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The article explains the ac susceptibility and properties exhibited by the newly developed quantum critical point mimicking series [Li.sub.x][[Mn.sub.1.96][Li.sub.0.04]][O.sub.4] (x = 0.0,0.1,0.2,0.35,0.5,0.6,0.8,1.0). The dynamical scaling observed in these compounds is also analyzed.

The present work elucidates the series of magnetic phase transitions present in the series of spinel compounds Lix[Mn1.96Li0.04]O4 (x=0.0,0.1,0.2,0.35,0.5,0.6,0.8,1.0). These systems display dynamical scaling originating from the presence of magnetic clusters that form below ∼70 K. This scaling is similar to what has been observed in the 122 quantum critical point materials containing intrinsic disorder. We study this system using ac susceptibility in order to understand how disorder leads to fragmentation of the magnetic lattice. The Li doped system's antiferromagnetic (AF) ordering sets in below ∼70 K; however, for x=1 this ordering is limited to clusters of Mn>4+> ions that are weakly coupled to each other. For the intermediate Li concentrations we observe the formation of individual spin clusters consistent with neutron scattering experiments and we find evidence for the coaligning of these clusters for T⩽20 K. A maximum in the peak of the susceptibility versus Li content between x=0.5 and x=0.35 indicates a crossover from a regime dominated by the cluster dynamics to one in which the long-range order of the delithiated λ-MnO2 phase begins to emerge. We discuss the magnetic phase diagram pertaining to short-range order in relationship to the dynamic response of these systems as measured by inelastic neutron scattering experiments. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to analyse wound biofilm from a clinical perspective. Research has shown that biofilm is the preferred microbial phenotype in health and disease and is present in a majority of chronic wounds. Biofilm has been linked to chronic wound inflammation, impairment in granulation tissue and epithelial migration, yet there lacks the ability to confirm the clinical presence of biofilm. This study links the clinical setting with microscopic laboratory confirmation of the presence of biofilm in carefully selected wound debridement samples. Method: Human wound debridement samples were collected from adult patients with chronic non-healing wounds who presented at the wound care centre. Sample choice was guided by an algorithm that was developed based on what is known about the characteristics of wound biofilm. The samples were then evaluated by light microscopy and scanning electron microscopy for the presence of biofilm. Details about subject history and treatment were recorded. Adherence to biofilm-based wound care (BBWC) strategies was inconsistent. Other standard antimicrobial dressings were used and no modern antiseptic wound dressings with the addition of proven antibiofilm agents were available for use. Results: Of the patients recruited, 75% of the macroscopic samples contained biofilm despite the prior use of modern antiseptic wound dressings and in some cases, systemic antibiotics. Wounds found to contain biofilm were not all acutely infected but biofilm was present when infection was noted. The clinical histories associated with positive samples were consistent with ideas presented in the algorithm used to guide sample selection. Conclusion: Visual cues can be used by the clinician to guide suspicion of the presence of wound biofilm. This suspicion can be further enhanced with the use of a clinical algorithm. Standard antiseptic wound dressings used in this study demonstrated limited antibiofilm efficacy. This study also highlighted a need for the clinical team to focus on expiration of dressing action and consistent practice of BBWC strategies which includes the use of proven antibiofilm agents. Declaration of interest: This work was supported by the Department of Veterans Affairs Career Development Award CDA-2 1IK2BX001701 to J.A.G. Microscopical experiments were performed in part through the use of the VUMC Cell Imaging Shared Resource (supported by NIH grants CA68485, DK20593, DK58404, DK59637 and EY08126). [ABSTRACT FROM AUTHOR]