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Porous polyethylene glycol terephthalate (PET) film is a kind of mesopore structure template with pore size ranging from nanometer to micrometer by chemical etching after irradiation of heavy ions. The etching rate is an important factor affecting the pore morphology and quality of the membrane. In this paper, four stacked PET film were irradiated with 140 MeV 32S ions at room temperature and vacuum. During chemical etching of irradiated samples, the path etching rate Vt was determined by conduction method, and the bulk etching rate Vb was determined by weighing method. The relationship between etching temperature, concentration, sensitization time, and etching rate was studied. The results show that the etching rate is exponentially correlated with the etching temperature, and increases linearly with the increase of the etching solution concentration. When the concentration of NaOH is 3 mol·L−1 and the etching temperature is 75°C, the formation of cylindrical micropores is the most favorable. The pore size of porous PET film can be adjusted, and the relationship between pore size and etching time is dnm=15nm+0.24t. This is of great significance for the preparation of nanowires with uniform size and stable properties. Highlights: We have obtained the optimal conditions for obtaining cylindrical holes.The relationship between the diameter of holes and etching time were determined. [ABSTRACT FROM AUTHOR]

The astaxanthin nanocapsules (ASX-LNC) was prepared by high-pressure homogenization technology, the microstructure, stability, antioxidant activity, and in vitro release characteristics of ASX-LNC were characterized and evaluated. The ASX-LNC comprised a core material and wall materials. The core material was composed of astaxanthin oil, and the wall materials were composed of β-cyclodextrin, decapolyglycerol monooleate, soybean lecithin (PC60), glycerol, and deionized water. The mean particle size of the ASX-LNC was 206.9 ± 2.8 nm, and the polydispersity index (PdI) value was 0.218 ± 0.026. The zeta potential of ASX-LNC was −26.16 ± 0.87 mV. The loading amount of ASX-LNC was 0.546%±0.032%, and the encapsulation efficiency was 99.65%±0.13%, indicating that the preparation process was feasible. The stability of ASX-LNC was determined under different conditions, indicating good stability of the ASX-LNC. In antioxidant research, the inhibition rate of free radicals of ASX-LNC was 91.03 ± 0.87% under 250 μg/mL for 30 min, and the inhibition rate of free radicals of astaxanthin ethanol solution was 90.83 ± 1.37%. The antioxidant capacity of astaxanthin was not affected by the encapsulation, which demonstrated the effect of prolonging the release of active ingredients due to the protection of the biological activity of astaxanthin by encapsulation. Compared with the astaxanthin ethanol solution, the ASX-LNC had a slow-release effect and could prolong the action time of active substances. Overall, ASX-LNC is a potential carrier for application in food and health products, which can control the release of active substances. [ABSTRACT FROM AUTHOR]

A facile template method was employed to synthesize Fe nanowires of different sizes, dimensions. Comprehensive analyses were conducted to explore their morphology, structure, composition, and magnetic properties. The surface of as-prepared Fe nanowires was modified with SiO2 by sol–gel method to improve the dispersion of as-prepared Fe nanowires in aqueous solution. Furthermore, the relaxation properties, biocompatibility and in vivo imaging abilities of the Fe@SiO2 nanowires were evaluated. The study revealed that the SiO2-coated Fe nanowires functioned effectively as transverse relaxation time (T2) contrast agents (CAs). Notably, as the length of the Fe@SiO2 nanowires increased, their diameter decreased, leading to a higher the transverse relaxivity (r2) value. Our study identified that among the Fe nanowires synthesized, the Fe3@SiO2 nanowires, characterized by a diameter of around 30 nm and a length of approximately 500 nm, exhibited the highest r2 value of 59.3 mM−1 s−1. These nanowires demonstrated good biocompatibility and non-toxicity. Notably, upon conducting small animal imaging a 1.5 T with Sprague–Dawley rats, we observed a discernible negative enhancement effect in the liver. These findings indicate the promising potential of Fe@SiO2 nanowires as T2 CAs, with the possibility of tuning their size for optimized results. [ABSTRACT FROM AUTHOR]

The Yellow River Basin is an important energy base and economic belt in China, but its water resources are scarce, its ecology is fragile, and the task of achieving the goal of carbon peak and carbon neutrality is arduous. Carbon compensation potential can also be used to study the path to achieving carbon neutrality, which can clarify the potential of one region's carbon sink surplus to be compensated to the other areas. Still, there needs to be more research on the carbon compensation potential of the Yellow River Basin. Therefore, this study calculated the carbon compensation potential using the β convergence test and parameter comparison method. With the help of spatial measurement tools such as GIS, GeoDa, Stata, and social network analysis methods, the spatiotemporal pattern and network structure of the carbon compensation potential in the Yellow River Basin were studied from the perspective of urban agglomeration. The results demonstrate the following: (1) The overall carbon compensation rate of the YRB showed a downward trend from 2005 to 2019, falling by 0.94, and the specific pattern was "high in the northwest and low in the southeast". The spatial distribution is roughly spread along the east–west axis, and the distribution axis and the center of gravity keep shifting to the northwest. It also showed a weak divergence and a bifurcation trend. (2) The carbon compensation rate in the YRB passed the spatial correlation and β convergence tests, demonstrating the existence of spatial correlation and a "catch-up effect" among cities. (3) The overall distribution pattern of the carbon compensation potential in the YRB is a "low in the west and high in the east" pattern, and its value increased by 8.86% during the sampled period. (4) The network correlation of carbon compensation potential in the YRB has been significantly enhanced, with the downstream region being more connected than the upstream region. (5) The Shandong Peninsula Urban Agglomeration has the largest network center, followed by the Central Plains Urban Agglomeration, and the Ningxia along the Yellow River Urban Agglomeration has the fewest linked conduction paths. According to the research results, accurate and efficient planning and development suggestions are proposed for urban agglomeration in the Yellow River Basin. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the astaxanthin-loaded nanostructured lipid carriers (ASX-NLC) prepared using a high-pressure homogenization transport system for local application of astaxanthin. Dynamic light scattering (DLS) and X-ray diffraction (XRD) were used to study the effect of microencapsulation on the properties of ASX-NLC. The mean size of ASX-NLC was about 108.43 ± 0.26 nm and PdI was 0.176 ± 0.002. The ASX-NLC had high encapsulation efficiency which was 95.69 ± 0.13%. Good light stability and temperature stability were shown at the ASX-NLC, indicating that the preparation process was feasible. The 2,2-diphenyl-1-pyridylohydrazinyl (DPPH) scavenging test showed that ASX-NLC could still play an antioxidant role. In vitro release studies showed that compared with an astaxanthin ethanol solution, an ASX-NLC could maintain astaxanthin release more effectively. In vitro permeation studies showed that ASX-NLC could increase astaxanthin retention in the skin. In conclusion, ASX-NLC could significantly enhance astaxanthin accumulation during dermal applications. The research results have important reference significance for local skin applications and provide a basis for the development of nanostructured lipid carriers. ASX-NLC might be suitable carriers for the local application of astaxanthin. Graphical Abstract [ABSTRACT FROM AUTHOR]

Summary: The research assesses the properties of the phloretin‐loaded nanostructured lipid carriers (NLC) hydrogel bead. Scanning electron microscopy (SEM), dynamic light scattering (DLS) and X‐ray diffraction (XRD) were used to investigate the properties of phloretin NLC hydrogel beads. The in vitro release study indicated that the phloretin NLC hydrogel beads continued to release within 24 h. The simulated digestibility studies showed that the phloretin NLC hydrogel beads could improve digestive behaviour by controlling lipid intake. The results showed that hydrogel beads could be used as an appropriate delivery system for the encapsulation of phloretin. Hence, the NLC hydrogel beads are a potential carrier of phloretin for application in healthy food, which can control lipid intake. [ABSTRACT FROM AUTHOR]

Our objective was to investigate if the internal aqueous phase gelation of Water‐in‐oil‐in‐water double emulsions encapsulated in alginate beads would affect their structural stability and lipid hydrolysis during in vitro digestion. Therefore, bioactive molecules such as (−)‐epigallocatechin gallate were encapsulated into different types of delivery systems: original double emulsions (as control) and incorporated double emulsions (filled in alginate hydrogel beads), both with non‐gelled or gelled internal aqueous phase by locust bean gum and κ‐carrageenan. After 2 h of gastric digestion, the gelled original emulsions showed smaller mean droplet diameters and less coalescence during the in vitro simulated gastrointestinal digestion compared to the non‐gelled original emulsions. For the incorporated emulsions, oil droplets released from beads aggregated under intestinal conditions, and the rate of lipolysis was delayed. Interestingly, the internal aqueous phase gelation also impacted the rate and cumulative amount of free fatty acids (FFA) released. Practical Application: The combination of incorporating (−)‐epigallocatechin gallate‐loaded double emulsions into the alginate hydrogel matrix and gelling the internal aqueous phase was a benefit to regulating the rate and extent of lipid digestion for specific applications in foods, such as to control blood lipid levels and appetite. [ABSTRACT FROM AUTHOR]

Jujube production is threatened by jujube witches' broom (JWB) disease, which is caused by JWB phytoplasma. The jujube TCP transcription factor (TF) ZjTCP16 may be involved in the interaction of jujube plants with JWB phytoplasma. In this study, qRT-PCR proved that the expression pattern of ZjTCP16 was altered by JWB phytoplasma. The gene functions of ZjTCP16 were analyzed by its overexpression in Arabidopsis and jujube, as well as knock-down in. The overexpression of ZjTCP16 in Arabidopsis and jujube resulted in dwarfism and small leaves, while the zjtcp16 CRISPR mutants were higher than the WT. Microscopic observation of paraffin sections of jujube stems showed that ZjTCP16 affected the size of cells. The interactions of ZjTCP16 with ZjAS2 and ZjLOB in both the cytoplasm and nucleus were demonstrated by yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays. Yeast one-hybrid (Y1H) assays and qRT-PCR further confirmed that ZjTCP16 affected the expression of genes involved in leaf morphogenesis and cell proliferation (ZjAS1, ZjKNAT1, ZjKNAT2 and ZjKNAT6) at the mRNA level through the ZjAS2 and ZjLOB pathways. In conclusion, ZjTCP16 regulates plant growth and cell size by altering the expression pattern of morphogenesis-related genes in jujube. [ABSTRACT FROM AUTHOR]

To overcome the negative contrast limitations, and to improve the sensitivity of the magnetic resonance signals, the mesoporous silica coated Fe/Mn multilayered nanowires (NWs) were used as a T1–T2 dual‐mode contrast agents (CAs). The single component Fe and Mn NWs, and Fe/Mn multilayer NWs were synthesized by electrodeposition in the homemade anodic aluminum oxide (AAO) templates with the aperture of about 30 nm. The structural characterization and morphology of single component and multisegmented NWs was done by X‐ray diffraction and transmission electron microscopy. The elemental composition of Fe/Mn multilayerd NWs was confirmed by energy‐dispersive X‐ray and energy‐dispersive spectrometer. Vibrating sample magnetometer was used to test the magnetic properties, and 1.5 T magnetic resonance imaging (MRI) scanner was used to measure the relaxation efficiency. Importantly, the MRI study indicated that the Fe/Mn multilayer NWs showed a significant T1–T2 imaging effect, and have longitudinal relaxivity (r1) value, that is, 1.25 ± 0.0329 × 10−4 μM−1 s−1 and transverse relaxivity (r2), that is, 5.13 ± 0.123 × 10−4 μM−1 s−1, which was two times of r1 value (0.654 ± 0.00899 × 10−4 μM−1 s−1) of Mn NWs, and r2 value (2.96 ± 0.0415 × 10−4 μM−1 s−1) of Fe NWs. Hence, Fe/Mn multilayer NWs have potential to be used as T1–T2 dual‐mode CAs. [ABSTRACT FROM AUTHOR]

Magnetic nanostructures and nanomaterials play essential roles in modern bio medicine and technology. Proper surface functionalization of nanoparticles (NPs) allows the selective bonding thus application of magnetic forces to a vast range of cellular structures and biomolecules. However, the spherical geometry of NPs poises a series of limitations in various potential applications. Mostly, typical spherical core shell structure consists of magnetic and non-magnetic layers have little tunability in terms of magnetic responses, and their single surface functionality also limits chemical activity and selectivity. In comparison to spherical NPs, nanowires (NWs) possess more degrees of freedom in achieving magnetic and surface chemical tenability. In addition to adjustment of magnetic anisotropy and inter-layer interactions, another important feature of NWs is their ability to combine different components along their length, which can result in diverse bio-magnetic applications. Magnetic NWs have become the candidate material for biomedical applications owing to their high magnetization, cheapness and cost effective synthesis. With large magnetic moment, anisotropy, biocompatibility and low toxicity, magnetic NWs have been recently used in living cell manipulation, magnetic cell separation and magnetic hyperthermia. In this review, the basic concepts of magnetic characteristics of nanoscale objects and the influences of aspect ratio, composition and diameter on magnetic properties of NWs are addressed. Some underpinning physical principles of magnetic hyperthermia (MH), magnetic resonance imaging (MRI) and magnetic separation (MS) have been discussed. Finally, recent studies on magnetic NWs for the applications in MH, MRI and MS were discussed in detail. [ABSTRACT FROM AUTHOR]

Core–shell Fe@Fe3O4 nanowires (NWs) were successfully prepared on a homemade anodic aluminum oxide (AAO) template by the anodic oxidation of Fe NWs followed by annealing reduction. A field-emission scanning electron microscope was used to observe the morphology of the AAO template, which shows that the diameter of AAO template was 30 nm. TEM results confirm a thin oxide layer was formed on Fe NWs, confirming the core–shell nature of Fe NWs. The TEM analysis shows that with the increase in anodizing time, the oxide layer thickness was increased from 2.4, 4.6, 5.9 nm, respectively. The elemental composition of core–shell Fe NWs was confirmed by energy-dispersive X-ray spectrometer. The oxide phase of Fe could not be easily distinguished by X-ray analysis, because of the line width broadening of nanocrystals; thus, the valence states of Fe in Fe@Fe2O3 and Fe@Fe3O4 NWs were further analyzed by X-ray photoelectron spectroscopy (XPS). XPS results confirm the oxide nature of Fe2O3 and Fe3O4 in core–shell Fe NWs. The influence of oxide layer thickness on the magnetic properties of core–shell Fe@Fe3O4 NWs was investigated by vibrating sample magnetometry. Magnetic measurement revealed that the coercivity and squareness values of core–shell Fe@Fe3O4 NWs gradually increased with the increase in the Fe3O4 shell thickness. Results clearly showed that the size and magnetism of the core–shell Fe@Fe3O4 NWs can be adjusted to a certain extent by this synthetic method, so as to meet different requirements in desired biomedical applications. [ABSTRACT FROM AUTHOR]

In this paper, exponential stability of periodic solution for an inertial neural network is studied. Different from most research on inertial neural networks, the model in this paper is based on memristors and is involved with periodic solutions. In order to simplify the difficulty in dealing with inertial terms and constructing Lyapunov functions, the inertial neural network in this paper is transformed into a suitable neural network with enhanced characteristics by using appropriate variable transformation method. Under the Lyapunov stability theory and Leary-Schauder alternative theorem, we prove the existence and global exponential stability of the periodic solution for the inertial neural network under mild conditions. At last, the feasibility of the theoretical conclusions is illustrated by some numerical examples. [ABSTRACT FROM AUTHOR]

We proposed a compact and simple polarization phase-shifting lateral shearing interferometer using two polarization beam splitter plates (PBSP). This interferometer is composed of two PBSP, a quarter-wave plate, an analyzer and a CCD camera. With the two PBSP positioned in appropriate spatial positions, optical path difference compensation is achieved, which allows for the implement of aplanatic and common-path shearing interferometer. Therefore, the system possesses significant advantages of simple structure, compact and strong anti-interference ability. The effectiveness of the interferometer is demonstrated by simulations and experiments. [ABSTRACT FROM AUTHOR]

A lot of nanomaterials are using T1-T2 dual mode magnetic resonance (MR) contrast agents (CAs), but multilayer nanowire (NW) with iron (Fe) and manganese (Mn) as T1-T2 dual modal CAs has not been reported yet. Herein, we synthesized a Fe/Mn multilayer NW with an adjustable Fe layer, as T1-T2 dual-mode CAs. The relaxation performance of Fe/Mn multilayer NW was studied at 1.5 T. Results show that, when the length of the Fe layer is about 10 nm and the Mn is about 5 nm, the r1 value (21.8 mM−1s−1) and r2 value (74.8 mM−1s−1) of the Fe/Mn multilayer NW are higher than that of Mn NW (3.7 mM−1s−1) and Fe NW (59.3 mM−1s−1), respectively. We predict that our Fe/Mn multilayer NW could be used as T1-T2 dual mode MRI CAs in the near future. [ABSTRACT FROM AUTHOR]

In the last couple of decades, there has been a lot of progress in the synthesis methods of nano-structural materials, but still the field has a large number of puzzles to solve. Metal nanowires (NWs) and their alloys represent a sub category of the 1-D nano-materials and there is a large effort to study the microstructural, physical and chemical properties to use them for further industrial applications. Due to technical limitations of single component NWs, the hetero-structured materials gained attention recently. Among them, multi-segmented NWs are more diverse in applications, consisting of two or more segments that can perform multiple function at a time, which confer their unique properties. Recent advancement in characterization techniques has opened up new opportunities for understanding the physical properties of multi-segmented structures of 1-D nanomaterials. Since the multi-segmented NWs needs a reliable response from an external filed, numerous studies have been done on the synthesis of multi-segmented NWs to precisely control the physical properties of multi-segmented NWs. This paper highlights the electrochemical synthesis and physical properties of multi-segmented NWs, with a focus on the mechanical and magnetic properties by explaining the shape, microstructure, and composition of NWs. [ABSTRACT FROM AUTHOR]

Phytoplasmas are plant pathogenic bacteria that inhabit the phloem sieve elements in infected plants and lack a cell wall. Infection of the woody perennial Ziziphus jujuba with phytoplasma causes jujube witches' broom (JWB), a disease that causes heavy crop losses. The TEOSINTE BRANCHED 1/CYCLOIDEA/PCF (TCP) transcription factors (TFs) are plant-specific regulators of plant morphogenesis, development, and defense after phytoplasma infection. While the TCP gene family has been studied in many plants, there is no report on TCPs in jujube. In this study, 21 ZjTCP TFs were identified and bioinformatically analyzed based on the genome of the Dongzao cultivar. Another 2 ZjTCPs were found in the genome of the Junzao cultivar. Physicochemical properties of the ZjTCP proteins were quite varied, indicating possible versatility of functions. ZjTCP proteins ranged from 172 to 590 amino acids (aa), had isoelectric points (pIs) between 5.53 (ZjTCP1) and 9.81 (ZjTCP11), and molecular weights ranging from 19,279.98 (ZjTCP11) to 61,784.17 kDa (ZjTCP19). Interaction network mapping predicted several hubs, such as ZjTCP6, ZjTCP7, ZjTCP8, ZjTCP15, ZjTCP16, and ZjTCP19, among which ZjTCP6 and ZjTCP16 were predicted to function in plant defense and morphogenesis. Spatiotemporal expression analysis of the ZjTCPs showed that ten of the ZjTCP genes were detected after infection with 'Candidatus Phytoplasma ziziphi'. ZjTCP6, ZjTCP7, ZjTCP16, and ZjTCP19 were up-regulated after phytoplasma infection. ZjTCP16 showed the most significant increase in transcript levels, after the emergence of disease symptoms. ZjTCP12, ZjTCP15, and ZjTCP18 were down-regulated after phytoplasma infection. We concluded that ZjTCP6 and ZjTCP16 were most likely regulatory factors with roles during the plant response to jujube witches' broom. [ABSTRACT FROM AUTHOR]