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The article explores the dialectics of freedom in the poem "Ode on a Grecian Urn" by John Keats and its connection with the concepts of truth and beauty according to interpretations by philosophers Georg Wilhelm Friedrich Hegel and Karl Marx. It discusses Hegel's aesthetics in reading the poem as an embodiment of subjectivity and transcendence of freedom in Romantic art drawing from the Eleusinian mystery. It examines the Marxian aesthetics oriented around historicity and immanence of freedom.

In-situ (Ti, Nb)C/Ni composite coatings with liquid nitrogen cooling were fabricated on Cr12MoV die steel by laser cladding. The phase constitution, microstructure characteristics, micro-segregation behavior of elements, micro-hardness and wear resistance of coatings was explored. The results showed that the liquid nitrogen cooled coating was composed of (Ti, Nb)C, Cr 7 C 3 , Cr 23 C 6 and γ-Ni(Fe), and the growth of (Ti, Nb)C was restrained. The segregation behavior of Cr, Nb and Ti elements, crack sensitivity and pores were remarkably reduced. The nanometer chromium carbides and higher dislocation density were also observed by TEM. According to EBSD results, the coatings showed stronger textural characteristics, and the imposing liquid nitrogen cooling refined the microstructure and increased slightly the high angle grain boundaries. In addition, γ-Ni matrix in the liquid nitrogen cooled coating increased the amount of Nb, Cr and Ti elements, resulting in higher elastic modulus and average hardness. The tribochemical reaction was also occurred during the wear test from XPS results. The liquid nitrogen cooled coating showed excellent wear resistance, and it was improved 73% than air cooled coating. Unlabelled Image • (Ti, Nb)C/Ni composite coatings with liquid nitrogen cooling was fabricated on Cr12MoV die steel by laser cladding. • The imposing liquid nitrogen cooling refined the microstructure and suppressed the growth of (Ti, Nb)C particles. • The nanocrystallines and higher dislocation density were observed in the liquid nitrogen cooled coating. • The coatings showed stronger textural characteristics, and the high angle grain boundaries were also increased slightly. • The micro-hardness and wear resistance of liquid nitrogen cooled coating exhibited clear improvement. [ABSTRACT FROM AUTHOR]

Osteomyelitis is a major problem worldwide and is devastating due to the potential for limb-threatening sequelae and mortality. Osteomyelitis pathogens are bone-attached biofilms, making antibiotic delivery challenging. Here we describe a novel osteoadsorptive bisphosphonate-ciprofloxacin conjugate (BV600022), utilizing a "target and release" chemical strategy, which demonstrated a significantly enhanced therapeutic index versus ciprofloxacin for the treatment of osteomyelitis in vivo. In vitro antimicrobial susceptibility testing of the conjugate against common osteomyelitis pathogens revealed an effective bactericidal profile and sustained release of the parent antibiotic over time. Efficacy and safety were demonstrated in an animal model of periprosthetic osteomyelitis, where a single dose of 10 mg/kg (15.6 μmol/kg) conjugate reduced the bacterial load by 99% and demonstrated nearly an order of magnitude greater activity than the parent antibiotic ciprofloxacin (30 mg/kg, 90.6 μmol/kg) given in multiple doses. Conjugates incorporating a bisphosphonate and an antibiotic for bone-targeted delivery to treat osteomyelitis biofilm pathogens constitute a promising approach to providing high bone-antimicrobial potency while minimizing systemic exposure. [ABSTRACT FROM AUTHOR]

Inspired by a reactivity study between sodium trimetaphosphate (P3m) and amino acids in prebiotic chemistry, a one-step reaction with efficient purification procedure in aqueous media has been developed for the synthesis of N-phosphono-amino acids (NPAA). P3m was used to phosphorylate amino acids to NPAAwith yields of 60∼91%. The by-products, inorganic polyphosphates, were recycled to regenerate the phosphorylation reagent P3m. [ABSTRACT FROM AUTHOR]

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) presents as a morbid jawbone lesion in patients exposed to a nitrogen-containing bisphosphonate (N-BP). Although it is rare, BRONJ has caused apprehension among patients and healthcare providers and decreased acceptance of this antiresorptive drug class to treat osteoporosis and metastatic osteolysis. We report here a novel method to elucidate the pathological mechanism of BRONJ by the selective removal of legacy N-BP from the jawbone using an intra-oral application of hydroxymethylene diphosphonate (HMDP) formulated in liposome-based deformable nanoscale vesicles (DNV). After maxillary tooth extraction, zoledronate- treated mice developed delayed gingival wound closure, delayed tooth extraction socket healing and increased jawbone osteonecrosis consistent with human BRONJ lesions. Single cell RNA sequencing of mouse gingival cells revealed oral barrier immune dysregulation and unresolved proin-flammatory reaction. HMDP-DNV topical applications to nascent mouse BRONJ lesions resulted in accelerated gingival wound closure and bone socket healing as well as attenuation of osteonecrosis development. The gingival single cell RNA sequencing demonstrated resolution of chronic inflammation by increased anti-inflammatory signature gene expression of lymphocytes and myeloid-derived suppressor cells. This study suggests that BRONJ pathology is related to N-BP levels in jawbones and demonstrates the potential of HMDP-DNV as an effective BRONJ therapy. [ABSTRACT FROM AUTHOR]

Based on the background of automotive mold surface strengthening, the effects of three different enhancements on the microstructure evolution, micro-hardness and wear resistance of laser cladding cobalt-based coatings were studied. The three reinforcing materials were Co45 alloy powder, Co45/8% B4C mixed powder and Co45/8% B4C/5% Cr3C2 mixed powder. They were respectively used to conduct laser cladding on the surface of die steel with preset powder method, with laser power of 2000W and scanning speed of 4mm/s. According to the test results, the hardness and wear resistance of the cladding coating were the best when Co45/8% B4C powder was added. In addition, the study also found that B4C reacted with Cr3C2 during laser cladding to eventually generate Cr2B. The CrB2 generated for the first time during the reaction was transformed into the most stable Cr2B with an orthorhombic Fddd symmetry due to its poor stability. Therefore, the sample with Co45/8% B4C/5% Cr3C2 mixed powder was affected with a slight decrease in microhardness and wear resistance. [ABSTRACT FROM AUTHOR]

The article presents results of the green synthesis method with organic reagent free and efficient purification procedure which was developed for application in N-phosphono-amino acids. It used sodium trimetaphosphate (P3m), a cheap and easily available phosphate, as the phosphorylation reagent and came out with target compounds and inorganic phosphates.