A Universal Biomacromolecule-Enabled Assembly Strategy for Constructing Multifunctional Aerogels with 90% Inorganic Mass Loading from Inert Nano-Building Blocks.

Inert inorganic nano-building blocks, such as carbon nanotubes (CNTs) and boron nitride (BN) nanosheets, possess excellent physicochemical properties. However, it remains challenging to build aerogels with these inert nanomaterials unless they are chemically modified or compounded with petrochemical polymers, which affects their intrinsic properties and is usually not environmentally friendly. Here, a universal biomacromolecule-enabled assembly strategy is proposed to construct aerogels with 90 wt% ultrahigh inorganic loading. The super-high inorganic content is beneficial for exploiting the inherent properties of inert nanomaterials in multifunctional applications. Taking chitosan-CNTs aerogel as a proof-of-concept demonstration, it delivers sensitive pressure response as a pressure sensor, an ultrahigh sunlight absorption (94.5%) raising temperature under light (from 25 to 71 °C within 1 min) for clean-up of crude oil spills, and superior electromagnetic interference shielding performance of up to 68.9 dB. This strategy paves the way for the multifunctional application of inert nanomaterials by constructing aerogels with ultrahigh inorganic loading.

Programmable Electrical Signals Induce Anisotropic Assembly of Multilayer Chitosan Hydrogels.

Multilayer hydrogels are widely used in biomedical-related fields due to their complex and variable spatial structures. Various strategies have been developed for preparing multilayer hydrogels, among which electrically induced self-assembly provides a simple and effective method for multilayer hydrogel fabrication. By application of an oscillatory electrical signal sequence, multilayer hydrogels with distinct boundaries can be formed according to the provided programmable signals. In this work, we establish an electrical field in microfluidics combined with polarized light microscopy for in situ visualization of anisotropic construction of multilayer chitosan hydrogel. The noninvasive, real-time birefringence images allow us to monitor the orientation within the hydrogel in response to electrical signals. An increased birefringence was observed from the solution-gel side to the electrode surface side, and a brief electrical signal interruption did not affect the anisotropic assembly process. This understanding of the oscillatory electrical signal-induced hydrogel anisotropy assembly allows us to fabricate chitosan hydrogels with a complex and spatially varying structure.

Selective cleavage of C ß -O-4 bond for lignin depolymerization via paired-electrolysis in an undivided cell.

The cleavage of C-O bonds is one of the most promising strategies for lignin-to-chemicals conversion, which has attracted considerable attention in recent years. However, current catalytic system capable of selectively breaking C-O bonds in lignin often requires a precious metal catalyst and/or harsh conditions such as high-pressure H2 and elevated temperatures. Herein, we report a novel protocol of paired electrolysis to effectively cleave the Cß-O-4 bond of lignin model compounds and real lignin at room temperature and ambient pressure. For the first time, "cathodic hydrogenolysis of Cß-O-4 linkage" and "anodic C-H/N-H cross-coupling reaction" are paired in an undivided cell, thus the cleavage of C-O bonds and the synthesis of valuable triarylamine derivatives could be simultaneously achieved in an energy-effective manner. This protocol features mild reaction conditions, high atom economy, remarkable yield with excellent chemoselectivity, and feasibility for large-scale synthesis. Mechanistic studies indicate that indirect H* (chemical absorbed hydrogen) reduction instead of direct electron transfer might be the pathway for the cathodic hydrogenolysis of Cß-O-4 linkage.

Janus Fibrous Mats Based Suspended Type Evaporator for Salt Resistant Solar Desalination and Salt Recovery.

Solar desalination has been recognized as an emerging strategy for solving the pressing global freshwater crisis. However, salt crystallization at the photothermal interface frequently causes evaporator failure. In addition, arbitrary discharge of concentrated brine produced during desalination results in potential ecological impacts as well as wastage of valuable minerals. In the present work, a suspended-type evaporator (STEs) constructed using Janus fibrous mats is reported. The fibrous structure wicks brine to the evaporation layer and the salt gets confined in the evaporation layer until crystallization for zero liquid discharge due to the suspended design. Enhanced evaporation is observed because STEs have an additional low-resistance vapor escape path directly from the evaporation layer to the atmosphere compared to traditional floating Janus evaporators. Moreover, owing to the drastically different wettability on both sides, the evaporator allows salt crystallization only on the hydrophilic bottom layer, thus eliminating salt accumulation at the hydrophobic photothermal interface. With this unique structural design, the proposed evaporator not only maintains a high evaporation rate of 1.94 kg m-2 h-1 , but also demonstrates zero liquid discharged salt resistance and ideal recovery of the mineral in brine.

Electrical Writing to Three-Dimensional Pattern Dynamic Polysaccharide Hydrogel for Programmable Shape Deformation.

The ability to pattern and actuate hydrogels is essential for biomimetics, soft robotics, and biosensors. Here an electrical writing technique with the capability to create both surface and across thickness patterns in dynamic chitosan-H+ /agarose hydrogel by electronically generated pH gradient is introduced. The diffusible pH cues deprotonate and re-assemble chitosan chains by hydrogen bonds, changing the electrical writing domains from original loose structure to a dense layer and resulting in different mechanical stress and swell ability that causes the hydrogel to deform. The deformable trend can be modulated by writing depth and selective writing area on the surface, and significantly enhanced by temperature increment. Finally, a dual electrical writing process to create three-dimensional patterns and demonstrate programmable shape transition by differing patterns is performed.

Assessment of urban sustainability efficiency based on general data envelopment analysis: a case study of two cities in western and eastern China.

Sustainable urban development focuses on enhancing urban well-being, while also balancing the demands of urban social and economic development, natural resource consumption, and environmental pollution. This work used general data envelopment analysis to assess the urban sustainability efficiency (USE) and sustainability potential (SP) in Lanzhou and Xiamen, two cities that are characteristic of urban areas in western and eastern China. The assessment indicator system included important natural and urban welfare factors as input and output indices, respectively. The results showed that overall urban sustainability efficiency increased in Lanzhou and Xiamen from 1985 to 2010, but that the sustainability of natural resources clearly decreased. The urban sustainability efficiency of Xiamen was higher than that of Lanzhou, and the sustainability potential of Xiamen was lower than that of Lanzhou; this indicates that Xiamen performed better in terms of urban sustainable development. The urban sustainability efficiency in Xiamen has increased with increasing urban population, and the rate and scale of economic development have been higher than in Lanzhou. The assessment and analysis performed in this study show that cities with different natural resources and development characteristics have different forms, patterns, and trajectories of sustainable development.

A dynamic and self-crosslinked polysaccharide hydrogel with autonomous self-healing ability.

Natural polymeric hydrogels with self-healing capability that can recover the functionalities and structures of gels after damage are extremely attractive due to their emerging applications in the biomedical field. Here we report a self-healable polymeric hydrogel by self-crosslinking two natural polymers acrylamide-modified chitin (AMC) containing amino groups and oxidized alginate containing dialdehyde groups. The generation of the self-crosslinked hydrogel relies on the dynamic covalent linkage through Schiff base between the polysaccharide chains. The self-healing capability of the crosslinked hydrogel depends on the molar ratio of AMC and oxidized alginate and the surrounding pH. Under certain circumstances, the damaged hydrogel shows a complete recovery and can be stretched to a favorable extent, which is seldom observed for polysaccharide self-healing hydrogel. Notably, we find that the self-healing ability can be "stored" by freeze-drying and "activated" by rehydration. In addition, we demonstrate that the hydrogel can be used as a soft template to guide the repair of inorganic materials like hydroxyapatite. We anticipate that this self-healable hydrogel consisting of biocompatible and biodegradable polysaccharides can be applied to various biomedical fields.

Trade-off between water pollution prevention, agriculture profit, and farmer practice--an optimization methodology for discussion on land-use adjustment in China.

Agricultural decision-making to control nonpoint source (NPS) water pollution may not be efficiently implemented, if there is no appropriate cost-benefit analysis on agricultural management practices. This paper presents an interval-fuzzy linear programming (IFLP) model to deal with the trade-off between agricultural revenue, NPS pollution control, and alternative practices through land adjustment for Wuchuan catchment, a typical agricultural area in Jiulong River watershed, Fujian Province of China. From the results, the lower combination of practice 1, practice 2, practice 3, and practice 7 with the land area of 12.6, 5.2, 145.2, and 85.3 hm(2), respectively, could reduce NPS pollution load by 10%. The combination yields an income of 98,580 Chinese Yuan/a. If the pollution reduction is 15%, the higher combination need practice 1, practice 2, practice 3, practice 5, and practice 7 with the land area of 54.4, 23.6, 18.0, 6.3, and 85.3 hm(2), respectively. The income of this combination is 915,170 Chinese Yuan/a. The sensitivity analysis of IFLP indicates that the cost-effective practices are ranked as follows: practice 7 > practice 2 > practice 1 > practice 5 > practice 3 > practice 6 > practice 4. In addition, the uncertainties in the agriculture NPS pollution control system could be effectively quantified by the IFLP model. Furthermore, to accomplish a reasonable and applicable project of land-use adjustment, decision-makers could also integrate above solutions with their own experience and other information.

Cytotoxicity of calcium rectorite micro/nanoparticles before and after organic modification.

Organically modified rectorite (OREC) micro/nanoparticles can be synthesized by organic modification from calcium rectorite (Ca(2+)-REC or REC), a common form of rectorite in nature. Although REC and OREC have potential applications in food packing and drug delivery, their cytotoxicity is not clear. In the present study, we investigated and compared the cytotoxicity of REC and OREC micro/nanoparticles in Chang liver cells, the human normal hepatic cells, and human hepatoma HepG2 cells. The interlayer spacing of OREC was enlarged after organic modification. After treatment with REC or OREC for 24 h at 1 and 5 µg/mL, they were taken up by Chang liver cells. REC and OREC induced cytotoxicity in Chang liver and HepG2 cells at almost all doses (1, 2.5, 5, 7.5, and 10 µg/mL) after 6, 24, and 48 h of treatment (P < 0.05 or P < 0.01). Compared with REC, OREC was more cytotoxic. However, there was no difference in the cytotoxicity of REC and OREC between the two cell lines. After treatment with REC or OREC at 7.5 and 10 µg/mL for 24 h, the apoptotic and necrotic percentages of Chang liver cells were increased (P < 0.05 or P < 0.01). The levels of apoptosis-related proteins Bax, Bcl-2, and pro-caspase-3 were all decreased in Chang liver cells after 24 h of exposure to REC or OREC at 5, 7.5, 10 µg/mL. There was no change in the relative ratio of Bax/Bcl-2 after treatment, indicating that REC or OREC-induced apoptosis was not associated with Bax-related mitochondria-mediated apoptotic pathway. Our results suggested that OREC was more cytotoxic than REC, but the underlying mechanisms need further investigation.

Coding for hydrogel organization through signal guided self-assembly.

Complex structured soft matter may have important applications in the field of tissue engineering and biomedicine. However, the discovery of facile methods to exquisitely manipulate the structure of soft matter remains a challenge. In this report, a multilayer hydrogel is fabricated from the stimuli-responsive aminopolysaccharide chitosan by using spatially localized and temporally controlled sequences of electrical signals. By programming the imposed cathodic input signals, chitosan hydrogels with varying layer number and thickness can be fabricated. The inputs of electrical signals induce the formation of hydrogel layers while short interruptions create interfaces between each layer. The thickness of each layer is controlled by the charge transfer (Q = ∫idt) during the individual deposition step and the number of multilayers is controlled by the number of interruptions. Scanning electron micrographs (SEMs) reveal organized fibrous structures within each layer that are demarcated by compact orthogonal interlayer structures. This work demonstrates for the first time that an imposed sequence of electrical inputs can trigger the self-assembly of multilayered hydrogels and thus suggests the broader potential for creating an electrical "code" to generate complex structures in soft matter.

Functional nanoparticles in targeting glioma diagnosis and therapies.

Successful therapy and diagnosis of glioma is one of the biggest challenges in the biomedical fields. The incidence is growing gradually around the world. Annually, there are approximately 13,000 cases of glioblastoma multiforme diagnosed with historical 1-year and 5-year survival rates of 29.3% and 3.3%, respectively. The prognosis of patients with malignant glioma remains dismal. Due to its highly proliferative, infiltrative, and invasive property, development of effective preventative strategies to control the gliomas is in high demand. Meanwhile, the efficiency of drug delivery to glioma remains low owing to the non-specific, non-targeted nature of anti-tumor agents. Furthermore, the presence of the blood brain barrier and blood brain tumor barrier is another obstacle for gliomas treatments. Nanotechnology has brought a paradigm shift in the diagnosis and treatment of glioma. This review discusses the potential of various nanoparticles in the diagnosis of gliomas using some metal oxide, and in the therapy of gliomas including receptor-mediated, magnetic directing, and cell-mediated drug delivery systems. In this review, some physical techniques combined with nanoparticles (NPs) such as ultrasound therapy, thermochemotherapy, photodynamic therapy, and fluorescent magnetic NPs have also been summarized.

Utility of Immunohistochemistry in the Diagnosis of Pleuropulmonary and Mediastinal Cancers: A Review and Update.

CONTEXT.­: Immunohistochemistry has become a valuable ancillary tool for the accurate classification of pleuropulmonary and mediastinal neoplasms necessary for therapeutic decisions and predicting prognostic outcome. Diagnostic accuracy has significantly improved because of the continuous discoveries of tumor-associated biomarkers and the development of effective immunohistochemical panels. OBJECTIVE.­: To increase the accuracy of diagnosis and classify pleuropulmonary neoplasms through immunohistochemistry. DATA SOURCES.­: Literature review and the author's research data and personal practice experience. CONCLUSIONS.­: This review article highlights that appropriately selecting immunohistochemical panels enables pathologists to effectively diagnose most primary pleuropulmonary neoplasms and differentiate primary lung tumors from a variety of metastatic tumors to the lung. Knowing the utilities and pitfalls of each tumor-associated biomarker is essential to avoid potential diagnostic errors.

Janus silk fibroin/polycaprolactone-based scaffold with directionally aligned fibers and porous structure for bone regeneration.

To promote bone repair, it is desirable to develop three-dimensional multifunctional fiber scaffolds. The densely stacked and tightly arranged conventional two-dimensional electrospun fibers hinder cell penetration into the scaffold. Most of the existing three-dimensional structural materials are isotropic and monofunctional. In this research, a Janus nanofibrous scaffold based on silk fibroin/polycaprolactone (SF/PCL) was fabricated. SF-encapsulated SeNPs demonstrated stability and resistance to aggregation. The outside layer (SF/PCL/Se) of the Janus nanofiber scaffold displayed a structured arrangement of fibers, facilitating cell growth guidance and impeding cell invasion. The inside layer (SF/PCL/HA) featured a porous structure fostering cell adhesion. The Janus fiber scaffold containing SeNPs notably suppressed S. aureus and E. coli activities, correlating with SeNPs concentration. In vitro, findings indicated considerable enhancement in alkaline phosphatase (ALP) activity of MC3T3-E1 osteoblasts and upregulation of genes linked to osteogenic differentiation with exposure to the SF/PCL/HA/Se Janus nanofibrous scaffold. Moreover, in vivo, experiments demonstrated successful critical bone defect repair in mouse skulls using the SF/PCL/HA/Se Janus nanofiber scaffold. These findings highlight the potential of the SF/PCL-based Janus nanofibrous scaffold, integrating SeNPs and nHA, as a promising biomaterial in bone tissue engineering.

Dopamine-Modified Chitosan Patterning Hydrogel with Dynamic Information Storage Ability.

The storage of dynamic information in hydrogels has aroused considerable interest regarding the multiple responsiveness of soft matter. Herein, we propose an electrical writing methodology to prepare dopamine (DA)-modified chitosan hydrogels with a dynamic information storage ability. A pH-responsive chitosan hydrogel medium was patterned by cathodic writing to in situ generate OH- in the writing area, at which dopamine underwent an auto-oxidation reaction in the locally alkaline environment to generate a dark color. The patterned information on the hydrogel can be encoded simply by electrical signals. The speed of information retrieval is positively correlated with the charge transfer during the electrical writing process, and the hiding of information is negatively correlated with the environmental stimulus (i.e., dopamine concentration, pH value, etc.). To showcase the versatility of this medium for information storage and the precision of the pattern, a quick response (QR) code is electronically written on dopamine-modified chitosan hydrogel and can be recognized programmably by a standard mobile phone. The results show that electrical regulation is a novel means to program the information storage process of hydrogels, which inspires future research on structural and functional information storage using stimulus-responsive hydrogels.

Cellulose nanofibers embedded chitosan/tannin hydrogel with high antibacterial activity and hemostatic ability for drug-resistant bacterial infected wound healing.

Millions of patients annually suffer life-threatening illnesses caused by bacterial infections of skin wounds. However, the treatment of wounds infected with bacteria is a thorny issue in clinical medicine, especially with drug-resistant bacteria infections. Therefore, there is an increasing interest in developing wound dressings that can efficiently fight against drug-resistant bacterial infections and promote wound healing. In this work, an anti-drug-resistant bacterial chitosan/cellulose nanofiber/tannic acid (CS/CNF/TA) hydrogel with excellent wound management ability was developed by electrospinning and fiber breakage-recombination. The hydrogel exhibited an outstanding antibacterial property exceeding 99.9 %, even for drug-resistant bacteria. This hydrogel could adhere to the tissue surface due to its abundant catechol groups, which avoided the shedding of hydrogel during the movement. Besides, it exhibited extraordinary hemostatic ability during the bleeding phase of the wound and then regulated the wound microenvironment by absorbing water and moisturizing. Moreover, the CS/CNF/TA also promoted the regrowth of vessels and follicles, accelerating the healing of infected wound tissue, with a healing rate exceeding 95 % within a 14-day timeframe. Therefore, the CS/CNF/TA hydrogel opens a new approach for the healing of drug-resistant bacterial infected wounds.

Self-Adapting Biomass Hydrogel Embodied with miRNA Immunoregulation and Long-Term Bacterial Eradiation for Synergistic Chronic Wound Therapy.

Chronic wound rescue is critical for diabetic patients but is challenging to achieve with a specific and long-term strategy. The prolonged bacterial inflammation is particularly prevalent in hyperglycemia-induced wounds, usually leading to severe tissue damage. Such a trend could further suffer from an environmental suitability provided by macrophages for persisting Staphylococcus aureus (S. aureus) and even deteriorate by their mutual reinforcement. However, the strategy of both suppressing bacteria growth and immunoreprogramming the inflammatory type of macrophages to break their vicious harm to wound healing is still lacking. Here, a self-adapting biomass carboxymethyl chitosan (CMC) hydrogel comprising immunomodulatory nanoparticles is reported to achieve Gram-negative/Gram-positive bacteria elimination and anti-inflammatory cytokines induction to ameliorate the cutaneous microenvironment. Mechanistically, antibacterial peptides and CMCs synergistically result in a long-term inhibition against methicillin-resistant S. aureus (MRSA) over a period of 7 days, and miR-301a reprograms the M2 macrophage via the PTEN/PI3Kγ/mTOR signaling pathway, consequently mitigating inflammation and promoting angiogenesis for diabetic wound healing in rats. In this vein, immunoregulatory hydrogel is a promising all-biomass dressing ensuring biocompatibility, providing a perspective to regenerate cutaneous damaged tissue, and repairing chronic wounds on skin.

Activating Adsorption Sites of Waste Crayfish Shells via Chemical Decalcification for Efficient Capturing of Nanoplastics.

The property of being stubborn and degradation resistant makes nanoplastic (NP) pollution a long-standing remaining challenge. Here, we apply a designed top-down strategy to leverage the natural hierarchical structure of waste crayfish shells with exposed functional groups for efficient NP capture. The crayfish shell-based organic skeleton with improved flexibility, strength (14.37 to 60.13 MPa), and toughness (24.61 to 278.98 MJ m-3) was prepared by purposefully removing the inorganic components of crayfish shells through a simple two-step acid-alkali treatment. Due to the activated functional groups (e.g., -NH2, -CONH-, and -OH) and ordered architectures with macropores and nanofibers, this porous crayfish shell exhibited effective removal capability of NPs (72.92 mg g-1) by physical interception and hydrogen bond/electrostatic interactions. Moreover, the sustainability and stability of this porous crayfish shell were demonstrated by the maintained high-capture performance after five cycles. Finally, we provided a postprocessing approach that could convert both porous crayfish shell and NPs into a tough flat sheet. Thus, our feasible top-down engineering strategy combined with promising posttreatment is a powerful contender for a recycling approach with broad application scenarios and clear economic advantages for simultaneously addressing both waste biomass and NP pollutants.

Nanofiber-induced hierarchically-porous magnesium phosphate bone cements accelerate bone regeneration by inhibiting Notch signaling.

Magnesium phosphate bone cements (MPC) have been recognized as a viable alternative for bone defect repair due to their high mechanical strength and biodegradability. However, their poor porosity and permeability limit osteogenic cell ingrowth and vascularization, which is critical for bone regeneration. In the current study, we constructed a novel hierarchically-porous magnesium phosphate bone cement by incorporating extracellular matrix (ECM)-mimicking electrospun silk fibroin (SF) nanofibers. The SF-embedded MPC (SM) exhibited a heterogeneous and hierarchical structure, which effectively facilitated the rapid infiltration of oxygen and nutrients as well as cell ingrowth. Besides, the SF fibers improved the mechanical properties of MPC and neutralized the highly alkaline environment caused by excess magnesium oxide. Bone marrow stem cells (BMSCs) adhered excellently on SM, as illustrated by formation of more pseudopodia. CCK8 assay showed that SM promoted early proliferation of BMSCs. Our study also verified that SM increased the expression of OPN, RUNX2 and BMP2, suggesting enhanced osteogenic differentiation of BMSCs. We screened for osteogenesis-related pathways, including FAK signaing, Wnt signaling and Notch signaling, and found that SM aided in the process of bone regeneration by suppressing the Notch signaling pathway, proved by the downregulation of NICD1, Hes1 and Hey2. In addition, using a bone defect model of rat calvaria, the study revealed that SM exhibited enhanced osteogenesis, bone ingrowth and vascularization compared with MPC alone. No adverse effect was found after implantation of SM in vivo. Overall, our novel SM exhibited promising prospects for the treatment of critical-sized bone defects.

Chitosan/silk fibroin composite bilayer PCL nanofibrous mats for bone regeneration with enhanced antibacterial properties and improved osteogenic potential.

In regenerative medicine and bone tissue engineering, various composite materials are enormously popular, but the final tissue restoration outcome is not always satisfactory. In this study, bilayer-deposited multifunctional nanofiber mats were successfully fabricated with an osteogenic side of silk fibroin/poly (ε-caprolactone) (referred to as SF/PCL) and an antibacterial side of poly (ε-caprolactone)/chitosan (referred to as PCL/CS). The PCL/CS-SF/PCL (referred to as PCSP) mats exhibited biocompatible properties, sufficient hydrophilicity and mechanical properties, as well as a higher breaking strength (3.6 MPa) than the monolayer of SF/PCL mats (1.5 MPa). The antibacterial side of PCSP mats (A-layer) demonstrated ideal antibacterial potency because the survival rate of Escherichia coli (E. coli) (approximately 25 %) and Staphylococcus aureus (S. aureus) (approximately 15 %) were both significantly lower. Subsequently, the plasmid encoding runt related transcription factor 2 (Runx2) was complexed with the osteogenic side of PCSP mats (O-layer) through polyethyleneimine (PEI), thereby enhancing both osteogenesis-related gene expression and the formation of mineralized nodules. Similarly, the implantation of PCSP+Runx2 mats effectively promoted bone tissue generation in vivo. These results indicated the excellent prospects of applying PCSP mats to bone regeneration with gene delivery.

Electrically induced anisotropic assembly of chitosan with different molecular weights.

Anisotropic hydrogel is emerging as an important soft matter in the field of bionics and bioactuators, owing to its outstanding mechanical toughness and strength. Understanding the dynamic construction process of anisotropic hydrogel is beneficial for matching subsequent application. In this work, we establish an electrical field in microfluidics for the in-situ real time visualization of anisotropic assembly of chitosan, an amino polysaccharide. Polarized light microscopy is adopted to observe the dynamic growth of chitosan with different molecular weights. The results demonstrate that electrical signal has a profound influence on anisotropic assembly process of chitosan. It is interesting to notice that high oriented structure can be found in chitosan hydrogel with large molecular weight, which exhibits a dense and compact structure. This work provides a new perspective for predicting and controlling the formation of different molecular weights anisotropic chitosan hydrogels, which permit the rational design of chitosan hydrogels with excellent mechanical properties and specific functions.