Advanced "turn-on" colorimetric uranium platform based on the enhanced nanozyme activity of a donor-acceptor structured covalent organic framework.

BACKGROUND: The increasing uranium containing wastes generated during uranium mining and finishing pose a huge threat to the environment and human health, and thus robust strategies for on-site monitoring of uranium pollutant are of great significance for environmental protection around uranium tailings. RESULTS: Herein, a facile "turn-on" colorimetric platform that can achieve uranium detection by spectrometry and naked eyes was developed based on the uranium-enhanced nanozyme activity of covalent organic framework (JUC-505). Thanks to the extended π-conjugated skeleton and donor-acceptor (D-A) structure, JUC-505 exhibited superior photo-activated nanozyme activity, which would be prohibited when the cyano group in JUC-505 skeleton was transformed to the amidoxime group. Further results elucidated that the coordination of uranium with amidoxime groups led to the electron transfer between uranium and the JUC-505-AO skeleton, and thus significantly restored the nanozymatic activity of JUC-505-AO with the subsequent remarkable color changes. Moreover, the uranium concentrations in uranium tailing wastewater detected by the present "turn-on" colorimetric method were well agreed with those by ICP-MS, demonstrating a high accuracy of the present method in real samples. SIGNIFICANCE: The D-A structured JUC-505 with superior photocatalytic property and nanozymatic activity was applied to facilitate colorimetric detection of uranium, which displays the advantages of low detection limit, excellent selectivity, fast response and simple operation for uranium detection in real samples, and shows a great potential in on-site monitoring of uranium pollutant around uranium tailings as well as nuclear power plant.

Promoting the Aging Process and Enhancing the Production of Antioxidant Components of Garlic through Pulsed Electric Field Treatments.

Shortening the aging duration and enhancing the functional components of garlic present significant technical challenges that need to be addressed. Thus, this study aimed to evaluate the potential role of pulsed electric field (PEF) treatment, a novel nonthermal food processing method, in promoting and enhancing the functional attributes of aged garlic. Our results showed that 2-4 kV/cm PEF pretreatment increased S-allyl cysteine (SAC), total polyphenol (TPC), and flavonoid contents (TFC) compared with un-pretreated garlic during aging. The browning and texture-softening were also significantly improved during processing time, though the latter showed no significant difference from the eighth day to the end of the aging process. The principal component analysis results showed that PEF positively affects the SAC and TFC formations without adverse effects. Among the PEF pretreatments, 3 kV/cm is the most effective in enhancing functional component production compared with the other PEF pretreatments. Therefore, PEF pretreatment is a time-saving process that promotes and enhances the functionality of aged garlic.

Addressing the long-standing limitations of double exponential and non-rectangular hyperbolic models in quantifying light-response of electron transport rates in different photosynthetic organisms under various conditions.

The models used to describe the light response of electron transport rate in photosynthesis play a crucial role in determining two key parameters i.e., the maximum electron transport rate (J max) and the saturation light intensity (I sat). However, not all models accurately fit J-I curves, and determine the values of J max and I sat. Here, three models, namely the double exponential (DE) model, the non-rectangular hyperbolic (NRH) model, and a mechanistic model developed by one of the coauthors (Z-P Ye) and his coworkers (referred to as the mechanistic model), were compared in terms of their ability to fit J-I curves and estimate J max and I sat. Here, we apply these three models to a series of previously collected Chl a fluorescence data from seven photosynthetic organisms, grown under different conditions. Our results show that the mechanistic model performed well in describing the J-I curves, regardless of whether photoinhibition/dynamic down-regulation of photosystem II (PSII) occurs. Moreover, both J max and I sat estimated by this model are in very good agreement with the measured data. On the contrary, although the DE model simulates quite well the J-I curve for the species studied, it significantly overestimates both the J max of Amaranthus hypochondriacus and the I sat of Microcystis aeruginosa grown under NH4 +-N supply. More importantly, the light intensity required to achieve the potential maximum of J (J s) estimated by this model exceeds the unexpected high value of 105 µmol photons m-2 s-1 for Triticum aestivum and A. hypochondriacus. The NRH model fails to characterize the J-I curves with dynamic down-regulation/photoinhibition for Abies alba, Oryza sativa and M. aeruginosa. In addition, this model also significantly overestimates the values of J max for T. aestivum at 21% O2 and A. hypochondriacus grown under normal condition, and significantly underestimates the values of J max for M. aeruginosa grown under NO3 -N supply. Our study provides evidence that the 'mechanistic model' is much more suitable than both the DE and NRH models in fitting the J-I curves and in estimating the photosynthetic parameters. This is a powerful tool for studying light harvesting properties and the dynamic down-regulation of PSII/photoinhibition.

Detection of basic amino acids under highly alkaline conditions using a perylene amine-derived probe.

pH plays a crucial part in numerous chemical and physiological processes. In this work, a new perylene diimide derivative that acts as a pH-sensitive dye with Bay Area Carboxylic Acid functionality. The derivative utilizes the outstanding thermal, chemical and photochemical stability found in PDI materials and has remarkable UV-visible absorption and fluorescence emission qualities. Based on these properties, a fluorescent probe (PCA) was synthesised using a perylene tetracarbodiimide (PDI) backbone for the recognition of alkaline pH. In alkaline environments where the pH values are between 10 and 14, the fluorescence intensity significantly decreases, and a blue shift occurs, which is a standard feature of alkaline pH probes. The probe demonstrates exceptional sensing ability within the pH range of 10.00-14.00, with notable stability and reversibility. Encapsulation of the probe in a thin polymer film material enhances the pH sensing capability of the system. New sensor has been developed to detect basic amino acids by utilizing the probes' pH response characteristics. this sensor has also been applied to detect the concentration of arginine.

Distal Pancreatectomy: Extent of Resection Determines Surgical Risk Categories.

BACKGROUND: Recently, subclassification of pancreatoduodenectomy in 4 differing types has been reported, because additional major vascular and multivisceral resections have been shown to be associated with an increased risk of postoperative morbidity and mortality. OBJECTIVE: To classify distal pancreatectomy (DP) based on the extent of resection and technical difficulty and to evaluate postoperative outcomes with regards to this classification system. METHODS: All consecutive patients who had undergone DP between 2001 and 2020 in a high-volume pancreatic surgery center were included in this study. DPs were subclassified into 4 distinct categories reflecting the extent of resection and technical difficulty, including standard DP (type 1), DP with venous (type 2), multivisceral (type 3), or arterial resection (type 4). Patient characteristics, perioperative data, and postoperative outcomes were analyzed and compared among the 4 groups. RESULTS: A total of 2135 patients underwent DP. Standard DP was the most frequently performed procedure (64.8%). The overall 90-day mortality rate was 1.6%. Morbidity rates were higher in patients with additional vascular or multivisceral resections, and 90-day mortality gradually increased with the extent of resection from standard DP to DP with arterial resection (type 1: 0.7%; type 2: 1.3%; type 3: 3%; type 4: 8.7%; P <0.0001). Multivariable analysis confirmed the type of DP as an independent risk factor for 90-day mortality. CONCLUSIONS: Postoperative outcomes after DP depend on the extent of resection and correlate with the type of DP. The implementation of the 4-type classification system allows standardized reporting of surgical outcomes after DP improving comparability of future studies.

Long-term Cardiovascular, Cerebrovascular, and Other Thrombotic Complications in COVID-19 Survivors: A Retrospective Cohort Study.

BACKGROUND: Growing evidence suggests that some coronavirus disease 2019 (COVID-19) survivors experience a wide range of long-term postacute sequelae. We examined the postacute risk and burden of new-incident cardiovascular, cerebrovascular, and other thrombotic complications after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a highly vaccinated multiethnic Southeast Asian population, during Delta predominance. METHODS: This cohort study used national testing and healthcare claims databases in Singapore to build a cohort of individuals who had a positive SARS-CoV-2 test between 1 September and 30 November 2021 when Delta predominated community transmission. Concurrently, we constructed a test-negative control group by enrolling individuals between 13 April 2020 and 31 December 2022 with no evidence of SARS-CoV-2 infection. Participants in both groups were followed up for a median of 300 days. We estimated risks of new-incident cardiovascular, cerebrovascular, and other thrombotic complications using doubly robust competing-risks survival analysis. Risks were reported using 2 measures: hazard ratio (HR) and excess burden (EB) with 95% confidence intervals. RESULTS: We included 106 012 infected cases and 1 684 085 test-negative controls. Compared with the control group, individuals with COVID-19 exhibited increased risk (HR, 1.157 [1.069-1.252]) and excess burden (EB, 0.70 [.53-.88]) of new-incident cardiovascular and cerebrovascular complications. Risks decreased in a graded fashion for fully vaccinated (HR, 1.11 [1.02-1.22]) and boosted (HR, 1.10 [.92-1.32]) individuals. Conversely, risks and burdens of subsequent cardiovascular/cerebrovascular complications increased for hospitalized and severe COVID-19 cases (compared to nonhospitalized cases). CONCLUSIONS: Increased risks and excess burdens of new-incident cardiovascular/cerebrovascular complications were reported among infected individuals; risks can be attenuated with vaccination and boosting.

Long-term neuropsychiatric sequelae of Delta versus Omicron SARS-CoV-2 infection.

OBJECTIVES: Studies have reported increased rates of long-term neuropsychiatric sequelae after SARS-CoV-2 infection using electronic health-record (EHR) data; however, the majority were conducted before Omicron and booster rollout. We estimated the long-term risks and excess burdens of pre-specified new-incident neuropsychiatric diagnoses after Delta versus Omicron BA.1/2 infection in a highly-vaccinated and boosted cohort of adult Singaporeans. METHODS: The national SARS-CoV-2 testing registry was used to construct cohorts of Singaporean adults infected during periods of Delta and Omicron BA.1/2 predominance and a contemporaneous test-negative control group. New-incident neuropsychiatric diagnoses recorded in the national health care claims database were identified up to 300 days postinfection. Risks and excess burden were estimated using a doubly robust competing-risks survival analysis. RESULTS: 104 179 and 375 903 infected cases were assigned to Delta and Omicron cohorts and compared against test-negative controls (Delta: N = 666 575 and Omicron: N = 619 379). Elevated risk of cognition or memory disorders was consistently reported across Omicron (Adjusted hazards ratio [aHR], 1.24; 95% CI, 1.12-1.38) and Delta cohorts (aHR, 1.63; 95% CI, 1.39-1.92). Delta-variant infection was associated with an increased risk of anosmia or dysgeusia (aHR, 4.53; 95% CI, 2.78-7.41) and psychosis (aHR, 1.65; 95% CI, 1.22-2.22). By contrast, Omicron-variant infection was associated with a risk of abnormal involuntary movements (aHR, 1.93; 95% CI, 1.32-2.83). Risks of neuropsychiatric sequelae predominantly accrued in hospitalized individuals. DISCUSSIONS: A modestly increased risk of cognition and memory disorders at 300 days after SARS-CoV-2 infection was observed among adult Singaporeans infected during the Delta/Omicron BA.1/2 transmission. There was no overall increased risk of neuropsychiatric sequelae observed across other domains. Variant-specific differences were also observed in individual neuropsychiatric sequelae, including an elevated risk of anosmia or dysgeusia after Delta-variant infection.

Polypharmacy and potential drug-drug interactions among people living with HIV in the era of integrase strand transfer inhibitor-based antiretroviral therapy.

OBJECTIVES: To investigate the prevalence of polypharmacy and potential drug-drug interactions (DDIs), and the factors associated with DDIs among people living with human immunodeficiency virus (HIV; PLWH) in the modern era of antiretroviral therapy (ART). METHODS: This cross-sectional study included PLWH who had been on ART for ≥3 months at two designated HIV hospitals in Taiwan. All ART and non-ART prescriptions were collected from the NHI-MediCloud System and screened for DDIs using the University of Liverpool HIV drug interactions database. A case-control analysis was conducted to investigate the factors associated with DDIs. RESULTS: In total, 1007 PLWH were included in this study from June 2021 to August 2022. The median age was 40 (interquartile range 33-49) years, and 96.2% were taking integrase strand transfer inhibitor (INSTI)-based ART. The proportions of PLWH with at least one non-communicable disease and polypharmacy were 50.0% and 18.7%, respectively. Seven (0.7%) PLWH had red-flagged DDIs, and 159 (15.8%) had amber-flagged DDIs. In multi-variable models, the prevalence of DDIs was associated with older age [adjusted odds ratio (aOR) per 1-year increase 1.022), number of co-medications (aOR 1.097), use of boosted INSTI-based ART (vs unboosted INSTI, aOR 8.653), and concomitant medications in the alimentary tract and metabolism category (aOR 11.058) and anti-neoplastic and immunomodulating agents (aOR 14.733). CONCLUSIONS: In the INSTI era, the prevalence of potential DDIs is lower than noted previously, but remains substantial. Clinicians should monitor DDIs routinely, especially in older PLWH, those taking a higher number of co-medications, and those who are taking booster-containing ART or medications from specific categories.

Gallic acid attenuates metastatic potential of human colorectal cancer cells through the miR-1247-3p-modulated integrin/FAK axis.

Colorectal cancer (CRC) exhibits highly metastatic potential even in the early stages of tumor progression. Gallic acid (GA), a common phenolic compound in plants, is known to possess potent antioxidant and anticancer activities, thereby inducing cell death or cell cycle arrest. However, whether GA reduces the invasiveness of CRC cells without inducing cell death remains unclear. Herein, we aimed to investigate the antimetastatic activity of low-dose GA on CRC cells and determine its underlying mechanism. Cell viability and tumorigenicity were analyzed by MTS, cell adhesion, and colony formation assay. Invasiveness was demonstrated using migration and invasion assays. Changes in protein phosphorylation and expression were assessed by Western blot. The involvement of microRNAs was validated by microarray analysis and anti-miR antagonist. Our findings showed that lower dose of GA (≤100 µM) did not affect cell viability but reduced the capabilities of colony formation, cell adhesion, and invasiveness in CRC cells. Cellularly, GA downregulated the cellular level of integrin αV/ß3, talin-1, and tensin and diminished the phosphorylated FAK, paxillin, Src, and AKT in DLD-1 cells. Microarray results revealed that GA increased miR-1247-3p expression, and pretreatment of anti-miR antagonist against miR-1247-3p restored the GA-reduced integrin αV/ß3 and the GA-inhibited paxillin activation in DLD-1 cells. Consistently, the in vivo xenograft model showed that GA administration inhibited tumor growth and liver metastasis derived from DLD-1 cells. Collectively, our findings indicated that GA inhibited the metastatic capabilities of CRC cells, which may result from the suppression of integrin/FAK axis mediated by miR1247-3p.

Evaluating spatial policies without indicators: A study on Taiwan as a developmental state in transition.

Policy evaluations are crucial in promoting effective administrations. However, evaluations of spatial policies are rare, due to its ambiguity and complexity. Especially when a developmental state transitions to democracy, the loss of top-down leadership disables formulation of indicators for evaluations. In such cases, it is essential to search for new evaluation methods and approaches. This paper introduces a Taiwanese and East Asian context, with a unique historical path toward democracy, which is rarely discussed regarding policy evaluation, especially spatial policy evaluation. As the "hard" developmental states democratize and value more human aspects instead of sheer economic development, compared with "hard" methods such as quantitative impact evaluations, "soft" measures like process evaluation, participatory evaluation and self-assessment may enhance cross-departmental dialogues and connections between policies and executors. With humans at the center of space use and policy making, this research explores the possibility of bottom-up evaluation without indicators. The new ideas proposed here bridge the vacancies of power dominance in developmental states during transition, and serve as references for such states in current times, especially in the Asian region.

An observational study on salivary conductivity for fluid status assessment and clinical relevance in acute ischemic stroke during intravenous fluid hydration.

The body fluid status in acute stroke is a crucial determinant in early stroke recovery but a real-time method to monitor body fluid status is not available. This study aims to evaluate the relationship between salivary conductivity and body fluid status during the period of intravenous fluid hydration. Between June 2020 to August 2022, patients presenting with clinical signs of stroke at the emergency department were enrolled. Salivary conductivities were measured before and 3 h after intravenous hydration. Patients were considered responsive if their salivary conductivities at 3 h decreased by more than 20% compared to their baseline values. Stroke severity was assessed using the National Institutes of Health Stroke Scale, and early neurological improvement was defined as a decrease of ≥ 2 points within 72 h of admission. Among 108 recruited patients, there were 35 of stroke mimics, 6 of transient ischemic attack and 67 of acute ischemic stroke. Salivary conductivity was significantly decreased after hydration in all patients (9008 versus 8118 µs/cm, p = 0.030). Among patients with acute ischemic stroke, the responsive group, showed a higher rate of early neurological improvement within 3 days compared to the non-responsive group (37% versus 10%, p = 0.009). In a multivariate logistic regression model, a decrease in salivary conductivity of 20% or more was found to be an independent factor associated with early neurological improvement (odds ratio 5.42, 95% confidence interval 1.31-22.5, p = 0.020). Real-time salivary conductivity might be a potential indicator of hydration status of the patient with acute ischemic stroke.

Red Room-Temperature Phosphorescence Supramolecular Assemblies Based on Cucurbit[7]uril: Reversible Temperature Stimulation Response and Cell-Specific Silver Ion Imaging.

Solid-state materials with efficient room-temperature phosphorescence (RTP) emission have been widely used in materials science, and organic RTP-emitting systems with heavy-metal doping in aqueous solutions have attracted much attention in recent years. A novel supramolecular interaction was induced by host-guest assembly using cucurbit[7]uril (Q[7]) as the host and brominated naphthalimide phosphor as the guest. This interaction was further enhanced through synergistic chelation stimulated by analytical silver ion complexation. This approach facilitated the system's structural rigidity, intersystem crossing, and oxygen shielding. We achieved deep red phosphorescence emission in aqueous solution and ambient conditions along with quantitative determination of silver ions. The new complex exhibited good reversible thermoresponsive behavior and was successfully applied for the first time to target phosphorescence imaging of silver ions in the mitochondria of A549 cancer cells. These results are beneficial for constructing novel RTP systems with stimulus-responsive luminescence in aqueous solution, contributing to future research in bioimaging, detection, optical sensors, and thermometry materials.

Efficacy of lidocaine wet compress combined with red-light irradiation for chronic wounds.

BACKGROUND: Chronic wounds that fail to progress through normal phases of healing present a significant healthcare burden owing to prolonged treatment and associated costs. Traditional wound care typically involves regular dressing changes, which can be painful. Recent approaches have explored the use of lidocaine to manage pain and red-light irradiation (RLI), known for its anti-inflammatory and cell proliferation effects, to potentially enhance wound healing. AIM: To investigate the therapeutic efficacy of lidocaine wet compression (LWC) combined with RLI for chronic wounds. METHODS: We enrolled 150 patients with chronic wounds from the Wound and Ostomy Outpatient Clinic of the Second Hospital of Anhui Medical University from April to September 2022. The wounds were treated with dressing changes. The patients were randomly assigned to the control and experimental groups using a random number table and given the same first dressing change (2% LWC for 5 min and routine dressing change). From the second dressing change, in addition to 2% LWC for 5 min and routine dressing change, the experimental group received RLI, whereas the control group continued to receive the same LWC and dressing change. The first and second dressing changes were performed on days 1 and 2, respectively. The third dressing change was performed 3 d after the second change. The frequency of subsequent dressing changes was determined based on wound exudation and pain. Pain during the first three dressing changes was evaluated in both groups. The average number of dressing changes within 28 d and the degree of wound healing on day 28 were also recorded. RESULTS: During the initial dressing change, no noticeable differences were observed in the pain levels experienced by the two groups, indicating similar pain tolerance. However, during the second and third dressing changes, the experimental group reported significantly less pain than the control group. Furthermore, over 28 d, the experimental group required fewer dressing changes than the control group. CONCLUSION: Notably, the effectiveness of wound healing on the 28th day was significantly higher in the experimental group than that of in the control group. The combination of LWC and RLI was effective in reducing early-stage pain, promoting wound healing, decreasing the frequency of dressing changes, and enhancing patients' overall quality of life with chronic wounds.

Cucurbit[7]uril-based carbon dots for recognizing histamine.

Fluorescent carbon quantum dots (CQDs) were synthesized from cucurbit[7]uril (Q[7]) and 2,2-bis(hydroxymethyl)propionic (DMPA) by a hydrothermal method. The Q[7]-DMPA complex was confirmed by X-ray crystallography. The CQDs showed blue fluorescence, photostability, and ionic strength stability. They were used to detect histamine with a low limit of 2.33 × 10-6 M.

De novo biosynthesis of anticarcinogenic icariin in engineered yeast.

Icariin (ICA) has wide applications in nutraceuticals and medicine with strong anticancer activities. However, the structural complexity and low abundance in plants of ICA lead to the unsustainable and high-cost supply from chemical synthesis and plant extraction. Here, the whole biosynthesis pathway of ICA was elucidated, then was constructed in Saccharomyces cerevisiae, including a 13-step heterologous ICA pathway from eleven kinds of plants as well as deletions or overexpression of ten yeast endogenous genes. Spatial regulation of 8-C-prenyltransferase to mitochondria and three-stage sequential control of 4'-O-methyltransferase, 3-OH rhamnosyltransferase, and 7-OH glycosyltransferase expression successfully achieved the de novo synthesis of ICA with a titer of 130 µg/L under shake-flask culture. The ICA synthesis from glucose represents the longest reconstructed pathway of flavonoid in microbe so far. This study provides a potential choice for the sustainable microbial production of number of complex flavonoids.

Metal Cation-Doped ns-Cucurbit[10]uril: Adsorption of Para-Phenylenediamine.

The separation of phenylenediamine (PDA) isomers is crucial in the field of chemical manufacturing. Herein, we presented a strategy for the separation of PDA isomers (para-phenylenediamine, p-PDA; meta-phenylenediamine, m-PDA; ortho-phenylenediamine, o-PDA) using four supramolecular framework materials of ns-cucurbit[10]uril (ns-Q[10]), (1) ns-Q[10](Cd), (2) ns-Q[10](Mn), (3) ns-Q[10](Cu), (4) ns-Q[10](Pb). Our findings indicated that these supramolecular framework materials of ns-Q[10] showed remarkable selectivity for para-phenylenediamine (p-PDA) in p-PDA, m-PDA, and o-PDA mixtures, respectively. The variations in selectivity observed in these four single-crystal structures arose from variations in the thermodynamic stabilities and binding modes of the host-guest complexes. Importantly, the supramolecular framework based on ns-Q[10] exhibited selective accommodation of p-PDA over its isomers. This study highlighted the practical application of ns-Q[10] in effectively separating PDA isomers and demonstrated the potential utility of ns-Q[10] in isolating other organic molecules.

Investigation on absorption cross-section of photosynthetic pigment molecules based on a mechanistic model of the photosynthetic electron flow-light response in C3, C4 species and cyanobacteria grown under various conditions.

Investigation on intrinsic properties of photosynthetic pigment molecules participating in solar energy absorption and excitation, especially their eigen-absorption cross-section (σ ik) and effective absorption cross-section (σ ' ik), is important to understand photosynthesis. Here, we present the development and application of a new method to determine these parameters, based on a mechanistic model of the photosynthetic electron flow-light response. The analysis with our method of a series of previously collected chlorophyll a fluorescence data shows that the absorption cross-section of photosynthetic pigment molecules has different values of approximately 10-21 m2, for several photosynthetic organisms grown under various conditions: (1) the conifer Abies alba Mill., grown under high light or low light; (2) Taxus baccata L., grown under fertilization or non-fertilization conditions; (3) Glycine max L. (Merr.), grown under a CO2 concentration of 400 or 600 µmol CO2 mol-1 in a leaf chamber under shaded conditions; (4) Zea mays L., at temperatures of 30°C or 35°C in a leaf chamber; (5) Osmanthus fragrans Loureiro, with shaded-leaf or sun-leaf; and (6) the cyanobacterium Microcystis aeruginosa FACHB905, grown under two different nitrogen supplies. Our results show that σ ik has the same order of magnitude (approximately 10-21 m2), and σ ' ik for these species decreases with increasing light intensity, demonstrating the operation of a key regulatory mechanism to reduce solar absorption and avoid high light damage. Moreover, compared with other approaches, both σ ik and σ ' ik can be more easily estimated by our method, even under various growth conditions (e.g., different light environment; different CO2, NO2, O2, and O3 concentrations; air temperatures; or water stress), regardless of the type of the sample (e.g., dilute or concentrated cell suspensions or leaves). Our results also show that CO2 concentration and temperature have little effect on σ ik values for G. max and Z. mays. Consequently, our approach provides a powerful tool to investigate light energy absorption of photosynthetic pigment molecules and gives us new information on how plants and cyanobacteria modify their light-harvesting properties under different stress conditions.

Non-destructive detection of single-seed viability in maize using hyperspectral imaging technology and multi-scale 3D convolutional neural network.

The viability of Zea mays seed plays a critical role in determining the yield of corn. Therefore, developing a fast and non-destructive method is essential for rapid and large-scale seed viability detection and is of great significance for agriculture, breeding, and germplasm preservation. In this study, hyperspectral imaging (HSI) technology was used to obtain images and spectral information of maize seeds with different aging stages. To reduce data input and improve model detection speed while obtaining more stable prediction results, successive projections algorithm (SPA) was used to extract key wavelengths that characterize seed viability, then key wavelength images of maize seed were divided into small blocks with 5 pixels ×5 pixels and fed into a multi-scale 3D convolutional neural network (3DCNN) for further optimizing the discrimination possibility of single-seed viability. The final discriminant result of single-seed viability was determined by comprehensively evaluating the result of all small blocks belonging to the same seed with the voting algorithm. The results showed that the multi-scale 3DCNN model achieved an accuracy of 90.67% for the discrimination of single-seed viability on the test set. Furthermore, an effort to reduce labor and avoid the misclassification caused by human subjective factors, a YOLOv7 model and a Mask R-CNN model were constructed respectively for germination judgment and bud length detection in this study, the result showed that mean average precision (mAP) of YOLOv7 model could reach 99.7%, and the determination coefficient of Mask R-CNN model was 0.98. Overall, this study provided a feasible solution for detecting maize seed viability using HSI technology and multi-scale 3DCNN, which was crucial for large-scale screening of viable seeds. This study provided theoretical support for improving planting quality and crop yield.

Usability evaluation of augmented reality visualizations on an optical see-through head-mounted display for assisting machine operations.

This study explores the effect of using different visual information overlays and guiding arrows on a machine operation task with an optical see-through head-mounted display (OST-HMD). Thirty-four participants were recruited in the experiment. The independent variables included visual information mode (text, animation, and mixed text and animation) and the use of guiding arrows (with and without arrows). In addition, gender difference was also an objective of this study. The task performance indicators were determined based on task completion time and error counts as well as subjective measures (system usability scale, NASA task load index, and immersion scale). This study used the mixed analysis of variance design to evaluate the main and interaction effects. The results showed that males performed better when using the mixed text and animation mode. Females performed better when using the text mode. In addition, using the mixed text and animation mode demonstrated the best outcome in system usability scale and NASA task load index. For the use of guiding arrows, the task completion time was reduced and the system usability scale, NASA task load index, and immersion scale showed positive effects.