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1.
AAPS PharmSciTech ; 25(4): 79, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589718

RESUMEN

The development of suitable dosage forms is essential for an effective pharmacological treatment in children. Orally disintegrating tablets (ODTs) are attractive dosage forms that avoid swallowing problems, ensure dosage accuracy and are easy to administer as they disintegrate in the oral cavity. This study aimed to develop ODTs containing losartan potassium (LP) for the treatment of arterial hypertension in children. The ODTs, produced by the cost-effective manufacturing process of direct compression, consisted of a mixture of diluent, superdisintegrant, glidant and lubricant. Five superdisintegrants (croscarmellose sodium, two grades of crospovidone, sodium starch glycolate and pregelatinized starch) were tested (at two concentrations), and combined with three diluents (mannitol, lactose and sorbitol). Thus, thirty formulations were evaluated based on disintegration time, hardness and friability. Two formulations, exhibiting the best results concerning disintegration time (< 30 s), hardness and friability (≤ 1.0%), were selected as the most promising ones for further evaluation. These ODTs presented favourable drug-excipient compatibility, tabletability and flow properties. The in vitro dissolution studies demonstrated 'very rapid' drug release. Preliminary stability studies highlighted the requirement of a protective packaging. All quality properties retained appropriate results after 12 months of storage in airtight containers. In conclusion, the ODTs were successfully developed and characterised, suggesting a potential means to accomplish a final prototype that enables an improvement in childhood arterial hypertension treatment.


Asunto(s)
Hipertensión , Losartán , Humanos , Niño , Análisis Costo-Beneficio , Solubilidad , Administración Oral , Composición de Medicamentos/métodos , Excipientes , Hipertensión/tratamiento farmacológico , Comprimidos , Dureza
2.
PLoS One ; 19(4): e0301560, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38635736

RESUMEN

The new material introduced by the ITTF in 2014 for table tennis balls has attracted significant attention from players and coaches. Changes in both material selection and production procedures are likely to have affected the static performance of the ball. However, the raw data regarding the elasticity and hardness of these new material balls, encompassing various brands and structures, often lacks practical information crucial for players' rapid adaptation and daily training. The static properties tested in this study were provided by the ITTF, covering both hardness and elasticity. Based on computed variables, this study revealed that the hardness of seam balls at the equator was not consistently higher than that at the pole. Additionally, the study confirmed that the hardness and bounce height of new material balls exceeded those of celluloid. Furthermore, correlation analysis was conducted to examine the relationship between these two properties, revealing a significant correlation between the hardness of seamless balls and their elasticity. This study provides an analysis of the static performance of various types of new material balls, aiding players and coaches in better understanding official event balls and offering a theoretical foundation for the formulation of diverse training and game strategies.


Asunto(s)
Tenis , Dureza , Elasticidad
3.
Urolithiasis ; 52(1): 58, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38565776

RESUMEN

To evaluate the performance of a mathematical model to drive preoperative planning between RIRS and MiniPerc (MP) for the treatment of renal stones between 10 and 20 mm. Patients with a renal stone between 10 and 20 mm were enrolled. A mathematical model named Stone Management According to Size-Hardness (SMASH) score was calculated: hounsfield units (HU) χ stone maximum size (cm)/100. Patients were divided into 4 groups: RIRS with score < 15 (Group A), RIRS with score ≥ 15 (Group B), MP with score < 15 (Group C), MP with score ≥ 15 (Group D). Cyber Ho device was always used. Stone free rate (SFR) was assessed after 3 months. Complication rate and need for auxiliary procedures were evaluated. Between January 2019 and December 2021, 350 patients were enrolled (87, 88, 82 and 93 in Groups A, B, C and D). Mean stone size was 13.1 vs 13.3 mm in Group A vs B (p = 0.18) and 16.2 vs 18.1 mm in Group C vs D (p = 0.12). SFR was 82%, 61%, 75% and 85% for Groups A, B, C and D. SFR was comparable between Groups C and D (p = 0.32) and Groups A and C (p = 0.22). SFR was significantly higher in Group A over B (p = 0.03) and in Group D over B (p = 0.02). Complication rate was 2.2%, 3.4%, 12.1%, 12.9% for Groups A, B, C, D. RIRS and MP are both safe and effective. The mathematical model with the proposed cut-off allowed a proper allocation of patients between endoscopic and percutaneous approaches.Registration number of the study ISRCTN55546280.


Asunto(s)
Cálculos Renales , Láseres de Estado Sólido , Nefrostomía Percutánea , Humanos , Holmio , Láseres de Estado Sólido/efectos adversos , Dureza , Nefrostomía Percutánea/métodos , Cálculos Renales/cirugía , Resultado del Tratamiento
4.
Urolithiasis ; 52(1): 57, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563829

RESUMEN

Calcium oxalate kidney stones, the most prevalent type of kidney stones, undergo a multi-step process of crystal nucleation, growth, aggregation, and secondary transition. The secondary transition has been rather overlooked, and thus, the effects on the disease and the underlying mechanism remain unclear. Here, we show, by periodic micro-CT images of human kidney stones in an ex vivo incubation experiment, that the growth of porous aggregates of calcium oxalate dihydrate (COD) crystals triggers the hardening of the kidney stones that causes difficulty in lithotripsy of kidney stone disease in the secondary transition. This hardening was caused by the internal nucleation and growth of precise calcium oxalate monohydrate (COM) crystals from isolated urine in which the calcium oxalate concentrations decreased by the growth of COD in closed grain boundaries of COD aggregate kidney stones. Reducing the calcium oxalate concentrations in urine is regarded as a typical approach for avoiding the recurrence. However, our results revealed that the decrease of the concentrations in closed microenvironments conversely promotes the transition of the COD aggregates into hard COM aggregates. We anticipate that the suppression of the secondary transition has the potential to manage the deterioration of kidney stone disease.


Asunto(s)
Líquidos Corporales , Cálculos Renales , Litotricia , Humanos , Oxalato de Calcio , Dureza
5.
BMC Oral Health ; 24(1): 487, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658909

RESUMEN

BACKGROUND: Zinc-oxide eugenol (ZOE) cements are among the most used temporary materials in dentistry. Although ZOE has advantages over other temporary fillers, its mechanical strength is weaker, so researchers are working to improve it. E-glass fibers have emerged as promising reinforcing fibers in recent years due to their strong mechanical behavior, adequate bonding, and acceptable aesthetics. OBJECTIVES: To evaluate and compare the compressive strength, surface microhardness, and solubility of the ZOE and those reinforced with 10 wt.% E-glass fibers. METHODS: A total of 60 ZEO specimens were prepared; 30 specimens were reinforced with 10 wt.% E-glass fibers, considered modified ZOE. The characterization of the E-glass fibers was performed by XRF, SEM, and PSD. The compressive strength, surface microhardness, and solubility were evaluated. Independent sample t-tests were used to statistically assess the data and compare mean values (P ≤ 0.05). RESULTS: The results revealed that the modified ZOE showed a significantly higher mean value of compressive strength and surface microhardness while having a significantly lower mean value of solubility compared to unmodified ZOE (P ≤ 0.05). CONCLUSION: The modified ZOE with 10 wt.% E-glass fibers had the opportunity to be used as permanent filling materials.


Asunto(s)
Fuerza Compresiva , Vidrio , Dureza , Ensayo de Materiales , Solubilidad , Cemento de Óxido de Zinc-Eugenol , Cemento de Óxido de Zinc-Eugenol/química , Vidrio/química , Propiedades de Superficie , Microscopía Electrónica de Rastreo
6.
PLoS One ; 19(4): e0298404, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38598496

RESUMEN

AIM: Dental erosion is a chemical-mechanical process that leads to the loss of dental hard tissues. This study aimed to investigate the effect of pomegranate juice on the enamel. METHODS: Enamel blocks were randomly divided into three groups: deionized water, cola, and pomegranate juice. The blocks were immersed in the solutions four times a day for 14 days, and stored in artificial saliva for the remaining period. The surface hardness was measured on days 7 and 14. The surface structures of the demineralized blocks were observed via scanning electron microscopy (SEM), and the depth of demineralization was observed via confocal laser scanning microscopy (CLSM). The pH, calcium, and phosphorus levels of the three solutions were analyzed. RESULTS: The microhardness values of the blocks in the pomegranate juice and cola groups decreased with the increase in the demineralization time. The blocks in the pomegranate juice group exhibited large fractures in the enamel column, whereas those in the cola group had pitted enamels with destruction of the interstitial enamel column. Compared with cola group, fluorescent penetration increased in pomegranate juice (P < 0.01). The pH of cola (2.32 ± 0.09) was lower than that of pomegranate juice (3.16 ± 0.16). Furthermore, the calcium content in pomegranate juice was significantly higher than that in cola (P < 0.01). Alternatively, the concentration of phosphorous in cola was significantly higher than that in pomegranate juice (P < 0.01). CONCLUSION: These findings indicate that pomegranate juice can cause enamel demineralization with an erosive potential comparable to that of cola.


Asunto(s)
Granada (Fruta) , Erosión de los Dientes , Humanos , Calcio , Concentración de Iones de Hidrógeno , Erosión de los Dientes/inducido químicamente , Dureza , Cola , Esmalte Dental
7.
Braz Oral Res ; 38: e030, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38597548

RESUMEN

This study aimed to evaluate volumetric polymerization shrinkage, degree of conversion and Vickers hardness of four bulk-fill resin composites light-activated with their dedicated light curing units (LCUs). Four groups were evaluated, according to the type of composite and curing mode: Tetric EvoCeram Bulk-fill (TEBO) and Tetric EvoFlow Bulk-fill (TEBF) were light-activated with Bluephase Style 20i (20s, in high-mode), while Tetric Powerfill (TEPO) and Tetric Powerflow (TEPF) were light-activated with Bluephase PowerCure (3s). Volumetric polymerization shrinkage test (n = 6) was performed in standardized box-shaped class-I cavities of extracted third molars (4 x 4 x 4 mm). Teeth were scanned before and after resin composite application by micro-computed tomography, and acquired data were evaluated with Amira software. Degree of conversion (n = 5) was evaluated at the top and bottom surfaces of composite cylindric samples (4 mm diameter, 4 mm thickness) using an FT-IR spectrometer (spectra between 1,500 and 1,800 cm-1, 40 scans at a resolution of 4 cm-1). Three Vickers indentations (50 g / 15 s), spaced 500 µm apart, were performed on the top and bottom composite surfaces and averaged. One-way ANOVA was used for data evaluation. TEPF showed the lowest volumetric polymerization shrinkage (p < 0.05), while the other composites were not significantly different within each other (p > 0.05). All materials presented a significant decrease in degree of conversion and Vickers hardness when compared top to bottom surfaces (p < 0.05). Bottom to top surface ratios for degree of conversion ranged from 0.8 (TEBO and TEPO) to 0.9 (TEBF and TEPF), and from 0.4 (TEPO) to 0.7 (TEBF and TEPF) for hardness. In conclusion, resinous materials present a decrease in hardness and degree of conversion from top to bottom even when a higher power is used, while the flowable material TEPF showed the lowest volumetric shrinkage values compared to the other materials.


Asunto(s)
Resinas Compuestas , Caries Dental , Humanos , Dureza , Microtomografía por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Ensayo de Materiales , Polimerizacion , Propiedades de Superficie , Materiales Dentales
8.
Sci Rep ; 14(1): 9387, 2024 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-38653765

RESUMEN

The study aimed to compare various toothpastes and mouthwashes on permanent tooth dentin after erosive and abrasive challenges. 130 sound premolars dentin were randomly submitted to an initial erosive challenge and a cycle of erosive and abrasive challenges for five days. The five experimental groups (n = 26) were: (1) Control group (artificial saliva), (2) Elmex erosion protection toothpaste and mouthwash, (3) Vitis anticaries biorepair toothpaste and mouthwash, (4) Oral B Pro-expert toothpaste and Oral B Fluorinse mouthwash, and (5) MI Paste ONE toothpaste and Caphosol mouthwash. Microhardness, surface roughness values, and the topographical characteristics of the dentin surface were assessed. The highest percentage of recovered dentin microhardness (%RDMH) value was observed in groups 2 and 4, followed by groups 5 and 3, respectively. The %RDMH values in groups 2 and 4 did not demonstrate a significant difference (p = 0.855). The highest percentage of improvement in surface roughness was recorded in groups 2 and 4, with no significant differences (p = 0.989). The atomic force microscopy (AFM) findings were consistent with the surface roughness data. The best recovery of dentin microhardness and roughness were measured with the Elmex and Oral B toothpaste and mouthwash, followed by MI Paste ONE toothpaste and Caphosol mouthwash and Vitis anticaries biorepair toothpaste and mouthwash.


Asunto(s)
Dentina , Antisépticos Bucales , Erosión de los Dientes , Pastas de Dientes , Pastas de Dientes/farmacología , Antisépticos Bucales/farmacología , Humanos , Dentina/efectos de los fármacos , Erosión de los Dientes/prevención & control , Propiedades de Superficie , Dureza , Técnicas In Vitro
9.
J Dent Res ; 103(5): 536-545, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38549255

RESUMEN

Dimethacrylate-based chemistries feature extensively as resin monomers in dental resin-based materials due to their distinguished overall performance. However, challenges endure, encompassing inadequate mechanical attributes, volumetric shrinkage, and estrogenicity. Herein, we first synthesized a novel resin monomer, 9-armed starburst polyurethane acrylate (NPUA), via the grafting-onto approach. Compared to the primary commercial dental monomer 2,2-bis [p-(2'-hydroxy-3'-methacryloxypropoxy) phenyl] propane (Bis-GMA) (with a viscosity of 1,174 ± 3 Pa·s and volumetric shrinkage of 4.7% ± 0.1%), the NPUA monomer achieves the lower viscosity (158 ± 1 Pa·s), volumetric shrinkage (2.5% ± 0.1%), and cytotoxicity (P < 0.05). The NPUA-based resins exhibit the higher flexural strength, flexural modulus, hardness, and hydrophobicity and lower volumetric shrinkage, water absorption, and solubility compared to the Bis-GMA (70 wt%)/TEGDMA (30 wt%) resins. The NPUA-based composites exhibit significantly higher flexural strength, flexural modulus, and hardness and lower volumetric shrinkage (171.4 ± 3.0 MPa, 12.6 ± 0.5 GPa, 2.0 ± 0.2 GPa, and 3.4% ± 0.2%, respectively) compared to the Bis-GMA group (120.3 ± 4.7 MPa, 9.4 ± 0.7 GPa, 1.5 ± 0.1 GPa, and 4.7% ± 0.2%, respectively; P < 0.05). This work presents a viable avenue for augmenting the physicochemical attributes of dental resins.


Asunto(s)
Resinas Acrílicas , Ensayo de Materiales , Metacrilatos , Poliuretanos , Poliuretanos/química , Viscosidad , Metacrilatos/química , Resinas Compuestas/química , Resistencia Flexional , Materiales Dentales/química , Bisfenol A Glicidil Metacrilato/química , Polimerizacion , Ácidos Polimetacrílicos/química , Dureza , Propiedades de Superficie
10.
Environ Sci Pollut Res Int ; 31(17): 25991-26005, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492138

RESUMEN

The use of geopolymers (GP) in cementitious composites provides a solution to reduce the significant carbon emissions associated with conventional cement production, thereby advancing environmentally friendly concrete construction practices. The promise of hybrid fiber-reinforced fly ash (FA)-based GP (HFGP) composites that combine microfibers and nanoparticles has not yet been fully comprehended. This research aims to enhance the mechanical and microstructural properties of HFGP blends by varying the proportion of nano calcium carbonate ( n - C a C O 3 ). The production of HFGP involved the use of two types of fibers: 1% carbon fibers and 0.5% basalt fibers. To achieve HFGP blends with a consistent fiber ratio, we incorporated four different levels of n - C a C O 3 , comprising 1%, 2%, 3%, and 4% of the mixture. The analysis of fractured samples encompassed microstructural and mineralogical characterization, which was conducted using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) analysis. The results unveiled that the HFGP blend containing 3% n - C a C O 3 exhibited the highest levels of hardness, compressive strength, toughness modulus, and flexural strength while the use of 2% n - C a C O 3 produced the highest results for fracture toughness and impact strength. SEM analysis illustrated that n - C a C O 3 had a significant positive impact on the microstructure of GP. A considerable rise in hump intensity between 20 and 40 °C ( 2 θ ) was also seen in the XRD examination, indicating that calcium silicate hydrate (CSH) had formed after the primary binder, such as sodium aluminosilicate hydrate (NASH), had been present. The stretching of O-H bonds in water molecules was also seen in the HFGP spectra at 3399, 3436, 3436, and 3438 cm-1. Due to the higher water content in the HFGP network, which may influence the material's strength, these bands were more apparent and larger in specimens with additions of nanoparticles and hybrid fibers.


Asunto(s)
Nanocompuestos , Ensayo de Materiales , Dureza , Fuerza Compresiva , Nanocompuestos/química , Agua
11.
J Mech Behav Biomed Mater ; 154: 106501, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38531182

RESUMEN

OBJECTIVE: The influence of various aging protocols, representing and accelerating influences present in the dental context, on possible changes in the microstructure and mechanical properties of thermoplastics was investigated. In order to minimize the complexity of the systems, first pure polymers and then later the equivalent dental polymeric materials were analyzed. MATERIALS AND METHODS: Pure polymers (Poly(methyl methacrylate) - PMMA, Polyoxymethylene homopolymer - POM-H, Polyether ether ketone - PEEK, Nylon 12 - PA12, Polypropylene - PP) were analyzed before as well as after applying different aging protocols relevant to the oral environment (ethanol, thermocycling, alkaline and acidic setting) by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The thermoanalytical parameters used were glass transition temperature (Tg), melting peak and crystallization peak temperature (Tpm, Tpc) and decomposition behavior. In a second step selected commercially available dental products (Telio CAD - PMMAD, Zirlux Acetal - POMD, Juvora Natural Dental Disc - PEEKD) aged by the protocol that previously showed strong effects were examined and additionally tested for changes in their Vickers and Martens hardness by Mann-Whitney-U test. RESULTS: The combinations of pure polymers and viable aging protocols analyzed within this study were identified via TGA or DSC as PA12 & thermocycling, POM-H & denture cleanser/lactic acid/ethanol, PP & lactic acid. The dental polymeric materials PMMAD and POMD due to aging in lactic acid showed slight but significantly (p < 0.01) reduced Vickers and partly Martens hardness. PEEK showed the greatest material resistance within this study.


Asunto(s)
Benzofenonas , Mustelidae , Polimetil Metacrilato , Animales , Polimetil Metacrilato/química , Ensayo de Materiales , Dureza , Polímeros/química , Polietilenglicoles/química , Cetonas/química , Etanol , Ácido Láctico , Materiales Dentales , Propiedades de Superficie
12.
J Mech Behav Biomed Mater ; 154: 106529, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38552335

RESUMEN

Si3N4 bioceramics were fabricated using GPS and SPS method with MgO-RE2O3 (RE = La, Nd, Gd, Ho and Lu) sintering additives. The effect of sintering methods and sintering additives on the grain growth, mechanical, antimicrobial properties and color of Si3N4 bioceramics were studied. Samples sintered with GPS are composed of ß-Si3N4 and samples sintered with SPS are composed of α-Si3N4 and ß-Si3N4. The growth of ß-Si3N4 grains in samples sintered with GPS are more adequate. Samples sintered with GPS exhibit a S. aureus inactivation rate up to 98% and a bright color appearance with a hardness of about 13 GPa and a fracture toughness up to 7.5 MPa m1/2, suitable for dental implants. And samples sintered with SPS exhibit a hardness of about 17 GPa and a fracture toughness about 6 MPa m1/2.


Asunto(s)
Antiinfecciosos , Staphylococcus aureus , Ensayo de Materiales , Cerámica , Dureza
13.
Braz Dent J ; 35: e245728, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38537023

RESUMEN

This study analyzed the physical-chemical properties of bioactive ionomer materials. Cention N bioactive materials were evaluated chemically activated (CN) and light-cured (CN-LC), Equia Forte Fill (EQUI); conventional resin composite Filtek Z350 XT (Z350); resin glass ionomer cement Riva light Cure (RIVA) and flowable resin composite Filtek Bulk Fill Flow (BULK-F) were evaluated. Sixty specimens (n=10) were prepared for sorption (SR), solubility (SL), flexural strength (FS), shrinkage stress (SS), conversion degree (CD), microhardness (MI), and surface roughness (SR) tests. Non-cured and light-cured materials were assessed on FTIR. 30 human molar teeth were used in the bond strength test (BS). Data were subjected to ANOVA and post-hoc Tukey's test (5% of significance). EQUI showed more sorption in SR and no statistical difference from RIVA and CN-LC. CN group showed more solubility and EQUI presented less (p<0.05). BULK-F showed higher FS (MPa), without differences from CN and Z350, whereas EQUI presented the lowest FS not differing from RIVA. BULK-F and CN-LC showed more shrinkage stress differing from EQUI. CN-LC and CN showed higher CD differing from the other which showed no differences (p>0.05) between them. EQUI showed the highest hardness (p<0.05) in MI. There were no differences (p>0.05) in SR (µm). Z350 and BULK-F presented higher BS, whereas CN-LC showed the lowest, although not differing from EQUI and RIVA. Equia Forte's solubility and microhardness make it a good alternative as a restorative material. Cention N degree of conversion and flexural strength making it an esthetic option to amalgam.


Asunto(s)
Resinas Compuestas , Cementos de Ionómero Vítreo , Humanos , Ensayo de Materiales , Resinas Compuestas/química , Materiales Dentales/química , Resistencia Flexional , Dureza
14.
BMC Med Inform Decis Mak ; 24(1): 88, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38539201

RESUMEN

BACKGROUND: The pharmaceutical industry is continually striving to innovate drug development and formulation processes. Orally disintegrating tablets (ODTs) have gained popularity due to their quick release and patient-friendly characteristics. The choice of excipients in tablet formulations plays a critical role in ensuring product quality, highlighting its importance in tablet creation. The traditional trial-and-error approach to this process is both expensive and time-intensive. To tackle these obstacles, we introduce a fresh approach leveraging machine learning and deep learning methods to automate and enhance pre-formulation drug design. METHODS: We collected a comprehensive dataset of 1983 formulations, including excipient names, quantities, active ingredient details, and various physicochemical attributes. Our study focused on predicting two critical control test parameters: tablet disintegration time and hardness. We compared a range of models like deep learning, artificial neural networks, support vector machines, decision trees, multiple linear regression, and random forests. RESULTS: A 12-layer deep neural network, as a form of deep learning, surpassed alternative techniques by achieving 73% accuracy for disintegration time and 99% for tablet hardness. This success underscores its efficacy in predicting complex pharmaceutical factors. Such an approach streamlines the drug formulation process, reducing iterations and material consumption. CONCLUSIONS: Our findings highlight the deep learning potential in pharmaceutical formulations, particularly for tablet hardness prediction. Future work should focus on enlarging the dataset to improve model effectiveness and extend its application in pharmaceutical product development and assessment.


Asunto(s)
Inteligencia Artificial , Excipientes , Humanos , Solubilidad , Dureza , Comprimidos
15.
Food Chem ; 446: 138829, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38442681

RESUMEN

The influence of starch granule surface proteins (SGSPs) and starch granule-associated proteins (SGAPs) on bread retrogradation was investigated in a reconstituted dough system. The removal of both SGSPs and SGAPs resulted in poor bread qualities, decreasing specific volume and crumb porosity, leading to more baking loss and compact crumb structure. Particularly, removing SGSPs was effective in promoting the bread retrogradation. After 7 days of storage, the hardness of bread without SGSPs showed an increase of 353.34 g than the bread without SGAPs. Proton population and relaxation times exhibited that the absence of SGSPs significantly decreased the content of bound water from 11.51 % to 7.03 %, indicating lower water-holding capacity due to the loosen gelling structure. Compared to the control group, bread without SGSPs accelerated the starch recrystallinity by a reduction in soluble starch content, thereby increasing the retrogradation enthalpy and relative crystallinity through promoting the molecular reassociation in starch.


Asunto(s)
Pan , Agua , Almidón/química , Termodinámica , Dureza
16.
Environ Geochem Health ; 46(4): 134, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38483664

RESUMEN

Familiarity with the chemical characteristics of regional groundwater can provide important guidance and reference for the development of regional groundwater exploitation. Jianghan Plain has been reported to have high groundwater total hardness (TH), resulting in the inability of local groundwater to be directly used as drinking water. In order to explore the causes of high TH, the paper analyzed the hydrochemical characteristics of shallow groundwater in Jianghan Plain combined with software of SPSS, JMP, and PHEEQC. The results showed that the cations in the groundwater in the area were mainly Ca2+, while the anions were mainly HCO3-. 20% of groundwater exceed the China national guideline for TH (i.e., 450 mg/L). The groundwater chemistry in the study area was controlled by three main factors of dissolution of carbonate rocks, human activities, and redox conditions, among which the interaction between water and rock had the greatest impact. The water carbonate rock interaction within Jianghan Plain was affected by various factors such as water flow and aquifers and showed a gradually weakening trend from west to east. This work not only strengthened the understanding of the causes of the high TH of groundwater in the region, but also provided reference value for regional groundwater environmental management.


Asunto(s)
Agua Potable , Agua Subterránea , Contaminantes Químicos del Agua , Humanos , Monitoreo del Ambiente/métodos , Dureza , Contaminantes Químicos del Agua/análisis , Agua Subterránea/análisis , Calidad del Agua , Agua Potable/análisis , China , Carbonatos/análisis
17.
Int J Biol Macromol ; 265(Pt 1): 130532, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38431009

RESUMEN

As a bio-based material, microcrystalline cellulose (MCC) has been applied in many fields including pharmaceuticals, foods, and cosmetics in recent years. However, traditional preparation methods of MCC are facing many challenges due to economic and eco-environmental issues. In this study, softwood dissolved pulp was sieved to long fiber (LF) and short fiber (SF), and subsequently to prepare LF-MCC and SF-MCC by hydrochloric acid hydrolysis at different acid dosages (3-7 wt%), reaction times (30-90 min), and temperatures (75-95 °C). The as-obtained MCC products were compared in terms of morphology, size, crystallinity, and chemical structure. The results indicated that the crystallinity and yield of LF-MCC were high, with maximum values of 78.41 % and 98.68 %, respectively. The particle size distribution of SF-MCC was more uniform in the range of 20-80 µm, with a maximum of 59.44 % at 20-80 µm occupancy proportion. Moreover, SF-MCC had a typical rod-like shape and larger surface area as well as better thermal behavior than LF-MCC. When LF-MCC and SF-MCC were used as fillers in the production of ibuprofen tablets, the tablets added with LF-MCC exhibited higher hardness, friability, dissolution rate, and shorter disintegration time. Therefore, this work is very beneficial for the preparation and application of MCC.


Asunto(s)
Celulosa , Ibuprofeno , Celulosa/química , Dureza , Comprimidos
18.
Sci Rep ; 14(1): 7087, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38528204

RESUMEN

To evaluate the efficiency and effectiveness of three minimally invasive (MI) techniques in removing deep dentin carious lesions. Forty extracted carious molars were treated by conventional rotary excavation (control), chemomechanical caries removal agent (Brix 3000), ultrasonic abrasion (WOODPECKER, GUILIN, China); and Er, Cr: YSGG laser ablation (BIOLASE San Clemente, CA, USA). The assessments include; the excavation time, DIAGNOdent pen, Raman spectroscopy, Vickers microhardness, and scanning electron microscope combined with energy dispersive X-ray spectroscopy (SEM-EDX). The rotary method recorded the shortest excavation time (p < 0.001), Brix 3000 gel was the slowest. DIAGNOdent pen values ranged between 14 and 18 in the remaining dentin and laser-ablated surfaces recorded the lowest reading (p < 0.001). The Ca:P ratios of the remaining dentin were close to sound dentin after all excavation methods; however, it was higher in the ultrasonic technique (p < 0.05). The bur-excavated dentin showed higher phosphate and lower matrix contents with higher tissue hardness that was comparable to sound dentin indicating the non-selectiveness of this technique in removing the potentially repairable dentin tissue. In contrast, the MI techniques exhibited lower phosphate and higher organic contents associated with lower microhardness in the deeper dentin layers. This was associated with smooth residual dentin without smearing and patent dentinal tubules. This study supports the efficiency of using MI methods in caries removal as conservative alternatives to rotary excavation, providing a promising strategy for the clinical dental practice.


Asunto(s)
Caries Dental , Láseres de Estado Sólido , Humanos , Dentina/química , Susceptibilidad a Caries Dentarias , Dureza , Fosfatos/análisis , Caries Dental/cirugía , Caries Dental/patología
19.
J Biomech ; 165: 111996, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38377740

RESUMEN

High loading impact associated with heel strikes causes running injuries. This study aimed to investigate how loading impact is affected by midsole hardness and running surface type. Twelve young rear-foot runners ran at a fixed speed along an 18 m runway wearing shoes with different midsole hardness (Asker C-45, C-50, C-55, C-60, from soft to hard) and on two different surfaces (rubber and concrete). We quantified vertical average loading rate (VALR) and vertical impact peak force (VIPF). We conducted midsole × surface repeated-measures ANOVA on loading impact measures, and one-sample t-tests to compare VALR with a threshold value (80 BW·s-1). Midsole hardness and surface type mainly affected VALR. Although no significant effect of these variables was observed for VIPF magnitude, there were effects on time to VIPF and steps with VIPF. Several combinations of midsole and surface hardness reduced VALR below 80 BW·s-1: Asker C-45 with both surfaces, and Asker C-50 with a rubber surface. The combination of softer midsole and surface effectively reduced loading rates as shown by increased time to VIPF and reduced VALR. Combining softer midsole and surface results in the greatest cushioning, which demonstrates the benefit of considering both factors in reducing running injuries.


Asunto(s)
Pie , Goma , Dureza , Fenómenos Biomecánicos , Zapatos
20.
J Microbiol Biotechnol ; 34(4): 846-853, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38379340

RESUMEN

Adzuki bean (Vigna angularis), which provides plant-based proteins and functional substances, requires a long soaking time during processing, which limits its usefulness to industries and consumers. To improve this, ultrasonic treatment using high pressure and shear force was judged to be an appropriate pretreatment method. This study aimed to determine the optimal conditions of ultrasound treatment for the improved hydration of adzuki beans using the response surface methodology (RSM). Independent variables chosen to regulate the hydration process of the adzuki beans were the soaking time (2-14 h, X1), treatment intensity (150-750 W, X2), and treatment time (1-10 min, X3). Dependent variables chosen to assess the differences in the beans post-immersion were moisture content, water activity, and hardness. The optimal conditions for treatment deduced through RSM were a soaking time of 12.9 h, treatment intensity of 600 W, and treatment time of 8.65 min. In this optimal condition, the values predicted for the dependent variables were a moisture content of 58.32%, water activity of 0.9979 aw, and hardness of 14.63 N. Upon experimentation, the results obtained were a moisture content of 58.28 ± 0.56%, water activity of 0.9885 ± 0.0040 aw, and hardness of 13.01 ± 2.82 g, confirming results similar to the predicted values. Proper ultrasound treatment caused cracks in the hilum, which greatly affects the water absorption of adzuki beans, accelerating the rate of hydration. These results are expected to help determine economically efficient processing conditions for specific purposes, in addition to solving industrial problems associated with the low hydration rate of adzuki beans.


Asunto(s)
Manipulación de Alimentos , Vigna , Agua , Vigna/química , Agua/química , Manipulación de Alimentos/métodos , Ultrasonido , Dureza , Factores de Tiempo , Ondas Ultrasónicas , Semillas/química , Fabaceae/química
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