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Ambient mass spectrometry imaging (MSI) enables hundreds of analytes in tissue sections to be directly mapped at atmospheric pressure with minimal sample preparation. This field is currently experiencing rapid growth, with numerous reported ambient ionization techniques resulting in a "hundred flowers bloom" situation. Nanospray desorption electrospray ionization (nano-DESI), developed by the Laskin group in 2010, is a widely used liquid-extraction-based ambient ionization technique that was first used for mass spectrometry imaging of tissue in 2012. The nano-DESI probe comprises a primary capillary and a nanospray capillary, with the latter efficiently transferring analyte-containing droplets via a tiny liquid bridge formed between the probe and sample surface, thereby enabling nanoelectrospray ionization (nano-ESI) in front of the inlet of a mass spectrometer. The advantages of nano-DESI MSI include minimal sample preparation, high spatial resolution, and high sensitivity. These features are well-suited for imaging various sample types, including frozen tissue sections, microbial communities, and environmental samples. A PubMed-database search using the "nano-DESI" keyword revealed 72 related articles in the 2010-2024 period, with 34 of them published between 2021 and 2024, which indicates that nano-DESI has rapidly developed as an ambient ionization technique over recent years. Herein, we briefly introduce key nano-DESI-MSI research progress reported in the past three years with the aim of better understanding and facilitating the use of this technology. We first discuss advances in ion-source development. Since no commercial nano-DESI source exists, designing and constructing ion sources remain technical challenges that limit its development. Nano-DESI has been successfully coupled with various types of mass spectrometer, including LTQ Orbitrap, quadrupole-Orbitrap (Q Exactive), 6560 IM QTOF, timsTOF Pro2, triple quadrupole, and FTICR. These couplings have significantly expanded the applications range of the nano-DESI technique. Secondly, lipid analysis is a major nano-DESI-MSI applications area. While the complexities of lipid structures present great challenges for nano-DESI MSI, new nano-DESI coupling techniques have enabled the identification and imaging of fine lipid structures. Several novel imaging methods have recently been introduced to address difficulties associated with identifying lipid structures, such as distinguishing carbon-carbon double bonds (C=C) and sn -positional isomers. We finally highlight recent research progress in the nano-DESI MSI of intact protein assembles and proteoforms, which is a growing hotspot in the field. Unlike small lipid molecules, large protein molecules are very challenging to image and consequently demand higher instrumental performance (e.g., ionization efficiency, mass range, and sensitivity). In a similar manner to the ESI technique, nano-DESI tends to generate multiply charged molecular ions, which endows it with a significant advantage when imaging large protein molecules. Recent years have witnessed important nano-DESI-MSI progress for studying protein-ligand interactions and identifying and imaging endogenous proteoforms. In summary, this article focuses on nano-DESI research progress in terms of ion-source development, lipid-structure analysis, and spatial proteomics over the past three years and discusses key challenges that need to be addressed in the field.

Background: Migrant workers, a population of 170 million, often work in dangerous or unhealthy working environments and are likely to suffer workplace injuries and labour abuses. However, the risk of mortality in migrant workers compared with local workers is unknown. We aim to synthesise global evidence on migrant worker mortality risk and identify social determinants to inform health and safety protections for migrant workers., Methods: We conducted a systematic review and meta-analysis of peer-reviewed literature to examine mortality outcomes among migrant workers and associated risk factors. We searched MEDLINE, Embase, PsycINFO, and Ovid Global Health for studies published between Jan 1, 2000, and Jan 17, 2023, reporting quantitative primary research in English. A broad definition of migrant worker was used, including any worker who is foreign-born (ie, international first-generation migrant workers), either in paid employment or self-employment. Internal migrants, second-generation migrants, and foreign health-care workers were excluded. The primary outcome was any reported mortality, including all-cause mortality, cause-specific mortality, suicide, homicide, and fatal occupational injury. We used meta-analysis to compare outcomes between migrant worker and local worker populations, and a random-effects model to calculate pooled estimates. We used narrative synthesis to develop a data-driven conceptual framework capturing the intersectional social determinants of mortality in migrant workers. The study protocol is registered on PROSPERO, CRD42023372893., Findings: Of 11 495 identified records, 44 were included in the systematic review, of which 11 studies were pooled in meta-analyses. Data were from 16 countries, most of which were high-income countries, and included 44 338 migrant worker deaths, including migrants from the agriculture, construction, mining, and service industries. Compared with local workers, migrant workers had a higher risk of fatal occupational injury (pooled relative risk 1·71, 95% CI 1·22-2·38; eight studies; I 2 =99·4%), and a lower risk of all-cause mortality (0·94, 0·88-0·99; three studies, I 2 =90·7%). Migrant workers were more likely to die from external causes of death (such as falls or assaults) than internal causes of death (such as respiratory or digestive diseases) compared with local workers, with migrant workers also more likely to die from work-related homicides, especially in the retail and sex industries, with some evidence of higher suicide rates among female migrant workers compared with female local workers. Influential social determinants for poor fatality outcomes include migration-related factors (such as lower language proficiency, undocumented status, and long duration of stay) and labour-related factors (such as precarious employment, labour migration policies, and economic deregulation policies)., Interpretation: Migrant workers have a higher risk of workplace fatal injury despite being generally healthier than local workers, which could be explained by structural determinants such as precarious employment and inadequate safety protection. This health inequity must be urgently addressed through future interventions that account for migration-related and labour-related social determinants of health at the structural level, such as extending labour protection laws to migrant workers, and improving occupational health and safety and workplace conditions for this vital and growing workforce., Funding: UK Medical Research Council and National Institute for Health and Care Research., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Broadband supercontinuum (SC) light sources generated through nonlinear effects in solid-core photonic crystal fibers (PCFs) have been widely used in spectroscopy, metrology, and microscopy, leading to great application successes. The short-wavelength extension of such SC sources, a longstanding challenge, has been the subject of intensive study over the past two decades. However, the exact mechanism of blue and ultraviolet light generation, especially for some resonance spectral peaks in the short-wavelength regime, is not yet fully understood. Here, we demonstrate that the effect of inter-modal dispersive-wave radiation, which results from phase matching between pump pulses at the fundamental optical mode and packets of linear waves at some higher-order modes (HOMs) propagating in the PCF core, might be one of the critical mechanisms that can result in some resonance spectral components with wavelengths much shorter than that of the pump light. We observed in an experiment that several spectral peaks resided in the blue and ultraviolet regimes of the SC spectrum, whose central wavelengths can be tuned by varying the PCF-core diameter. These experimental results can be interpreted well using the inter-modal phase-matching theory, providing some useful insights into the SC generation process.

The earthquake early warning (EEW)-research group at National Taiwan University has been developing a microelectromechanical system-based accelerometer called “P-Alert”, designed for issuing EEWs. The main advantage of P-Alert is that it is a relatively economical seismometer. However, because of the expensive nature of commercial hardware for structural health monitoring (SHM) systems, the application of SHM to buildings remains limited. To determine the performance of P-Alert for evaluating post-earthquake building safety, we conducted a series of steel-frame shaking table tests with incremental damage. We used the fragility curves of different damage levels and the interstory drift ratios (calculated by the measured acceleration of each story using double integration and a filter) to gauge the potential damage levels. We concluded that the acceptable detection of damage for an entire building is possible. With improvements to the synchronization of the P-Alert sensors, we also anticipate a damage localization feature for the stories of a building.

Coptotermes suzhouensis (Isoptera: Rhinotermitidae) is a significant subterranean termite pest of wooden structures and is widely distributed in southeastern China. The complete mitochondrial DNA sequence of C. suzhouensis was analyzed in this study. The mitogenome was a circular molecule of 15,764 bp in length, which contained 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an A+T-rich region with a gene arrangement typical of Isoptera mitogenomes. All PCGs were initiated by ATN codons and terminated by complete termination codons (TAA), except COX2, ND5, and Cytb, which ended with an incomplete termination codon T. All tRNAs displayed a typical clover-leaf structure, except for tRNASer(AGN), which did not contain the stem-loop structure in the DHU arm. The A+T content (69.23%) of the A+T-rich region (949 bp) was higher than that of the entire mitogenome (65.60%), and two different sets of repeat units (A+B) were distributed in this region. Comparison of complete mitogenome sequences with those of Coptotermes formosanus indicated that the two taxa have very high genetic similarity. Forty-one representative termite species were used to construct phylogenetic trees by maximum likelihood, maximum parsimony, and Bayesian inference methods. The phylogenetic analyses also strongly supported (BPP, MLBP, and MPBP = 100%) that all C. suzhouensis and C. formosanus samples gathered into one clade with genetic distances between 0.000 and 0.002. This study provides molecular evidence for a more robust phylogenetic position of C. suzhouensis and inferrs that C. suzhouensis was the synonymy of C. formosanus.

Purpose: To compare the outcomes of sub-Bowman keratomileusis (100-μm flap) and laser in situ keratomileusis (LASIK) (120-μm flap) using 150-kHz femtosecond laser., Design: Randomized, double-masked, contralateral clinical trial., Methods: One hundred patients (200 eyes) with myopia or myopic astigmatism were included. Postoperative examinations were performed at week 1 and months 1, 3, 6, and 12. Main outcome measures included postoperative uncorrected (UCVA) and best-corrected distance visual acuity (BCVA); manifest refraction spherical equivalent; efficacy and safety indices; corneal thickness; and complications., Results: The mean age of patients was 33.9 ± 7.9 years. Overall, the preoperative UCVA, BCVA, and manifest refraction spherical equivalent were 1.349 ± 0.332, -0.022 ± 0.033, and -5.81 ± 1.61 diopters, respectively. No significant difference was observed in preoperative (P ≥ .226) or intraoperative parameters (P ≥ .452) between both groups, except residual stromal thickness (P < .001). The UCVA, manifest refraction spherical equivalent, and central corneal thickness stabilized by 1 week, while the thinnest corneal thickness stabilized by 3 months postoperatively. There was no significant difference between both groups for any parameter during all follow-up visits (P ≥ .132) except the 3-month safety index, which was better in the sub-Bowman keratomileusis group (P = .007). Soft opaque bubble layer was noted intraoperatively in 12 cases (7, 100-μm group; 5, 120-μm group; P = .577). No postoperative complications were observed., Conclusions: Our study did not find any differences in the visual and refractive outcomes between femtosecond-assisted sub-Bowman keratomileusis and LASIK. Both surgeries resulted in quick visual recovery as early as 1 week postoperatively., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Eu(PPA)3 dioxane and Tb(PPA)3 dioxane were synthesized by firstly adopting dioxane as second ligand and using pipemidic acid (PPA) as first ligand. In contrast with two kinds of binary lanthanide complexes Eu(PPA)3 and Tb(PPA)3, the photoluminescent intensities of Eu (PPA)3 dioxane and Tb (PPA)3 dioxane are much stronger, especially for that of Tb(PPA)3 dioxane. The enhancement of photoluminescent intensities of Eu(PPA)3 dioxane and Tb(PPA)3 dioxane is because of the replacement of dioxane for water bonded to Eu3+ and Tb3+, by which the energy loss through heat oscillation will be inhibited. The as-synthesized lanthanide complexes were characterized by FT-IR, photoluminescence spectra and photoluminescence lifetime. The lifetime of Eu(PPA)3 dioxane and Tb(PPA) dioxane remarkably changed compared with those of Eu(PPA)3 and Tb(PPA)3. However, there is much difference for the lifetime change of as-synthesized lanthanide complexes formed by Eu3+ and Tb3+, which shows that there is different energy transfer process for the lanthanide complexes formed by Eu3+ and Tb3+. The synthesis of lanthanide complexes using dioxane as second ligand will provide a new method to detect the existence of dioxane.