Weight Distribution Research Articles

KOMPOSISI UKURAN DAN POLA PERTUMBUHAN IKAN CAKALANG (Katsuwonus pelamis) DI PERAIRAN KEPULAUAN TANIMBAR

Skipjack tuna (katsuwonus pelamis) is a fishery resource that has economic value which is in great demand and is utilized with various fishing tools and methods. This research aims to describe the skipjack tuna fishing unit using trolling rods, and analyze the distribution of length and weight of skipjack tuna in the waters of the Tanimbar Islands. The research was carried out from February to April 2024 in the waters of the Tanimbar Islands. Data collected through observation and interviews as well as practice of the fishing process, catches were measured by total length and the relationship between length and weight, then analyzed descriptively qualitatively, using the Sturges formula and length and weight. The results of the research show that the type of equipment and fishing method operated in the form of multiple hand line, and skipjack tuna caught in the waters of the Tanimbar Islands are in the size of 29.5-75 cm TL where the percentage of presence shows that the size of 49-52 cm dominates, namely 35. 62% with negative allometric skipjack tuna growth patterns.

Fabrication of Hybrid Coated Microneedles with Donepezil Utilizing Digital Light Processing and Semisolid Extrusion Printing for the Management of Alzheimer's Disease.

Microneedle (MN) patches are gaining increasing attention as a cost-effective technology for delivering drugs directly into the skin. In the present study, two different 3D printing processes were utilized to produce coated MNs, namely, digital light processing (DLP) and semisolid extrusion (SSE). Donepezil (DN), a cholinesterase inhibitor administered for the treatment of Alzheimer's disease, was incorporated into the coating material. Physiochemical characterization of the coated MNs confirmed the successful incorporation of donepezil as well as the stability and suitability of the materials for transdermal delivery. Optical microscopy and SEM studies validated the uniform weight distribution and precise dimensions of the MN arrays, while mechanical testing ensured the MNs' robustness, ensuring efficient skin penetration. In vitro studies were conducted to evaluate the produced transdermal patches, indicating their potential use in clinical treatment. Permeation studies revealed a significant increase in DN permeation compared to plain coating material, affirming the effectiveness of the MNs in enhancing transdermal drug delivery. Confocal laser scanning microscopy (CLSM) elucidated the distribution of the API, within skin layers, demonstrating sustained drug release and transcellular transport pathways. Finally, cell studies were also conducted on NIH3T3 fibroblasts to evaluate the biocompatibility and safety of the printed objects for transdermal applications.

Antioxidant Marine Hydrolysates Isolated from Tuna Mixed Byproducts: An Example of Fishery Side Streams Upcycling.

The aim of this research is to propose simple and scalable processes to obtain bioactive peptides extensively hydrolyzed starting from a tuna mixed biomass. The upcycling of this powdered biomass is challenging since it comes from the unsorted industrial side streams of the tuna canning process (cooked residues from fillet trimming) after a patented mild dehydration useful for preventing its degradation until its exploitation. Two different protocols were proposed, with and without the inclusion of an exogenous enzyme (Enzymatic-Assisted Extraction, EAE), with no relevant differences in yields (24% vs. 22%) and a comparable amino acid composition. Nevertheless, the former protocol (with EAE) provided peptides with an average molecular weight of 1.3 kDa, and the second one (without EAE) provided peptides with an average molecular weight of 2.2 kDa. The two corresponding types of tuna protein hydrolysates (Enzymatic Hydrolysates (EH) and Non-Enzymatic Hydrolysates (NEH)) were characterized by proximate compositions, pH, color profile, amino acid analysis, FTIR spectra, and molecular weight distribution. In addition, several biological analyses were performed to assess their potential use as nutraceutical supplements: special attention has been paid to antioxidant activity using three different methods to quantify it. EH showed the most promising antioxidant activity which could be exploited also in other fields (e.g., biomaterials, cosmetics).

A highly efficient oxygen tolerant visible-light mediated RAFT polymerization

Recently, oxygen-tolerant reversible addition-fragmentation chain transfer (RAFT) polymerization has attracted increasing attention in polymer chemistry. Inspired by the monomers containing glycol ethers group have high polymerization rates and even achieved a desirable oxygen tolerance. Herein, we proposed a simple, effective, low-cost, and eco-friendly strategy to accomplish the oxygen-tolerant visible-light activated RAFT polymerization of acrylates and acrylamides in a mixed solution of glycol ether and water at ambient temperature. This photo-mediated RAFT polymerization does not require additives, prior deoxygenation, or inert gas protection. The acrylates and acrylamides with high conversion under irradiation for 2 h, and the resulting polymers were narrow unimodal and narrow molecular weight distributions (PDI<1.3). In addition, the “living” and well-controlled behaviors of this oxygen-tolerant photo-mediated RAFT polymerization were demonstrated through water content in solvents, headspace, initial concentration of monomers, various monomers, chain lengths, light ON/OFF experiment, and high-end group fidelity of block copolymers. This RAFT polymerization also opens up a wide avenue for the industrial production of functional polymeric materials via an in situ chain extension strategy. These results indicate that the mixed solution of glycol ethers and water are effective green media for promoting photo-mediated RAFT polymerization without additives or tedious degassing processes.

Effects of molecular structure and temperature field on the crystallization behavior of poly(tetrafluoroethylene-co-perfluoroalkylvinyl ether)

Despite the wide industrial application of poly(tetrafluoroethylene-co-perfluoroalkylvinyl ether) (PFA) in semiconductor processing, its crystallization behavior has little been studied. In this work, three PFA resins with similar molecular weight but different comonomer content and distribution were synthetized. Then the non-isothermal crystallization kinetics and crystalline structures were studied by differential scanning calorimetry, polarizing optical microscopy, and X-ray diffraction systematically. It is found that the incorporation of comonomers destroys the chain regularity and reduces the crystallizability of PFA thermodynamically, while the comonomer insertion improves the chain flexibility to accelerate the crystal growth dynamically. When the comonomer content of PFA is low, both the nucleation and growth rates are quite fast, which is favorable for the formation of spherulite. As the comonomer content increases or distribute uniformly in the chain, the nucleation rate declines notably and the side groups distort the crystal cell to increase the spacing of [100] plane. Moreover, two-dimensional growth mode is dominant to form bundle-like structure when crystallizing at slow cooling, where nucleation is suppressed by growth. But three-dimensional symmetrical spherulite can be activated and perfected at high cooling rate due to the initiation of substantial nucleation sites. This unique crystallization behavior is opposite to that of conventional polymers, providing a guidance for the polymerization and processing of PFA.

The Comparative Analysis of Peptides in Enteral Nutrition Products and Foods for Special Medical Purposes.

Enteral nutrition (EN) and foods for special medical purposes (FSMPs) can be used to meet the specific nutritional needs of patients. There are multiple types of EN products and nutritionally complete FSMPs on the market. The peptides in these products are important nutritional components, while their presence in different products remains unclear. To provide better clinical guidelines, we analyzed and compared the molecular weight (MW) distribution, types, and quantities of peptides and bioactive peptides of two EN products (liquid products) and two FSMPs with nutritionally complete formulas (powder products). Our results showed that each product had a unique peptide profile. The two liquid products and one powder product (Samples 1-3) had a higher content of peptides. Sample 1 contained 75.60% peptides with an MW less than 375 Da and contained 95.21% peptides with an MW less than 1000 Da, being rich in short peptides. Sample 2 and 3 had high levels of peptides with MW values between 180 Da and 2000 Da. Additionally, Sample 4 contained high levels of proteins, containing 69.18% peptides with MW values larger than 10,000 Da. Further, Sample 1 had more bioactive dipeptides and Sample 2 had more long bioactive peptides. Our results suggest that peptides in different EN and FSMP products are very different and should be evaluated in more detail. This will provide valuable information for clinical medical professionals, help them to guide patients with different physiological conditions better, and ultimately benefit patients.

Ionic Liquid-Based Extraction of Fulvic-like Substances from Wood Sawdust: Reproducing Unique Biological Activities of Fulvic Acids Using Renewable Natural Sources.

Fulvic acids (FAs) have been commercially used in cosmetics and agronomy due to their unique biological activities, such as plant stimulation and anti-inflammatory effects. However, the extraction sources of FAs, such as peat, are currently limited. Consequently, new extraction methods using renewable resources need to be developed, while reproducing the biological functions. Here, ionic liquids (ILs) effectively extracted fulvic-like substances (FLSs) from wood sawdust. The overall molecular weight distributions of FLSs were similar to those of commercial FAs, and key organic groups (e.g., aromatic, phenolic, and methoxy groups) were also found to be shared between commercial FAs and FLSs. Detailed compositional analysis revealed by high-resolution mass spectrometry showed that the extracts contain both lignin-like and lipid-like molecules, while commercial FAs are biased toward lignin-like and carbohydrate-like molecules. FLSs generally showed better and similar performance in radical scavenging activity against ABTS+· and H2O2. Fibroblast proliferation and lettuce growth enhancements were also observed with the extract containing 1-ethyl-3-methylimidazolium acetate and triethylammonium hydrogen sulfate, respectively, which performed better than commercial FAs. Immunofluorescence staining of in vitro human follicle dermal papilla cells supports that coexpression of hair growth-related proteins can be accelerated with FLSs, and this effect was further evidenced by in vivo mouse model experiments. Finally, the reusability of ILs in the extraction process was confirmed by analyzing the structural features of FLSs from each recycling. Our findings indicate that ILs are useful for obtaining biologically functional fulvic analogs from renewable plant sources.

Effects of ultrasonic waves of different powers on the physicochemical properties, functional characteristics, and ultrastructure of bovine liver peptides

In recent years, ultrasound has emerged as a widely used technology for modifying proteins/peptides. In this study, we focused on the intrinsic mechanism of ultrasound-induced modification of bovine liver peptides, which were treated with ultrasound power of 0, 100, 200, 300, 400, and 500 W, and their physicochemical and functional properties, as well as ultrastructures, were investigated. The results show that ultrasound mainly affects hydrogen bonding and hydrophobic interactions to change the conformation of proteins and unfolds proteins through a cavitation effect, leading to an increase in biological activity. Fourier infrared spectroscopy showed that ultrasound inhibited the formation of hydrogen bonds and reduced intermolecular cross-linking. Molecular weight distribution showed that the antioxidant components of bovine liver polypeptides were mainly concentrated in fractions of 500–1,000 Da. Maximum values of ABTS (82.66 %), DPPH (76.02 %), chelated iron (62.18 %), and reducing power (1.2447) were obtained by treating bovine liver polypeptides with 500 W ultrasound. Combined with the scanning electron microscopy results, with the intervention of ultrasound, the impact force generated by ultrasonication may lead to the loosening of the protein structure, which further promotes the release of antioxidant peptides, and these findings provide new insights into the application of ultrasound in the release of antioxidant peptides from bovine liver.

Exploring the curing kinetics of Acrolein-Pentaerythritol resin: Impact of molecular weight and molecular weight distribution on cure behavior

Curing kinetics are crucial for designing and optimizing the process parameters of a resin. This study examines the non-isothermal curing kinetics of acrolein-pentaerythritol (APE) resins, focusing on the impact of molecular weight (MW) and molecular weight distribution (MWD) on their cure behavior. Kinetic parameters were determined using isoconversional and combined kinetic analysis methods through microcalorimeter measurements. The findings suggest that the cure process follows the nucleation and growth models (Avrami−Erofeev equation), with an activation energy of 72.2 kJ/mol. A comparison of two APE resins with different molecular weights and molecular weight distributions reveals that higher MW components expedite the initial curing reaction but impede the main curing process, leading to extended curing durations. This study provides valuable insights into the curing kinetics of APE resin and the influence of MW and MWD, contributing to the reliable and reproducible production of composite parts.

Terpolymerization of Ethylene with Hexene and Styrene Derivatives by Half-Sandwich Scandium Catalyst.

The terpolymerization of ethylene with hexene and styrene derivatives was achieved with a rare earth metal catalyst (C5Me4SiMe3)Sc(CH2C6H4NMe2-o)2 to prepare functional polyethylene. The catalyst system exhibited high activity in the terpolymerization of ethylene with hexene and amine-substituted styrene, affording terpolymers a moderate molecular weight and a unimodal molecular weight distribution. In addition, the comonomer content of the terpolymers can be controlled by changing the feeding ratio of monomers. The aliphatic region of the 13C NMR spectra reveals that the structural units of the comonomers are separately incorporated into the polyethylene backbone. Terpolymers containing styrene derivatives exhibit enhanced tensile strength and significantly improve hydrophilic properties.

Effects of ACLY Inhibition on Body Weight Distribution: A Drug Target Mendelian Randomization Study.

Background: Adenosine triphosphate-citrate lyase (ACLY) inhibition has proven clinically efficacious for low-density lipoprotein cholesterol (LDL-c) lowering and cardiovascular disease (CVD) risk reduction. Clinical and genetic evidence suggests that some LDL-c lowering strategies, such as 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) inhibition with statin therapy increase body weight and the risk of developing type 2 diabetes mellitus (T2DM). However, whether ACLY inhibition affects metabolic risk factors is currently unknown. We aimed to investigate the effects of ACLY inhibition on glycaemic and anthropometric traits using Mendelian randomization (MR). Methods: As genetic instruments for ACLY inhibition, we selected weakly correlated single-nucleotide polymorphisms at the ACLY gene associated with lower ACLY gene expression in the eQTLGen study (N = 31,684) and lower LDL-c levels in the Global Lipid Genetic Consortium study (N = 1.65 million). Two-sample Mendelian randomization was employed to investigate the effects of ACLY inhibition on T2DM risk, and glycaemic and anthropometric traits using summary data from large consortia, with sample sizes ranging from 151,013 to 806,834 individuals. Findings for genetically predicted ACLY inhibition were compared to those obtained for genetically predicted HMGCR inhibition using the same instrument selection strategy and outcome data. Results: Primary MR analyses showed that genetically predicted ACLY inhibition was associated with lower waist-to-hip ratio (β per 1 standard deviation lower LDL-c: -1.17; 95% confidence interval (CI): -1.61 to -0.73; p < 0.001) but not with risk of T2DM (odds ratio (OR) per standard deviation lower LDL-c: 0.74, 95% CI = 0.25 to 2.19, p = 0.59). In contrast, genetically predicted HMGCR inhibition was associated with higher waist-to-hip ratio (β = 0.15; 95%CI = 0.04 to 0.26; p = 0.008) and T2DM risk (OR = 1.73, 95% CI = 1.27 to 2.36, p < 0.001). The MR analyses considering secondary outcomes showed that genetically predicted ACLY inhibition was associated with a lower waist-to-hip ratio adjusted for body mass index (BMI) (β = -1.41; 95%CI = -1.81 to -1.02; p < 0.001). In contrast, genetically predicted HMGCR inhibition was associated with higher HbA1c (β = 0.19; 95%CI = 0.23 to 0.49; p < 0.001) and BMI (β = 0.36; 95%CI = 0.23 to 0.49; p < 0.001). Conclusions: Human genetic evidence supports the metabolically favourable effects of ACLY inhibition on body weight distribution, in contrast to HMGCR inhibition. These findings should be used to guide and prioritize ongoing clinical development efforts.

Collagen-rich liver-derived extracellular matrix hydrogels augment survival and function of primary rat liver sinusoidal endothelial cells and hepatocytes

Liver sinusoidal endothelial cells (LSECs) are key targets for addressing metabolic dysfunction-associated steatotic liver disease (MASLD). However, isolating and culturing primary LSECs is challenging due to rapid dedifferentiation, resulting in loss of function. The extracellular matrix (ECM) likely plays a crucial role in maintaining the fate and function of LSECs. In this study, we explored the influence of liver-ECM (L-ECM) on liver cells and developed culture conditions that maintain the differentiated function of liver cells in vitro for prolonged periods. Porcine liver-derived L-ECM, containing 34.9 % protein, 0.045 % glycosaminoglycans, and negligible residual DNA (41.2 ng/mg), was utilized to culture primary rat liver cells in generated hydrogels. Proteomic analyses and molecular weight distribution of proteins of solubilized L-ECM revealed the typical diverse ECM core matrisome, with abundant collagens. L-ECM hydrogels showed suitable stiffness and stress relaxation properties. Furthermore, we demonstrated that collagen-rich L-ECM hydrogels enhanced LSECs' and hepatocytes' viability, and reduced the dedifferentiation rate of LSECs. In addition, hepatocyte function was maintained longer by culture on L-ECM hydrogels compared to traditional culturing. These beneficial effects are likely attributed to the bioactive macromolecules including collagens, and mechanical and microarchitectural properties of the L-ECM hydrogels.

Analysis of Fault Events in Rail Transit Vehicle Traction Systems Based on Knowledge Graph Reasoning

Fault text records provide detailed information on faults and handling steps, which are valuable for fault analysis. However, the different individuals’ recording styles can lead to ambiguities, and it is challenging to uncover potential fault associations in complex systems. To address these issues, this paper proposes a novel method for fault information extraction and analysis. Firstly, to tackle the problem of ambiguous boundaries between entities in fault texts, an integration algorithm is employed to accurately recognize fault entities considering contextual semantic features to establish fault knowledge graph (FKG). Then, a Relational Graph Convolutional Networks (RGCN) is improved with Graph Attention Networks (GAT) for sparse nodes caused by specific types of faults, to dynamically adjust the weight distribution of node learning, inferring potential links within the graph. The proposed method was validated using actual fault records from the traction system of rail transit vehicles, and contributes a reference for the mining and analysis of fault records in complex systems.

Structural characterization and physicochemical properties of grain amaranth starch

With potato starch (PS) and corn starch (CS) as the controls, the structure and physicochemical properties of grain amaranth starch (GAS) and its binding with dihydromyricetin were investigated in this study. The results indicated that GAS granules were small in size (3.21 ± 0.13 μm) and had a low amylose content (11.57 ± 0.91%). GAS exhibited low paste clarity, solubility, and swelling power, but demonstrated good freeze-thaw stability and resistance to retrogradation. Although the pasting temperature of GAS was high (75.88 ± 0.03 °C), its peak viscosity, breakdown viscosity, and setback viscosity were significantly lower than those of PS and CS. GAS was classified as A-type starch, with a high molecular weight and broad distribution (Mw, 3.96 × 107 g/mol; PDI, 2.67). For its chain length distribution, chain B1 had the highest proportion (50.09%), while chain B3 had the lowest proportion (13.50%). The complexation of GAS with dihydromyricetin effectively enhanced its ABTS and DPPH free radical scavenging capacities.

RAFT copolymerization of methyl methacrylate and di(ethylene glycol) methyl ether methacrylate in a hexylpyridinium ionic liquid

AbstractSmart polymers undergo significant physical or chemical changes in response to stimuli like temperature and pH. Achieving a narrow molecular weight distribution is crucial for their sensitivity. Reversible addition–fragmentation chain transfer (RAFT) in ionic liquids is an effective method for synthesizing such polymers due to its favorable kinetics and environmental benefits. Most studies use imidazolium ionic liquids, while pyridinium ionic liquids are less common despite their easy synthesis. This study reports the first successful RAFT copolymerization of di(ethylene glycol) methyl ether methacrylate (DEGMEMA) and methyl methacrylate in N‐hexylpyridinium hexafluorophosphate ([HPY][PF6]). Both linear and hyperbranched copolymers (Mn &gt; 25,000) with narrow molecular weight distribution were synthesized, showing observable temperature responses and biocompatibility. The linear copolymers had a desirable dispersity (Ð) of less than 1.10, while the hyperbranched copolymer had a Ð of 2.034. The lower critical solution temperatures (LCSTs) of the copolymers were close to or below the LCST of PDEGMEMA (26°C). This study indicates that pyridinium ionic liquids can be explored as a suitable solvent for synthesizing methacrylate‐based smart polymers.

The scope of alum coagulation-flocculation assisted by slaked lime for the treatment of industrial wastewater containing highly concentrated Acid Black 194 dye. Optimization, molecular weight distribution and toxicity analysis

This work evaluated the capacity of the alum coagulation-flocculation (C–F) process, assisted by slaked lime, for the treatment of industrial textile wastewater (ITWW) containing highly concentrated Acid Black 194 dye. By optimizing the operating conditions ([Alum] = 16.09 g/L, [Ca(OH)2] = 5.16 g/L) through experimental design, response surface methodology, and multi-objective optimization analysis, the C–F process removed 95 % of the dye, 63 % of the COD, 60 % of the TOC, and 94 % of the total Cr concentration, with a total operating cost of 5.99 USD/m3. This improved the biodegradability index (from 0.20 to 0.26), the COS parameter (from 0.14 to 2.46), and the toxicity of the effluent (LC50 for Artemia salina increased from 15.16 mg/L to 56.7 mg/L). The calcium hardness and total hardness were also reduced by 40 % and 44 %, respectively. The C–F supernatant was composed mainly of molecules with molecular weights less than and equal to 10 kDa. An LC-MS spectral analysis revealed the presence of four residual aromatic and recalcitrant compounds in the C–F supernatant, indicating that its further treatment is required before it can be safely discharged or recycled for industrial purposes. The alum C–F process, assisted by slaked lime, demonstrated greater performance, surpassing the individual processes in effectiveness and efficiency, and confirming their synergetic effect. The alum process alone (16.09 g/L) achieved a 37 % reduction COD and 91 % color removal, at a total cost of 4.49 USD/m3. The lime process alone (5.16 g/L) achieved a 37 % COD reduction and 64 % color removal, at a total cost of 1.36 USD/m3.

Jeffamine-based diblock copolymer nanoparticles via reverse sequence polymerization-induced self-assembly in aqueous media

Jeffamines® are commercially available amine-capped poly (alkylene oxides) that have been used for various applications. In this study, a weakly hydrophobic monoamine-capped propylene oxide-rich Jeffamine® (M2005) is derivatized to introduce a trithiocarbonate end-group via amidation. This precursor is then dissolved using N,N′-dimethylacrylamide (DMAC), 2-(N-acryloyloxy)ethyl pyrrolidone (NAEP) or N-acryloylmorpholine (NAM) as a co-solvent to produce a concentrated aqueous reaction mixture containing 20 % w/w water. Subsequently, reversible addition-fragmentation chain transfer (RAFT) polymerization is used to prepare Jeffamine®-core diblock copolymer nanoparticles by reverse sequence polymerization-induced self-assembly (PISA). At intermediate conversion, additional degassed water is added and each polymerization continues to almost full conversion (>99 %) within 4 h at 60 °C, resulting in a 10–20 % w/w aqueous dispersion of sterically-stabilized Jeffamine®-core nanoparticles. Efficient chain extension of the Jeffamine® precursor is achieved in most cases and relatively narrow molecular weight distributions are obtained (Mw/Mn < 1.30) as judged by GPC analysis. Transmission electron microscopy studies confirm a polydisperse spherical morphology and dynamic light scattering studies report hydrodynamic diameters ranging from 145 to 312 nm. Finally, aqueous electrophoresis studies indicate essentially neutral nanoparticles over a wide range of solution pH, as expected for the three types of non-ionic steric stabilizer chains selected for this study.

Central limit theorem in disordered Monomer‐Dimer model

AbstractWe consider the disordered monomer‐dimer model on general finite graphs with bounded degrees. Under the finite fourth moment assumption on the weight distributions, we prove a Gaussian central limit theorem for the free energy of the associated Gibbs measure with a rate of convergence. The central limit theorem continues to hold under a nearly optimal finite ‐moment assumption on the weight distributions if the underlying graphs are further assumed to have a uniformly subexponential volume growth. This generalizes a recent result by Dey and Krishnan who showed a Gaussian central limit theorem in the disordered monomer‐dimer model on cylinder graphs. Our proof relies on the idea that the disordered monomer‐dimer model exhibits a decay of correlation with high probability. We also establish a central limit theorem for the Gibbs average of the number of dimers where the underlying graph has subexponential volume growth and the edge weights are Gaussians.

Polysaccharides from Seedless Chestnut Rose (Rosa sterilis) Fruits: Insights into Innovative Drying Technologies and Their Structural Characteristics, Antioxidant, Antiglycation, and α-Glucosidase Inhibitory Activities.

The selection of an optimal drying method is essential for extending the shelf life and enhancing the quality of Rosa sterilis fruits. This study investigated the effects of both innovative (microwave vacuum drying and infrared drying) and traditional (freeze-drying and hot air drying) techniques on the structural characteristics and bioactivities of polysaccharides from R. sterilis fruits (RSPs). Four different RSPs were obtained from fruits dried using these methods. Results demonstrated that the structural characteristics and bioactivities of RSPs varied significantly with the drying method. Notable differences were observed in extraction yield, total sugar, uronic acid content, monosaccharide molar ratios, molecular weight distribution, particle size, thermal stability, and microstructures of RSPs. Despite these variations, the types of constituent monosaccharides and major glycosidic linkages remained consistent across all methods. Notably, RSPs obtained via microwave vacuum drying (RSPs-MVD) showed a higher uronic acid content and lower molecular weight, and exhibited stronger in vitro antioxidant, α-glucosidase inhibitory, and antiglycation activities. These findings suggest that microwave vacuum drying is an effective pre-drying technique for extracting RSPs, making them suitable as bioactive ingredients in functional foods and pharmaceuticals for managing diabetes mellitus and its complications.

Fabrication of flat and sizeable nanocellular polymethyl methacrylate (PMMA) foam with tunable thermal conductivity

AbstractPolymeric nanocell foam is a promising material that faces manufacturing challenges. Producing sizable and thick foams for properties testing has been challenging. This study aims to scale up and understand the foaming mechanism of nanocellular foams by controlling the saturation temperature, pressure, and molecular weight distribution of the matrix to fine‐tune the glass transition temperature of the polymer/gas mixture. The hot‐press foamed samples possess a 100 × 70 × 6 ~ 8 mm3 dimension and a cell size of less than 200 nm. Bimodal structures can also be created by controlling the critical processing parameters. Introducing 37% microcells into unimodal nanocellular foam reduced the relative density from 0.29 to 0.19. The thermal conductivity of the foams was tuned by controlling the cell size distribution. Unimodal nanofoams have the lowest thermal conductivity for foams of the same density due to the Knudsen effect and tortuosity. The measured thermal conductivity is in agreement with theoretical models.Highlights PMMA nanofoam with a dimension of 100 × 70 × 6–8 mm3 and cell size below 200 nm. The morphology of nanofoams was tuned to be unimodal and bimodal. The foam density of the bimodal nanofoams was lowered below 0.238 g/cm3. The thermal conductivity of foams was tuned by controlling the cell structure.