Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 7.475
Filtrar
1.
Clin Oral Investig ; 28(10): 571, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365479

RESUMEN

OBJECTIVES: Single midline implants in the edentulous mandible can be used to support existing complete dentures to improve patients' satisfaction and masticatory efficiency. The impact on patients' dietary habits and the influence of the loading protocol of the implants was the subject of this study. MATERIALS AND METHODS: In this prospective randomized clinical trial, edentulous patients with existing complete dentures in both jaws were treated with a single midline implant in the mandible. In group A, the implants were loaded immediately, in group B the loading was delayed after three months. Patients were asked to report on their nutritional intake before implant placement and 12, 24 and 60 months after loading using a standardized two-part questionnaire. RESULTS: Nutritional intake regarding the frequency of consumption of the requested food items did not change significantly during the 60-months study period, regardless of the loading protocol. In contrast, the second part of the questionnaire revealed that after 60 months, there was a significant decrease in avoidance of food, that had a coarse and hard texture in both groups. This significant decrease was observable in the group A in the first 12 and 24 months and in the group B after 60 months. CONCLUSION: A change in the patients' dietary habits due to the insertion of a single midline implant in the mandible to support the existing complete denture cannot be observed, independently to the loading protocol. CLINICAL RELEVANCE: Improving the chewing efficiency by single midline implants in the edentulous mandible does not lead to a change in dietary habits.


Asunto(s)
Prótesis Dental de Soporte Implantado , Conducta Alimentaria , Carga Inmediata del Implante Dental , Arcada Edéntula , Mandíbula , Humanos , Femenino , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Anciano , Mandíbula/cirugía , Arcada Edéntula/rehabilitación , Masticación/fisiología , Persona de Mediana Edad , Resultado del Tratamiento , Satisfacción del Paciente , Implantes Dentales de Diente Único
2.
Sci Rep ; 14(1): 23260, 2024 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-39370444

RESUMEN

Mortars will remain critical in future land wars due to their flexibility and versatility. When mortars are fired continuously, the contact soil is gradually compacted by the mortar base plate, and dynamic research into this process is the basis for innovative mortar design. However, the discontinuity and nonlinearity of soil contact absolutely necessitate the constitutive relationship of soil contact, which is difficult to study. Therefore, this study conducted experimental research and theoretical derivation to establish an accurate dynamic model of the mortar system. First, based on the nonlinear elastic-plastic theory and the stress-strain relationship of soil under cyclic loading, a theoretical analysis method for the constitutive relationship of contact soil under continuous loading was proposed. Second, an experimental and testing system was designed to simulate launch loads, and the stress-strain response of soil under continuous impact loads was obtained experimentally. Subsequently, based on theoretical analysis and experimental data, the stress-strain relationship during the gradual compaction of soil was established using the least squares method. Finally, a constitutive relationship model of the contact soil in the mortar system was established in ABAQUS using the VUMAT subroutine interface, and the calculated results were compared and analyzed with traditional calculation results. The results indicated that studying the constitutive relationship of mortar in contact with soil during continuous firing using this method can improve the accuracy of dynamically modeling mortar systems. Moreover, this study has practical value in the engineering design of mortar systems.

3.
Cureus ; 16(9): e68633, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39371842

RESUMEN

Polymers can be crosslinked chemically or physically to create three-dimensional hydrogel particles with sub-micron dimensions, known as nanogels. Their customizable size, ease of manufacture, expansion potential, bio-integration, water affinity, and reactivity to various stimuli, including temperature, pH, light, and biological agents, provide them with considerable advantages over conventional drug delivery techniques. Nanogels possess properties of both hydrogels and nanoparticles and can be categorized into nanohydrogels and nano-organogels. These systems exhibit exceptional drug-loading capability, stability, biological consistency, and environmental responsiveness. Their hallmark lies in their swelling behavior, enabling substantial water absorption while maintaining structural integrity. Preparation methods involve polymer precursors or heterogeneous polymerization of monomers. Nanogels are promising for various drug administration techniques, including local anesthetics, vaccines, and transdermal drug delivery, due to their ability to encapsulate multiple bioactive ingredients, enhancing therapeutic efficacy and stability.

4.
ACS Nano ; 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39374417

RESUMEN

Silver nanoparticles (AgNPs) are widely used as nanoagents in biomedical fields, while it is still challenging to improve their loading capacity and biocompatibility in microcarrier delivering systems. Herein, the physicochemical properties of AgNPs were manipulated by forming biomolecular corona derived from bovine serum albumin (AC), and three organisms at various trophic levels: Chlorella sp. (BC1), Daphnia magna (BC2), and zebrafish (BC3). Proteins were identified by chemical composition analysis as the dominant components adsorbed on the surface of AgNPs. Proteomics indicated that AgNPs preferred to bind with low molecular weight (<50 kDa) and hydrophobic proteins with more positively charged residues. Consequently, AC and BC3 displayed stronger adsorption affinity on the surface of AgNPs than BC1 and BC2. Modifications by AC and BC3 effectively alleviated the oxidative stress and cell cycle arrest of AgNPs due to their superior antioxidative ability. However, BC3 with lower hydrophobicity enabled AgNPs to be more biocompatible than AC at subcellular level. Moreover, AC could significantly improve the loading capacity of AgNPs by Chlorella through enhancing caveolin-mediated endocytosis. Notably, owing to the adsorption of abundant Ca2+-binding proteins, BC3-AgNPs could also be internalized by microalgae via Ca2+-dependent clathrin-mediated endocytosis, which makes it a promising approach to deliver AgNPs. The results of this study would provide insights into the development of an efficient strategy to deliver AgNPs based on the microalgae carrier without altering its original properties and functionality.

5.
ACS Nano ; 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367859

RESUMEN

We report a design for a synergistic lithium (Li) metal hosting layer for high-loading Li(Ni,Co,Al)O2 (NCA) (≥5 mA h cm-2)||Li-metal full cells in carbonate electrolytes. Based on density functional theory calculations, the hosting layer was designed as a three-dimensional silver/carbon composite nanofiber (Ag/CNF) network with high Li affinity and a platinum (Pt)-coated polypropylene separator with low Li affinity. This design enabled the tailoring of horizontal Li deposition on the Ag/CNF hosting layer. The Li deposition behavior modulated by the hosting layer was thoroughly examined based on the initial Li deposition and cycling behaviors of the Li||Li symmetric cell configuration. Cryogenic focused-ion beam cross-sectional images of the cycled Li anodes clearly demonstrated that dense lithium deposition was enabled by the synergistic hosting layer high-loading NCA (≥5 mA h cm-2)||Li-metal full cells. When the hosting layer was used, the average cycling performance improved by 78.27% under various cycling conditions. Our work demonstrates that the synergistic hosting layer design is a fruitful pathway to accelerate the commercialization of high-energy-density Li-metal batteries in carbonate electrolytes.

6.
Exp Brain Res ; 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377918

RESUMEN

To investigate differences in proprioception using four proprioceptive tests in children with and without hypermobility. Additionally, it was tested if the results on one proprioceptive test predict the results on the other tests. Of the children (8-11years), 100 were classified as normal mobile (Beighton score 0-4) and 50 as hypermobile (Beighton score 5-9). To test proprioception, in the upper extremity the unilateral and bilateral joint position reproduction tasks were used and for the lower extremity the loaded and unloaded wedges task. No differences were found in any of the proprioception tests between the two groups. Estimating the height of the wedges was easier in the loaded position (mean penalty in standing and sitting position, 4.78 and 6.19, respectively). Recalling the elbow position in the same arm resulted in smaller errors compared to tasks reproducing the position with the contralateral arm. Of the four angles used (110°, 90°, 70°, 50°), the position recall in the 90° angle had the smallest position error (1.8°). Correlations between the proprioception tests were weak (Loaded and Unloaded (r 0. 28); Uni and Bilateral (r 0.39), Upper and Lower extremity not significant). No indication of poorer proprioception was found in children with hypermobile joints compared to their normal mobile peers. Loading gives extra information that leads to fewer errors in the wedges task performed while standing, but this effect is independent of joint mobility. Proprioception test outcomes are dependent on the test used; upper extremity results do not predict lower extremity outcomes or vice versa.

7.
Nanomicro Lett ; 17(1): 32, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39363132

RESUMEN

The current single-atom catalysts (SACs) for medicine still suffer from the limited active site density. Here, we develop a synthetic method capable of increasing both the metal loading and mass-specific activity of SACs by exchanging zinc with iron. The constructed iron SACs (h3-FNC) with a high metal loading of 6.27 wt% and an optimized adjacent Fe distance of ~ 4 Å exhibit excellent oxidase-like catalytic performance without significant activity decay after being stored for six months and promising antibacterial effects. Attractively, a "density effect" has been found at a high-enough metal doping amount, at which individual active sites become close enough to interact with each other and alter the electronic structure, resulting in significantly boosted intrinsic activity of single-atomic iron sites in h3-FNCs by 2.3 times compared to low- and medium-loading SACs. Consequently, the overall catalytic activity of h3-FNC is highly improved, with mass activity and metal mass-specific activity that are, respectively, 66 and 315 times higher than those of commercial Pt/C. In addition, h3-FNCs demonstrate efficiently enhanced capability in catalyzing oxygen reduction into superoxide anion (O2·-) and glutathione (GSH) depletion. Both in vitro and in vivo assays demonstrate the superior antibacterial efficacy of h3-FNCs in promoting wound healing. This work presents an intriguing activity-enhancement effect in catalysts and exhibits impressive therapeutic efficacy in combating bacterial infections.

8.
Int J Oral Maxillofac Implants ; 0(0): 1-31, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365910

RESUMEN

PURPOSE: Implant-supported overdentures have been an effective treatment method for edentulous mandibles. However, the loading time after implant placement is still controversial. The purpose of this study was to evaluate the outcome of implant-supported overdentures using telescopic crowns for the treatment of edentulous patients with immediate loading protocol. MATERIALS AND METHODS: This study was conducted on 22 edentulous mandibular patients visiting the Department of High Technique, National Hospital of Odonto - Stomatology, Ho Chi Minh City, Vietnam for prosthodontic rehabilitation. Each patient received four interforaminal implants. Immediate loading protocol was applied, and Ankylos Syncone copings systems was used to connect the prosthesis and the implants. The survival rate of implants and prostheses, as the primary outcome, were evaluated at 6 months, 01 year, and 02 years post-surgery. Peri-implant tissue condition, peri-implant bone loss, and patient satisfaction were the secondary outcomes. RESULTS: The implant survival rate was 98.9% with 01 failed implant. The peri-implant bone loss changes after 6 months, 01 year, and 02 years were 0.07 ± 0.22 mm, 0.12 ± 0.3 mm, and 0.15 ± 0.2 mm, respectively. No gingival hyperplasia was recorded. The prosthesis survival rate was 86.4% with 1 fractured overdenture, 1 overdenture relining and 1 abutment fracture. CONCLUSIONS: Mandibular rehabilitation using implant-supported overdenture with telescopic crowns and immediate loading protocol showed high survival rates of both implant and prosthesis in 2-year follow-up.

9.
S Afr J Sports Med ; 36(1): v36i1a16929, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39355556

RESUMEN

Background: The countermovement jump (CMJ) is an integral part of force and velocity profiling; a movement that is regularly implemented in training protocols and testing of athletic performance. Adding external loads to CMJs may have an added benefit for assessing gains in power and, in turn, monitoring progressive development. However, these added loads can displace the centre of mass of individuals, which may alter jump kinetics. Objectives: The study aimed to evaluate kinetics across various incremental modes of loading (barbell, trapezius barbell, and dumbbell) CMJs. Methods: Thirty-two male athletes (age: 19±2 years; height: 1.86±0.06 m, mass: 90.4±5.3 kg) completed three weighted CMJs (20, 40, 60 kg) across three bar-type modes of loading (barbell, trapezius barbell, and dumbbell). Jump metrics were measured using a wearable accelerometer. A repeated measures ANOVA was used to compare jump metrics (p<0.05). Results: The results indicated changes in jump kinetics as added loads increased across all bar-type jump modes (p<0.001). Additionally, jump modes yielded different jump kinetics (p<0.001). Specifically, dumbbell CMJs produced the greatest force (2559 ± 462 N) and power (4861±1632 W) outputs. In contrast, the trapezius barbell consistently produced significantly (p<0.001) higher velocity (2.52±0.44 m.s-1) and acceleration (12.59±4.49 m.s-2), with the barbell never producing the highest kinetic metrics. The athletes' ranges of movement and comfort loading levels during the CMJs may be influential factors affecting vertical jump output metrics. Conclusion: Overall, jump kinetics were altered by loads and jump types. Practically, different loading methods may target distinct jump variables allowing for individualised training programs specific for the athletes' needs.

10.
J Mech Behav Biomed Mater ; 160: 106753, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39369619

RESUMEN

Soft biological polymers, such as articular cartilage, possess exceptional fracture and fatigue resistance, offering inspiration for the development of novel materials. However, we lack a detailed understanding of changes in cartilage material behavior and of crack propagation following cyclic compressive loading. We investigated the structure and mechanical behavior of cartilage as a function of loading frequency and number of cycles. Microcracks were initiated in cartilage samples using microindentation, then cracks were extended under cyclic compression. Thickness, apparent stiffness, energy dissipation, phase angle, and crack length were measured to determine the effects of cyclic loading at two frequencies (1 Hz and 5 Hz). To capture the fatigue-induced material response (thickness, stiffness, energy dissipation, and phase angle), material properties were compared between pre-and-post diagnostic tests. The findings indicate that irreversible structural damage (reduced thickness), cartilage softening (reduced apparent stiffness), and reduced energy dissipation (including phase angle) increased with an increase in the number of cycles. Higher frequency loading resulted in less reduction in energy dissipation, phase angle, and thickness change. Crack lengths, quantified through brightfield imaging, increased with number of cycles and frequency. This study sheds light on the complex response of cartilage under cyclic loading resulting in softening, structural damage, and altered dynamic behavior. The findings provide better understanding of failure mechanisms in cartilage and thus may help in diagnosis and treatment of osteoarthritis.

11.
J Cell Physiol ; : e31451, 2024 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-39358905

RESUMEN

Cancer stem cells (CSCs) are considered the major cause of the occurrence, progression, chemoresistance/radioresistance, recurrence, and metastasis of cancer. Increased interstitial fluid pressure (IFP) is a key feature of solid tumors. Our previous study showed that the distribution of liver cancer stem cells (LCSCs) correlated with the mechanical heterogeneity within liver cancer tissues. However, the regulation of liver cancer's mechanical microenvironment on the LCSC stemness is not fully understood. Here, we employed a cellular pressure-loading device to investigate the effects of normal IFP (5 mmHg), as well as increased IFP (40 and 200 mmHg) on the stemness of LCSCs. Compared to the control LCSCs (exposure to 5 mmHg pressure loading), the LCSCs exposed to 40 mmHg pressure loading exhibited significantly upregulated expression of CSC markers (CD44, EpCAM, Nanog), enhanced sphere and colony formation capacities, and tumorigenic potential, whereas continuously increased pressure to 200 mmHg suppressed the LCSC characteristics. Mechanistically, pressure loading regulated Yes-associated protein (YAP) activity and Bcl-2 modifying factor (BMF) expression. YAP transcriptionally regulated BMF expression to affect the stemness of LCSCs. Knockdown of YAP and overexpression of BMF attenuated pressure-mediated stemness and tumorgenicity, while YAP-deficient and BMF-deletion recused pressure-dependent stemness on LCSCs, suggesting the involvement of YAP/BMF signaling axis in this process. Together, our findings provide a potential target for overcoming the stemness of CSCs and elucidate the significance of increased IFP in cancer progression.

12.
Sci Rep ; 14(1): 21103, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256505

RESUMEN

Since accidents such as roof caving, rock fragmentation, and severe deformation are particularly likely to occur during roadway excavation in soft and thick coal seams, grasping the range and distribution of deformation and fracturing of surrounding rock is of crucial for evaluating roadway stability and optimizing support design in such coal seams. In this study, based on the stress paths encountered during roadway excavation, true triaxial loading and unloading tests were carried out on soft coal, and the deformation and strength evolutions of soft coal under different intermediate principal stress conditions were analyzed. The test results show that the stress-strain relationship in the pre-peak plasticity-strengthening and post-peak plasticity-weakening stages follows a quadratic function, and the strengeth evolution conforms to the Mogi-Coulomb criterion. Moreover, analytical solutions for the displacement of surrounding rock, the radius of the broken zone, and the radius of the plastic zone of soft-coal roadways under excavation stress paths were derived after taking the nonlinear hardening and softening characteristics of the strain of soft coal, the Mogi-Coulomb criterion, the intermediate principal stress, and the dilatancy characteristics of surrounding rock into comprehensive consideration. Finally, in accordance with a practical engineering case, the influences of the intermediate principal stress coefficient, the lateral pressure coefficient, and the support force on the deformation and failure characteristics of the soft-coal roadway were analyzed. The analysis reveals that an increase in intermediate principal stress aggravates the deformation of surrounding rock and enlarges the plastic and broken zones; variations in the lateral pressure coefficient alter the shape of the broken zone and the distribution of surface displacement; and an increase in the support force effectively reduces the plastic zone, broken zone, and surface displacement of the roadway. The research results can provide valuable theoretical basis for the stability evaluation and support design of soft-coal roadways.

13.
J Clin Med ; 13(17)2024 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-39274234

RESUMEN

Background/Objectives: Hip mobility and joint loading in hip osteoarthritis (HOA) patients are mostly assessed during straight walking. Yet, mobility limitations in the frontal and transverse planes are rarely found during this task in subjects with mild-to-moderate symptoms. Turning movements are frequently encountered during everyday life and might require larger hip mobility compared to straight walking, especially in the frontal and transverse planes. Thus, hip mobility and hip loading during straight walking and 90° turns in persons with HOA and healthy older adults were compared in this study. Methods: A retrospective analysis was conducted on 21 subjects with mild-to-moderate HOA and 21 healthy controls. Hip angles and moments were assessed during straight walking and 90° step and spin turns. Gait analysis was conducted using a motion capture system and a force plate. Group and movement task differences were assessed with a mixed-model ANOVA. Results: Peak abduction and adduction angles were largest during the step and spin turn, respectively, as were the group differences between HOA subjects and healthy subjects. Both turns require a greater transverse hip range of motion compared to straight walking. Limitations in transverse hip mobility in the HOA group were especially prominent during the step turn. Both turns cause higher joint moments than straight walking. Conclusions: The additional inclusion of 90° step and spin turns into gait analysis can enhance early identification of hip mobility limitations in the frontal and transverse planes in subjects with mild-to-moderate hip osteoarthritis. Early diagnosis is crucial for the timely application of conservative treatment strategies.

14.
Materials (Basel) ; 17(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39274671

RESUMEN

The aim of the work presented in this paper was development of a thermodynamically consistent constitutive model for orthotopic metals and determination of its parameters based on standard characterisation methods used in the aerospace industry. The model was derived with additive decomposition of the strain tensor and consisted of an elastic part, derived from Helmholtz free energy, Hill's thermodynamic potential, which controls evolution of plastic deformation, and damage orthotopic potential, which controls evolution of damage in material. Damage effects were incorporated using the continuum damage mechanics approach, with the effective stress and energy equivalence principle. Material characterisation and derivation of model parameters was conducted with standard specimens with a uniform cross-section, although a number of tests with non-uniform cross-sections were also conducted here. The tests were designed to assess the extent of damage in material over a range of plastic deformation values, where displacement was measured locally using digital image correlation. The new model was implemented as a user material subroutine in Abaqus and verified and validated against the experimental results for aerospace-grade aluminium alloy 2024-T3. Verification was conducted in a series of single element tests, designed to separately validate elasticity, plasticity and damage-related parts of the model. Validation at this stage of the development was based on comparison of the numerical results with experimental data obtained in the quasistatic characterisation tests, which illustrated the ability of the modelling approach to predict experimentally observed behaviour. A validated user material subroutine allows for efficient simulation-led design improvements of aluminium components, such as stiffened panels and the other thin-wall structures used in the aerospace industry.

15.
Molecules ; 29(17)2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39274893

RESUMEN

Ferritin (Ft) is a protein with a peculiar three-dimensional architecture. It is characterized by a hollow cage structure and is responsible for iron storage and detoxification in almost all living organisms. It has attracted the interest of the scientific community thanks to its appealing features, such as its nano size, thermal and pH stability, ease of functionalization, and low cost for large-scale production. Together with high storage capacity, these properties qualify Ft as a promising nanocarrier for the development of delivery systems for numerous types of biologically active molecules. In this paper, we introduce the basic structural and functional aspects of the protein, and summarize the methods employed to load bioactive molecules within the ferritin nanocage.


Asunto(s)
Ferritinas , Nanopartículas , Ferritinas/química , Nanopartículas/química , Humanos , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Animales
16.
J Exp Biol ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39284689

RESUMEN

Flight behaviours of birds have been extensively studied from different angles such as their kinematics, aerodynamics and more general, their migration patterns. Nevertheless, much is still unknown about the daily foraging flight activity and behaviour of breeding birds, and potential differences among males and females. The recent development of miniaturized accelerometers allows us a glimpse into the daily life of a songbird. Here, we tagged 13 male and 13 female pied flycatchers (Ficedula hypoleuca) with accelerometers and used machine learning approaches to analyse their flight activity and effort during the chick rearing period. We found that during two hours of foraging, chick-rearing pied flycatchers were flying on average 13.7% of the time. Almost all flights (>99%) were short flights lasting less than 10s. Flight activity changed throughout the day and was highest in the morning and lowest in the early afternoon. Male pied flycatcher had lower wing loading than females, and in-flight accelerations were inversely correlated with wing loading. Despite this, we found no significant differences in flight duration and intensity between sexes. This suggests that males possess a higher potential flight performance, which they did not fully utilize during foraging flights.

17.
J Mech Behav Biomed Mater ; 160: 106741, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39276437

RESUMEN

Transcatheter aortic valve replacement (TAVR) has become today the most attractive procedure to relieve patients from aortic valve disease. However, the procedure requires crimping biological tissue within a metallic stent for low diameter catheter insertion purpose. This step induces specific stress in the leaflets especially when the crimping diameter is small. One concern about crimping is the potential degradations undergone by the biological tissue, which may limit the durability of the valve once implanted. The purpose of the present work is to investigate the mechanical damage undergone by bovine pericardium tissue during compression and analyze how this degradation evolves with time under fatigue testing conditions. Pericardium 500 µm thick pericardium ribbons (5 mm large, 70 mm long) were crimped down to 12 Fr for 30 and 50 min within a metallic stent to replicate the heart valve crimping configuration. After crimping, samples underwent cyclic fatigue flexure and pressure loading over 0.5 Mio cycles. Samples were characterized for mechanical performances before crimping, after crimping and after fatigue testing in order to assess potential changes in the mechanical properties of the tissue after each step. Results bring out that the ultimate tensile strength is not modified through the process. However an increase in the modulus shows that the crimping step tends to stiffen the pericardium. This may have an influence on the lifetime of the implant.

18.
Food Chem ; 463(Pt 2): 141176, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39276539

RESUMEN

To select an efficient carrier for loading and sustainedly releasing naringin (NAR), complexes of porous starch (PS) and NAR (PS-NAR) as well as those of octenyl succinic anhydride (OSA) esterified PS and NAR (OSAPS-NAR) with different degree of substitution (DS) were prepared by an ultrasonic method with an ethanol solution. The micro-morphological features, structural and thermal properties of complexes and their constituents were characterized, and in vitro release rate and kinetic of NAR from complexes were investigated. The findings revealed that NAR was successfully loaded in PS/OSAPS in an amorphous form, and the NAR's loading efficiency improved as DS increased, reaching 86.85 % at DS 0.0427. NAR cumulative release rate from the complexes in simulated digestion fluids was much higher than that of free (unloaded) NAR, but decreased as DS increased. NAR's in vitro release from complexes mainly depended on the carrier rather than NAR itself, and OSAPS with higher DS had stronger protection and slower release effect on NAR. The results would provide a new means for starch-based carrier construction to develop an efficient delivery and sustainedly releasing system for NAR, thus broadening the application ranges both for modified starch and citrus flavonoids such as NAR.

19.
J Colloid Interface Sci ; 678(Pt C): 57-65, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39277953

RESUMEN

Dry processing emerges as a cost-effective technique for achieving high material loading in the field of lithium-ion battery fabrication. Nevertheless, insight into the role of current collectors in this process is still scarce. Herein, a set of dry-processed electrodes with three different current collectors is accordingly prepared and comprehensively studied. This work novelly reveals that the current collectors exhibit significant influence on the interface adhesion strength and the electron conductivity, which leads to difference in the mechanical strength and electrochemical performance of dry-processed electrodes. Consequently, it is recommended that carbon-coated current collector is preferred for dry-processed high energy density lithium-ion battery electrodes.

20.
Heliyon ; 10(16): e36138, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39229519

RESUMEN

Xylotrechus arvicola Olivier 1795 (Coleoptera: Cerambycidae) is an insect pest that affects Vitis vinifera L. 1753 (Vitales: Vitaceae) plants in the main wine-producing regions of Spain. X. arvicola larvae bore into grapevine wood, causing both direct damage (ingestion of vascular tissues) and indirect damages (introduction of wood fungi) to the plant. The aim of research was to evaluate the effective section of wood damaged by larvae and assess its resistance capacity through compression tests and loading and breaking times. Compressive tests (on trunks) and flexural tests (on branches) were performed to evaluate the effective section. Trunk samples exhibited a higher effective section than branches samples, with effective section percentages ranging from 91.49 % to 93.53 % in trunks and decreasing from 84.91 % to 86.95 % in branches. Both loading times (Time 1) and breakage times (Time 2) increased with the effective section of the wood, although these times were lower in damaged wood samples of both trunks and branches. Additionally, significant differences were observed in the interactions between loading time x effective section and breakage time x effective section in dry trunks. This indicates a stronger relationship between the effective section and increased resistance in trunks. The results suggest that, in 'Tempranillo' variety, branches with a lower effective section are more prone to breakage when affected by X. arvicola larvae, whereas trunks, with a greater effective section, maintain better stability. This research should be continued with the evaluation of other vine varieties and different years of X. arvicola attacks, as the current findings are based on a single variety ('Tempranillo') over a period of ten years.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA