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The need for green thermal insulation materials, such as biopolymer aerogels, has become increasingly critical in the face of escalating environmental concerns and the urgent push toward sustainable practices. The unique characteristics of biopolymer aerogels, coupled with their environmental benefits, position them as potential disruptors in the insulation industry. As research continues, addressing challenges and refining fabrication techniques will likely lead to wider adoption of these materials, contributing to a greener and more energy‐efficient built environment. This review presents the latest developments concerning the properties and versatile applications of biopolymer‐based thermal insulators as a new type of green materials. It comprehensively examines the fundamental principles of thermal insulation, factors that influence its efficacy, and the compatibility and mechanisms underlying bioaerogels within this context. The review also addresses the latest works about the utilization of different biopolymer aerogels in different thermal insulation applications and critically assesses the obstacles currently faced by biopolymer‐based aerogels and elucidates potential avenues for future advancement. Highlights: Biopolymer aerogels offer a sustainable alternative in insulation.Challenges in production limit current aerogel adoption rates.Latest advancements highlight aerogels' versatile insulation applications.Future research aims to enhance biopolymer aerogel technology and use. [ABSTRACT FROM AUTHOR]

This study investigates the development and characterization of chitosan, gelatin, and chitosan/gelatin (Chi/Gel) bioaerogel composites through a facile and eco‐friendly approach. The goal is to optimize their structural and functional properties for potential environmental and biomedical applications. Direct freezing and lyophilization approach were used to prepare the aerogels, the focus was on investigating the effects of blending ratios on the density, porosity, surface area, and water absorption capabilities of the aerogels. The results show that Chi/Gel 60/40 composition achieved an optimal balance of structural robustness and functional performance, characterized by a moderate density of 74.2 mg/cm3, the highest porosity among the samples at 93.5%, an impressive surface area of 184.8 m2/g, and a water absorption capacity of 28.8 g/g. These results suggest that the synergistic effect of chitosan and gelatin at specific ratios significantly enhances the overall properties of the material. Our findings suggest that Chi/Gel bioaerogels, especially the 60/40 composite, hold great promise for diverse applications. Highlights: All Gelatin/Chitosan bioaerogels exhibited high porosity and low density.The Chi/Gel 60/40 mix achieved the highest porosity and surface area.Highest water adsorption was observed in the Chi/Gel 60/40 composite.Synergistic effects enhanced properties of the Gelatin/Chitosan scaffolds. [ABSTRACT FROM AUTHOR]

This study explores the utilization of Spent Coffee Grounds (SCG), a residual product of the coffee industry, as a microfiller reinforcement in Poly‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate (PHBV) biopolymer composites at varying concentrations (1%, 3%, 5%, and 7%). Melt compounding via a twin‐screw extruder and subsequent compression molding were employed in the fabrication process. The SCG microfiller, with particle diameters ranging from 1.11 to 1.28 μm, exhibited a significant negative charge (zeta potential: −20 mV). Hydrophobicity increased up to 5% filler concentration, as indicated by higher water contact angles, but diminished at highest concentration likelihood of agglomeration of the spent coffee grounds within the biopolymer matrix. The addition of SCG enhanced overall mechanical properties, particularly at a 5% filler concentration. Field Emission Scanning Electron Microscopy (FE‐SEM) and Atomic Force Microscopy (AFM) confirmed the successful incorporation of SCG microfiller, improving structural characteristics. Schematic drawings illustrated the interphase bonding of microfiller and matrix. However, properties diminished at the highest filler content (7%) due to coffee grounds' agglomeration. Despite this, SCG incorporation enhanced functional properties, making the biopolymer composite a promising material for sustainable packaging and various applications. Highlights: Enhancement of properties of spent coffee grounds in PHBV biocomposites.Characterization of Biocomposites for multifunctional properties.Fracture and 2D analysis of the tensile fractured surface of biocomposites.A promising material for sustainable and biodegradable packaging. [ABSTRACT FROM AUTHOR]

A sustainable and environmentally conscious approach was employed to create a cellulose nanofiber (CNF) bioaerogel. This modified technique was used for its affordability and eco‐friendly nature, involved the use of reduced concentrations of NaOH solution (ranging from 0 to 0.5 M) to disperse the CNFs. The process included mixing, freezing, neutralizing, and freeze‐drying, ultimately resulting in well‐structured 3D bioaerogels. The concentration of NaOH had a significant impact on the properties of the bioaerogels. The density of the aerogels increases with higher concentration of NaOH. All treated aerogels exhibited impressive water resistance and maintained their structural integrity when exposed to water, indicating promising practical applications. This enhanced structural integrity is attributed to CNF chain rearrangement, facilitated by CNF swelling, dissolution in NaOH, and homogenization. FTIR and XRD analyses provided insight into the transition from cellulose I to cellulose‐II in the bioaerogel structure. These findings contribute to the development of eco‐friendly bioaerogels for environmentally conscious applications. Further research is needed to gain a deeper understanding of the process and to optimize conditions for specific bioaerogel properties. [ABSTRACT FROM AUTHOR]

The production of kenaf bast cellulose nanofibrillated fiber (CNF) using a combined method of supercritical carbon dioxide (SCCO2) and high‐pressure homogenization as the reinforcement with biopolymer were studied. The obtained CNF was used as reinforcement in polylactic acid using the solvent casting method. The obtained CNF were verified using TEM and FTIR analysis to approve the effectiveness of the technique. The dispersion of kenaf bast cellulose nanofibrillated fiber in modified PLA was studied with scanning electron microscopy and atomic force microscopy. Further characterization, such as, mechanical, thermal, and wettability properties of the composite was also analyzed. The TEM and FTIR confirmed the formation of nanofiber, and the FTIR result showed a typical bond present in cellulose nanofibrillated fiber. The SEM and AFM showed good dispersion of the kenaf bast cellulose nanofibrilated fiber in PLA. The mechanical and thermal properties of the composite were significantly improved compared with the neat PLA. The wettability showed that the addition of CNF increased the hydrophilicity of the sample. The production of CNF through combine methods displayed comparable properties to those produced from conventional methods and the CNF preparation method in this study is simplified and adaptable for potential industrial application. [ABSTRACT FROM AUTHOR]

Summary: Background: The importance of a life course approach to childhood obesity has been emphasized; however, few studies can prospectively investigate relationships in three‐generation families. Objective: To prospectively investigate the relationship between grandparental and grandchild waist circumference (WC) at ages 5 and 9 down maternal and paternal lines. Methods: At baseline in the Lifeways Cross‐Generation Cohort, 1094 children were born to 1082 mothers; 585 were examined at age 5 and 298 at age 9. Of the total 589 children with measured WC, data were also available from 745 grandparents. Child WC was standardized for age and sex, and theory‐based hierarchical linear regression was used. Results: Maternal grandmother (MGM) WC was predictive of grandchild WC at both time points. At age 5, grandchild's standardized birth weight (B = 0.266, p = 0.001), mother's means tested eligibility for free medical care (B = 1.029, p = 0.001) and grandchild seeing maternal grandparents daily (B = 0.312, p = 0.048) were significant alongside MGM WC (B = 0.015, p = 0.019). At age 9, only MGM WC (B = 0.022, p = 0.033) and mother's WC (B = 0.032, p = 0.005) were significant. Mediation analysis with mother's WC showed significant direct relationship of MGM and grandchild WC. Conclusions: This prospective cross‐generational cohort shows consistent patterns of association between MGM and grandchild WC, not seen in other grandparental lineages. [ABSTRACT FROM AUTHOR]

Objectives: According to clinical and comissioning guidelines for chronic rhinosinusitis (CRS), patients being referred to secondary care should have failed primary medical treatment with nasal douching (ND) and intranasal corticosteroids (INCS). The study objectives were to identify the rate of specific medical therapy in CRS patients and establish any differences in medication use, for both CRS and associated medical conditions, between CRS phenotypes. Design and setting: Case–control study in a secondary care setting. Methods: Participant‐reported study‐specific questionnaire capturing free text data on current medication use at the time of study entry. Qualitative interviews with 21 participants also explored their experience of CRS and its management. Particpants: Patients both without (CRSsNPs) and with polyps (CRSwNPs). Main outcome measures: Reported use of CRS‐related and non‐related medications. Results: Within a total of 1243 CRS participants, current INCS usage was low (18% in CRSwNPs, 12% in CRSsNPs); ND was being performed by only 1% of all participants. Bronchodilators and inhaled corticosteroids use was significantly higher in CRSwNPs participants (P < .0001). Antidepressant use was significantly higher in CRSsNPs (14% vs 7%, P < .0002). There were no significant regional variations in rates of INCS use, nor any significant influence of social deprivation. Conclusions: The current use of baseline medical therapy in CRS appears to be very low, representing a combination of poor patient compliance, possible ineffectiveness of treatment and a lack of familiarity with current guidelines amongst general practitioners and some ENT specialists. Work is needed to disseminate guidelines to all practitioners involved and reduce unnecessary burden on existing healthcare resources for this common condition by ensuring timely referral and definitive management. [ABSTRACT FROM AUTHOR]

In radar antennas, asymmetric side lobes are useful, where undesired signals such as noise and ground clutter should be minimized. Also, for practical implementation, the feeding network of such antennas should be efficiently designed. In this paper, a simple analytical method for synthesizing asymmetric side lobe pattern with a wide-angle steered null in the nonuniformly excited linear arrays is presented. In this method, the difference in the side lobe levels on both sides of the main beam is achieved by varying just the phase excitations of the two-edge elements. The major novelty of this paper lies in the fact that the required asymmetric side lobe pattern can be achieved by changing a single phase shifter resulting in a simple feeding network. [ABSTRACT FROM AUTHOR]

Highlights from the article: 5G mobile communications technology will bring new experiences to industry and society, including higher data rates or greater capacity, higher bandwidth, increased security, and lower latency. Another paper discusses the direction finding problem in a background of unknown nonuniform noise using nested arrays, where a novel gridless direction finding method is proposed via the low-rank covariance matrix approximation. The search-free DOA estimation method is then utilized to perform the parameter estimation. Moreover, results indicate that the proposed method gives a more accurate DOA estimation of both the nonuniform noise and off-grid cases compared to a state-of-the-art DOA estimation algorithm.

The purpose of this research is to investigate the influence of different powder loadings of 316L stainless steel (SS) powders on rheological behavior of feedstocks required for low pressure powder injection molding (L-PIM) process. The main idea consists in development of various formulations by varying 316L SS powder contents in feedstocks and evaluating the temperature sensitivity of feedstock via flow behavior index and activation energy. For this purpose, the irregular shape, spherical shape, and combination of both shapes and sizes (bimodal approach) of 316L SS powders are compounded with wax based composite binder. Moreover, the influence of elemental nanosized boron (nB) addition (up to 1.5 wt.%) on rheological properties of irregular shape 316L SS powders is also evaluated using capillary rheometer method. It is observed that rheological parameters for solid powder loading of powder gas atomized (PGA) and bimodal powder P25/75 316L SS underwent sudden change from PGA-69 vol.% to PGA-72 vol.% and P25/75-67 vol.% to P25/75 316L SS 70 vol.%, respectively. Thus it is concluded that PGA-69 vol.% and P25/75-67 vol.% are optimal powder solid loadings corresponding to the lowest values of activation energies. [ABSTRACT FROM AUTHOR]

P(3HB-co-4HB) copolymer was modified using collagen by adapting dual solvent system. The surface properties of samples were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), organic elemental analysis (CHN analysis), and water contact angle measurements. The effects of collagen concentration, scaffold thickness, and 4HB molar fraction on the hydrophilicity were optimized by the Taguchi method. The orthogonal array experiment was conducted to obtain the response for a hydrophilic scaffold. Analysis of variance (ANOVA) was used to determine the significant parameters and determine the optimal level for each parameter. The results also showed that the hydrophilicity of P(3HB-co-4HB)/collagen blend scaffolds increased as the collagen concentration increased up to 15 wt% with a molar fraction of 50 mol% at 0.1 mm scaffold thickness. The biocompatibility of the P(3HB-co-4HB)/collagen blend surface was evaluated by fibroblast cell (L929) culture. The collagen blend scaffold surfaces showed significant cell adhesion and growth as compared to P(3HB-co-4HB) copolymer scaffolds. [ABSTRACT FROM AUTHOR]

The design of a microstrip reflectarray formed by 81 variable size double elliptical rings illuminated by a conical feed is presented.Because of double resonance, the double elliptical rings provide an increased phasing range of unit cells that exceeds the required minimum of 360°. Printed on a single substrate and supported by a layer of foam and a conducting ground, they also offer a slow phase slope as a function of their size, and thus provide an increased operational bandwidth and a good manufacturing error tolerance. The performance of the designed reflectarray is investigated via full-wave electromagnetic simulations and measurements on the manufactured prototype. The presented results show a wideband performance of the designed reflectarray. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:1083-1087, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25912 [ABSTRACT FROM AUTHOR]

This study dealt with the use of various quantities of modified red mud as a nanofiller in a poly(hydroxy ether) of bisphenol A (Phe) based matrix. Phe-based polymer nanocomposites reinforced with acidically and organically modified layered red mud were prepared by a conventional solvent-casting technique. The best dispersion occurred in the polymer nanocomposites where the interactions between the functional groups of the polymer matrix and those of the organic substitution of the red mud appeared to be the highest. The particle size of the modified red mud was determined by field emission scanning electron microscopy. The as-synthesized composite films were typically characterized by Fourier transform infrared spectroscopy and X-ray diffraction. The dispersion of the modified fillers within the matrix was studied by transmission electron microscopy. The thermal properties measured by thermogravimetric analysis showed enhanced thermal stability of a series of composite materials. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The finite element method is coupled with the topology gradient (TG) and level-set (LS) methods for optimizing the shape of microwave components using a computer-aided design model. On the one hand, the LS approach is based on the classical shape derivative; while on the other hand, the TG method is precisely designed for introducing new perturbations in the optimization domain. These two approaches, which consist in minimizing a cost function related to the component behavior, are first described. Regarding given electrical specifications, these techniques are applied to optimize the distribution of ceramic parts of a dual-mode resonator in order to improve its behavior. The optimized dielectric resonators result in a wide spurious-free stop band. A comparison between classical and optimized dual mode resonator is presented. Theoretical results are then validated by careful measurements. © 2009 Wiley Periodicals, Inc. Int J RF and Microwave CAE 2010. [ABSTRACT FROM AUTHOR]

Perineal hernia repair using a bone fixation anchoring system for the mesh - a video vignette I Dear Sir i , The extralevator abdominoperineal excision (ELAPE) has been introduced to overcome the high rates of bowel perforation and positive circumferential resection margins associated with traditional abdominoperineal resection. Perineal hernia repair using a bone fixation anchoring system for the mesh. [Extracted from the article]

We have identified a common novel mutation (Q354X) in the argininosuccinate lyase ( ASL) gene in Saudi patients with argininosuccinic aciduria (ASAuria; McKusick 207900). The two index patients were siblings, had a neonatal onset of the disease and were diagnosed based on the clinical presentation and confirmed by analysis of their dried blood spots (DBS) by tandem mass spectrometry (MS/MS). The ASL gene was then analysed by direct sequencing. A further 28 patients with a confirmed diagnosis of ASAuria based on MS/MS of their DBS were tested by sequencing for the presence of the Q354X mutation. This mutation was found in 14 out of the 28 patients (50%) tested. Our work indicates that the Q354X allele is common, may account for 50% of the abnormal ASL genes in the Saudi population, and is likely to be associated with the neonatal form of the disease. We recommend that all patients diagnosed with ASAuria in Saudi Arabia or of Arab origin be tested for this mutation and for Q116X, which has been described previously. In addition, further analysis is needed to identify other underlying disease mutations for ASAuria in the Saudi population. [ABSTRACT FROM AUTHOR]

HLA-DO is an intracellular nonclassical MHC class II molecule expressed in the endocytic pathway of B lymphocytes. It shapes the repertoire of peptides bound to classical class II molecules such as HLA-DR by regulating the activity of HLA-DM. Using a peptide corresponding to the cytoplasmic tail of HLA-DOβ, we have developed a mouse monoclonal antibody, HKC5. Immunofluorescence microscopy revealed that HKC5 recognizes HLA-DO molecules present in the endoplasmic reticulum as well as those in vesicular compartments of the endocytic pathway. In addition, the antibody detects the isolated β chain on Western blots. Using mutants of the DOβ cytoplasmic tail fused to a reporter molecule and expressed in epithelial cells, we showed by flow cytometry that the antibody epitope includes one or both of the leucine residues forming the lysosomal sorting signal. Finally, we have used HKC5 to evaluate the presence of the HLA-DOβ chain in HeLa cells expressing the class II transactivator protein CIITA. Our flow cytometry and confocal microscopy analyses showed a marked expression of DOβ suggesting that HLA-DO could accumulate under the influence of CIITA in non-B cells. [ABSTRACT FROM AUTHOR]

Highlights This study investigates the development of a novel biocomposite tailored for sustainable packaging applications, integrating cellulosic woven fiber mats into poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV), a biocompatible polymer. Utilizing hot press compression molding, composite boards with a thickness of 3 mm were fabricated. The cellulosic fiber mats were chemically modified with propionic anhydride, enhancing their compatibility with the PHBV matrix. Varied concentrations of reinforced propionylated cellulosic fiber mats (10%, 20%, 30%, 40%, and 50%) were investigated. The propionylated cellulosic abaca fiber composites exhibited superior functional properties, thermal stability, biodegradability, and mechanical performance compared to pure PHBV matrix. Notably, mechanical properties showed significant improvement with increased cellulosic fiber content, particularly achieving optimal strength at 30 wt% reinforcement. Chemical treatment enhanced interfacial bonding, evident in higher water contact angles and confirmed by Field Emission Scanning Electron Microscopy (FE‐SEM) analysis. The biodegradation rate of biocomposites was faster compared to the control PHBV biopolymer. Despite potential agglomeration issues at higher concentrations, PHBV/chemically modified cellulosic fiber composites hold promise as sustainable packaging materials, contributing to a greener future in packaging applications. Successful preparation of PHBV composites with treated plant fibers. Propionic anhydride treatment enhances fiber‐PHBV bonding and water resistance. Improved strength at 30 wt% treated abaca fiber in PHBV composites. Propionylated fibers enhance biodegradability compared to pure PHBV matrix. Promising sustainable packaging with chemically modified cellulosic fibers. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented on surgical approaches to the tongue base of patients advised to undergo radiofrequency treatment for snoring.

The global shift towards biodegradable composite has made polysaccharides a green alternative to synthetic polymers owing to their biocompatibility, sustainability, and ecofriendly biomaterials. Despite the limitations in their applications, many studies have validated the effectiveness of using organic or inorganic fillers to ameliorate their mechanical and barrier properties. However, the understanding of how polysaccharides matrix is enhanced by fillers is still inexplicit. Hence, it is imperative to review the effects of using inorganic and organic fillers in some prominent polysaccharides in terms of mechanical and water barrier properties while taking into account the function of filler morphology, size and loading. Although it is intricate to indicate the best filler used for each of the polysaccharides matrices, this review served as a "food for thought" on the established works of enhanced‐matrix filler combinations aimed at improving the mechanical and barrier properties of biodegradable films based on neutral or negatively charged polysaccharides‐based composite films for potential application in food packaging, agriculture, biomedicine and constructions sector. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47251. [ABSTRACT FROM AUTHOR]