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In recent years, nanoparticles (NPs) derived from the self-assembly of natural polysaccharides have shown great potential in the biomedical field. Here, we described several self-assembly modes of natural polysaccharides in detail, summarized the natural polysaccharides mostly used for self-assembly, and provided insights into the current applications and achievements of these self-assembled NPs. As one of the most widespread substances in nature, most natural polysaccharides exhibit advantages of biodegradability, low immunogenicity, low toxicity, and degradable properties. Therefore, they have been fully explored, and the application of chitosan, hyaluronic acid, alginate, starch, and their derivatives has been extensively studied, especially in the fields of biomedical. Polysaccharides based NPs were proved to improve the solubility of insoluble drugs, enhance tissue target ability and realize the controlled and sustained release of drugs. When modified by hydrophobic groups, the amphiphilic polysaccharides can self-assemble into NPs. Other driven forces of self-assembly include electrostatic interaction and hydrogen bonds. Up to the present, polysaccharides-based nanoparticles have been widely applied for tumor treatment, antibacterial application, gene therapy, photodynamic therapy and transporting insulin. • Electrostatic force, hydrophobic force, and hydrogen bonding drive self-assembly of NPs. • Self-assembly is environmental-friendly, biocompatible, convenient, and low toxic. • Polysaccharides-based NPs improve pharmacokinetics and achieve targeted drugs delivery. • NPs used for accurate drug release, combination therapy and gene therapy are drawing attention. [ABSTRACT FROM AUTHOR]

[Display omitted] • AFP played a positive role in maintain the quality of frozen chicken. • Pretreatment with AFP reduced drip loss in chicken upon cryopreservation. • 0.20% AFP retarded protein of chicken during freezing. • 0.25% AFP slowed the damage of chicken myofibrils caused by large ice crystals. The cryo-protective effects of different concentrations of antifreeze protein (AFP, 0 %, 0.10 %, 0.15 %, 0.20 %, 0.25 %, w/v) on chicken frozen at −18 °C for different storage perispeeods were investigated by monitoring water holding capacity (WHC), water distribution, color, protein properties, microstructure and histological changes. The results showed that AFP significantly maintained the quality traits of frozen chicken. Treatment with 0.20 % AFP represented highest cryo-protective effect on the WHC and protein properties during frozen storage. The carbonyl content with 0.20 % AFP was significantly lower than that of without AFP (P < 0.05). Besides, the myofibrils of chicken supplemented with AFP, especially with 0.25 % AFP, had significantly tighter microstructure, smaller ice crystal area and equivalent diameter than those of without AFP treatment (P < 0.05) after 75 d freezing storage. Overall, AFP had a positive effect to improve the quality of frozen chicken, and it was a potential, safe and efficient cryo-protective agent. [ABSTRACT FROM AUTHOR]

• Effect of the closed end on the smoke movement in tunnel are investigated. • Fire-closed end distance and heat release rates are varied. • Initial position of one-dimensional smoke spread stage from the closed end is given. • Correlation of the ceiling temperature distribution in tunnel is proposed. • The applicability of the correlation is verified by comparing with the previous results. Urban utility tunnels have relatively small cross-sections and isolated environment, which is different from the common transportation tunnels. Thus, the fire situation in the utility tunnel is more severe, and the spread of smoke has special characteristics due to the isolated environment. Considering the detection, early warning, and prevention of utility tunnel fire, it is essential to understand the characteristics of smoke movement and temperature variation during the occurrence of fires in the restricted environments of utility tunnels. This study employs numerical simulations to investigate the influence of closed end on the smoke transport and temperature variation of the ceiling in utility tunnel. The range of the heat release rate is 3 to 15 MW, and the longitudinal distance (d) between the closed end and the fire source varies from 3 to 30 m. The results indicate that due to the presence of the closed end in utility tunnel fires, the side of fire source near the closed end is prone to accumulating more smoke and forming a thicker smoke layer. Moreover, the backflow of smoke after colliding with the closed end will cause disturbance to the stability of the smoke layer on the other side. As the fire source progressively travels away from the closed end, the disturbance caused by the accumulated smoke progressively weakens, and the concentrated smoke is more likely to reach a relatively stable state. Finally, a correlation is established, utilizing the starting location of the one-dimensional spread stage as a reference point, to anticipate ceiling smoke temperature variation over the longitudinal direction of the tunnel. To validate the applicability and reliability of the proposed correlation, a comparison is made with the data from previous studies on both closed-end and open-end tunnels. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of theaflavins (TFs), tea polyphenols (TP) and vitamin C (VC) on the nitrite residue amount, color, antioxidant capacity and N-nitrosamines inhibition in cured sausage. The addition of TFs, TP and VC combined with NaNO 2 respectively could significantly increase the a* value, nitroso pigment content and DPPH free radical scavenging rate, and effectively reduced the content of residual nitrite, metmyoglobin (MetMb) and total N-nitrosamines in cured sausages than treated only with NaNO 2 (P < 0.05), of which TFs group was the most significant (P < 0.05). It was indicated that the addition of TFs, TP could better inhibit the oxidation of cured sausages. UV–vis spectroscopy also showed pentacoordinate nitrosyl ferrohemochrome was the main pigment component in the samples. The results demonstrated that TFs and TP could contribute to the desired color and safety of sausage. • Theaflavins (TFs) and tea polyphenols (TP) inhibit the formation of N-nitrosamines. • TFs and TP could significantly reduce the residual nitrite in cured sausage. • TFs and TP could inhibit the oxidation of myoglobin to improve the color of • Sausage. • TFs and TP are promising materials for reducing the residue nitrite and MetMb. [ABSTRACT FROM AUTHOR]

• The effect of fire source height and various air entrainment conditions on the ceiling jet characteristic was studied. • The variances in flame extension behavior in transverse and longitudinal directions under the ceiling were investigated. • The temperature distribution in various directions inside the tunnel was analyzed. • A correlation of the flame length of the ceiling jet was quantified and analyzed with the effective heat release rate. • The correlations are verified by comparing them with the previous research results. This paper presents an experimental investigation into the impact of varying the location of the fire source within a tunnel on the temperature and morphology of the ceiling jet in different directions. It proposes a method to predict the longitudinal and transverse flame length based on previous studies about flame morphology. The experiment is conducted on a reduced scale (1/8th) tunnel, with the fire source being a porous gas burner utilizing propane as fuel. It comprised two series of transverse fire source locations (against the wall or at the centerline of the tunnel). Each series included five heights, ranging from 0 m to 0.4 m, and 12 heat release rates, spanning from 5.67 kW to 85.10 kW. The results of the experiments demonstrated that elevating the fire source or positioning it against the wall facilitated the formation of ceiling jets. The limited transverse space of the tunnel leads to greater constraints on the transverse ceiling jets, resulting in a longer longitudinal ceiling jet than a transverse ceiling jet. And the longer longitudinal ceiling jets simultaneously result in a higher longitudinal temperature distribution under the ceiling. This study proposed the effective HRR Q ef based on the assumption of a constant heat release rate per unit flame volume to analyze the flame length. And the dimensionless flame length L f / D has been found to scale with the dimensionless effective HRR Q ef ⁎ by the power of 2/5. This correlation is further validated by comparing it with the previous experimental data. [ABSTRACT FROM AUTHOR]

Abstract x Nb 2 O 5 –7.5La 2 O 3 -Al 2 O 3 ceramic composites with in-situ-grown columnar Al 2 O 3 crystals were successfully prepared by microwave sintering at 1450–1525 °C using α-Al 2 O 3 , Nb 2 O 5 , and La 2 O 3 powders as raw materials. X-ray diffraction results indicated that the main phases were Al 2 O 3 , LaNbO 4 , and Nb 2 O 5 in the prepared samples. A field emission scanning electron microscope (FESEM) showed that the Al 2 O 3 crystals appeared as columnar in the structure. Moreover, the grain size of the columnar Al 2 O 3 crystals increased with the Nb 2 O 5 content. The ratio of the major axis to the minor axis of the crystals was largest when the Nb 2 O 5 content was 15 vol%. Furthermore, the grain-growth kinetics index (n), growth activation energy (Q), and growth mechanism of the columnar Al 2 O 3 crystals were studied. The results indicated that the Nb 2 O 5 addition could promote formation and growth of columnar Al 2 O 3 crystals, and the grain-growth activation energy indicated that the dissolution process controls the crystal growth. The growth mechanism of the columnar Al 2 O 3 crystals was also studied. The present work demonstrated that Nb 2 O 5 is a good additive for the preparation of Nb 2 O 5 –7.5La 2 O 3 -Al 2 O 3 composite ceramics with columnar Al 2 O 3 crystals. [ABSTRACT FROM AUTHOR]

The 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) ceramic and zirconia matrix ceramics doped with 7.5% (volume percent) nano-Al 2 O 3 (7.5Al 2 O 3 –92.5ZrO 2 ) were fabricated by two-step microwave sintering (MS-II), and two-step conventional sintering (CS-II) and one step microwave sintering (MS-I) as control group. The results show that the machinable index of two groups of samples varied considerably. The optimum first step sintering temperature of 7.5Al 2 O 3 –92.5ZrO 2 composite ceramics and 3Y-TZP ceramics were 950 °C and 900 °C, respectively. The properties of 7.5Al 2 O 3 –92.5ZrO 2 composite ceramics prepared by two-step microwave sintering were superior to that of two-step conventional sintering and one-step microwave sintering. The relative density of 7.5Al 2 O 3 –92.5ZrO 2 composite ceramics reached 99.35% by two-step microwave sintering. Its hardness, fracture toughness and bending strength were 13.09 GPa, 11.62 MPa m 1/2 and 766.89 MPa, respectively. Adding nano-Al 2 O 3 could improve microstructure of the ceramics and have an effect of dispersion strengthening, which enhanced the properties of the materials. Compared with the 3Y-TZP ceramics, the properties of ZrO 2 composites with alumina addition were greatly improved, the fracture toughness and the bending strength were improved 20.3% and 33.9%, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • An extensive review for the design and optimization of vaginal meshes. • Effects of properties and manufacturing process on clinical efficacy were studied. • Application and challenges of synthetic and natural polymers were reviewed. Pelvic floor dysfunction (PFD) is a common gynecological problem that affects millions of women. Current treatment strategies are to restore the normal anatomical structure by non-operative procedures (such as pelvic floor myoelectric stimulation) or surgery (such as vaginal mesh implantation). Although vaginal meshes can provide effective, long-term and minimally invasive treatment for patients, certain life-altering complications may occur. Physical characteristics (such as porosity, mesh weight and mechanical properties), manufacturing process and material type are parameters that can greatly influence cell attachment, tissue proliferation and regeneration. The best clinical effectiveness of surgical meshes could be obtained by optimizing these parameters. Material type has a particularly important influence on the mechanical strength, biodegradation rate and biocompatibility of the implants. Therefore, material type selection is crucial for the development of an ideal pelvic floor repair mesh for use in pelvic floor reconstruction. The materials that are suitable for use in vaginal meshes have been broadly classified into three groups, which are synthetic polymers, natural polymers and polymer blends. This review mainly focuses on the application and biological characteristics of synthetic polymers, natural polymers and polymer blends in pelvic floor tissue engineering. [ABSTRACT FROM AUTHOR]

Double-layer indicator film (DIF, the indicator layer made of carrageenan (CAR), curcumin (CUR) and/or anthocyanin (ATH), and the emulsified layer (named KC layer) made of konjac glucomannan (KGM) and camellia oil.) was fabricated to monitor the chicken meat freshness in this study. The three kinds of DIFs (CAR-ATH-KC, CAR-ATH-CUR-KC and CAR-CUR-KC) were tested. The results of FTIR demonstrated that different components were bound together by hydrogen bond. The double-layer structure films were clearly observed by SEM images. The presence of KC layer significantly improved the thermal stability, water- and UV-resistance performance, and mechanical properties of the indicator layer. Furthermore, Visual observation indicated that the CAR-ATH-KC and CAR-ATH-CUR-KC labels used to monitor the chicken meat freshness at 25 °C presented the more obvious color change than the CAR-CUR-KC label. [Display omitted] • The double-layer indicator films (DIFs) were fabricated by twice individual casting. • Anthocyanin and curcumin were used as pH-sensitive solution in film-forming matrix. • The emulsified layer improved the water- and UV-resistance performance of DIF. • The color of CAR-ATH-KC and CAR-CUR-ATH-KC film clearly changed during meat storage. [ABSTRACT FROM AUTHOR]

The porous 2D metal-organic frameworks (MOFs) possess 1D channels derived from the stacking sequence of the 2D layers. The nanoparticles (NPs)@2D MOFs core-shell structures are potential composites catalysts in exposing more accessible active sites via 1D channels, in addition to enriching the reactants in the porous structure as normal MOFs. Here we present a novel and universal strategy for embedding pre-synthesized metal NPs into the 2D MOFs, forming a fully encapsulated compact core-shell structure. The method has proven to be versatile not only for embedding NPs with different metals and morphologies but also for 2D MOFs with different nodes and linkers. Various characterization methods, including powder X-ray diffraction, transmission electron microscopy, Raman spectroscopy, etc. have been used to elaborate the mechanism of this encapsulation process, through which an attractive and promising 'clean' interface can be obtained. [Display omitted] • Novel encapsulation of pre-synthesized metal nanoparticles into 2D MOFs. • A "clean" interface was obtained when the ionic surfactants capping on nanoparticles peeled off after encapsulation. • An archetype for well-controlled NPs-2D MOF interface with unblocked channels. [ABSTRACT FROM AUTHOR]

Schematic diagram illustrating the fabrication process of LBL-structured mats. [Display omitted] • Both Chitosan (CS) and Collagen (COL) are naturally abundant and biocompatible. • PCL/N6 mats coated with oppositely charged CS spontaneously and alternately. • The LBL-mats could mimic the structure and function of pelvic floor. • The mats possess better bacterial inhibition with the increased CS layers. Developing novel, lightweight and biocompatible mesh for pelvic organ prolapse, a gynecological disease, has attracted the global interest of biomedical researchers. In our study, polycaprolactone and nylon 6 mats with excellent mechanical properties were fabricated via co-electrospinning. Positively charged chitosan with antimicrobial properties and negatively charged collagen with good biocompatibility were then assembled on the nanofiber mats via layer by layer (LBL) technology. SEM and mechanical property tests showed that LBL deposition increased the nanofibers' diameter and elastic modulus. To evaluate the successful deposition process, the zeta potential, The Fourier-transform infrared, X-ray diffraction, and X-ray photoelectron spectroscopy analyses were conducted to systematically study the mats' chemical characterization. The results indicated that the mats' composition and structure significantly changed after LBL modification. Cell biology experiments demonstrated that the LBL-structured mats can facilitate cell growth, proliferation, and adhesion. Antibacterial tests confirmed their excellent antibacterial activity. Chitosan/Collagen-coated Polycaprolactone/Nylon 6 mats demonstrate considerable potential as implant materials for pelvic reestablishment in pelvic organ prolapse patients. [ABSTRACT FROM AUTHOR]