Matrix-assisted laser desorption/ionisation-imaging mass spectrometry (MALDI-IMS) is now an established imaging modality with particular utility in the study of biological, biomedical and pathological processes. In the first instance, the use of stable isotopically labelled (SIL) compounds in MALDI-IMS has addressed technical barriers to increase the accuracy and versatility of this technique. This has undoubtedly enhanced our ability to interpret the two-dimensional ion intensity distributions produced from biological tissue sections. Furthermore, studies using delivery of SIL compounds to live tissues have begun to decipher cell, tissue and inter-tissue metabolism while maintaining spatial resolution. Here, we review both the technical and biological applications of SIL compounds in MALDI-IMS, before using the uptake and metabolism of glucose in bovine ocular lens tissue to illustrate the current limitations of SIL compound use in MALDI-IMS. Finally, we highlight recent instrumentation advances that may further enhance our ability to use SIL compounds in MALDI-IMS to understand biological and pathological processes.

We aimed to determine whether additional molecular and microbiological evaluations of methicillin-resistant Staphylococcus aureus (MRSA) isolated from patients newly identified as nasal carriers were useful for control strategies and whether longitudinal testing during the same or repeat hospitalization changed MRSA status. Nasal swabs from patients positive by Xpert MRSA PCR and not known to be colonized in the previous year were cultured for S. aureus. Isolates were tested for resistance to a variety of antibiotics, including high-level mupirocin resistance (HLMR) and low-level mupirocin resistance (LLMR) and the presence of genes mecA and mupA and those for Panton-Valentine leukocidin (PVL), USA300, and USA400. Repeat nasal screens during the 6-month study were tested for continued presence of MRSA. Among 130 patients, cultures revealed MRSA in 85 (65.4%), methicillin-susceptible S. aureus in 19 (14.6%), and no growth in 26 (20%). MRSA isolates were USA300 positive in 13/85 (15.3%) and LLMR in 8/85 (9.4%) patients. No isolates were HLMR or mupA positive. mecA dropout was detected in 9/130 (6.9%) patients. The rate of subsequent MRSA infections in USA300-positive versus -negative patients was not different. MRSA nasal status remained concordant in 69/70 (98.6%) patients who had follow-up testing. The findings do not support expanding MRSA surveillance to include routine detection of genes for USA300, PVL, or mupA, all of which were either of low frequency or not significantly associated with MRSA infection risk in our population of newly identified nasal carriers. Repeat nasal screening for MRSA during the same or subsequent hospitalizations over 6 months could also be deferred, reducing costs associated with screening.

The structural determination of natural products (NPs) can be arduous due to sample heterogeneity. This often demands itera-tive purification processes and characterization of complex molecules that may only be available in miniscule quantities. Microcrystal electron diffraction (microED) has recently shown promise as a method to solve crystal structures of NPs from nanogram quantities of analyte. However, its implementation in NP discovery remains hampered by sample throughput and purity requirements akin to traditional NP-discovery workflows. In the methods described herein, we leverage the resolving power of transmission electron microscopy (TEM) and the miniaturization capabilities of DNA microarray technology to address these challenges through the establishment of an NP screening platform, array electron diffraction (ArrayED). In this workflow, an array of HPLC fractions taken from crude extracts are deposited onto TEM grids in picoliter-sized droplets. This multiplexing of analytes on TEM grids enables 1200 or more unique samples to be simultaneously inserted into a TEM equipped with an autoloader. Selected area electron diffraction analysis of these microarrayed grids allows for rapid identification of crystalline metabolites. In this study, ArrayED enabled structural characterization of 14 natural products, including four novel crystal structures and two novel polymorphs, from 20 crude extracts. Moreover, we identify several chemical species that would not be detected by standard mass spectrometry (MS) or UV/Vis and crystal forms that would not be characterized using traditional methods.

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This research explores the employability of Chinese international graduates in the Australian labor market. It captures the significance of six forms of capital (i.e., human, social, cultural, psychological, identity, and agentic) to Chinese international graduates when they develop their careers in Australia. The research employed Bourdieu’s theory of practice and a capitals-based approach as the theoretical framework. Data were collected via an online survey (N=203) and in-depth interviews (N=14). The findings reveal that in addition to getting employments in Australia, the graduates also benefited from developing and utilizing these six capitals in terms of sustainable employments, professional growth, and well-being. As such, this research argued for a broad definition of employability which include different capitals as the inputs and different aspects of employability outcomes as the outputs, namely, employment outcomes, sustainable employments, professional growth, and well-being. The findings also implied that various stakeholders should share responsibilities to support international students in building multiple capitals.

Wellbeing has been argued as an important aspect of employability; however, little has been known about the wellbeing of international graduates in the host labor market. This study aimed to explore the association between employability capitals and wellbeing of Chinese international graduates when they develop their careers in the Australian labor market. A capitals-based approach to employability and the PERMA model of wellbeing were applied as the conceptual framework. This chapter deployed a qualitative approach to explore how different capitals (e.g., human, social, cultural, psychological, identity, and agentic capitals) influenced the graduates' wellbeing in the Australian labor market. Fourteen Chinese international graduates participated in in-depth interviews. The findings revealed that the six capitals influenced the participants' wellbeing differently in terms of PERMA; the contributions of several capitals to the participants' wellbeing depended on the fields, and both subjective wellbeing and accomplishment were highly individualized.

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