As a natural polysaccharide, chitosan possesses good biocompatibility, biodegradability and biosafety. Its hydroxyl and amino groups make it an ideal carrier material in the construction of ...polymer-drug conjugates. In recent years, various synthetic strategies have been used to couple chitosan with active substances to obtain conjugates with diverse structures and unique functions. In particular, chitosan conjugates with antimicrobial activity have shown great application prospects in the fields of medicine, food, and agriculture in recent years. Hence, we will place substantial emphasis on the synthetic approaches for preparing chitosan conjugates and their antimicrobial applications, which are not well summarized. Meanwhile, the challenges, limitations, and prospects of antimicrobial chitosan conjugates are described and discussed.
Highly conductive multi-walled nanotubes (MWCNT)/waterborne polyurethane (WPU) composites were prepared using facile latex technology without surfactant, in which the solid composites were achieved ...by filtration process to prevent the re-aggregation of MWCNT during drying process. MWCNT was distributed along the interfaces of polyurethane particles, constructing segregated structure without insulating surfactant. Therefore, high conductivity of 362.6 ± 23.1 S m−1 was obtained at CNT content of 10.6 wt%, resulting in excellent electromagnetic interference (EMI) shielding effectiveness (SE) of 24.7 dB at thin film thickness of 0.4 mm in X-bands. Considering lightweight and thin thickness, outstanding specific shielding effectiveness (SSE) of 537 dB cm2 g−1 was achieved, higher than most values of CNT composites ever reported. Furthermore, the composites exhibited desirable mechanical properties with high elongation at break of 62%, demonstrating promising applications for commercial EMI shielding, especially for flexible and stretchable devices.
Stretchable and conductive materials can have important application in many areas, such as wearable electronics and healthcare devices. Conducting polymers have very limited elasticity because of ...their rigid conjugated backbone. In this work, highly stretchable and conductive polymer films are prepared by coating or casting aqueous solution of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) and a soft polymer, including poly(ethylene glycol), poly(ethylene oxide), or poly(vinyl alcohol). The soft polymers can greatly improve the stretchability and the conductivity of PEDOT:PSS. The elongation at break can be increased from 2% up to 55%. The soft polymers can also enhance the conductivity of PEDOT:PSS from 0.2 up to 75 S cm–1. The conductivity is further enhanced by adding dimethyl sulfoxide (DMSO) or ethylene glycol (EG) into the aqueous solutions of the polymer blends. Polymer blends with an elongation at break of close to 50% and a conductivity of 172 S cm–1 are attained.
A systematic study of the in-medium correction factor (F) on nucleon-nucleon elastic cross section is performed within the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model. The effects of ...the beam energy dependence of F on the directed, elliptic flow and nuclear stopping in 197Au+197Au collisions with energy ranging from 0.09 to 0.8A GeV are explored. It is found that the directed, elliptic flow and nuclear stopping at relatively low energies are very sensitive to F, and the sensitivity gradually weakens with increasing beam energy. The beam energy dependent in-medium correction factor F is deduced from the comparison of the excitation functions of the directed, elliptic flow and nuclear stopping between the calculated results and the FOPI experimental data.
Recently, with the emergence of new light sources, polarization devices, and detectors, together with a prominent increase in data processing capability, polarization techniques find more and more ...applications in various areas, one of which is biomedicine. For probing the characteristic features of complex biomedical specimen, Mueller matrix polarimetry has demonstrated distinctive advantages. Mueller matrix polarimetry can be achieved on other optical techniques by adding the polarization state generator and analyzer to their existing optical paths appropriately. Common biomedical optical equipment, such as microscopes and endoscopes, can be upgraded to fulfill Mueller matrix imaging and measurement abilities. Compared with traditional non-polarization optical methods, Mueller matrix polarimetry can provide far more information to characterize the samples, including the anisotropic optical properties, such as birefringence and diattenuation, as well as the distinctive features of various scattering particles and microstructures. Also, Mueller matrix polarimetry is more sensitive to scattering by sub-wavelength microstructures. As a label-free and non-invasive tool, Mueller matrix polarimetry has broad application prospects in biomedical studies and clinical diagnosis. In this review, we provide an introduction to the Mueller matrix methodology, including the Stokes-Mueller formalism, and also the decomposition and transformation methods to derive new parameters. We also summarize the status of the Mueller matrix polarimetric field, including recent improvements, both in instrumentation and data analysis. The current and future applications of Mueller matrix polarimetry in biomedicine are provided and discussed.
Younger generations actively use social media to access health information. However, research shows that they also avoid obtaining health information online at times when confronted with uncertainty.
...This study aims to examine the phenomenon of health information avoidance among Generation Z, a representative cohort of active web users in this era.
Drawing on the planned risk information avoidance model, we adopted a qualitative approach to explore the factors related to information avoidance within the context of health and risk communication. The researchers recruited 38 participants aged 16 to 25 years for the focus group discussion sessions.
In this study, we sought to perform a deductive qualitative analysis of the focus group interview content with open, focused, and theoretical coding. Our findings support several key components of the planned risk information avoidance model while highlighting the underlying influence of cognition on emotions. Specifically, socioculturally, group identity and social norms among peers lead some to avoid health information. Cognitively, mixed levels of risk perception, conflicting values, information overload, and low credibility of information sources elicited their information avoidance behaviors. Affectively, negative emotions such as anxiety, frustration, and the desire to stay positive contributed to avoidance.
This study has implications for understanding young users' information avoidance behaviors in both academia and practice.
Abstract
In order to solve the problem of “attaching importance to the construction while neglecting the evaluation” in construction of continuous rigid frame bridges in China, a post-construction ...evaluation system was established by taking the elasticity modulus of concrete, frictional loss of prestress and loss of prestress as the indexes, and a three-level fuzzy comprehensive post-design evaluation model was built. The continuous rigid frame bridge on the Chongqing-Hechuan segment of Lanzhou-Haikou Expressway was taken as an example to conduct a comprehensive post-design evaluation. The results showed that the studied bridge was evaluated and categorized into Category II in the bridge design evaluation system, indicating a good design and operation state of this bridge. Suggestions and countermeasures were proposed for the design of continuous rigid frame bridges, with a vision to provide a basis for construction of bridges of the same type.
The DEAD-box helicase family member DDX3X (DBX, DDX3) functions in nearly all stages of RNA metabolism and participates in the progression of many diseases, including virus infection, inflammation, ...intellectual disabilities and cancer. Over two decades, many studies have gradually unveiled the role of DDX3X in tumorigenesis and tumour progression. In fact, DDX3X possesses numerous functions in cancer biology and is closely related to many well-known molecules. In this review, we describe the function of DDX3X in RNA metabolism, cellular stress response, innate immune response, metabolic stress response in pancreatic β cells and embryo development. Then, we focused on the role of DDX3X in cancer biology and systematically demonstrated its functions in various aspects of tumorigenesis and development. To provide a more intuitive understanding of the role of DDX3X in cancer, we summarized its functions and specific mechanisms in various types of cancer and presented its involvement in cancer-related signalling pathways.
Hierarchical porous carbon with high areal energy density in supercapacitor has attracted extensive attention with increasing demand for compact and portable devices. Lignin based porous carbon ...monolith was fabricated via dual templates (P123 and silica nanoparticles) and carbonization procedure, where hierarchical porous structure with tuneable mesopore sizes and distributions could be modulated via incorporation of silica nanoparticles with size of 200 nm, 100 nm, and 7 nm, respectively. Due to higher surface area and optimized porous structure which facilitate fast ion diffusion, carbon monolith fabricated from silica nanoparticle of 7 nm exhibited superior electrochemical performance, which reached a high areal capacitance of 2.7 F cm−2 and excellent volumetric capacitance of 104.5 F cm−3 with mass loading of 13.6 mg cm−2 in 6 M KOH aqueous solution. Moreover, the symmetric cell assembled with this carbon electrode gave rise to a large amount of energy (131 μWh cm−2) at high power densities (1368 μW cm−2) and excellent cycle stability of 92.9% after 10 000 cycles, facilitating implementation of lignin-derived materials in commercial energy storage products.
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•Lignin derived hierarchical porous carbon monolith was fabricated by dual templates.•The porous structure can be tuned by the size and amount of silica nanoparticles.•High capacitance performance can be realized by optimizing porous structure.•2.7 F cm−2, 104.5 F cm−3, and 200.2 F g−1 were achieved at 0.1 A g−1.
Efficient defect classification is one of the most important preconditions to achieve online quality inspection for hot-rolled strip steels. It is extremely challenging owing to various defect ...appearances, large intraclass variation, ambiguous interclass distance, and unstable gray values. In this paper, a generalized completed local binary patterns (GCLBP) framework is proposed. Two variants of improved completed local binary patterns (ICLBP) and improved completed noise-invariant local-structure patterns (ICNLP) under the GCLBP framework are developed for steel surface defect classification. Different from conventional local binary patterns variants, descriptive information hidden in nonuniform patterns is innovatively excavated for the better defect representation. This paper focuses on the following aspects. First, a lightweight searching algorithm is established for exploiting the dominant nonuniform patterns (DNUPs). Second, a hybrid pattern code mapping mechanism is proposed to encode all the uniform patterns and DNUPs. Third, feature extraction is carried out under the GCLBP framework. Finally, histogram matching is efficiently accomplished by simple nearest-neighbor classifier. The classification accuracy and time efficiency are verified on a widely recognized texture database (Outex) and a real-world steel surface defect database Northeastern University (NEU). The experimental results promise that the proposed method can be widely applied in online automatic optical inspection instruments for hot-rolled strip steel.
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