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The bone fracture cases have been increasing yearly, accompanied by the increased number of patients experiencing non-union or delayed union after their bone fracture. Although clinical materials facilitate fracture healing (e.g., metallic and composite materials), they cannot fulfill the requirements due to the slow degradation rate, limited osteogenic activity, inadequate osseointegration ability, and suboptimal mechanical properties. Since early 2000, nanomaterials successfully mimic the nanoscale features of bones and offer unique properties, receiving extensive attention. This paper reviews the achievements of nanomaterials in treating bone fracture (e.g., the intrinsic properties of nanomaterials, nanomaterials for bone defect filling, and nanoscale drug delivery systems in treating fracture delayed union). Furthermore, we discuss the perspectives on the challenges and future directions of developing nanomaterials to accelerate fracture healing.

The rapid development of digital finance has effectively reduced financial challenges in rural regions and created new prospects for agricultural production. This article examines the impact of digital financial development on rice production in Sichuan Province using the 2011–2021 Peking University Digital Financial Inclusion Index and data from 20 prefecture-level cities, as well as a fixed effects model. The mechanism of action is also discussed. The findings reveal that the advancement of digital finance plays an important role in boosting the expansion of rice production, and that digital finance influences rice output by increasing farmers’ willingness to participate in insurance and increasing the availability of credit. A heterogeneity analysis reveals that digital finance has a substantial effect on mountainous and economically poor areas. As a result, this article suggests that the breadth and depth of usage of rural digital finance, as well as the development of rural digital financial services in underdeveloped areas, should be expanded.

Abstract Amyloid‐β (Aβ) and Tau proteins are the main components of Aβ plaques and neurofibrillary tangles in Alzheimer's disease (AD), and their abnormal aggregation is closely related to the pathogenesis of AD. The production of reactive oxygen species (ROS) and the aggregation of Aβ and Tau form a vicious circle, which leads to the aggravation of AD. However, inhibiting the aggregation of Aβ and Tau or scavenging ROS is not able to effectively reverse the progression of AD. Herein, we prepared a H2O2 responsive multifunctional nanocomposite UCNPs@mSiO2‐MB@AuNPs (abbreviated as USMA) to inhibit the aggregation of Aβ and Tau. In this system, USMA could respond to H2O2 to detach gold nanoparticles (AuNPs) and lead to the release of methylene blue (MB) from mesoporous silica (mSiO2), where AuNPs and MB can inhibit Aβ and Tau aggregation, respectively. Furthermore, USMA could consume H2O2 by reacting with them. Meanwhile, upconversion luminescence of UCNPs can be used to track USMA and monitor MB release, which could provide information on the content of MB in the lesion area. Importantly, the USMA can effectively reduce the cytotoxicity induced by Aβ and Tau aggregation. This work opens up a possibility to improve therapeutic efficacy for the treatment of AD.

Air-assisted boom sprayer is proven to be one of the best pesticide application methods to achieve uniform deposition of droplets in the canopy and improve the effective utilization of pesticides. However, the air flow velocity, air flow volume and air flow direction of the orchard sprayer should match the characteristic parameters of the target canopy, equipment spraying parameters and meteorological conditions so as to improve the spraying quality and reduce environmental pollution. This paper elaborates on the research status of air-assisted field sprayers and orchard sprayers, summarizes the research methods of air-assisted sprayers in four aspects, including experimental verification, theoretical analysis, simulation and structural optimization, and clarifies the advantages and disadvantages of these methods. It also presents two future research and development trends, including the intelligent, precise dynamic regulation of air flow velocity, air flow volume and air flow direction and the instant feedback of spraying quality, hoping to provide a reference for the research of air-assisted spray technology and equipment.

Organic color-centers (OCCs) in single-walled carbon nanotubes (SWCNTs) have been intensively investigated for quantum technologies, bio- and chemical sensing, bioimaging. The precise localization of OCCs at a scalable manner will bring about a revolution into next generation optoelectronics, which, however, remains a great challenge till now. Here, a scalable, low cost and universal photo-patterning strategy is developed to implant OCCs at desired locations on (6,5)-chirality SWCNT films by combining optically active diazonium chemistry and micro-contact printing methods. Notably, the patterns can be tunable by changing the solvents used for the patterning chemistry, affording control over the weight of diazonium salts at different regions. A systematic investigation reveals that the solvent properties (polarity and vapor pressure), the volume and concentration of ink used, the patterning methods, and the concentration of MeODz all contribute to the tunable patterning. This spatial accurate and solvent tunable photo-patterning technique is simple, scalable, and amenable to the integration of other color center chemistries and 2D transition metal dichalcogenides for the next-generation chip-integrated nanoelectronics and optoelectronics with high device uniformity and manipulability at molecular level.

An orchard variable-rate sprayer applies the appropriate amount of plant protection products only where they are needed based on detection data from advanced sensors, a system that has attracted increasing attention. The latest developments in the detection unit, variable control unit, and signal-processing algorithm of the variable-rate sprayer are discussed. The detection of target position and volume is realized with an ultrasonic sensor, a laser scanning sensor, or other methods. The technology of real-time acquisition of foliage density, plant diseases and pests and their severity, as well as meteorological parameters needs further improvements. Among the three variable-flow-rate control units, pulse width modulation was the most widely used, followed by pressure-based, and variable concentration, which is preliminarily verified in the laboratory. The variable air supply control unit is tested both in the laboratory and in field experiments. The tree-row-volume model, the leaf-wall-area model, and the continuous application mode are widely used algorithms. Advanced research on a variable-rate sprayer is analyzed and future prospects are pointed out. A laser-based variable-rate intelligent sprayer equipped with pulse width modulation solenoid valves to tune spray outputs in real time based on target structures may have the potential to be successfully adopted by growers on a large scale in the foreseeable future. It will be a future research direction to develop an intelligent multi-sensor-fusion variable-rate sprayer based on target crop characteristics, plant diseases and pests and their severity, as well as meteorological conditions while achieving multi-variable control.

In this study, we report the synthesis and characterisation of a thermogelling poly(carbonate urethane) system comprising poly(ethylene glycol) (PEG), poly(propylene glycol) (PPG) and poly(polytetrahydrofuran carbonate) (PTHF carbonate). The incorporation of PTHF carbonate allowed for the control of the lower critical solution temperature (LCST) and decreased critical gelation concentration (CGC) of the thermogels significantly. In addition, the as-prepared thermogels displayed low toxicity against HepG2, L02 and HEK293T cells. Drug release studies were carried out using doxorubicin (Dox). Studies conducted using nude mice models with hepatocellular carcinoma revealed that the Dox-loaded poly(PEG/PPG/PTHF carbonate urethane) thermogels showed excellent in vivo anti-tumour performance and effectively inhibited tumour growth in the tested model.

Pluronic F127 exhibits thermogelling behaviour at 20–30 °C via a micelle packing mechanism. Disruption of the micelle packing increases the sol-gel temperature, but results in the decrease of modulus. Herein, we reported a method to modify F127 with polyhedral oligosilsesquioxane (POSS) to impart a higher gelling temperature without yielding the property and strength of the thermogel. The thermal degradation temperature was enhanced to 15 °C after POSS incorporation and the gelling temperature shifted 10 °C higher, without sacrificing the modulus of the gel. Rheological studies supported the claim that the gel property was reinforced after POSS incorporation. F127-POSS copolymer matrix stored more energy from POSS reinforcement, which saw larger Lissajous curve areas before the collapse of the microstructure for the same amount of stress applied. These results indicated that modification with POSS would raise the sol-gel transition temperature without sacrificing the modulus of the gel.

The synthesis and gene transfection efficiency of a series of amphiphilic copolymers, poly(2-(dimethylamino)ethyl methacrylate)-poly (methacrylate isobutyl polyhedral oligomeric silsesquioxane) (PDMAEMA-POSS) copolymers are reported. The hydrophobic POSS interior allows a cell-sensitizing drug such as paclitaxel to be incorporated, whereas the cationic and hydrophilic PDMAEMA corona allows the complexation of anionic DNA to form a nano-sized polyplex. These drug-encapsulated copolymers display excellent gene transfection efficiency compared with polyethylenimine or PDMAEMA homopolymers. [ABSTRACT FROM AUTHOR]

Protein transport is an important phenomenon in biological systems. Proteins are transported via several mechanisms to reach their destined compartment of cell for its complete function. One such mechanism is the microtubule mediated protein transport. Up to now, there are no reports on synthetic systems mimicking the biological protein transport mechanism. Here we report a highly efficient method of mimicking the microtubule mediated protein transport using newly designed biotinylated peptides encompassing a microtubule-associated sequence (MTAS) and a nuclear localization signaling (NLS) sequence, and their final conjugation with streptavidin-coated CdSe/ZnS quantum dots (QDs). Our results demonstrate that these novel bio-conjugated QDs enhance the endosomal escape and promote targeted delivery into the nucleus of human mesenchymal stem cells via microtubules. Mimicking the cellular transport mechanism in stem cells is highly desirable for diagnostics, targeting and therapeutic applications, opening up new avenues in the area of drug delivery. [ABSTRACT FROM AUTHOR]

Recently, lanthanide based nanocrystals with upconversion fluorescence emission have attracted a lot of interest and the nanocrystals have been used for bioimaging, biodetection, and therapeutic applications. Use of the nanocrystals for multiplexed detection has also been explored; however, nanocrystals with multicolor emission are required. Some efforts have been made to tune the emission spectra of the nanocrystals based on manipulation of upconverting lanthanide ions doped in the crystals or creation of core/shell structures. In this work, alkali ions with an ionic radius slightly larger or smaller than Na such as Li and K were doped into NaYF4:Yb,Er nanocrystals and their effect on the crystal structure and subsequently the upconversion emission spectra were studied. It was found that the phase transition occurs in the nanocrystals when a different amount of Li and K was doped. Furthermore, the intensity ratios between the blue, green, and red emission peaks changed accordingly, and make it possible to tune the upconversion fluorescence of the nanocrystals by Li and K doping. [ABSTRACT FROM AUTHOR]

A (110) oriented Tb0.3Dy0.7Fe1. 95 alloy rod was annealed at 500 °C under a magnetic field of 0.3 T, which was applied 35° away from the rod axis. X-ray diffraction characterization and optical microscopy observation showed that both the crystal orientation and morphologies were retained after magnetic annealing. Magnetic force microscopy images exhibited obvious change of the magnetic domain configurations. The magnetostrictive performance was changed drastically. Saturation axial magnetostriction λ||s increased from 1023 to 1650 ppm by the ratio of 61.3%, but saturation perpendicular magnetostriction λ⊥s decreased from --802 to --624 ppm. Maximum magnetostrictive strain coefficients d33 and d31 were found to be enhanced by 29.3% and 32.6%, respectively. In addition, the fields for obtaining both optimum d33 and d31 decreased, which indicates that better magnetostrictive performance can be achieved at lower external fields after magnetic annealing. [ABSTRACT FROM AUTHOR]