L. straminea, suggesting that one of its parents may be L. radiata. In addition, L. chinensis also shows a close relationship with L. straminea, suggesting that the L. straminea may be produced by cross-breeding L. chinensis and L. radiate. The results mentioned above indicate that the proposed electro-chemotaxonomic methodology is an inexpensive and quick taxonomic method that can provide additional evidence for the existing taxonomy system

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensing

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensin

Enhanced electrochemical voltammetric fingerprints for plant taxonomic sensing

Graphene-embedded plant tissues show a high sensitivity to electrochemical signals, which enables a screen printed electrode to be used for electrochemical fingerprint recording. The electrochemical fingerprints obtained under different conditions can be transformed into multidimensional recognition modes for plant identification. These electrochemical fingerprints reflect the types and quantities of the electrochemically active substances in plant tissues such that the fingerprints can be used for chemotaxonomic investigations. In this paper, five species of Lycoris bulbs, including L. chinensis, L. radiate, L. aurea, L. sprengeri and L. straminea, were successfully recognized by electrochemical fingerprinting. The species's interspecific relationships were also investigated. L. chinensis and L. aurea show highly similar morphology but have a relatively distant relationship. Hybridized L. radiata shows a notably close relationship with L. straminea, suggesting that one of its parents may be L. radiata. In addition, L. chinensis also shows a close relationship with L. straminea, suggesting that the L. straminea may be produced by cross-breeding L. chinensis and L. radiate. The results mentioned above indicate that the proposed electro-chemotaxonomic methodology is an inexpensive and quick taxonomic method that can provide additional evidence for the existing taxonomy system