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A novel process for efficient para ethyl phenol production was provided via the selective cleavage of pCA8 linkage of lignin.

Periprosthetic infection remains a challenging clinical complication. We investigated the antibacterial properties of pure (99.9%) magnesium (Mg) in vitro and in an in vivo rat model of implant-related infection. Mg was highly effective against methicillin-resistant Staphylococcus aureus-induced osteomyelitis and improved new peri-implant bone formation. Bacterial icaA and agr RNAIII transcription levels were also assessed to characterize the mechanism underlying the antibacterial properties of the Mg implant.A rtificial metal implants are widely used to repair bone injury due to fractures, tumor resection, and other causes. However, periprosthetic infections (PPI) are a clinically challenging complication, as the biomaterial implant surfaces serve as substrates for bacterial adhesion, colonization, and biofilm formation (1, 2). Prolonged antimicrobial treatment, implant removal, and surgical revision are often necessary to cure PPI, which leads to increased patient morbidity and places a substantial health care burden on society. Conventional PPI prevention relies on systemic antibiotics, which possess several disadvantages: (i) it is difficult to achieve an effective local antibiotic concentration without risking systemic toxicity, (ii) therapy is ineffective once the adherent bacteria have formed a biofilm on the implant surface, and (iii) they increase the emergence of antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA), a common osteomyelitis-inducing pathogenic bacterium. Thus, many studies have focused on the development of novel medical biomaterials with antibacterial properties, such as metal implants, that prevent and/or treat implant-associated infection (3-6).Pure magnesium plates were first introduced as orthopedic implants in 1907. Since then, this biodegradable magnesiumbased metal and its alloy have been widely investigated for their utility as implant materials suitable for bone and cardiovascular applications due to their cytocompatibility and mechanical properties similar to those of natural bone (7-10). Previous investigations have found that the corrosion products of Mg degradation possess in vitro antibacterial function because they increase local alkalinity (11). These characteristics suggest that Mg-based metal could provide clinical utility as an orthopedic implant to prevent implant-associated infections. We investigated the in vitro and in vivo antibacterial properties of pure Mg (99.9%) against MRSA. Rat models of implant-related osteomyelitis (Sprague-Dawley rats) were implanted with pure Mg intramedullary nails. The efficacy of the nails for treating osteomyelitis and the amount of new peri-implant bone formation were evaluated. We also assessed bacterial icaA and agr RNAIII transcription to identify the mechanism underlying the antibacterial properties of pure Mg.The in vitro antibacterial efficiency of Mg and titanium (Ti) sample discs ( ϭ 15 mm) was analyzed using the spread plate method (12, 13) after coculturing with MRSA (ATCC 43300) for 6...

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Magnetic fields enable dexterous, precise, and real‐time control of ferromagnetic materials. However, most materials, including glasses, organics, and metals, are nonmagnetic and often do not respond to a magnetic field. Here, a transitional ferrofluid (TF) made by embedding magnetic iron particles into pure gallium through the treatment of highly concentrated HCl solutions, as well as its switchable interlocking force to objects during the phase change, is introduced to achieve magnetic manipulation of non‐magnetic objects. A gripper made by liquid TF enables intimate contact with arbitrarily shaped objects and then generates a strong interlocking force of as high as 1168 N (using only 10 g TF) upon solidification at room temperature, which can be reversibly eliminated (F < 0.01 N) through melting. Owing to electrical conductivity and magnetism, a solid TF can be melted through electromagnetic induction heating. By coupling the switchable physical force during the phase transition and magnetism of TF, embedded non‐magnetic objects can be manipulated using an applied magnetic field and become impervious to magnetic stimuli again after heating and releasing the TF. This study is expected to inspire numerous potential applications in the reversible magnetic actuation of soft robotics, remote operation systems, drug delivery, and liquid grippers.