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Two different products from the reaction between 2-formylphenylboronic acid and benzhydrazide: benzoyl hydrazone versus dimer
No full textFree to read onlineThe reaction of benzhydrazide and 2-formylphenylboronic in H2O at ambient temperature afforded the benzoyl hydrazone (E)-{2-[(2-benzoylhydrazinylidene)methyl]phenyl}boronic acid, C14H13BN2O3 (5). However, when the reaction was performed in EtOH at ambient temperature, a dimer product, namely, {oxybis[benzo[d][2,3,1]diazaborinine-1,2(1H)-diyl]}bis(phenylmethanone), C28H20B2N4O3 (6), is the sole product isolated. Both compounds were characterized using 1H, 13C and 11B NMR spectroscopy, high-resolution mass spectrometry (HRMS) and single-crystal X-ray diffraction following crystallization from hot DMF/H2O for 5 and from hot CH3CN for 6. Benzoyl hydrazone 5 crystallized in the orthorhombic space group Pbca and revealed a strong intramolecular hydrogen-bonding interaction between the boranol O atom and hydrazonoyl N atom [H...N = 1.734 (18) Å, O...N = 2.6139 (12) Å and O-H...N = 157.4 (15)°], ensuring a near-planar benzhydrazonoyl moiety. Benzoyl hydrazone 5 packs in the solid state in dimeric assemblies through intermolecular boranol hydrogen bonds, that are further extended to two-dimensional sheets by intermolecular hydrazonoyl nitrogen to hydrazonoyl oxygen hydrogen bonds. Dimer 6 crystallized in the monoclinic space group C2/c with the borinine O atom lying on the twofold rotational axis. In contrast to the structure of benzoyl hydrazone 5, dimer 6 lacks hydrogen-bond donors and packs with an absence of intermolecular hydrogen bonding. A dative bond between the B centre and an adjacent carbonyl O atom is observed for dimer 6 [B-O = 1.574 (2) Å], enabling the formation of a [3.3.1]bicyclic system at its core. This article provides unambiguous evidence that, depending on the conditions employed, the reaction between 2-formylphenylboronic acid and benzhydrazide produces benzoyl hydrazone 5 or dimer 6 rather than 2-benzoyl-1-hydroxybenzo[d][2,3,1]diazaborine (2), despite literature reports suggesting that the latter is the case.James P. Chakiris, Christopher J. Sumby, Douglas A. Brooks, Trent D. Ashton and Shane M. Hicke
Systematic review of wild birds as reservoirs of antimicrobial resistance: Implications for roof-harvested rainwater safety
No full textThis review investigates the role of wild birds as reservoirs and vectors of antimicrobial-resistant bacteria and antimicrobial resistance genes, and the implications for human health via contamination of harvested rainwater. A systematic literature review revealed that urban-adapted birds, especially gulls and pigeons, frequently carry clinically relevant antimicrobial-resistant bacteria including Carbapenem resistant Enterobacterales (CRE), multidrug-resistant Escherichia coli, extended-spectrum beta-lactamases (ESBL)-producing E. coli, and methicillin-resistant Staphylococcus aureus (MRSA) as well as colistin and macrolide-lincosamide-streptogramin (MLS) resistance genes. Due to urbanisation, these birds often forage in contaminated urban environments such as landfills, sewage sites and waste deposits, which increases their exposure to antimicrobial-resistant bacteria and antimicrobial resistance genes raising concerns about their increasing role in the environmental dissemination of AMR. Roof-harvested rainwater, a growing alternative water source amid climate change and water scarcity, can be contaminated by bird droppings containing antimicrobial-resistant bacteria and antimicrobial resistance genes. Despite its widespread use, harvested rainwater remains largely unregulated, presenting a public health risk. The findings from this review highlights the need for increased monitoring, targeted research, and improved risk management strategies to address AMR transmission from birds to humans via environmental pathways such as harvested rainwater.Mira Cooper-Beknazarova, Ben van den Akker, Barbara Drigo, Kirstin Ross, Harriet Whiley, Craig R. William
Measurement of dynamic stress using linear and nonlinear acoustoelastic effects due to colinear wave mixing
No full textPublished online 22 August 2025This paper investigates a new method to evaluate dynamic stress in plate or shell-like components due to propagation of elastic waves. The proposed method is based on collinear mixing of the stress wave with a high frequency (probe) wave, which is excited in the ultrasonic frequency range. The wave interactions generate linear and nonlinear responses such as the changes of the group velocity of the probe wave and generation of higher-order harmonics, respectively. A three-dimensional finite element (FE) model is developed to investigate and link these changes to the magnitude of the dynamic stress excited by the elastic waves. In the current work two S0 Lamb wave modes at relatively low and high frequences were utilised to demonstrate the proposed method, which can be extended to the measurement of dynamic stress generated by different elastic wave modes or vibrations. The numerical results have been validated by an experimental study confirming that the nonlinear effects are much more sensitive to the induced dynamic stress rather than the corresponding linear changes of the wave velocities. In addition, two parametric studies are conducted using the experimentally verified FE model. These studies are focused on the effects associated with the stress variation in the mixed region and the wavelength ratio of the probe wave to the pump waves on the dynamic stress evaluation with the proposed method.Tianyi Wang, Ching Tai Ng, Andrei Kotouso
Pyrazole carbodithiolate-driven iterative RAFT single-additions
No full textIn this Communication, we comprehensively investigated substituent effects relevant to iterative reversible activation fragmentation chain transfer (RAFT) single unit monomer insertion (SUMI) reactions. Through the use of the pyrazole carbodithiolate (PCDT) “Z-group” as the chain transfer component in RAFT SUMI, we show the importance of “Z-group” effects and its interplay with “R-group” (the carbon-centred radical precursor) effects. We also expanded the scope of RAFT SUMI to new monomer types and sequences thereof. As such, the C–S bond dissocation/reformation steps were found to be crucial factors in SUMI, and it was found that general substituent effects must be wholistically examined for every step of this reaction. This stands in contrast with conventional knowledge of RAFT polymerisation, where the main consideration is often centred around the propagation stage, i.e., the key C–C bond formation step. Indeed, contrary to SUMI, the latter characteristic was observed in the analogous alternating copolymerisation.Karen Hakobyan, Benjamin Noble and Jiangtao X
Principle 11: Collaboration Over Competition: Enacting Academic Method Writing Through Collaborative Authorship
No full textCollaboration over competition is an important Gentle Academic prin- ciple, fostering innovation, knowledge sharing, and interdisciplinary discoveries. This chapter explores this principle through an innovative methodological approach: collaborative authorship as a form of academic method writing. By engaging schol- ars who are actively involved in various types of collaboration to co-author relevant sections, this chapter not only critically discusses but also embodies the principles of collaborative academic partnerships. Drawing on both existing literature and the authors’ lived experiences, the chapter examines six key areas of academic collabo- ration: intra-departmental, cross-disciplinary, university-industry, university-to- university, international, and intergenerational partnerships. For each type, the authors analyse the practicalities, challenges, and effective strategies, providing theoretical and practical perspectives. The chapter addresses issues that can hinder or facilitate collaboration, such as tenure processes, intellectual property concerns, and the role of digital platforms and physical spaces in fostering collaboration. This chapter will also explore strategies and policy implications for motivating academ- ics to engage in collaborative work.Kelly-Ann Allen, Rico Alokuzay, Salim Al Maqbali, Nouf Alsaadi, Christopher Boyle, Bonnie Bozorg, Ashleigh Collier, Victor Counted, Shari Dudda, Jessica Hofmann, Shannon G. Kuschel, Sandra Ofei-Ferri, Amanda-Lee Pitzer, Tom Porta, Natalie Vannini, Alexa von Hagen, and Pauline Winkle
Management, use and documentation of off-label antimicrobials in the operating theatre: A survey of Australian hospital pharmacists
No full textBackground Optimising antimicrobial use during surgery is essential for preventing surgical site infections, ensuring patient safety and minimising the risk of antimicrobial resistance. To investigate the management, use and documentation of ‘off-label’ antimicrobials in Australian operating theatres (OT). Methods A cross-sectional online survey of hospital pharmacists with expertise in antimicrobial stewardship, surgery or and/or medication safety. Demographic and quantitative questions were analysed using descriptive statistics. Free-text responses underwent reflexive thematic analysis. Results Responses from 61 Australian hospital pharmacists were analysed. 83 % of survey participants reported that ceftriaxone was stocked in OT, with 70 % and 62 % stocking IV amoxicillin-clavulanate and piperacillin-tazobactam respectively. Vancomycin (34 %), rifampicin (18 %) and gentamicin (16 %) were the most commonly used antimicrobials for wound irrigation. Over half (51 %) of participants reported seeing vancomycin powder applied directly to surgical sites. Thematic analysis of free-text responses generated three dominant themes: surgical staff work-arounds, risks to patient safety, and detached or unclear pharmacist role in OT. Conclusion Broad-spectrum antimicrobials are used topically as washes, soaks, and applied directly to surgical sites, however the extent of this practice is unclear due to poor documentation. There is wide variation between hospitals regarding which antimicrobials are kept in OT, with inconsistent compliance to systems restricting use in this setting. Opportunities to improve the use of broad-spectrum antimicrobials include: better utilisation of automated dispensing cabinets to track use and facilitate audits, embedding of pharmacists in OT to improve management, and policies to ensure documentation and patient consent for use outside of evidence-based guidelines.Nadine T. Hillock, Matthew Rawlins, Edward Raby, Courtney Ieran
Semi-automated genomic newborn screening highlights complexities in reporting
No full textOnlinrPublNewborn screening programs are instrumental in the early detection of treatable conditions in the first days of life. By integrating genomic approaches, there is potential to expand the range of conditions included in these programs. As part of a research study, NewbornsInSA, we validated a genomic newborn screening workflow. Analysis of whole-genome sequencing data was restricted to a virtual panel of 613 genes, selected through engagement with local clinical teams. We assessed the workflow’s performance using retrospective samples with known variant status. To reduce manual curation time, bioinformatics scripts were developed to auto-classify cases into those with no findings and those requiring manual review. We report on early findings from applying this workflow to a prospectively recruited cohort in which five reportable findings have been made to date. We discuss reporting challenges encountered in genes associated with multiple conditions, with incomplete penetrance, or variants associated with only mild phenotypes.Ayesha Chowdhury, Shashikanth Marri, Lucy Anastasi, Alex Ashenden, Tomas Rozek, Jinghua Feng, Lucas DeJong, Rosalie Kenyon, Dominik Kaczorowski, Hung Nguyen, Khoa Lam, Kirsty Stallard, Tracy Merlin, Enzo Ranieri, Sunita De Sousa, Nicholas Smith, Abhi Kulkarni, Benjamin Saxon, Drago Bratkovic, Christopher Barnett, Carol Wai-Kwan Siu, Hamish S. Scott, Jovanka King and Karin S. Kassah
Effect of off-axis laser incidence on residual stress in laser-based directed energy deposition of 316L stainless steel
No full textResidual stress limits dimensional accuracy and service performance in the Laser-based Directed Energy Deposition (DED-LB) of 316L stainless steel. Process-integrated mitigation was demonstrated using off-axis (oblique-incidence) laser delivery. A 20 mm-thick multilayer build was characterized by neutron diffraction, neutron tomography, electron backscatter diffraction (EBSD), and Vickers macrohardness mapping. Residual stresses were confined to ±100 MPa, with interior tension and surface-adjacent compression; neutron tomography measured ∼0.001% porosity for pores ≥50μm. Hardness of 150–230 HV20 colocated with compressive zones, and EBSD showed elongated columnar grains with position-dependent texture. The reduced stress state is attributed to the enlarged projected footprint and lower peak irradiance of off-axis delivery, which spread heat laterally, reduce the thermal gradient (G) and cooling rate ( _ T), and favor conduction-mode melting. These results establish off-axis DED-LB as a route to in situ residual-stress control and microstructural tailoring while maintaining negligible resolved porosity in additively manufactured 316L components. The bulk, through-thickness maps and datasets provide component-scale validation to calibrate models and support process qualification.Andre Hatem, Anthony Roccisano, Christiane Schulz, Thomas Schlaefer, Vladimir Luzin, Filomena Salvemini, Ashok Meghwal, Andrew Siao Ming Ang, and Colin Hal
Mid-Neoproterozoic extensional tectonics in the Larsemann Hills, East Antarctica: Implications for Indo-Antarctic correlation in Rodinia
No full textThe supercontinents Rodinia and Gondwana are believed to have assembled through orogenic events at ∼1000 Ma and ∼550 Ma, respectively. The Larsemann Hills, part of the extended Rayner Complex of East Antarctica, is a Neoproterozoic granulite terrane that was a part of both supercontinents. The tectonic evolution of the terrane in the Rodinia to Gondwana interval remains uncertain. This study integrates new field, microstructural, metamorphic and geochronological information to unveil a previously undocumented mid-Neoproterozoic thermo-tectonic event in the Larsemann Hills. Granulite facies metamorphism (M₁), synchronous with the deformation, D₁, is interpreted to have occurred in the Larsemann Hills at ∼1000 Ma, followed by a crustal shortening (D₂) event that continued from ∼990–900 Ma, signifying the incorporation of the Rayner crustal unit into Rodinia. Subsequent mid-Neoproterozoic extensional deformation (D₃), characterized by NW-SE trending S₃ shear zones, reoriented pre-existing structural fabrics. The extensional deformation operated under amphibolite facies metamorphic conditions (M₂) and resulted in a post-peak decompressive P-T trajectory. Usingle bondPb LA-ICPMS dates on zircons separated from metapelites within high D₃ strain zone yield clusters at ∼700 Ma; zircons immediately adjacent to the shear zone yield ages around ∼990–900 Ma. A thermal overprint at ∼550 Ma is evident but weakly manifested in the western Larsemann Hills, with no unambiguously correlatable structural or metamorphic evidence, suggesting distance from the Gondwana orogenic front. The extensional deformation documented here is contemporaneous with extension in the northern Eastern Ghats Province, India that was contiguous with the Rayner Complex in the Neoproterozoic. This suggests that a major terrane-wide extensional event was associated with the disintegration of Rodinia. In the Neoproterozoic, the EGP-Rayner unit was therefore a tectonic entity distinct from cratonic India, with only the former being an integral component of Rodinia.Sandro Chatterjee, J. Amal Dev, Aishi Debnath, Anuj Ghosh, Soham Dey, Anik Mukherjee, Devsamridhi Arora, J.K. Tomson, Fernanda Guimarães, Naresh Chandra Pant, Saibal Gupt
Reply to Comments on Factors Associated With Hospitalization for Hypoglycemia and Hyperglycemia Among Older People in Long-Term Care Facilities
No full textLetter to the EditorYohanes A. Wondimkun, Gillian E. Caughey, Maria C. Inacio, Tracy Air, Catherine Lang, Michelle Hogan, Janet K. Slugget