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[Display omitted] Early diagnosis of bacterial infection and tracking of treatment effect are of great importance for developing a "sense-and-treat" integrated system. Herein, we developed a bacteria-triggered, portable, wearable and colorimetric film-based band-aid (FBA) for closed-loop monitoring and light-controlled therapy of wound infection. FBA with high photothermal conversion efficiency of 52.56% was prepared by wrapping Bi 2 S 3 nanoflowers (BS NFs) loaded with rhodium nanoparticles (Rh NPs) and bromothymol blue (BTB) into LB agar film, integrating bacteria-triggered color change, photothermal/photodynamic therapy (PTT/PDT) synergistic bactericidal therapy and agar-based band aid in one intelligent system. Initially, FBA effectively simulates the pH sensing mechanism, and monitors the occurrence of bacterial infections within 5 min through color changes of Staphylococcus aureus (S. aureus) from blue to yellow and Escherichia coli (E. coli) from yellow to blue. Additionally, the short-term and controlled antibacterial strategy of "one light dual-mode responses" (photothermal and photodynamic responses) was implemented with the introduce of near-infrared (NIR). Ultimately, the effectiveness of FBA was fully validated in the monitoring and treating of S. aureus -infected mouse wounds. Notably, the designed FBA decisively abandoned off-target side effects maximizing the treatment effect and nakedly tracking therapeutic situation in real time, contributing an effective antibacterial alternative strategy for reducing the use of antibiotics. To the best of our knowledge, such integrated system is still unreported on film-fixed model. In view of the advantages of the low cost and convenience of the simple device, the integrated design is expected to provide a solution for the development of a closed-loop biomedical system combining diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Abstract: We describe an involution on a set of sequences associated with lattice paths with north or east steps constrained to lie between two arbitrary boundaries. This involution yields recursions (from which determinantal formulas can be derived) for the number and area enumerator of such paths. An analogous involution can be defined for parking functions with arbitrary lower and upper bounds. From this involution, we obtained determinantal formulas for the number and sum enumerator of such parking functions. For parking functions, there is an alternate combinatorial inclusion–exclusion approach. The recursions also yield Appell relations. In certain special cases, these Appell relations can be converted into rational or algebraic generating functions. [Copyright &y& Elsevier]

This study presented a facile approach for fabricating oil-in-water lavender essential oil nano-emulsions (LEONs) with excellent antibacterial and antioxidant activities. Besides, LEONs with different LEO content (50, 100, 200 and 300 μL/10 mL) were incorporated to the matrix of gelatin (GL) for preparing multifunctional GL-LEONs films, which exhibited strong antibacterial properties against Staphylococcus aureus , Escherichia coli and Listeria monocytogenes , as well as excellent antioxidant activities. Additionally, the GL-LEONs films exhibited sustained release characteristics, excellent UV light barrier performances and good heat-sealing properties. Furthermore, the GL-LEONs films were applied to the preservation of cherry tomatoes at 25 ± 2 °C for 7 days. The results revealed that the deterioration of cherry tomatoes packaged with the GL-LEONs films was suppressed during storage, which mainly reflected in reducing weight loss, delaying the degradation of titratable acids and phenolic components, and inhibiting the growth of microorganisms. • Oil-in-water lavender essential oil nano-emulsions (LEONs) were fabricated. • LEONs improved gelatin films antibacterial and antioxidant activities. • Gelatin-LEONs films exhibited sustained release and good heat-sealing properties. • Gelatin-LEONs films effectively maintained the freshness of cherry tomatoes. [ABSTRACT FROM AUTHOR]

In this paper, the natural antibacterial agent cinnamaldehyde (CA) was made into nanoemulsions to improve its water solubility. Subsequently, the active gelatin (GL-CA-Vc) films with antibacterial and antioxidant activities were prepared by combining silver carp skin gelatin with CA nanoemulsions and vitamin C (Vc). Compared with the gelatin control (GL-Control) film, the thickness, roughness and water vapor permeability (WVP) of active films increased significantly. In addition, the elongation at break (EAB) and light barrier property of active films were also enhanced. The antibacterial and antioxidant activities of active films were related to the content of active additives. The film containing 100 mg of CA and 50 mg of Vc (GL-100CA-50Vc) had good light barrier property and a high EAB (158.00 ± 12.51%). What's more, the inhibition rate of GL-100CA-50Vc film against Pseudomonas aeruginosa was 55.97 ± 4.25%, and the free radical scavenging rate of the film to ABTS and DPPH was 96.26 ± 0.72% and 95.74 ± 0.20% respectively, which indicated that the film had good antibacterial and antioxidant activities. • Active films were prepared by combining fish gelatin with CA nanoemulsions and Vc. • GL-CA-Vc films possessed good EAB, ultraviolet and visible light barrier capacity. • The prepared active films showed excellent antioxidant and antibacterial activities. [ABSTRACT FROM AUTHOR]

Developing a facile method to fabricate new heterogeneous Metal-Organic Framework (MOFs) based catalysts with high catalytic activity and stability has drawn significant attention. Herein, we demonstrate a simple in-situ pyrolysis reduction strategy to fabricate a novel three-dimensional (3D) Cu-based catalyst, which displays an outstanding performance for the decomposition of 4-nitrophenol (4-NP). Detailed characterization including SEM, FTIR, XPS, ICP-OES, HRTEM, SAED, XRD and BET confirmed the formation of the Cu/C porous composites (Cu/C-PC). Taking advantage of enormous Cu particles in the composite as well as ultrahigh surface area (196.7 m2/g) of carbon support, Cu/C-PC presents prominent catalytic activity for the hydrogenation reduction 4-NP to 4-aminophenol (4-AP) with apparent rate constant (K app) of 0.0267 s−1 (the ratio of K app to the catalyst amount is 119 s−1 g−1), which is dramatically higher than that previous reports. On the contrary, after being washed successively (Cu/C-PC-AW) by FeCl 3 , HCl aqueous solution and deionized water, the Cu/C porous composite materials exhibit fairly weak catalytic activity. The catalytic performance of Cu/C-PC is better than Cu, Cu 2 O and CuO nanoparticles as well as other catalysts in previous reports. Furthermore, Cu/C-PC shows excellent reusability, indicating its potential applications in treatment of water pollution. [ABSTRACT FROM AUTHOR]

Polymerase chain reaction (PCR) is one of the most common methods for rapid monitoring of foodborne pathogens; however, it requires purified nucleic acid as a template. Conventional nucleic acid purification is a time-consuming and laborious process. To overcome this, we developed polydopamine nanospheres (PDA NPs)-assisted direct PCR for detecting Escherichia coli O157:H7 (E. coli O157:H7). PDA NPs significantly enhanced PCR efficiency because of their strong interaction with PCR reagents, including polymerase and primers, thereby enabling regulation of the PCR performance. The optimal concentration and diameter for PDA NPs were 0.10 μg/μL and 504 nm, respectively. The PDA NPs-assisted direct PCR exhibited high sensitivity in E.coli O157:H7 detection. The detection limit of PDA NPs-assisted direct PCR was 6.7 × 104 CFU/mL, which was 10-fold lower than that of direct PCR (6.7 × 105 CFU/mL). Moreover, the sensor demonstrated excellent selectivity against E. coli O157:H7, with a negative reaction to eight other common pathogens. Most importantly, the PDA NPs-assisted direct PCR detected the order of 104−5 CFU/mL E.coli O157:H7 in milk, beef, and watermelon samples. No cultural enrichment was required, with the whole process taking <3 h. Therefore, PDA NPs-assisted direct PCR has tremendous potential in the rapid and sensitive detection of pathogens. [Display omitted] • Polydopamine nanospheres-assisted direct PCR was developed. • Direct PCR shortens the detection time due to the DNA extraction step being omitted. • Polydopamine nanospheres can improve PCR efficiency by interaction with PCR reagents. • The sensor was used in real samples for E. coli O157: H7 detection with good results. [ABSTRACT FROM AUTHOR]