Improving synthetic CT accuracy by combining the benefits of multiple normalized preprocesses.

PURPOSE: To investigate the effect of different normalization preprocesses in deep learning on the accuracy of different tissues in synthetic computed tomography (sCT) and to combine their advantages to improve the accuracy of all tissues. METHODS: The cycle-consistent adversarial network (CycleGAN) model was used to generate sCT images from megavolt cone-beam CT (MVCBCT) images. In this study, 2639 head MVCBCT and CT image pairs from 203 patients were collected as a training set, and 249 image pairs from 29 patients were collected as a test set. We normalized the voxel values in images to 0 to 1 or -1 to 1, using two linear and five nonlinear normalization preprocessing methods to obtain seven data sets and compared the accuracy of different tissues in different sCT obtained from training these data. Finally, to combine the advantages of different normalization preprocessing methods, we obtained sCT_Blur by cropping, stitching, and smoothing (OpenCV's cv2.medianBlur, kernel size 5) each group of sCTs and evaluated its image quality and accuracy of OARs. RESULTS: Different normalization preprocesses made sCT more accurate in different tissues. The proposed sCT_Blur took advantage of multiple normalization preprocessing methods, and all tissues are more accurate than the sCT obtained using a single conventional normalization method. Compared with other sCT images, the structural similarity of sCT_Blur versus CT was improved to 0.906 ± 0.019. The mean absolute errors of the CT numbers were reduced to 15.7 ± 4.1 HU, 23.2 ± 7.1 HU, 11.5 ± 4.1 HU, 212.8 ± 104.6 HU, 219.4 ± 35.1 HU, and 268.8 ± 88.8 HU for the oral cavity, parotid, spinal cord, cavity, mandible, and teeth, respectively. CONCLUSION: The proposed approach combined the advantages of several normalization preprocessing methods to improve the accuracy of all tissues in sCT images, which is promising for improving the accuracy of dose calculations based on CBCT images in adaptive radiotherapy.

Automatic segmentation and detection of ectopic eruption of first permanent molars on panoramic radiographs based on nnU-Net.

AIM: The purpose of this research was to present an artificial intelligence (AI) model, which can automatically segment and detect ectopic eruption of first permanent molars (EMMs) in early mixed dentition on panoramic radiographs using the no-new-Net (nnU-Net) model. DESIGN: A total of 438 EMMs obtained from 285 panoramic radiographs were included in this study. An AI model based on nnU-Net was trained to segment and detect EMMs. The performance of the model was evaluated by the intersection over union (IoU), precision, F1-score, accuracy and FROC. Furthermore, the detecting performance of nnU-Net was compared with that of three dentists with different years of experience using the McNemar chi-squared test. The reliability of different dentists was evaluated by intraclass correlation coefficients (ICCs). RESULTS: The nnU-Net yielded an IoU of 0.834, a precision of 0.845, an F1-score of 0.902 and an accuracy of 0.990, whereas the dentists yielded a mean IoU of 0.530, a mean precision of 0.539, a mean F1-score of 0.699 and a mean accuracy of 0.811. The ICC of different dentists was 0.776. The statistical analysis of the McNemar chi-squared test showed that the nnU-Net results were statistically significant and superior to those of dentists (p < .05). CONCLUSION: This study validated an AI model based on nnU-Net for automatically segmenting and detecting EMMs more consistently and accurately on panoramic radiography.

A two-stage deep learning architecture for radiographic staging of periodontal bone loss.

BACKGROUND: Radiographic periodontal bone loss is one of the most important basis for periodontitis staging, with problems such as limited accuracy, inconsistency, and low efficiency in imaging diagnosis. Deep learning network may be a solution to improve the accuracy and efficiency of periodontitis imaging staging diagnosis. This study aims to establish a comprehensive and accurate radiological staging model of periodontal alveolar bone loss based on panoramic images. METHODS: A total of 640 panoramic images were included, and 3 experienced periodontal physicians marked the key points needed to calculate the degree of periodontal alveolar bone loss and the specific location and shape of the alveolar bone loss. A two-stage deep learning architecture based on UNet and YOLO-v4 was proposed to localize the tooth and key points, so that the percentage of periodontal alveolar bone loss was accurately calculated and periodontitis was staged. The ability of the model to recognize these features was evaluated and compared with that of general dental practitioners. RESULTS: The overall classification accuracy of the model was 0.77, and the performance of the model varied for different tooth positions and categories; model classification was generally more accurate than that of general practitioners. CONCLUSIONS: It is feasible to establish deep learning model for assessment and staging radiographic periodontal alveolar bone loss using two-stage architecture based on UNet and YOLO-v4.

Evaluation of autoantibodies and immunoglobulin G subclasses in women with suspected macroprolactinemia.

BACKGROUND: Macroprolactin mostly composed of an immunoglobulin G (IgG) and a monomeric prolactin (PRL) represents the major circulating PRL form in the patients with macroprolactinemia that are usually asymptomatic and may not require treatment. In this study, we aimed to evaluate the prevalence of antithyroid and antinuclear antibodies, as well as the IgG subclass distributions in the patients suspected for macroprolactinemia. METHODS: From January to July in 2018, totally 317 patients with elevated PRL were subjected to the polyethylene glycol (PEG) precipitation assay. The patients with recovery rates of ≤60% were subjected for IgG subclass determination and autoantibody testing including thyroid peroxidase antibody (aTPO), antithyroglobulin antibody (aTG), and antinuclear antibodies (ANA). RESULTS: The higher the post-PEG PRL recovery rates, the less typical hyperprolactinemia symptoms and the higher prevalence of autoantibodies were observed. The IgG1 and IgG3 were the predominant subclasses in the PRL-IgG complexes according to the immunoprecipitation experiments. CONCLUSION: The patients with post-PEG PRL recovery rates of <40% and 40%-60% were likely to represent two distinct populations of different clinical presentations. The prevalence of autoantibodies and IgG subclasses distribution suggested their pathogenic significance in the development of macroprolactinemia.

Tissue adhesive for wound closure in enhanced-recovery total hip arthroplasty: a prospective, randomized and controlled study.

BACKGROUND: We aimed to present our experience of adopting tissue adhesive as adjunct to standard wound closure in total hip arthroplasty (THA) and evaluate its performance. METHODS: From September 2019 to November 2019, we prospectively enrolled consecutive patients who underwent simultaneous bilateral THA in this randomized and controlled study. Standard wound closure was applied on one side of hip while additional tissue adhesive was applied on the other side at random. We collected and analyzed patients' information, including age, gender, body mass index (BMI), diagnosis, postoperative length of stay (LOS), dressing changes, wound evaluation scores, wound-related cost and complications. RESULTS: Thirty patients with simultaneous bilateral THA were enrolled in this study. During the hospital stay, the times of dressing change in hips with tissue adhesive was significantly less than that in the other hips (p = 0.000). However, the wound-related cost in hips with tissue adhesive was significantly higher (p = 0.000). According to patients' feedback at one-month follow-up, wound evaluation of hips with tissue adhesive was significantly better than the other hips (p = 0.004). Seventeen patients preferred tissue adhesive and only five patients preferred standard wound closure. CONCLUSIONS: Tissue adhesive could significantly reduce wound drainage and increase patients' satisfaction, which can be an ideal adjunct to standard wound closure in enhanced-recovery THA. TRIAL REGISTRATION: Chinese Clinical Trial Registry; ChiCTR1900025730; Registered 6 September 2019.

Directional axonal regrowth induced by an aligned fibrin nanofiber hydrogel contributes to improved motor function recovery in canine L2 spinal cord injury.

Spinal cord injuries (SCI) normally disrupt the long axonal tracts of the spinal cord and cause permanent neurological deficits, for which there is currently a lack of effective therapeutic methods. Biomaterial-based regenerative medicine is a pivotal strategy to induce axonal regeneration through delivery of biophysical and/or biochemical regulatory cues by biomaterials. We previously fabricated a hierarchically aligned fibrin hydrogel (AFG) that could promote neurogenic differentiation of stem cells in vitro and has been successfully applied for peripheral nerve and spinal cord regeneration in rats. In this study, AFG was used to repair a canine lumbar segment 2 hemisection spinal cord injury, and the consistency of histological, imageological and behavioral results was compared. AFG was used to construct an aligned fiber bridge that supported cell adhesion in vitro and rapidly facilitated tissue invasion along the long axis of fibers in vivo, Moreover, in vivo results demonstrated regrowth of axons in an oriented pattern connecting the rostral and caudal stumps. Consistent results were confirmed by diffusion tensor imaging, which allowed successful tracing of reconnected nerve fibers across the defect. As a result, directional axonal regrowth contributed to significantly improved recovery of motor functional behavior of SCI canines with AFG implantation. Our results suggest that AFG has great promise for rapidly directing axonal regrowth for nerve regeneration.

Improvement of the chemical recycling process of waste carbon fibre reinforced plastics using a mechanochemical process: Influence of process parameters.

We present the experimental results of an optimal recycling method for waste carbon fibre reinforced plastics (CFRPs) that is based on the application of a set of unit mechanochemical processes. The objectives of this study were to highlight the influence of process factors that are inherent in the chemical recycling process of waste CFRP. We investigated the influence of the soaking period, the application of a catalyst and impurities on the recycling process and recovery efficiency of the waste CFRP. Different combinations of the unit mechanochemical processes were investigated, and the effectiveness of the combination was analysed. The chemical recycling process was conducted using benzyl alcohol under ordinary pressure at initial solvent temperatures lower/equivalent to its flash point temperature. Experimental results showed that the solvent temperature increased up to boiling temperature levels when the mechanochemical process was initiated, thereby enhancing the mechanochemical process. The presence of impurities did not influence the recovery rate. Likewise, this experimental study highlighted the importance of accounting for the soaking period during the chemical recycling process: an extended soaking period resulted in a higher recovery rate, a lower portion of undissolved solids and recovered fibres of better quality. This research highlighted the significance of choosing the proper combination for the chemical recycling process as well as the benefits of recycling the waste CFRP with negligible application of the catalyst.

Replacement of severely traumatized teeth with immediate implants and immediate loading: literature review and case reports.

One of the options for management of severely traumatized dentitions is to provide immediate implant placement with immediate loading. Three representative cases out of 15 patients with 23 traumatized teeth treated to date in our clinic are presented. None had labial bone fractures. The teeth were replaced with NobelReplace Groovy implants (Nobel Biocare, Gothenburg, Sweden) in the fresh sockets immediately after extraction. They were placed toward the palatal areas in the sockets and 3 mm below the gingival margins. If there were gaps between implants and sockets wider than 1 mm, particulate deproteinized bovine bone was grafted in the gaps. Immediately after placement, the implants were loaded with provisional prostheses. The final restorations were installed 3-4 months later. The patients were reevaluated clinically and radiographically 1-3 years after the final restorations had been placed. In all 15 patients, excellent functional and esthetic results were achieved. No implants showed radiolucency, peri-implant suppuration, or mobility. The patients were satisfied with the results. Immediate implant placement with immediate loading is an option that provides good treatment outcomes and allows good functional and esthetic results, as well as addressing the social/psychological aspects of dental trauma.

Possible socioeconomic and oral hygiene behavioural risk factors for self-reported periodontal diseases in women of childbearing age in a Chinese population.

PURPOSE: To examine the socioeconomic and behavioural risk factors for periodontal disease in women of childbearing age and evaluate the extent of public awareness of the association between oral health and pregnancy in China. MATERIALS AND METHODS: Cross-sectional data from 832 women (including 188 pregnant women) from Yuyao, Zhejiang Province were collected using a structured questionnaire. Demographic data were used to measure the participants' socioeconomic status. The questionnaire assessed knowledge and behaviours related to personal oral hygiene and utilisation of dental care services. Data were divided into pregnant and non-pregnant groups for multivariate logistic regression analysis. RESULTS: In total, 88.3% pregnant women and 74.2% non-pregnant women reported periodontal symptoms. Abnormal body mass index (BMI ≤ 18.5, odds ratio, OR = 0.76, 95% CI 0.27-0.97, P = 0.024; BMI ≥ 23.9, OR = 1.83, 95% CI 1.12-3.35, P = 0.035) was significantly associated with self-reported periodontal disease. Minimal mental stress (OR = 0.56, 95% CI 0.43-0.94, P = 0.028), high annual household income (OR = 0.69, 95% CI 0.17-0.82, P = 0.008), advanced oral hygiene aids (OR = 0.33, 95% CI 0.18-0.49, P < 0.001) and knowledge of the link between pregnancy and periodontal disease (OR = 0.57, 95% CI 0.33-0.96, P = 0.016) were associated with decreased incidence of self reported periodontal disease. CONCLUSIONS: A low socioeconomic background was correlated with the high incidence of self-reported periodontal disease among women of childbearing age in China. Education about primary oral health and equitable distribution of dental services might be expected to improve oral health in this specific population.

Effect of fit and self-etching adhesive on fiber post retention in endodontically treated teeth.

BACKGROUND: Fiber post (FP) reinforced restoration was widespread in endodontically treated teeth, of which the retention was closely related to fit and operation process. However, the question whether the fit and self-etching adhesive (SED) affect the success of FP restoration still remained unclear. OBJECTIVE: This research aimed to assess how the fit and self-etching adhesive (SED) impact the pull-out bond strength (BS) of glass fiber-reinforced composite posts from the root canal dentin. METHODS: Eighty lower first premolars underwent simulated endodontic treatment, after which their canals were shaped to accommodate a size three RelyX fiber post (FP) (diameter 1.9 mm). They were then divided into 4 equal groups [Unfit post and no SEA (Group UN), Fit post and no SEA (Group FN), Unfit post with SEA (Group UA) and Fit post with SEA (Group FA)] using two different sized FPs and SEA. Cement thickness was acquired by histological analysis and stereomicroscopy. Each sample was tested for pull-out strength through a universal testing machine. Based on the pull-out test, the failure types were observed and scored by visualizing through a stereomicroscope. RESULTS: Group FA demonstrated significantly greater BS compared to Group UN and Group UA, with Group UN showing a statistically significant difference at p< 0.01 and Group UA at p< 0.05. Main failure types in Group FA were Type II, which illustrated that the cement detachment mainly occurred from the post-cement interface. Therefore, Group FA possessed the STRONGEST BS and was most suitable for FP-reinforced crown restorations. CONCLUSIONS: Both the fit and SEA enhanced the pull-out BS. The SEA was critical for BS promotion when the mechanical retention was inadequate.

Viscoelastic polyacrylamide MR elastography phantoms with tunable damping ratio independent of shear stiffness.

Physiologically modeled test samples with known properties and characteristics, or phantoms, are essential for developing sensitive, repeatable, and accurate quantitative MRI techniques. Magnetic resonance elastography (MRE) is one such technique used to estimate tissue mechanical properties, and it is advantageous to use phantoms with independently tunable mechanical properties to benchmark the accuracy of MRE methods. Phantoms with tunable shear stiffness are commonly used for MRE, but tuning the viscosity or damping ratio has proven to be difficult. A promising candidate for MRE phantoms with tunable damping ratio is polyacrylamide (PAA). While pure PAA has very low attenuation, viscoelastic hydrogels have been made by entrapping linear polyacrylamide strands (LPAA) within the PAA network. In this study, we evaluate the use of LPAA/PAA gels as physiologically accurate phantoms with tunable damping ratio, independent of shear stiffness, via MRE. Phantoms were made with 15.3 wt% PAA while the LPAA concentration ranged from 4.5 wt% to 8.0 wt%. MRE was performed at 9.4 T with 400 Hz vibration on all phantoms revealing a strong, positive correlation between damping ratio and LPAA content (p < 0.001). There was no significant correlation between shear stiffness and LPAA content, confirming a constant PAA concentration yielded constant shear stiffness. Rheometry at 10 Hz was performed to verify the damping ratio of the phantoms. Nearly identical slopes for damping ratio versus LPAA content were found from both MRE and rheometry (0.0073 and 0.0075 respectively). Ultimately, this study validates the adaptation of polyacrylamide gels into physiologically-relevant MRE phantoms to enable testing of MRE estimates of damping ratio.

Facile fabrication of microfibrillated cellulose-based aerogels incorporated with nisin/ß-cyclodextrin microcapsule for channel catfish preservation.

In this study, a hydrophobic and antibacterial pad was prepared to preserve Channel Catfish (Ictalurus punctatus). The pad composite the microfibrillated cellulose and ß-cyclodextrin/nisin microcapsules. The hydrophobic pad ensures a dry surface in contact with the fish, reducing microbial contamination. The pad has a low density and high porosity, making it lightweight and suitable for packaging applications, while also providing a large surface area for antibacterial activity. Results demonstrated that this antibacterial pad exhibits an ultralow density of 9.0 mg/cm3 and an ultrahigh porosity of 99.10%. It can extend the shelf life of Channel Catfish fillets to 9 days at 4 °C, with a total volatile base nitrogen below 20 mg/100 g. The study proposes a novel solution for preserving aquatic products by combining antibacterial substances with the natural base material aerogel. This approach also extends the utilization of aerogel and nisin in food packaging.

Highly efficient and selective removal of anionic dyes from aqueous solutions using polyacrylamide/peach gum polysaccharide/attapulgite composite hydrogels with positively charged hybrid network.

To avoid the weakness (lower adsorption rate and selectivity) of peach gum polysaccharide (PGP) and improve the adsorption performance of polyacrylamide (PAAm) hydrogel (lower adsorption capacity), in the present work, the PGP was chemically tailored to afford ammoniated PGP (APGP) and quaternized PGP (QPGP), and attapulgite (ATP) was bi-functionalized with cation groups and carbon­carbon double bond. Then, PAAm/APGP and PAAm/QPGP/ATP hydrogels were synthesized via redox polymerization. The synthesis procedure and properties of hydrogels were traced by FTIR, SEM, XPS, TGA, TEM, and BET methods, and the dye adsorption performance of the hydrogels was evaluated using the new coccine (NC) and tartrazine (TTZ) aqueous solutions as the model anionic dyes. Effects of initial dye concentration, pH, and ionic strength on the adsorption were investigated. Compared with PAAm/APGP hydrogel, PAAm/APGP/ATP hydrogel exhibits higher adsorption rate, superior adsorption capacity, stability, and selectivity towards anionic dye. The adsorption process of PAAm/QPGP/ATP hydrogel reached equilibrium in about 20 min and followed the pseudo-second-order kinetic model and Langmuir isotherm. The adsorption capacities towards NC and TTZ of PAAm/QPGP/ATP hydrogel were calculated as 873.235 and 731.432 mg/g. This hydrogel adsorbent originating from PAAm, PGP, and ATP shows great promise for application in practical water treatment.

Study of the intentional replantation procedure used to treat a tooth with a palatogingival groove: A case report.

In order to clarify the prognosis of intentional replantation used for palatogingival groove treatment for long-term follow-up observation, the case of a patient with a maxillary lateral incisor with palatogingival groove was investigated. The intentional replantation was carried out to preserve the tooth. The periodontal pocket and the apical bone defect were almost completely repaired at 12-month follow-up. However, the infection was reoccurred after 25-month follow-up examinations. The infected tooth was extracted, of which the root was investigated by histological analysis. Therefore, the reason of the replant failure and the pathways of bacterial infection was investigated. Key words:Palatogingival groove, intentional tooth replantation, bacterial infection, maxillary lateral incisor.

A novel approach for eliminating metal artifacts based on MVCBCT and CycleGAN.

Purpose: To develop a metal artifact reduction (MAR) algorithm and eliminate the adverse effects of metal artifacts on imaging diagnosis and radiotherapy dose calculations. Methods: Cycle-consistent adversarial network (CycleGAN) was used to generate synthetic CT (sCT) images from megavoltage cone beam CT (MVCBCT) images. In this study, there were 140 head cases with paired CT and MVCBCT images, from which 97 metal-free cases were used for training. Based on the trained model, metal-free sCT (sCT_MF) images and metal-containing sCT (sCT_M) images were generated from the MVCBCT images of 29 metal-free cases and 14 metal cases, respectively. Then, the sCT_MF and sCT_M images were quantitatively evaluated for imaging and dosimetry accuracy. Results: The structural similarity (SSIM) index of the sCT_MF and metal-free CT (CT_MF) images were 0.9484, and the peak signal-to-noise ratio (PSNR) was 31.4 dB. Compared with the CT images, the sCT_MF images had similar relative electron density (RED) and dose distribution, and their gamma pass rate (1 mm/1%) reached 97.99% ± 1.14%. The sCT_M images had high tissue resolution with no metal artifacts, and the RED distribution accuracy in the range of 1.003 to 1.056 was improved significantly. The RED and dose corrections were most significant for the planning target volume (PTV), mandible and oral cavity. The maximum correction of Dmean and D50 for the oral cavity reached 90 cGy. Conclusions: Accurate sCT_M images were generated from MVCBCT images based on CycleGAN, which eliminated the metal artifacts in clinical images completely and corrected the RED and dose distributions accurately for clinical application.

CariesNet: a deep learning approach for segmentation of multi-stage caries lesion from oral panoramic X-ray image.

Dental caries has been a common health issue throughout the world, which can even lead to dental pulp and root apical inflammation eventually. Timely and effective treatment of dental caries is vital for patients to reduce pain. Traditional caries disease diagnosis methods like naked-eye detection and panoramic radiograph examinations rely on experienced doctors, which may cause misdiagnosis and high time-consuming. To this end, we propose a novel deep learning architecture called CariesNet to delineate different caries degrees from panoramic radiographs. We firstly collect a high-quality panoramic radiograph dataset with 3127 well-delineated caries lesions, including shallow caries, moderate caries, and deep caries. Then we construct CariesNet as a U-shape network with the additional full-scale axial attention module to segment these three caries types from the oral panoramic images. Moreover, we test the segmentation performance between CariesNet and other baseline methods. Experiments show that our method can achieve a mean 93.64% Dice coefficient and 93.61% accuracy in the segmentation of three different levels of caries.

Effects of different cross-linking conditions on the properties of genipin-cross-linked chitosan/collagen scaffolds for cartilage tissue engineering.

A cross-linking reagent is required to improve mechanical strength and degradation properties of biopolymers for tissue engineering. To find the optimal preparative method, we prepared diverse genipin-cross-linked chitosan/collagen scaffolds using different genipin concentrations and various cross-linking temperatures and cross-linking times. The compressive strength increased with the increasing of genipin concentration from 0.1 to 1.0%, but when concentration exceeded 1.0%, the compressive strength decreased. Similarly, the compressive strength increased with the increasing of temperature from 4 to 20°C, but when temperature reached 37°C, the compressive strength decreased. Showing a different trend from the above two factors, the effect of cross-linking time on the compressive strength had a single increasing tendency. The other results also demonstrated that the pore size, degradation rate and swelling ratio changed significantly with different cross-linking conditions. Based on our study, 1.0% genipin concentration, 20°C cross-linking temperature and longer cross-linking time are recommended.

Changes in Maxillary Sinus Mucosal Thickening following the Extraction of Teeth with Advanced Periodontal Disease: A Retrospective Study Using Cone-Beam Computed Tomography.

OBJECTIVES: To explore the alterations in maxillary sinus mucosal thickening after extracting teeth with severe periodontal disease using cone-beam computed tomography (CBCT). METHODS: 30 patients with severe periodontal disease of maxillary posterior teeth that needed to be extracted and who were radiographically diagnosed with mucosal thickening (MT) in the maxillary sinus participated in the study. CBCT scans were taken before tooth extraction and 2-29 months after tooth extraction. The postextraction follow-up time was divided into two groups: group 1 (<4 months) and group 2 (≥4 months). Dimensions of maxillary sinus MT, including the MT zone length (SL) and the maximum thickness of the MT zone (ST), were evaluated preextraction and postextraction; the residual ridge height (RRH) was evaluated at the sites of extracted and nonextracted teeth. RESULT: Of the 24 patients with unilateral tooth extraction, there was a statistically significant difference in MT between the extraction and nonextraction sides (p < 0.05). The RRH at the site of the extracted teeth was significantly lower than that of the nonextracted teeth (p < 0.05). MT decreased significantly after tooth extraction on the extraction side but not on the nonextraction side. There was no significant difference between group 1 and group 2 regarding the reduction in mucosal thickness over time. CONCLUSIONS: Severe periodontitis can cause MT in the maxillary sinus. The RRH was lower at the sites of extracted teeth. MT reduced quickly by a thorough debridement after tooth extraction in 4 months. MT will not decrease further over time.

Effects of simulated saliva-gastrointestinal digestion on the physicochemical properties and bioactivities of okra polysaccharides.

This study was to investigate the effects of in vitro simulated saliva-gastrointestinal digestion on the physicochemical properties and bioactivities of okra polysaccharides (OPS). Results showed that the digestibilities of OPS were about 5.1%, 37.5%, and 41.3% after saliva digestion (SD), saliva-gastric digestion (SGD), and saliva-gastrointestinal digestion (SGID), respectively. The SGID significantly changed the physicochemical properties of OPS, such as total uronic acids, total flavonoids, monosaccharide composition, rheological properties, and molecular weights (Mw). Especially, Mw changes resulted in the breakdown of glycosidic bonds during SGD, and the degradation of OPS during SGID was mainly caused by disrupting aggregates. Furthermore, the bioactivities of OPS were also affected by SGID. After SGID, OPS still possessed strong antioxidant activities, binding capacities, and prebiotic activities, but the α-glucosidase inhibitory effect was obviously decreased. Overall, results can provide valuable and scientific support on the oral administration of OPS as functional foods and medicines in the future.

Nanolayer coextrusion: An efficient and environmentally friendly micro/nanofiber fabrication technique.

Researchers have developed many types of nanoscale materials with different properties. Among them, nanofibers have recently attracted increasing interest and attention due to their functional versatility and potential applications in diverse industries, including tapes, filtration, energy generation, and biomedical technologies. Nanolayer coextrusion, a novel polymer melt fiber processing technology, has gradually received attention due to its environmental friendliness, efficiency, simplicity and ability to be mass-produced. Compared with conventional techniques, nanolayer coextruded non-woven nanofibrous mats offer advantages such as a tunable fiber diameter, high porosity, high surface area to volume ratio, and the potential to manufacture composite nanofibers with different components to achieve desired structures and properties. Dozens of thermoplastic polymers have been coextruded for various applications, and the variety of polymers has gradually continued to increase. This review presents an overview of the nanolayer coextrusion technique and its promising advantages and potential applications. We discuss nanolayer coextrusion theory and the parameters (polymer and processing) that significantly affect the fiber morphology and properties. We focus on varied applications of nanolayer coextruded fibers in different fields and conclude by describing the future potential of this novel technology.