Quantum Magnetic Properties in Perovskite with Anderson Localized Artificial Spin-1/2

Quantum magnetic properties in a geometrically frustrated lattice of spin-1/2 magnet, such as quantum spin liquid or solid and the associated spin fractionalization, are considered key in developing a new phase of matter. The feasibility of observing the quantum magnetic properties, usually found in geometrically frustrated lattice of spin-1/2 magnet, in a perovskite material with controlled disorder is demonstrated. It is found that the controlled chemical disorder, due to the chemical substitution of Ru ions by Co-ions, in a simple perovskite CaRuO3 creates a random prototype configuration of artificial spin-1/2 that forms dimer pairs between the nearest and further away ions. The localization of the Co impurity in the Ru matrix is analyzed using the Anderson localization formulation. The dimers of artificial spin-1/2, due to the localization of Co impurities, exhibit singlet-to-triplet excitation at low temperature without any ordered spin correlation. The localized gapped excitation evolves into a gapless quasi-continuum as dimer pairs break and create freely fluctuating fractionalized spins at high temperature. Together, these properties hint at a new quantum magnetic state with strong resemblance to the resonance valence bond system.Comment: 8 pages, 6 figure

Land and water management in rainfed farming systems

Land and water are the key elements of the resource-base of rainfed farming systems and strategies for effective management of these resources are intimately linked. This paper reviews ICRISAT's research approach for developing improved land and water management practices and their integration with other aspects of farming systems. The small watershed-based farming systems approach which holds s good promise for management of Vertisols is discussed. The present status of research on.Alfisol management, tank irrigation and runoff modeling,at.ICRISAT has been reviewe

Ear and hearing care programs for First Nations children: a scoping review

Background: Ear and hearing care programs are critical to early detection and management of otitis media (or middle ear disease). Otitis media and associated hearing loss disproportionately impacts First Nations children. This affects speech and language development, social and cognitive development and, in turn, education and life outcomes. This scoping review aimed to better understand how ear and hearing care programs for First Nations children in high-income colonial-settler countries aimed to reduce the burden of otitis media and increase equitable access to care. Specifically, the review aimed to chart program strategies, map the focus of each program against 4 parts of a care pathway (prevention, detection, diagnosis/management, rehabilitation), and to identify the factors that indicated the longer-term sustainability and success of programs. Method: A database search was conducted in March 2021 using Medline, Embase, Global Health, APA PsycInfo, CINAHL, Web of Science Core Collection, Scopus, and Academic Search Premier. Programs were eligible or inclusion if they had either been developed or run at any time between January 2010 to March 2021. Search terms encompassed terms such as First Nations children, ear and hearing care, and health programs, initiatives, campaigns, and services. Results: Twenty-seven articles met the criteria to be included in the review and described a total of twenty-one ear and hearing care programs. Programs employed strategies to: (i) connect patients to specialist services, (ii) improve cultural safety of services, and (iii) increase access to ear and hearing care services. However, program evaluation measures were limited to outputs or the evaluation of service-level outcome, rather than patient-based outcomes. Factors which contributed to program sustainability included funding and community involvement although these were limited in many cases. Conclusion: The result of this study highlighted that programs primarily operate at two points along the care pathway—detection and diagnosis/management, presumably where the greatest need lies. Targeted strategies were used to address these, some which were limited in their approach. The success of many programs are evaluated as outputs, and many programs rely on funding sources which can potentially limit longer-term sustainability. Finally, the involvement of First Nations people and communities typically only occurred during implementation rather than across the development of the program. Future programs should be embedded within a connected system of care and tied to existing policies and funding streams to ensure long term viability. Programs should be governed and evaluated by First Nations communities to further ensure programs are sustainable and are designed to meet community needs

Stabilization of α-conotoxin AuIB: Influences of disulfide connectivity and backbone cyclization

alpha-Conotoxins are peptides isolated from the venom ducts of cone snails that target nicotinic acetylcholine receptors (nAChRs). They are valuable pharmacological tools and have potential applications for treating a range of conditions in humans, including pain. However, like all peptides, conotoxins are susceptible to degradation, and to enhance their therapeutic potential it is important to elucidate the factors contributing to instability and to develop approaches for improving stability. AuIB is a unique member of the alpha-conotoxin family because the nonnative "ribbon'' disulfide isomer exhibits enhanced activity at the nAChR in rat parasympathetic neurons compared with the native "globular'' isomer. Here we show that the ribbon isomer of AuIB is also more resistant to disulfide scrambling, despite having a nonnative connectivity and flexible structure. This resistance to disulfide scrambling does not correlate with overall stability in serum because the ribbon isomer is degraded in human serum more rapidly than the globular isomer. Cyclization via the joining of the N- and C-termini with peptide linkers of four to seven amino acids prevented degradation of the ribbon isomer in serum and stabilized the globular isomers to disulfide scrambling. The linker length used for cyclization strongly affected the relative proportions of the disulfide isomers produced by oxidative folding. Overall, the results of this study provide important insights into factors influencing the stability and oxidative folding of alpha-conotoxin AuIB and might be valuable in the design of more stable antagonists of nAChRs. Antioxid. Redox Signal. 14, 87-95

Impact of routine laboratory culture media on in-vitro biofilm formation of Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus faecalis

Objectives: This study was aimed to determine the efficacy of four routine laboratory culture media onbiofilm formation of Pseudomonas aeruginosa, Staphylococcus aureus and Enterococcus feacalis.Methods: A sterile flat bottom 96 well plate was inoculated using 0.5 McFarland equivalent standardcell suspension of P. aeruginosa, S. aureus and E. feacalis and the growth rate of planktonic cells wasquantified by measuring the optical density (OD492) at two hour intervals. Influence of culture mediumon adhesion of bacteria as an initial step of biofilm formation in the presence of four culture media(Nutrient broth (NB), Brain Heart Infusion (BHI) broth, Luria-Bertani (LB) broth and RPMI 1640) wasquantified using MTT (3-[4, 5- dimethylthiazole-2-yl]-2, 5- diphenyltetrazolium bromide) assay after90 minutes adhesion. Biofilms of P. aeruginosa, S. aureus, E. feacalis and their 1:1 mixed biofilmswere developed and the growth was quantified using MTT metabolic activity at 24 hour time intervals.Scanning electron microscopy (SEM) was performed to assess the ultrastructure.Results: On comparing the relative growth of the bacteria in different culture media, the maximumgrowth of all three planktonic cultures was achieved using BHI broth. All mono species and mixedspecies cultures exhibited their maximum adhesion in the presence of RPMI 1640. All biofilm exhibitedthe maximum growth in BHI broth. SEM imaging had shown the enhanced growth of ultrastructure ofthe biofilm with the presence of BHI broth.Conclusions: The maximum planktonic and biofilm growth was achieved with BHI broth. However,bacterial adhesion was enhanced in the presence of RPMI 1640