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Frontiers in Bioscience (Landmark... May 2024Oliver is a unique high-quality natural rubber tree species and rare medicinal tree species in China. The rapid characterization of gene function has been severely...
BACKGROUND
Oliver is a unique high-quality natural rubber tree species and rare medicinal tree species in China. The rapid characterization of gene function has been severely hampered by the limitations of genetic transformation methods and breeding cycles. The polyethylene glycol (PEG)-mediated protoplast transformation system is a multifunctional and rapid tool for the analysis of functional genes , but it has not been established in .
METHODS
In this study, a large number of highly active protoplasts were isolated from the stems of seedlings by enzymatic digestion, and green fluorescent protein expression was facilitated using a PEG-mediated method.
RESULTS
Optimal enzymatic digestion occurred when the enzyme was digested for 10 h in an enzymatic solution containing 2.5% Cellulase R-10 (w/v), 0.6% Macerozyme R-10 (w/v), 2.5% pectinase (w/v), 0.5% hemicellulase (w/v), and 0.6 mol/L mannitol. The active protoplast yield under this condition was 1.13 × 106 protoplasts/g fresh weight, and the protoplast activity was as high as 94.84%.
CONCLUSIONS
This study established the first protoplasm isolation and transient transformation system in hard rubber wood, which lays the foundation for subsequent functional studies of genes to achieve high-throughput analysis, and provides a reference for future gene function studies of medicinal and woody plants.
Topics: Protoplasts; Eucommiaceae; Transfection; Green Fluorescent Proteins; Polyethylene Glycols
PubMed: 38812327
DOI: 10.31083/j.fbl2905187 -
PloS One 2024Computer-aided design (CAD) models can now be directly converted into products and structures. One technique to realize such approach is through Additive Manufacturing...
Computer-aided design (CAD) models can now be directly converted into products and structures. One technique to realize such approach is through Additive Manufacturing (AM). AM is relatively new manufacturing technology in which products are manufactured by layering various materials like rubber, metal, ceramic, composites, and polymers. However, the use of this technology requires consideration of its associated cost to ensure its competitiveness. In this paper, a simplified mathematical cost model is suggested. The model considers the main components of costs. The model formula utilizes expenses related to the pre-processing, main processing, and the post-processing operations. To validate the model, it is tested to estimate the cost of medical implants manufacturing using AM technique. In many cases, medical implants require unique or dedicated design for each patient. Hence cost estimation will help to assess and estimate the required financial resources for such operations. A case study is provided in this paper to estimate the manufacturing cost of a finger's phalanges bone, with metal implant using AM technique. The developed model may be described as Activity Based Costing (ABC). The model is introduced to estimate the cost of parts produced using AM technique. Although the model is developed to suit custom implant manufacturing using AM technique, its use may also be adapted to suit the manufacturing of many other parts and products. The developed model is aiming to achieve several tasks namely assigning cost drivers to each activity, estimating the cost of individual actions, allocating overhead expenses, calculating the overall production cost, and establishing an acceptable selling price. It assists companies in computing the cost of custom implants for customers, enhancing the accuracy of production cost estimates, and ultimately boosting profitability.
Topics: Prostheses and Implants; Computer-Aided Design; Humans; Costs and Cost Analysis; Models, Theoretical; Models, Economic; Prosthesis Design
PubMed: 38809934
DOI: 10.1371/journal.pone.0301440 -
SAGE Open Medical Case Reports 2024We describe the case of a 61-year-old male patient with a history of hemophilia A and previous hepatitis C virus infection with sustained virological response and no...
We describe the case of a 61-year-old male patient with a history of hemophilia A and previous hepatitis C virus infection with sustained virological response and no previous documentation of cirrhosis, who was admitted for variceal bleeding. He was taken for endoscopic evaluation with evidence of active variceal hemorrhage requiring rubber band ligation. Patients with congenital coagulation disorders, such as hemophilia A, are excluded from international guidelines for gastrointestinal bleeding, making their management and counseling challenging. In this article, we describe the specific interventions to be performed in patients with hemophilia A and upper gastrointestinal tract bleeding, specifically variceal bleeding, focusing on pre-endoscopic and endoscopic management.
PubMed: 38800133
DOI: 10.1177/2050313X241255825 -
Clinical Medicine Insights. Case Reports 2024[This corrects the article DOI: 10.1177/11795476231173503.].
[This corrects the article DOI: 10.1177/11795476231173503.].
PubMed: 38800091
DOI: 10.1177/11795476241256213 -
Journal of Applied Glycoscience 2024Water-soluble carbohydrates commonly exist in an amorphous state in foods and undergo glass-rubber transition (glass transition) at the glass transition temperature ()....
Water-soluble carbohydrates commonly exist in an amorphous state in foods and undergo glass-rubber transition (glass transition) at the glass transition temperature (). The critical water content () and critical water activity () are the water content and water activity () at which the glass transition occurs at 298 K (typical ambient temperature), respectively. For amorphous water-soluble carbohydrates, can be predicted from the of anhydrous solid () using previously reported equations. However, an approach for predicting is still lacking. This study aimed to establish an -predictive approach for amorphous water-soluble carbohydrates based on . First, the water sorption isotherms of four hydrogenated starch hydrolysates were investigated, and the results were analyzed using the Guggenheim-Anderson-de Boer (GAB) model. Second, the effect of on the GAB parameters (, , and ) was evaluated using the values reported in previous literatures. and decreased and increased logarithmically, respectively, with increasing 1/. was fixed to 1 (constant), as it showed little variation. These results enabled the prediction of the GAB parameters from . The GAB model could then predict from , which was determined using the previously established equations. The predicted values were in good agreement with the experimentally determined . Additionally, we demonstrated that this -prediction approach is also applicable to amorphous water-soluble electrolytes and partially water-insoluble carbohydrates. Thus, this approach can be used for the quality control of amorphous water-soluble carbohydrates and carbohydrate-based foods.
PubMed: 38799416
DOI: 10.5458/jag.jag.JAG-2023_0015 -
BMC Surgery May 2024As a minimally invasive procedure, laser hemorrhoidoplasty (LHP) can not only relieve the symptoms of hemorrhoids, but also protect the anal cushion structure. This... (Randomized Controlled Trial)
Randomized Controlled Trial Comparative Study
PURPOSE
As a minimally invasive procedure, laser hemorrhoidoplasty (LHP) can not only relieve the symptoms of hemorrhoids, but also protect the anal cushion structure. This study aimed to investigate the clinical efficacy of LHP in the treatment of grade II hemorrhoids.
METHODS
A total of 70 patients with grade II hemorrhoids were randomly assigned to receive LHP or Rubber Band Ligation (RBL) (n = 35 per group) in 2019 from a single center. The postoperative pain, bleeding, feeling of anal distension(local falling, swelling, foreign body sensation, stool) and postoperative recurrence rate were compared between the two groups.
RESULTS
The postoperative pain, bleeding, and feeling of anal distension in the LHP group were improved significantly as compared with the RBL group within 2 weeks after surgery (P < 0.01). Both methods can relieve the symptoms of grade II hemorrhoids. There was no difference in the recurrence rate between the two groups at 1 year after surgery (P > 0.05). The patients in LHP group took less time to return to normal activities (P < 0.001).
CONCLUSIONS
As a minimally invasive treatment, LHP is easy and not traumatic and results in mild postoperative pain and few complications. It is an ideal choice for grade II hemorrhoids.
Topics: Humans; Hemorrhoids; Male; Ligation; Female; Middle Aged; Hemorrhoidectomy; Adult; Laser Therapy; Treatment Outcome; Pain, Postoperative; Minimally Invasive Surgical Procedures; Recurrence
PubMed: 38797851
DOI: 10.1186/s12893-024-02425-z -
Plant Methods May 2024Taraxacum kok-saghyz Rodin (TKS) is a highly potential source of natural rubber (NR) due to its wide range of suitable planting areas, strong adaptability, and...
BACKGROUND
Taraxacum kok-saghyz Rodin (TKS) is a highly potential source of natural rubber (NR) due to its wide range of suitable planting areas, strong adaptability, and suitability for mechanized planting and harvesting. However, current methods for detecting NR content are relatively cumbersome, necessitating the development of a rapid detection model. This study used near-infrared spectroscopy technology to establish a rapid detection model for NR content in TKS root segments and powder samples. The K445 strain at different growth stages within a year and 129 TKS samples hybridized with dandelion were used to obtain their near-infrared spectral data. The rubber content in the root of the samples was detected using the alkaline boiling method. The Monte Carlo sampling method (MCS) was used to filter abnormal data from the root segments of TKS and powder samples, respectively. The SPXY algorithm was used to divide the training set and validation set in a 3:1 ratio. The original spectrum was preprocessed using moving window smoothing (MWS), standard normalized variate (SNV), multiplicative scatter correction (MSC), and first derivative (FD) algorithms. The competitive adaptive reweighted sampling (CARS) algorithm and the corresponding chemical characteristic bands of NR were used to screen the bands. Partial least squares (PLS), random forest (RF), Lightweight gradient augmentation machine (LightGBM), and convolutional neural network (CNN) algorithms were employed to establish a model using the optimal spectral processing method for three different bands: full band, CARS algorithm, and chemical characteristic bands corresponding to NR. The model with the best predictive performance for high rubber content intervals (rubber content > 15%) was identified.
RESULT
The results indicated that the optimal rubber content prediction models for TKS root segments and powder samples were MWS-FD CASR-RF and MWS-FD chemical characteristic band RF, respectively. Their respective , RMSEP, and RPD values were 0.951, 0.979, 1.814, 1.133, 4.498, and 6.845. In the high rubber content range, the model based on the LightGBM algorithm had the best prediction performance, with the RMSEP of the root segments and powder samples being 0.752 and 0.918, respectively.
CONCLUSIONS
This research indicates that dried TKS root powder samples are more appropriate for constructing a rubber content prediction model than segmented samples, and the predictive capability of root powder samples is superior to that of root segmented samples. Especially in the elevated rubber content range, the model formulated using the LightGBM algorithm has superior predictive performance, which could offer a theoretical basis for the rapid detection technology of TKS content in the future.
PubMed: 38797847
DOI: 10.1186/s13007-024-01183-6 -
BMC Oral Health May 2024High speed electric handpieces have recently been growing in popularity among dental professionals. Advantages include smoother surface preparation and increased cutting... (Comparative Study)
Comparative Study
BACKGROUND
High speed electric handpieces have recently been growing in popularity among dental professionals. Advantages include smoother surface preparation and increased cutting efficiency.
AIM
The primary objective was to compare enamel surface roughness following resin cleanup after bracket debonding using highspeed air turbine versus electric handpiece. The secondary objective was to record the time needed for resin-clean up.
METHOD
Forty deidentified freshly extracted human premolars were cleaned and sectioned at the cement-enamel junction. The crowns were embedded in acrylic blocks. Enamel surface roughness parameters (Ra, Rz, Rp and Rv) were measured using a stylus profilometer. Brackets were bonded using a light-cure orthodontic adhesive and stored in distilled water for 24 h. Following bracket debonding, the specimens were randomly divided into 2 groups: First group: resin clean-up was carried out using a 12-fluted carbide bur mounted on a high-speed air turbine; and second group: where an electric handpiece was used. Surface roughness parameters were measured following resin clean up and after polishing using pumice and a rubber cup. Time needed for resin clean-up was recorded. Differences in enamel surface roughness and time between groups were compared using repeated measures ANOVA and independent samples t-test, respectively at P ≤ 0.05.
RESULTS
The electric handpiece groups showed significantly higher values for Ra, Rz and Rp both following resin cleanup and polishing. Time taken for resin cleanup was significantly longer for the electric handpiece group.
CONCLUSION
Considering both surface roughness and time, electric handpiece do not seem to add greater effectiveness or efficiency to resin cleanup following orthodontic bracket debonding.
Topics: Humans; Surface Properties; Dental Debonding; Dental Enamel; Dental High-Speed Equipment; In Vitro Techniques; Resin Cements; Orthodontic Brackets; Time Factors; Bicuspid; Dental Polishing
PubMed: 38796434
DOI: 10.1186/s12903-024-04339-x -
Polymers May 2024Due to their advantages-longer internal force delay compared to bulk materials, resistance to harsh conditions, damping of a wide frequency spectrum, insensitivity to...
Due to their advantages-longer internal force delay compared to bulk materials, resistance to harsh conditions, damping of a wide frequency spectrum, insensitivity to ambient temperature, high reliability and low cost-granular materials are seen as an opportunity for the development of high-performance, lightweight vibration-damping elements (particle dampers). The performance of particle dampers is affected by numerous parameters, such as the base material, the size of the granules, the flowability, the initial prestress, etc. In this work, a series of experiments were performed on specimens with different combinations of influencing parameters. Energy-based design parameters were used to describe the overall vibration-damping performance. The results provided information for a deeper understanding of the dissipation mechanisms and their mutual correlation, as well as the influence of different parameters (base material, granule size and flowability) on the overall damping performance. A comparison of the performance of particle dampers with carbon steel and polyoxymethylene granules and conventional rubber dampers is given. The results show that the damping performance of particle dampers can be up to 4 times higher compared to conventional bulk material-based rubber dampers, even though rubber as a material has better vibration-damping properties than the two granular materials in particle dampers. However, when additional design features such as mass and stiffness are introduced, the results show that the overall performance of particle dampers with polyoxymethylene granules can be up to 3 times higher compared to particle dampers with carbon steel granules and conventional bulk material-based rubber dampers.
PubMed: 38794633
DOI: 10.3390/polym16101440 -
Polymers May 2024Elastomers are made of chain-like molecules to form networks that can sustain large deformation. Rubbers are thermosetting elastomers that are obtained from irreversible... (Review)
Review
Elastomers are made of chain-like molecules to form networks that can sustain large deformation. Rubbers are thermosetting elastomers that are obtained from irreversible curing reactions. Curing reactions create permanent bonds between the molecular chains. On the other hand, thermoplastic elastomers do not need curing reactions. Incorporation of appropriated filler particles, as has been practiced for decades, can significantly enhance mechanical properties of elastomers. However, there are fundamental questions about polymer matrix composites (PMCs) that still elude complete understanding. This is because the macroscopic properties of PMCs depend not only on the overall volume fraction (ϕ) of the filler particles, but also on their spatial distribution (i.e., primary, secondary, and tertiary structure). This work aims at reviewing how the mechanical properties of PMCs are related to the microstructure of filler particles and to the interaction between filler particles and polymer matrices. Overall, soft rubbery matrices dictate the elasticity/hyperelasticity of the PMCs while the reinforcement involves polymer-particle interactions that can significantly influence the mechanical properties of the polymer matrix interface. For ϕ values higher than a threshold, percolation of the filler particles can lead to significant reinforcement. While viscoelastic behavior may be attributed to the soft rubbery component, inelastic behaviors like the Mullins and Payne effects are highly correlated to the microstructures of the polymer matrix and the filler particles, as well as that of the polymer-particle interface. Additionally, the incorporation of specific filler particles within intelligently designed polymer systems has been shown to yield a variety of functional and responsive materials, commonly termed smart materials. We review three types of smart PMCs, i.e., magnetoelastic (M-), shape-memory (SM-), and self-healing (SH-) PMCs, and discuss the constitutive models for these smart materials.
PubMed: 38794580
DOI: 10.3390/polym16101387