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Materials (Basel, Switzerland) Jun 2024The micro-sintering method was used to determine the sintering basic characteristics of iron ore with Zn contents from 0 to 4%, the influence mechanism of Zn on...
The micro-sintering method was used to determine the sintering basic characteristics of iron ore with Zn contents from 0 to 4%, the influence mechanism of Zn on sintering basic characteristics of iron ore was clarified by means of thermodynamic analysis and first-principles calculations. The results showed that (1) increasing the ZnO and ZnFeO content increased the lowest assimilation temperature (LAT) but decreased the index of liquid phase fluidity (ILF) of iron ore. The addition of ZnS had no obvious effect on LAT but increased the LIF of iron ore. (2) ZnO and ZnFeO reacted with FeO and CaO, respectively, during sintering, which inhibited the formation of silico-ferrite of calcium and aluminum (SFCA). The addition of ZnS accelerated the decomposition of FeO in the N atmosphere; however, the high decomposition temperature limited the oxidation of ZnS, so the presence of ZnS had a slight inhibitory effect on the formation of SFCA. (3) The Zn concentrated in hematite or silicate and less distributed in SFCA and magnetite in the form of solid solution; meanwhile, the microhardness of the mineral phase decreased with the increase in Zn-containing solid solution content. As the adsorption of Zn on the SFCA crystal surface was more stable, the microhardness of SFCA decreased more. The decrease in microhardness and content of the SFCA bonding phase resulted in a decrease in the compressive strength of the sinter.
PubMed: 38930288
DOI: 10.3390/ma17122919 -
Materials (Basel, Switzerland) Jun 2024In recent years, there has been a significant interest in the advancement of electrochemical sensing platforms to detect antipyretic drugs with high sensitivity and...
In recent years, there has been a significant interest in the advancement of electrochemical sensing platforms to detect antipyretic drugs with high sensitivity and selectivity. The electrochemical determination of acetaminophen (PCT) was studied with strontium molybdate with a functionalized carbon nanotube (SrMoO@f-CNF) nanocomposite. The SrMoO@f-CNF nanocomposite was produced by a facial hydrothermal followed by sonochemical treatment, resulting in a significant enhancement in the PCT determination. The sonochemical process was applied to incorporate SrMoO nanoparticles over f-CNF, enabling a network-like structure. Moreover, the produced SrMoO@f-CNF composite structural, morphological, and spectroscopic properties were confirmed with XRD, TEM, and XPS characterizations. The synergistic effect between SrMoO and f-CNF contributes to the lowering of the charge transfer resistance (Rct=85 Ω·cm2), a redox potential of Epc=0.15 V and Epa=0.30 V (vs. Ag/AgCl), and a significant limit of detection (1.2 nM) with a wide response range of 0.01-28.48 µM towards the PCT determination. The proposed SrMoO@f-CNF sensor was studied with differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques and demonstrated remarkable electrochemical properties with a good recovery range in real-sample analysis.
PubMed: 38930256
DOI: 10.3390/ma17122887 -
Materials (Basel, Switzerland) Jun 2024In the last few years, a controversy has been raised regarding the nature of the chemical bonding present in phase change materials (PCMs), many of which are minerals...
In the last few years, a controversy has been raised regarding the nature of the chemical bonding present in phase change materials (PCMs), many of which are minerals such as galena (PbS), clausthalite (PbSe), and altaite (PbTe). Two opposite bonding models have claimed to be able to explain the extraordinary properties of PCMs in the last decade: the hypervalent (electron-rich multicenter) bonding model and the metavalent (electron-deficient) bonding model. In this context, a third bonding model, the electron-deficient multicenter bonding model, has been recently added. In this work, we comment on the pros and cons of the hypervalent and metavalent bonding models and briefly review the three approaches. We suggest that both hypervalent and metavalent bonding models can be reconciled with the third way, which considers that PCMs are governed by electron-deficient multicenter bonds. To help supporters of the metavalent and hypervalent bonding model to change their minds, we have commented on the chemical bonding in GeSe and SnSe under pressure and in several polyiodides with different sizes and geometries.
PubMed: 38930210
DOI: 10.3390/ma17122840 -
Materials (Basel, Switzerland) Jun 2024Three-dimensional printing (3DP) has emerged as a promising method for creating intricate scaffold designs. This study assessed three 3DP scaffold designs fabricated...
Three-dimensional printing (3DP) has emerged as a promising method for creating intricate scaffold designs. This study assessed three 3DP scaffold designs fabricated using biodegradable poly(lactic) acid (PLA) through fused deposition modelling (FDM): mesh, two channels (2C), and four channels (4C). To address the limitations of PLA, such as hydrophobic properties and poor cell attachment, a post-fabrication modification technique employing Polyelectrolyte Multilayers (PEMs) coating was implemented. The scaffolds underwent aminolysis followed by coating with SiCHA nanopowders dispersed in hyaluronic acid and collagen type I, and finally crosslinked the outermost coated layers with EDC/NHS solution to complete the hybrid scaffold production. The study employed rotating wall vessels (RWVs) to investigate how simulating microgravity affects cell proliferation and differentiation. Human mesenchymal stem cells (hMSCs) cultured on these scaffolds using proliferation medium (PM) and osteogenic media (OM), subjected to static (TCP) and dynamic (RWVs) conditions for 21 days, revealed superior performance of 4C hybrid scaffolds, particularly in OM. Compared to commercial hydroxyapatite scaffolds, these hybrid scaffolds demonstrated enhanced cell activity and survival. The pre-vascularisation concept on 4C hybrid scaffolds showed the proliferation of both HUVECs and hMSCs throughout the scaffolds, with a positive expression of osteogenic and angiogenic markers at the early stages.
PubMed: 38930181
DOI: 10.3390/ma17122811 -
Journal of Clinical Medicine Jun 2024Osteogenesis Imperfecta (OI) is a genetic disorder caused by mutations in genes responsible for collagen synthesis or polypeptides involved in the formation of collagen... (Review)
Review
Osteogenesis Imperfecta (OI) is a genetic disorder caused by mutations in genes responsible for collagen synthesis or polypeptides involved in the formation of collagen fibers. Its predominant skeletal complication is scoliosis, impacting 25 to 80% of OI patients. Vertebral deformities of the scoliotic curves in OI include a variety of malformations such as codfish, wedged-shaped vertebrae or platyspondyly, craniocervical junction abnormalities, and lumbosacral spondylolysis and spondylolisthesis. Although the precise pathophysiology of these spinal deformities remains unclear, anomalies in bone metabolism have been implicated in the progression of scoliotic curves. Bone Mineral Density (BMD) measurements have demonstrated a significant reduction in the Z-score, indicating osteoporosis and a correlation with the advancement of scoliosis. Factors such as increased mechanical strains, joint hypermobility, lower leg length discrepancy, pelvic obliquity, spinal ligament hypermobility, or vertebrae microfractures may also contribute to the severity of scoliosis. Histological vertebral analysis has confirmed that changes in trabecular microarchitecture, associated with inadequate bone turnover, indicate generalized bone metabolic defects in OI. At the molecular level, the upregulation of Transforming Growth factor-β (TGFβ) signaling in OI can lead to disturbed bone turnover and changes in muscle mass and strength. Understanding the relationship between spinal clinical features and molecular pathways could unveil TGFβ -related molecular targets, paving the way for novel therapeutic approaches in OI.
PubMed: 38930011
DOI: 10.3390/jcm13123484 -
Medicina (Kaunas, Lithuania) Jun 2024: Unhealthy nutrition can contribute to the development or progression of various alimentary-dependent diseases, including obesity, type 2 diabetes mellitus, metabolic...
: Unhealthy nutrition can contribute to the development or progression of various alimentary-dependent diseases, including obesity, type 2 diabetes mellitus, metabolic syndrome, anaemia, and arterial hypertension. Young-old and old-old individuals often have diets deficient in essential vitamins, minerals, and macronutrients, characterized by high consumption of carbohydrate-rich foods and insufficient intake of plant-based products like vegetables and fruits. This study aims to identify key parameters of nutritional status among the young-old (aged 60-74 years) and old-old (aged 75-90 years) populations in central Kazakhstan, particularly in relation to specific alimentary-dependent diseases. : The study involved 300 participants aged 60-90 years. The study incorporated a dietary questionnaire, food consumption records (such as 24 h recalls), and measurements of anthropometric indicators including weight and skinfold measurements. : Residents in the surveyed regions typically consumed food 3-4 times daily, with breakfast, lunch, and dinner being eaten at consistent times. A significant proportion of individuals, especially older adults, followed this meal schedule. About one-third ate before bedtime, and more than half believed they adhere to a specific diet. The mean BMI for men aged 60-74 years was 28.3 (95% CI: 20.1-43.2) and, for those aged 75-90 years, it was 29.0 (95% CI: 22.1-40.8). Caloric intake among individuals aged 60-74 was higher compared to those aged 75-90, with males consuming an average of 2372.7 kcal and females consuming 2236.78 kcal versus 2101.5 kcal for males and 2099.9 kcal for females in the older age group. : The dietary patterns observed among old-old individuals were marked by excessive calorie intakes and imbalances in macronutrient composition, with a predominant emphasis on high-carbohydrate foods at the expense of essential nutrients like proteins, fats, and key vitamins (such as C, E, B vitamins) and minerals (such as potassium, calcium, and iron).
Topics: Humans; Male; Female; Aged; Nutritional Status; Middle Aged; Aged, 80 and over; Kazakhstan; Surveys and Questionnaires; Diet; Body Mass Index; Energy Intake
PubMed: 38929540
DOI: 10.3390/medicina60060923 -
Medicina (Kaunas, Lithuania) May 2024In teeth with open apices, performing single session apexification is a challenging treatment due to the difficulty in handling mineral trioxide aggregate (MTA)....
In teeth with open apices, performing single session apexification is a challenging treatment due to the difficulty in handling mineral trioxide aggregate (MTA). Minimally invasive approaches in dentistry have also influenced the cavity designs in endodontics. Until now, different techniques have not been investigated in addition to manual condensation during the process of placing MTA in traditional (TradACs) or conservative (ConsACs) endodontic access cavities. The aim of this in vitro study was to compare and evaluate the obturation quality of MTA apical plugs placed with different techniques in TradACs or ConsACs. : Sixty upper central teeth were divided into two main groups based on cavity design, and then each main group was further divided into three subgroups according to MTA placement techniques ( = 10): TradAC-manual, TradAC-manual + indirect ultrasonic activation, TradAC-manual + XP-endo Shaper (XPS), ConsAC-manual, ConsAC-manual + indirect ultrasonic activation, and ConsAC-manual + XPS. Subsequently, the porosity percentages in the MTA apical plug were analyzed using micro-computed tomography. The statistical analysis was performed using the Kruskal-Wallis H test and Mann-Whitney test. Statistical significance was set at < 0.05. There were differences in volume of porosity percentages (%) according to cavity designs and MTA application techniques ( < 0.05). Except for the XPS group, more porosity was observed in ConsACs compared to TradACs. In TradACs, the significantly lowest open and total porosity was observed in the manual, ultrasonic, and XPS techniques, respectively. In ConsACs, the significantly lowest porosity was observed in the manual, XPS, and ultrasonic techniques, respectively ( 0.05). In MTA obturation, cavity designs and application techniques had an impact on the MTA porosity. Creating an apical plug in ConsACs may result in more porosity compared to TradACs, especially when manual or indirect ultrasonic activation is preferred. Opting for the manual technique alone may be considered sufficient for controlling porosity for both TradACs and ConsACs.
Topics: Calcium Compounds; Aluminum Compounds; Drug Combinations; Silicates; Humans; Oxides; X-Ray Microtomography; Root Canal Obturation; Root Canal Filling Materials; In Vitro Techniques
PubMed: 38929495
DOI: 10.3390/medicina60060878 -
Animals : An Open Access Journal From... Jun 2024To allow the original publication to be better understood [...].
To allow the original publication to be better understood [...].
PubMed: 38929456
DOI: 10.3390/ani14121829 -
Antioxidants (Basel, Switzerland) Jun 2024The importance of gamma-aminobutyric acid (GABA) in plants has been highlighted due to its critical role in mitigating metal toxicity, specifically countering the...
The importance of gamma-aminobutyric acid (GABA) in plants has been highlighted due to its critical role in mitigating metal toxicity, specifically countering the inhibitory effects of copper stress on rice plants. This study involved pre-treating rice plants with 1 mM GABA for one week, followed by exposure to varying concentrations of copper at 50 μM, 100 μM, and 200 μM. Under copper stress, particularly at 100 μM and 200 μM, plant height, biomass, chlorophyll content, relative water content, mineral content, and antioxidant activity decreased significantly compared to control conditions. However, GABA treatment significantly alleviated the adverse effects of copper stress. It increased plant height by 13%, 18%, and 32%; plant biomass by 28%, 52%, and 60%; chlorophyll content by 12%, 30%, and 24%; and relative water content by 10%, 24%, and 26% in comparison to the C50, C100, and C200 treatments. Furthermore, GABA treatment effectively reduced electrolyte leakage by 11%, 34%, and 39%, and the concentration of reactive oxygen species, such as malondialdehyde (MDA), by 9%, 22%, and 27%, hydrogen peroxide (HO) by 12%, 38%, and 30%, and superoxide anion content by 8%, 33, and 39% in comparison to C50, C100, and C200 treatments. Additionally, GABA supplementation led to elevated levels of glutathione by 69% and 80%, superoxide dismutase by 22% and 125%, ascorbate peroxidase by 12% and 125%, and catalase by 75% and 100% in the C100+G and C200+G groups as compared to the C100 and C200 treatments. Similarly, GABA application upregulated the expression of GABA shunt pathway-related genes, including gamma-aminobutyric transaminase () by 38% and 80% and succinic semialdehyde dehydrogenase () by 60% and 94% in the C100+G and C200+G groups, respectively, as compared to the C100 and C200 treatments. Conversely, the expression of gamma-aminobutyric acid dehydrogenase () was downregulated. GABA application reduced the absorption of Cu by 54% and 47% in C100+G and C200+G groups as compared to C100, and C200 treatments. Moreover, GABA treatment enhanced the uptake of Ca by 26% and 82%, Mg by 12% and 67%, and K by 28% and 128% in the C100+G and C200+G groups as compared to C100, and C200 treatments. These findings underscore the pivotal role of GABA-induced enhancements in various physiological and molecular processes, such as plant growth, chlorophyll content, water content, antioxidant capacity, gene regulation, mineral uptake, and copper sequestration, in enhancing plant tolerance to copper stress. Such mechanistic insights offer promising implications for the advancement of safe and sustainable food production practices.
PubMed: 38929139
DOI: 10.3390/antiox13060700 -
Antioxidants (Basel, Switzerland) May 2024Horticultural crops play a vital role in global food production, nutrition, and the economy. Horticultural crops are highly vulnerable to abiotic stresses. These abiotic... (Review)
Review
Horticultural crops play a vital role in global food production, nutrition, and the economy. Horticultural crops are highly vulnerable to abiotic stresses. These abiotic stresses hinder plant growth and development by affecting seed germination, impairing photosynthetic activity, and damaging root development, thus leading to a decrease in fruit yield, quality, and productivity. Scientists have conducted extensive research to investigate the mechanisms of resilience and the ability to cope with environmental stresses. In contrast, the use of phytohormones to alleviate the detrimental impacts of abiotic stresses on horticulture plants has been generally recognized as an effective method. Among phytohormones, melatonin (MT) is a novel plant hormone that regulates various plants' physiological functions such as seedling development, root system architecture, photosynthetic efficiency, balanced redox homeostasis, secondary metabolites production, accumulation of mineral nutrient uptake, and activated antioxidant defense system. Importantly, MT application significantly restricted heavy metals (HMs) uptake and increased mineral nutrient accumulation by modifying the root architecture system. In addition, MT is a naturally occurring, multifunctional, nontoxic biomolecule having antioxidant properties. Furthermore, this review described the hormonal interaction between MT and other signaling molecules in order to enhance abiotic stress tolerance in horticulture crops. This review focuses on current research advancements and prospective approaches for enhancing crop tolerance to abiotic stress.
PubMed: 38929102
DOI: 10.3390/antiox13060663