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Time-domain reconstruction using sensitivity coefficients for limited view ultrawide band tomography

Abdullah MZ, Yin W, Bilal M, Armitage DW, Mackin R, Peyton AJ

Rev Sci Instrum, 2007 Aug;78(8):084703.
PMID: 17764343

This article addresses time-domain ultrawide band (UWB) electromagnetic tomography for reconstructing the unknown spatial characteristic of an object from observations of the arrivals of short electromagnetic (EM) pulses. Here, the determination of the first peak arrival of the EM traces constitutes the forward problem, and the inverse problem aims to reconstruct the EM property distribution of the media. In this article, the finite-difference time-domain method implementing a perfectly matched layer is used to solve the forward problem from which the system sensitivity maps are determined. Image reconstruction is based on the combination of a linearized update and regularized Landweber minimization algorithm. Experimental data from a laboratory UWB system using targets of different contrasts, sizes, and shapes in an aqueous media are presented. The results show that this technique can accurately detect and locate unknown targets in spite of the presence of significant levels of noise in the data.
Fulltext From starvation to depression: unveiling the link between the great famine and late-life depression

Guo L, Sang B, Li S, Xia Z, Li M, Yang M, et al.

BMC Public Health, 2024 Nov 08;24(1):3096.
PMID: 39516771 DOI: 10.1186/s12889-024-20604-8

BACKGROUND: The Great Famine in China from 1959 to 1961 is recognized as one of the most severe social and public health disasters of the 20th century, with profound long-term impacts on the health of survivors, particularly on their mental health. Early-life malnutrition and psychological trauma are considered to contribute to a range of health issues in adulthood, including depression.
OBJECTIVE: This study aims to explore how the experience of the Chinese Great Famine from 1959 to 1961 affects the risk of depressive symptoms among the elderly. Using a mechanism analysis, the study investigates the roles of social support, socioeconomic status, and intergenerational support in this process.
METHODS: Using micro-level individual data from the China Health and Retirement Longitudinal Survey (CHARLS), combined with province-level excess mortality data, this study employs a cohort-based difference-in-differences model to identify the causal effects of the famine experience on depression levels among the elderly.
RESULTS: The study reveals that experiencing the Great Famine significantly increases the risk of depression among the elderly. This effect is more pronounced among rural residents, those who experienced the famine during adolescence, and in regions less influenced by Confucian culture. The mechanism analysis indicates that diminished social support, lower socioeconomic status, and insufficient intergenerational support are the primary pathways through which the famine experience influences depression levels in the elderly.
CONCLUSIONS: The experience of the Great Famine has exerted a long-term and profound impact on the mental health of the elderly in China, particularly in terms of depression. The findings provide new perspectives on understanding the long-term effects of major historical events on health and offer important empirical evidence for the development of mental health intervention policies for the elderly.
Easing caregiver strain: The power of health check-ups

Guo L, Sang B, Zhang L, Yin W, Yuan X, Ma C

Soc Sci Med, 2024 Dec;362:117445.
PMID: 39481276 DOI: 10.1016/j.socscimed.2024.117445

Against the backdrop of global aging and escalating pressures on family caregiving, this study delves into the impact of health check-ups for the elderly on alleviating the objective burden of family caregiving by analyzing China's Free Health Check-up Program (FHCP). Using an unbalanced panel dataset spanning 2011, 2013, 2015, 2018, and 2020, comprising approximately 35,000 observations of the elderly population aged 65 and above, the research employs the Difference-in-Differences method. The research reveals a significant 9.18% reduction in family caregiving time following the implementation of FHCP, primarily attributed to the enhancement of the elderly's self-care abilities and health awareness. This study elucidates, for the first time, the efficacy and mechanisms of health check-ups in alleviating caregiving objective burdens, providing evidence for the formulation of pertinent policies. It underscores the significance of routine health check-ups as a public health intervention in supporting family caregivers and addressing the challenges of aging.
Fulltext Novel Plasmid-Mediated Colistin Resistance Gene mcr-3 in Escherichia coli

Yin W, Li H, Shen Y, Liu Z, Wang S, Shen Z, et al.

mBio, 2017 06 27;8(3).
PMID: 28655818 DOI: 10.1128/mBio.00543-17

The mobile colistin resistance gene mcr-1 has attracted global attention, as it heralds the breach of polymyxins, one of the last-resort antibiotics for the treatment of severe clinical infections caused by multidrug-resistant Gram-negative bacteria. To date, six slightly different variants of mcr-1, and a second mobile colistin resistance gene, mcr-2, have been reported or annotated in the GenBank database. Here, we characterized a third mobile colistin resistance gene, mcr-3 The gene coexisted with 18 additional resistance determinants in the 261-kb IncHI2-type plasmid pWJ1 from porcine Escherichia colimcr-3 showed 45.0% and 47.0% nucleotide sequence identity to mcr-1 and mcr-2, respectively, while the deduced amino acid sequence of MCR-3 showed 99.8 to 100% and 75.6 to 94.8% identity to phosphoethanolamine transferases found in other Enterobacteriaceae species and in 10 Aeromonas species, respectively. pWJ1 was mobilized to an E. coli recipient by conjugation and contained a plasmid backbone similar to those of other mcr-1-carrying plasmids, such as pHNSHP45-2 from the original mcr-1-harboring E. coli strain. Moreover, a truncated transposon element, TnAs2, which was characterized only in Aeromonas salmonicida, was located upstream of mcr-3 in pWJ1. This ΔTnAs2-mcr-3 element was also identified in a shotgun genome sequence of a porcine E. coli isolate from Malaysia, a human Klebsiella pneumoniae isolate from Thailand, and a human Salmonella enterica serovar Typhimurium isolate from the United States. These results suggest the likelihood of a wide dissemination of the novel mobile colistin resistance gene mcr-3 among Enterobacteriaceae and aeromonads; the latter may act as a potential reservoir for mcr-3IMPORTANCE The emergence of the plasmid-mediated colistin resistance gene mcr-1 has attracted substantial attention worldwide. Here, we examined a colistin-resistant Escherichia coli isolate that was negative for both mcr-1 and mcr-2 and discovered a novel mobile colistin resistance gene, mcr-3 The amino acid sequence of MCR-3 aligned closely with phosphoethanolamine transferases from Enterobacteriaceae and Aeromonas species originating from both clinical infections and environmental samples collected in 12 countries on four continents. Due to the ubiquitous profile of aeromonads in the environment and the potential transfer of mcr-3 between Enterobacteriaceae and Aeromonas species, the wide spread of mcr-3 may be largely underestimated. As colistin has been and still is widely used in veterinary medicine and used at increasing frequencies in human medicine, the continuous monitoring of mobile colistin resistance determinants in colistin-resistant Gram-negative bacteria is imperative for understanding and tackling the dissemination of mcr genes in both the agricultural and health care sectors.
Preparation of robust, water-resistant, antibacterial, and antioxidant chitosan-based films by incorporation of cinnamaldehyde-tannin acid-zinc acetate nanoparticles

Yin W, Yan R, Zhou X, Li X, Sang S, Julian McClements D, et al.

Food Chem, 2023 Mar 24;419:136004.
PMID: 37054511 DOI: 10.1016/j.foodchem.2023.136004

Chitosan (CS) films have poor mechanical property, low water-resistance and limited antimicrobial activity, which hinder their application in food preservation industry. Cinnamaldehyde-tannic acid-zinc acetate nanoparticles (CTZA NPs) assembled from edible medicinal plant extracts were successfully incorporated into CS films to solve these issues. The tensile strength and water contact angle of the composite films increased about 5.25-fold and 17.55°. The addition of CTZA NPs reduced the water sensitivity of CS films, which could undergo appreciable stretching in water without breaking. Furthermore, CTZA NPs significantly enhanced the UV adsorption, antibacterial, and antioxidant properties of the films, while reduced their water vapor permeability. Moreover, it was possible to print inks onto the films because the presence of the hydrophobic CTZA NPs facilitated the deposition of carbon powder onto their surfaces. The films with great antibacterial and antioxidant activities can be applied for food packaging application.
Fulltext Asia Pacific TAVI registry (an APSIC initiative): initial report of early outcomes: Asia Pacific TAVI registry

Tay E, Khaing T, Yin W, Posas E, Kao P, Buddhari W, et al.

AsiaIntervention, 2021 Jul;7(1):54-59.
PMID: 34913003 DOI: 10.4244/AIJ-D-18-00053

Aims: The aim of the study was to report the clinical experience, 30-day mortality and acute outcomes of patients undergoing transcatheter aortic valve implantation (TAVI) in the Asia Pacific region.
Methods and results: The Asia Pacific TAVI registry is an international, multicentre, prospective, observational registry managed under the auspices of the Asian Pacific Society of Interventional Cardiology (APSIC). Patients undergoing TAVI in seven centres from Hong Kong, Japan, Philippines, Singapore and Taiwan, treated with TAVI devices for severe symptomatic aortic stenosis, were assessed. This first review presents the acute results and 30-day mortality. A multivariable analysis was also performed to identify independent predictors of early all-cause mortality. The enrolment was from 2009 to 2017 and a total of 1,125 patients were recruited. The 30-day mortality rate was 2.5%. Baseline logistic EuroSCORE more than 16 was independently associated with a 2.8-times increased risk of 30-day all-cause mortality (p=0.016). Post-procedural stroke (HR 4.9, p=0.008) was also associated with increased mortality.
Conclusions: This initial report of the Asia Pacific TAVI registry demonstrated good acute success and low 30-day mortality. The preprocedural logistic EuroSCORE and post-procedural stroke incidence were strongly associated with acute mortality. Further attempts to reduce post-procedural stroke should be explored.