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Nanofiber membranes via electrospinning with layered structures are frequently used for oil/water separation, thanks to their unique properties. However, challenges that involve nanofibrous membranes still remain, such as high energy consumption and unfavorable transport properties because of the densely compact structure. In this study, superelastic and robust nanofiber-based aerogels (NFAs) with a three-dimensional (3D) structure as well as tunable porosity were prepared using polyimide (PI) nanofibers via a freeze-drying process followed by the solvent-vapor treatment. The porous NFAs were further modified using trichloromethylsilane (TCMS) to generate silicone nanofilaments (SiNFs) on the surface of the PI nanofibers, which could enhance the hydrophobicity (water contact angle 151.7°) of the NFAs. The corresponding superhydrophobic NFAs exhibited ultralow density ( 99.0%), and rapid recovery under 80% compression strain. SiNFs-coated NFAs (SiNFs/NFAs) could also collect a wide range of oily solvents with high absorption capacities up to 159 times to their own weight. Moreover, surfactant-stabilized water-in-oil emulsions could also be efficiently separated (up to 100%) under the driving force of gravity, making it a promising energy-efficient technology. Additionally, SiNFs/NFAs maintained high separation efficiency throughout five separation-recovery cycles, indicating the potential of SiNFs/NFAs in the field of oil/water separation, sewage treatment, as well as oily fume purification.

The lithium metal anode has been treated as the most promising alternative in next-generation lithium-based batteries due to its ultra-high theoretical capacity, low potential and light weight. However, significant challenges such as dendrite growth and poor lifetime have severely hindered the commercialization process of lithium metal anodes. The separator not only functions as the first signal of lithium dendrite formation, but also the last barrier to prevent the battery from short-circuit, playing an irreplaceable role in lithium metal batteries. Traditional polyolefin separators have shortcomings such as poor thermal stability and poor wettability. Therefore, separator engineering is of great significance for suppressing lithium dendrite growth. In this review, we classified the recent progress of separator engineering in lithium metal batteries into four parts: (1) optimizing the performance of polyolefin membranes; (2) controlling the dendrite growth direction; (3) developing a novel separator material; (4) introducing a functional multilayer membrane. To obtain direct evidence of dendrite suppression by separator engineering, new technical means for certifying lithium deposition behaviors have also been reviewed. Finally, our conclusion and perspectives on the future research and development of lithium metal batteries are also briefly outlined.

Recombinase polymerase amplification (RPA) is a novel isothermal DNA amplification approach that has been used to detect a variety of animal and plant pathogens. However, the RPA assay is rarely used for the molecular diagnosis of plant parasitic nematodes. In this study, we developed RPA assays for the detection of four Meloidogyne spp.; Meloidogyne incognita, M. javanica, M. arenaria, and M. enterolobii. The RPA amplification step could be completed at 38 °C in 20 min without a thermal cycling instrument. The RPA assays were able to distinguish these four Meloidogyne spp. from closely related Meloidogyne species and other plant parasitic nematodes. The detection limits of the RPA assays were 10−2, 10−2, 10−1, and 10−1 dilutions of DNA from a single J2 nematode of M. incognita, M. javanica, M. arenaria, and M. enterolobii, which were less sensitive than polymerase chain reaction (PCR) detection methods. In addition, the RPA assays could detect these four Meloidogyne spp. directly from infested tomato roots. The simplicity, rapidity and practicability all indicated that the RPA assay will be an effective tool for molecular diagnosis of plant parasitic nematodes.

Antibiotics abuse and the emergence of massive drug-resistant bacteria have become the major obstacles in the medical system. Thus, designing an antibiotic-free wound dressing with antibacterial activity and decent biocompatibility is urgently desired. Herein, the sandwich-like composite hydrogel wound dressings were developed by intercalating nonwoven fabrics (NF) as the middle layer, gelatin and chitosan (Gel-CS) hydrogel loaded with Centella asiatica (CA) as the base materials. In addition, soaking strategy was employed to improve the mechanical properties of hydrogels. The hydrogels exhibited uniform microporous structure, stable mechanical property, high water absorbency, as well as water vapor transmission rate. After loading with CA, the composite wound dressing showed the sustained drug release properties in vitro and excellent antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The cytotoxicity results demonstrated that the composite hydrogels had good biocompatibility. This work indicates that the nonwoven composite hydrogels have broad application prospects in the field of medical care in the future.

Using the detection principle of infrared thermal imaging technique and the detection principle of DRH thermal conductivity tester laboratory, we investigated the infrared thermal image inspection, coefficient of thermal conductivity, apparent density, and compressive strength test on C80 high-strength concrete(HSC) in the presence and absence of polypropylene fibers under completely heated conditions. Only slight damages were detected below 400 °C, whereas more and more severe deterioration events were expected when the temperature was above 500 °C. The results show that the elevated temperature through infrared images generally exhibits an upward trend with increasing temperature, while the coefficient of thermal conductivity and apparent density decrease gradually. Additionally, the addition of polypropylene fibers with appropriate length, diameter, and quantity contributes to the improvement of the high-temperature resistance of HSC.

Electrospun nanofiber, showing large specific area and high porosity, has attracted much attention across various fields, especially in the field of air filtration. The small diameter contributes to the construction of filters with high-filtration efficiency for fine particulate matter (PM), however, along with an increase in air resistance. Herein, composited nanofiber aerogels (NAs), a truly three-dimensional (3D) derivative of the densely compacted electrospun mat, were constructed with the blocks of polytetrafluoroethylene–polyamideimide (PTFE–PAI) composite nanofiber and polyimide (PI) nanofiber. PI/PTFE–PAI NAs with hierarchically porous architecture and excellent mechanical properties have been obtained by thermally induced crosslink bonding. Results indicated that sintering at 400 °C for 30 min could complete the decomposition of polyethylene (PEO) and imidization of polyamic acid (PAA) into PI, as well as generate sufficient mechanical bonding between adjacent nanofibers in the NAs without extra additive. The well-prepared PI/PTFE–PAI NAs could withstand high temperature up to 500 °C. In addition, the filtration tests illustrated that the composite NAs had an excellent performance in PM filtration. More importantly, the filtration behavior could be adjusted to meet the requirements of various applications. The excellent thermal stability and high-filtration efficiency indicated its great potential in the field of high-temperature air filtration.

We previously reported that Prunella vulgaris aqueous extract (PVAE) promotes hepatic glycogen synthesis and decreases postprandial hyperglycemia in ICR mice. Inflammatory cytokines play a critical role in the pathogenesis of diabetes. This study was designed to examine whether PVAE has a protective effect on IL-1β-induced apoptosis in INS-1 cells. INS-1 pancreatic β cells were plated at 2×10(6)/ml and treated with PVAE (100 µg/ml) 30 min before the cells were challenged with IL-1β (10 ng/ml). Untreated INS-1 cells served as control. INS-1 cell cytotoxicity was examined by MTT and lactate dehydrogenase (LDH) activity assays. Caspase-3 activity and activation of the apoptotic signaling pathway were analyzed by western blotting. NF-κB binding activity was examined by EMSA. The levels of inflammatory cytokines in the supernatant were measured by ELISA. IL-1β treatment significantly induced INS-1 cell death by 49.2%, increased LDH activity by 1.5-fold and caspase-3 activity by 7.6-fold, respectively, compared with control cells. However, PVAE administration significantly prevented IL-1β-increased INS-1 cell death and LDH activity and attenuated IL-1β-increased caspase-3 activity. Western blot data showed that PVAE also significantly attenuated IL-1β-increased Fas, FasL and phospho-JNK levels in the INS-1 cells. In addition, PVAE treatment significantly attenuated IL-1β-increased NF-κB binding activity and prevented IL-1β-increased TNF-α and IL-6 expression in INS-1 cells. Our data suggest that PVAE has a protective effect on IL-1β-induced INS-1 cell apoptosis. PVAE also attenuates IL-1β-increased NF-κB binding activity and inflammatory cytokine expression in INS-1 cells. PVAE may have a benefit for type I diabetic patients.

A method to readily isolate antibodies that bind to only one member of a family of homologous proteins is described. A library of different single chain antibody fragments can be displayed on the surface of a bacteriophage vector. Individual antibodies from this library recognizing a particular protein from a family of homologous proteins can be readily isolated by a two-step affinity screening process. In the first step antibodies which bind specifically to the undesired proteins or to homologous regions of the proteins are removed. In the second step, those antibodies specifically recognizing the desired protein are then isolated. Using this procedure and starting with a naive antibody library, a single chain antibody fragment specific to the blood clotting protein, Protein C, which did not recognize either of the homologous proteins, Factor IX or Factor X, was isolated. Similarly an antibody specific to Factor IX, but not Factor X or Protein C, was also isolated. The isolated antibodies can be readily produced, purified, and affixed to sepharose beads for affinity chromatography of the blood clotting factors. One of the key advantages to this procedure over conventional monoclonal antibody isolation is that the antibodies are isolated and produced in vitro so a broad range of related proteins, toxins, viruses, or other products can be targeted.

Electrical signals are used to trigger the entrapment and release of antibiotics on the surface of titanium plate. The entrapment of antibiotics relies on the electrochemically induced pH gradient generated at the titanium surface that allows the gelation of an aminopolysaccharide chitosan and codeposition of vancomycin, a common antibiotic, within chitosan gel. The release of vancomycin is controlled by an anodic signal imposed to the titanium plate that causes a pH decrease and erosion of chitosan gel. We show that the on demand entrapment and release of vancomycin at the surface of titanium plate is fundamentally altered and controlled by voltage. We expect that this rapid, mild and facile electrochemical process for antibiotics loading and release will find applications in controlled drug release from titanium implants.

Protein C (PC) is the pivotal anticoagulant and antithrombotic in the human coagulation cascade. PC deficiency can result in major medical problems such as deep vein thrombosis (DVT), leading to tissue oxygen deprivation. PC treatment has no bleeding or skin necrosis problems because it circulates in the blood as a zymogen and is only activated when and where it is needed. One source of PC is transgenic animal milk. The major components in the milk, such as alpha-casein, beta-casein, kappa-casein, alpha-lactalbumin and beta-lactoglobulin, are proteins that must be separated from PC. Immobilized metal affinity chromatography (IMAC) is an inexpensive separation technology with relatively high specificity, and it has great potential for difficult protein separations. After systematic studies of different chelator, metal ion and buffers, the combination of iminodiacetic acid (IDA) and Fe was found to be effective to separate PC from major milk components. alpha-Lactalbumin and beta-lactoglobulin fell through the column in the starting buffer. PC was eluted. alpha-Casein, beta-casein, kappa-casein remained bound in the column after PC elution. This technology might be applied for PC separation from transgenic animal milk. It is very important for PC production in large quantities and at low cost to treat PC-deficient patients.