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1.
Nutrition ; 123: 112414, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38564838

RESUMO

OBJECTIVE: Cross-sectional evidence has demonstrated that parallel reactance obtained by bioelectrical impedance analysis (BIA) may be an alternative to the regularly used series of measurements to predict intracellular water (ICW) in athletes. However, we are not aware of any studies that have determined the predictive role or compared the effectiveness of both series and parallel reactance for tracking ICW changes during an athletic season. The main aim of this study was to determine the predictive role and compare both series and parallel reactance (Xc) in tracking ICW during an athletic season. RESEARCH METHODS AND PROCEDURES: This longitudinal study analyzed 108 athletes in the preparatory and competitive periods. Using dilution techniques, total body water (TBW) and extracellular water (ECW) were determined and ICW was calculated. Resistance (R), Xc, and impedance (Z) standardized for height were obtained through BIA spectroscopy using a frequency of 50kHz in a series array and then mathematically transformed in a parallel array. RESULTS: Multiple regression analyses showed that only changes in parallel Xc and capacitance (CAP) (P < 0.05) were predictors of delta ICW during the sports season. In contracts, this was not the case for Xcs. Both changes in R and Z, series and parallel, predicted similarly the changes in ECW and TBW (P < 0.05) in athletes. CONCLUSION: Our findings highlight the potential of parallel BIA values to detect changes in body water compartments over a competitive season. These data provide preliminary evidence that changes in parallel Xc/H, and ultimately CAP, represent valid markers of alterations in cell volume during a sports season.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38602190

RESUMO

Hydrophilic anti-icing coatings can be energy-effective passive solutions for combating ice accretion and reducing ice adhesion. However, their underlying mechanisms of action remain inferential and are ill-defined from a molecular perspective. Here, we systematically investigate the influence of the counterion identity on the shear ice adhesion strength to cationic polymer coatings having quaternary alkyl ammonium moieties as chargeable groups. Temperature-dependent molecular information on the hydrated polymer films is obtained using total internal reflection (TIR) Raman spectroscopy, complemented with differential scanning calorimetry (DSC) and ellipsometry. Ice adhesion measurements show a pronounced counterion-specific behavior with a sharp increase in adhesion at temperatures that depend on the anion identity, following the order Cl- < F- < SCN- < Br- < I-. Linked to the freezing of hydration water, the specific ordering results from differences in ion pairing and the amount of water present within the polymer film. Moreover, similar effects can be promoted by varying the cross-linking density in the coating while keeping the anion identity fixed. These findings shed new light on low ice adhesion mechanisms and may inspire novel approaches for improved anti-icing coatings.

3.
Materials (Basel) ; 17(3)2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38591432

RESUMO

Using limestone powder (LP), the by-product of manufactured sand, to replace part of fly ash (FA) or manufactured sand could not only turn waste into treasure and decrease the price of concrete, but could also enhance the performance of concrete and reduce environmental pollution. However, the impact of various LP incorporation methods on the performance of mass concrete was inconsistent. In this paper, the effects of LP on the workability, compressive strength, constrained expansion rate, hydration temperature and impermeability of mass concrete were studied by replacing FA or manufactured sand alone and replacing FA and manufactured sand simultaneously. The results showed that the impact of LP on the performance of mass concrete was equal when it replaced FA alone and FA and manufactured sand at the same time. When the replacement amount was 20%, the workability, expansibility and early strength of concrete were improved, but the later strength and impermeability were slightly reduced. The workability, compressive strength, expansibility and impermeability of mass concrete were improved when manufactured sand was replaced alone, and the optimal dosage was 10%. The LP, moreover, reduced the hydration temperature peak of concrete in three kinds of mixing methods, but the temperature peak appeared earlier. At lower dosages, LP optimized pore structure and promoted the early hydration of cement through filler effects and nucleation effects. When LP replaced manufactured sand, the microstructure of concrete was more dense, so the replacement of manufactured sand had a better effect on the improvement of concrete properties. A reference value for the use of LP in mass concrete is provided in this study.

4.
Materials (Basel) ; 17(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38591570

RESUMO

Hydration plays a crucial role in cement composites, but the traditional methods for measuring hydration heat face several limitations. In this study, we propose a machine learning-based approach to predict hydration heat at specific time points for three types of cement composites: ordinary Portland cement pastes, fly ash cement pastes, and fly ash-metakaolin cement composites. By adjusting the model architecture and analyzing the datasets, we demonstrate that the optimized artificial neural network model not only performs well during the learning process but also accurately predicts hydration heat for various cement composites from an extra dataset. This approach offers a more efficient way to measure hydration heat for cement composites, reducing the need for labor- and time-intensive sample preparation and testing. Furthermore, it opens up possibilities for applying similar machine learning approaches to predict other properties of cement composites, contributing to efficient cement research and production.

5.
Br J Nurs ; 33(8): S18-S25, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38639746

RESUMO

Following a serious incident and inquest after the death of a patient due to choking at Sheffield Teaching Hospitals NHS Foundation Trust, the Trust put in place an action plan and implemented strategies to reduce the risk of recurrence. Four key actions were identified as essential to try to reduce the risk of a similar event: introduction of a standard operating procedure for mealtimes that included a pre-meal safety 'pause'; use of an electronic communication icon to indicate modified diet/fluid requirements, from emergency department and onward as a patient is transferred; job-specific mealtime safety training; and use of bedside posters with specific dietary requirements (in line with the International Dysphagia Diet Standards Initiative Framework). A new role of Lead Educator for Nutrition was introduced to support the changes and provide training. Changes were also made to the incident reporting system to ensure easy identification of events relating to dysphagia, so that these could be monitored, themes identified and lessons shared. A series of audits following the changes have shown that more staff across disciplines and teams have accessed training on nutrition and hydration practices, wards have increased the use of the icon and posters, and successfully implemented pre-meal safety pauses. The Lead Educator for Nutrition has helped embed learning, and increased awareness and knowledge about nutrition and hydration.


Assuntos
Transtornos de Deglutição , Humanos , Hospitais , Dieta , Estado Nutricional , Aprendizagem
6.
Ann Dermatol ; 36(2): 99-111, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38576248

RESUMO

BACKGROUND: Skin barrier function assessment is commonly done by measuring transepidermal water loss (TEWL). An important limitation of this method is the influence of intrinsic and extrinsic factors. Electrical impedance spectroscopy (EIS) is a lesser-established method for skin barrier function assessment. Some influential factors have been described, but no guidelines exist regarding the standardization of these measurements. OBJECTIVE: To evaluate the effect size of daily routine activities on TEWL and EIS, as well as their correlation with age and anatomical differences. METHODS: Healthy participants (n=31) were stratified into three age groups (18-29, 30-49, and ≥50 years). In a climate-controlled room, EIS and TEWL measurements were performed on the left and right volar forearm and abdomen. RESULTS: Body cream application decreased TEWL and EIS values after 15 and 90 minutes. Skin washing decreased TEWL for 15 minutes and EIS values for at least 90 minutes. TEWL was increased 5 minutes after moderate to intense exercise. Coffee intake increased TEWL on the abdomen after 60 minutes. TEWL and EIS values did not correlate with participants' age and no anatomical differences were observed. No correlation was observed between TEWL and EIS. CONCLUSION: Body cream application and skin washing should be avoided at least 90 minutes prior to measurements of TEWL and EIS. Exercise and coffee intake should also be avoided prior to TEWL measurements. EIS may be a promising tool for skin barrier function assessment as it is less affected by daily routine activities than TEWL.

7.
Polymers (Basel) ; 16(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611256

RESUMO

With the development of the shipbuilding industry, it is necessary to improve tribological properties of polyether ether ketone (PEEK) as a water-lubricated bearing material. In this study, the sulfonated PEEK (SPEEK) with three distinct chemical structures was synthesized through direct sulfonated polymerization, and high fault tolerance and a controllable sulfonation degree ensured the batch stability. The tribological and mechanical properties of SPEEK with varying side groups (methyl and tert-butyl) and rigid segments (biphenyl) were compared after sintering in a vacuum furnace. Compared to the as-made PEEK, as the highly electronegative sulfonic acid group enhanced the hydration lubrication, the friction coefficient and wear rate of SPEEK were significantly reduced by 30% and 50% at least without affecting the mechanical properties. And lower steric hindrance and entanglement between molecular chains were proposed to be partially responsible for the lowest friction behavior of SPEEK with methyl side groups, making it a promising and competitive option for water-lubricated bearings.

8.
Nutrients ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38613006

RESUMO

BACKGROUND: Water intake and hydration status may potentially influence maternal and child health. However, there is little research regarding this topic. OBJECTIVES: This study aimed to investigate pregnant women's total fluid intake (TFI) levels, hydration status, and body composition and further explore their relationship with infant birth weight. METHODS: A 7-day, 24 h fluid intake recorded was applied to determine participants' TFI levels. Morning urine samples were collected and tested to evaluate their hydration status. Maternal body compositions in their third trimester and infant birth weights were measured. RESULTS: A total of 380 participants completed the study. The TFI was insufficient for pregnant women during their third trimester (median = 1574 mL), with only 12.1% of participants meeting the recommended adequate fluid intake level for pregnant women living in China (1.7 L per day). With the increasing TFI values, the urine osmolality decreased, which showed statistical significance among the four groups (χ2 = 22.637, p < 0.05). The participants displayed a poor hydration status. Meanwhile, the percentage of participants who were in dehydrated status decreased (χ2 = 67.618, p < 0.05), while body water content and basal metabolic rate increased with the increase in TFI levels (χ2 = 20.784, p < 0.05; χ2 = 14.026, p < 0.05). There were positive linear relationships between plain water intake, the basal metabolic rate of pregnant women and their infant birth weight (SE = 0.153, p < 0.05; SE = 0.076, p < 0.05). CONCLUSIONS: Water intake was insufficient, and poor hydration status was common among pregnant women in China. There may be potential relationships between plain water intake, basal metabolic rate, and infant birth weight.


Assuntos
Ingestão de Líquidos , Gestantes , Gravidez , Criança , Lactente , Humanos , Feminino , Peso ao Nascer , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Composição Corporal , China
9.
J Colloid Interface Sci ; 666: 393-402, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38603881

RESUMO

Humic acids (HA) are ubiquitous in surface waters, leading to significant fouling challenges. While zwitterion-like and zwitterionic surfaces have emerged as promising candidates for antifouling, a quantitative understanding of molecular interaction mechanism, particularly at the nanoscale, still remains elusive. In this work, the intermolecular forces between HA and charged, zwitterion-like or zwitterionic monolayers in aqueous environments were quantified using atomic force microscope. Compared to cationic MTAC ([2-(methacryloyloxy)ethyl]trimethylammonium chloride), which exhibited an adhesion energy of âˆ¼1.342 mJ/m2 with HA due to the synergistic effect of electrostatic attraction and possible cation-π interaction, anionic SPMA (3-sulfopropyl methacrylate) showed a weaker adhesion energy (∼0.258 mJ/m2) attributed to the electrostatic repulsion. Zwitterion-like MTAC/SPMA mixture, driven by electrostatic attraction between opposite charges, formed a hydration layer that prevented the interaction with HA, thereby considerably reducing adhesion energy to âˆ¼0.123 mJ/m2. In contrast, zwitterionic MPC (2-methacryloyloxyethyl phosphorylcholine) and DMAPS ([2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide) displayed ultralow adhesion energy (0.06-0.07 mJ/m2) with HA, arising from their strong dipole moments which could induce a tight hydration layer that effectively inhibited HA fouling. The pH-mediated electrostatic interaction resulted in the increased adhesion energy for MTAC but decreased adhesion energy for SPMA with elevated pH, while the adhesion energy for zwitterion-like and zwitterionic surfaces was independent of environmental pH. Density functional theory (DFT) simulation confirmed the strong binding capability of MPC and DMAPS with water molecules (∼-12 kcal mol-1). This work provides valuable insights into the molecular interaction mechanisms underlying humic-substance-fouling resistance of charged, zwitterion-like and zwitterionic materials at the nanoscale, shedding light on developing more effective strategy for HA antifouling in water treatment.

10.
Bone ; 183: 117089, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38575047

RESUMO

INTRODUCTION: Patients with chronic kidney disease (CKD) are at an alarming risk of fracture compared to age and sex-matched non-CKD individuals. Clinical and preclinical data highlight two key factors in CKD-induced skeletal fragility: cortical porosity and reduced matrix-level properties including bone hydration. Thus, strategies are needed to address these concerns to improve mechanical properties and ultimately lower fracture risk in CKD. We sought to evaluate the singular and combined effects of mechanical and pharmacological interventions on modulating porosity, bone hydration, and mechanical properties in CKD. METHODS: Sixteen-week-old male C57BL/6J mice underwent a 10-week CKD induction period via a 0.2 % adenine-laced casein-based diet (n = 48) or remained as non-CKD littermate controls (Con, n = 48). Following disease induction (26 weeks of age), n = 7 CKD and n = 7 Con were sacrificed (baseline cohort) to confirm a steady-state CKD state was achieved prior to the initiation of treatment. At 27 weeks of age, all remaining mice underwent right tibial loading to a maximum tensile strain of 2050 µÆ 3× a week for five weeks with the contralateral limb as a non-loaded control. Half of the mice (equal number CKD and Con) received subcutaneous injections of 0.5 mg/kg raloxifene (RAL) 5× a week, and the other half remained untreated (UN). Mice were sacrificed at 31 weeks of age. Serum biochemistries were performed, and bi-lateral tibiae were assessed for microarchitecture, whole bone and tissue level mechanical properties, and composition including bone hydration. RESULTS: Regardless of intervention, BUN and PTH were higher in CKD animals throughout the study. In CKD, the combined effects of loading and RAL were quantified as lower cortical porosity and improved mechanical, material, and compositional properties, including higher matrix-bound water. Loading was generally responsible for positive impacts in cortical geometry and structural mechanical properties, while RAL treatment improved some trabecular outcomes and material-level mechanical properties and was responsible for improvements in several compositional parameters. While control animals responded positively to loading, their bones were less impacted by the RAL treatment, showing no deformation, toughness, or bound water improvements which were all evident in CKD. Serum PTH levels were negatively correlated with matrix-bound water. DISCUSSION: An effective treatment program to improve fracture risk in CKD ideally focuses on the cortical bone and considers both cortical porosity and matrix properties. Loading-induced bone formation and mechanical improvements were observed across groups, and in the CKD cohort, this included lower cortical porosity. This study highlights that RAL treatment superimposed on active bone formation may be ideal for reducing skeletal complications in CKD by forming new bone with enhanced matrix properties.


Assuntos
Fraturas Ósseas , Insuficiência Renal Crônica , Camundongos , Humanos , Masculino , Animais , Cloridrato de Raloxifeno/farmacologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Fraturas Ósseas/complicações , Água
11.
Nanotechnology ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640906

RESUMO

Graphene oxide nanosheet (GO) is a multifunctional platform for binding with nanoparticles and stacking with two dimensional substrates. In this study, GO nanosheets were sonochemically decorated with zinc oxide nanoparticles (ZnO) and self-assembled into a hydrogel of GO-ZnO nanocomposite. The GO-ZnO hydrogel structure is a bioinspired approach for preserving graphene-based nanosheets from van der Waals stacking. X-ray diffraction analysis (XRD) showed that the sonochemical synthesis led to the formation of ZnO crystals on GO platforms. High water content (97.2 %) of GO-ZnO hydrogel provided good property of ultrasonic dispersibility in water. Ultraviolet-visible spectroscopic analysis (UV-Vis) revealed that optical band gap energy of ZnO nanoparticles (~ 3.2 eV) GO-ZnO nanosheets (~ 2.83 eV). Agar well diffusion tests presented effective antibacterial activities of GO-ZnO hydrogel against gram-negative bacteria (E. coli) and gram-positive bacteria (S. aureus). Especially, GO-ZnO hydrogel was directly used for brush painting on biodegradable polylactide (PLA) thin films. Graphene-based nanosheets with large surface area are key to van der Waals stacking and adhesion of GO-ZnO coating to the PLA substrate. The GO-ZnO/PLA films were characterized using photography, light transmittance spectroscopy, coating stability, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopic mapping (EDS), antibacterial test and mechanical tensile measurement. Specifically, GO-ZnO coating on PLA substrate exhibited stability in aqueous food simulants for packaging application. GO-ZnO coating inhibited the infectious growth of E. coli biofilm. GO-ZnO/PLA films had strong tensile strength and elastic modulus. As a result, the investigation of antibacterial GO-ZnO hydrogel and GO-ZnO coating on PLA film is fundamental for sustainable development of packaging and biomedical applications.

12.
J Clin Med ; 13(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38610622

RESUMO

Background: Painful vaso-occlusive episodes (VOEs) are the hallmark of sickle cell disease (SCD) and account for frequent visits to the emergency department (ED) or urgent care (UC). Currently, the early administration of analgesics is recommended as initial management; however, there is a need for further understanding of the effect of prompt analgesics and hydration during VOEs. The objective of this study is to analyze the factors associated with the rate of hospital admission in the setting of time to intravenous (IV) analgesics and hydration. Method: This retrospective single-institution study reviewed adult and pediatric patients with SCD who presented with VOEs from January 2018 to August 2023. Results: Of 303 patient encounters, the rates of admission for the overall group, the subgroup which received IV hydration within 60 min of arrival, and the subgroup which received both IV analgesics and hydration within 60 min were 51.8%, 25.6% (RR = 0.46), and 18.2% (RR = 0.33), respectively. Further, factors such as gender and the use of hydroxyurea were found to be significantly associated with the rate of admission. Conclusions: This signifies the importance of standardizing the management of VOEs through the timely administration of IV analgesics and hydration in both adult and pediatric ED/UC.

13.
Materials (Basel) ; 17(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38612016

RESUMO

In the realm of cementitious materials, integrating nanoclay shows promise in enhancing properties relevant to additive manufacturing. This paper presents a novel mathematical model that combines simple empirical dissolution/nucleation Avrami-like kinetics with a thixotropic kinetics equation. To analyze the initial exothermic peak, two sets of the calculation parameter function are built to describe the exothermic rate as a function of time, following an exponential pattern. This allows for the prediction of the changes in cumulative heat and heat rate during hydration, considering different concentrations of nanoclay. In the rheological aspect, the relationship between shear stress, shear rate, and time is modeled as a combination of exponential dependencies. This enables the prediction of the variations in shear stress with one variable while holding the other constant (either time or shear rate). By integrating these aspects, this model effectively describes both the first exothermal peak and the rheological behavior during cement hydration with the inclusion of nanoclay. Validated against experimental results, these models demonstrate good accuracy (overall below 3% error), reliability, and applicability. The findings offer valuable insights into the thermal and rheological aspects of concrete printing, enabling informed design decisions for both scientific and industrial applications.

14.
Adv Colloid Interface Sci ; 327: 103145, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38615561

RESUMO

Friction and lubrication are ubiquitous in all kinds of movements and play a vital role in the smooth operation of production machinery. Water is indispensable both in the lubrication systems of natural organisms and in hydration lubrication systems. There exists a high degree of similarity between these systems, which has driven the development of hydration lubrication from biomimetic to artificial manufacturing. In particular, significant advancements have been made in the understanding of the mechanisms of hydration lubrication over the past 30 years. This enhanced understanding has further stimulated the exploration of biomimetic inspiration from natural hydration lubrication systems, to develop novel artificial hydration lubrication systems that are cost-effective, easily transportable, and possess excellent capability. This review summarizes the recent experimental and theoretical advances in the understanding of hydration-lubrication processes. The entire paper is divided into three parts. Firstly, surface interactions relevant to hydration lubrication are discussed, encompassing topics such as hydrogen bonding, hydration layer, electric double layer force, hydration force, and Stribeck curve. The second part begins with an introduction to articular cartilage in biomaterial lubrication, discussing its compositional structure and lubrication mechanisms. Subsequently, three major categories of bio-inspired artificial manufacturing lubricating material systems are presented, including hydrogels, polymer brushes (e.g., neutral, positive, negative and zwitterionic brushes), hydration lubricant additives (e.g., nano-particles, polymers, ionic liquids), and their related lubrication mechanism is also described. Finally, the challenges and perspectives for hydration lubrication research and materials development are presented.

16.
Appl Plant Sci ; 12(2): e11565, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638616

RESUMO

Premise: Methods to evaluate lichen thalli hydrophobicity have previously been described, but only recently has hydrophobicity been shown to be an important functional trait related to water regulation dynamics that could be used to predict future climate change effects. We describe a novel protocol to measure lichen thallus hydrophobicity that aims to be an easier and more affordable approach. Methods and Results: Our protocol requires only a micropipette, distilled water, a tripod, and a smartphone or camera. Hydrophobicity is inferred from multiple metrics associated with the absorption times of standardized droplets (initial and total absorption time). We used a data set of 93 lichen taxa with different growth forms and from different biomes and demonstrated that this method is well suited for capturing different levels of hydrophobicity, including very hydrophilic species. Conclusions: Our results show that this new protocol to measure lichen hydrophobicity is a rapid and low-cost method to assess an ecophysiologically based functional trait that can be used with almost no limitations, including in different climates, lichen species, and growth forms.


Premisa: En el pasado se han descrito métodos para evaluar la hidrofobicidad de los talos liquénicos, sin embargo, no fue hasta recientemente que se demostró la importancia de esta propiedad como rasgo funcional en relación a la dinámica de regulación hídrica de los talos, permitiendo utilizarla como herramienta para predecir futuros efectos del cambio climático. Describimos un nuevo protocolo para medir la hidrofobicidad de los talos liquénicos que pretende ser más fácil y asequible. Métodos y Resultados: Nuestro protocolo requiere solamente de una micropipeta, agua destilada, un trípode y un teléfono o una cámara. La hidrofobicidad es inferida a partir de múltiples métricas asociadas a los tiempos de absorción de gotas de un volumen estandarizado (tiempo de absorción inicial y tiempo de absorción total). Utilizamos datos de 93 taxones de líquenes con diferentes formas de crecimiento y provenientes de distintos biomas, lo que permitió demostrar que este método es adecuado para capturar diferentes niveles de hidrofobicidad, incluyendo a especies altamente hidrofílicas. Conclusiones: Nuestros resultados muestran que la medición de la hidrofobicidad de los talos es un método rápido y de bajo costo que permite evaluar un rasgo funcional basado en la ecofisiología de líquenes y que puede ser utilizado prácticamente sin limitaciones, incluyendo en diferentes climas, especies y formas de crecimiento.

17.
Nanomicro Lett ; 16(1): 177, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647738

RESUMO

Reversible protonic ceramic cells (RePCCs) hold promise for efficient energy storage, but their practicality is hindered by a lack of high-performance air electrode materials. Ruddlesden-Popper perovskite Sr3Fe2O7-δ (SF) exhibits superior proton uptake and rapid ionic conduction, boosting activity. However, excessive proton uptake during RePCC operation degrades SF's crystal structure, impacting durability. This study introduces a novel A/B-sites co-substitution strategy for modifying air electrodes, incorporating Sr-deficiency and Nb-substitution to create Sr2.8Fe1.8Nb0.2O7-δ (D-SFN). Nb stabilizes SF's crystal, curbing excessive phase formation, and Sr-deficiency boosts oxygen vacancy concentration, optimizing oxygen transport. The D-SFN electrode demonstrates outstanding activity and durability, achieving a peak power density of 596 mW cm-2 in fuel cell mode and a current density of - 1.19 A cm-2 in electrolysis mode at 1.3 V, 650 °C, with excellent cycling durability. This approach holds the potential for advancing robust and efficient air electrodes in RePCCs for renewable energy storage.

18.
Chemistry ; : e202303483, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656538

RESUMO

Clathrate hydrates are among the most intensively studied H-bond inclusion compounds. Despite the broad definition for this class of compounds, their meaning commonly refers to closed polyhedral nanocages that encapsulate small guest molecules. On the other hand, larger solutes enforce another type of encapsulation because of the solute size effect. Herein, we report a series of structures containing various molecules encapsulated by intercalated water layers constructed of polycyclic moieties of L4(4)8(8) topology. We parametrized the corrugation of individual layers and characterized interactions governing their formation. We suggested which could be categorized as two-dimensional clathrates based on the character of intra-layer interactions and effects observed between entrapped molecules and water-based intercalators.

19.
Clin Cosmet Investig Dermatol ; 17: 581-591, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495912

RESUMO

Purpose: Collagen supplements are rising in the market as collagen has been demonstrated to be an important protein in the human aging process. Also, it is safe and easily absorbed in the body. Hence the aim of this study was to examine the effectiveness and safety of a collagen and antioxidant-rich treatment compared to a placebo in relation to various skin and hair indicators in healthy adult human subjects. Patients and Methods: Forty healthy adult non-pregnant/non-lactating women (aged 38-50 years) provided their informed consent in writing before their participation. Skin Radiance Collagen (SRC) treatment and a placebo were assessed for efficacy before application on Day 1, and post-application on Days 28 and 56, to measure changes in skin elasticity, hydration, brightness, pigmentation; texture, wrinkles, dryness, smoothness, fine lines, changes in the crow's feet region; as well as hair strength and hair fall. Results: It was observed after 56 days that therapy with SRC, compared to placebo, produced a substantial effect on reduction of wrinkle depth and fine lines by 48.11% and 39%, respectively, with p-value <0.01 in the test group. There was a 15.69% improvement in skin hydration observed and 28% reduction in hair fall with p-value <0.01. Conclusion: SRC, a combination of collagen with hyaluronic acid (HA), biotin, and vitamins C and E, showed a significant improvement in skin and hair health, including improvements in skin elasticity, skin hydration, reduction in crow's feet area wrinkles and fine lines, hair fall, and decrease in roughness, leading to improved skin texture. Vitamin C in the formulation also acts as a collagen builder for the body and helps in preventing oxidative stress in the body. The test treatment SRC was found to be efficacious and safe in healthy human adult subjects.

20.
Alzheimers Dement (Amst) ; 16(1): e12528, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38496720

RESUMO

Many people dread prolonged dying with suffering in the terminal illness, advanced dementia. To successfully facilitate a timely dying, advance directives must be effective and acceptable. This article considers whether authorities, including treating physicians, can accept as moral, the effective intervention that ceases caregivers' assistance with oral feeding and hydrating. The article presents eight criticisms and "alternate views" regarding ceasing assisted feeding/hydrating. It draws on perspectives from clinical medicine, law, ethics, and religion. The conflict is between (A) people's core beliefs that reflect cultural norms and religious teachings regarding what is moral versus (B) patients' autonomous right of self-determination and claim right to avoid suffering. The article presents each side as strongly as possible. Accepting the intervention as moral could allow patients a peaceful and timely dying from patients' underlying disease. Confidence in future success can deter patients and their surrogates from considering a hastened dying in earlier stages of dementia.

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