Coupling hyperspectral imaging with machine learning algorithms for detecting polyethylene (PE) and polyamide (PA) in soils.

Soil, particularly in agricultural regions, has been recognized as one of the significant reservoirs for the emerging contaminant of MPs. Therefore, developing a rapid and efficient method is critical for their identification in soil. Here, we coupled HSI systems [i.e., VNIR (400-1000 nm), InGaAs (800-1600 nm), and MCT (1000-2500 nm)] with machine learning algorithms to distinguish soils spiked with white PE and PA (average size of 50 and 300 µm, respectively). The soil-normalized SWIR spectra unveiled significant spectral differences not only between control soil and pure MPs (i.e., PE 100% and PA 100%) but also among five soil-MPs mixtures (i.e., PE 1.6%, PE 6.9%, PA 5.0%, and PA 11.3%). This was primarily attributable to the 1st-3rd overtones and combination bands of C-H groups in MPs. Feature reductions visually demonstrated the separability of seven sample types by SWIR and the inseparability of five soil-MPs mixtures by VNIR. The detection models achieved higher accuracies using InGaAs (92-100%) and MCT (97-100%) compared to VNIR (44-87%), classifying 7 sample types. Our study indicated the feasibility of InGaAs and MCT HSI systems in detecting PE (as low as 1.6%) and PA (as low as 5.0%) in soil. SYNOPSIS: One of two SWIR HSI systems (i.e., InGaAs and MCT) with a sample imaging surface area of 3.6 mm² per grid cell was sufficient for detecting PE (as low as 1.6%) and PA (as low as 5.0%) in soils without the digestion and separation procedures.

Psychological impact of repeated epidemic exposure on healthcare workers: findings from an online survey of a healthcare workforce exposed to both SARS (severe acute respiratory syndrome) and COVID-19.

OBJECTIVE: To measure the psychological well-being of healthcare workers (HCWs) during this COVID-19 pandemic and examine the experiences of the subgroup of participants who were also HCWs during the 2003 SARS epidemic. DESIGN: Anonymous online survey adapted from a similar study conducted during the SARS epidemic, disseminated from July 2020 to August 2020. SETTING: Nine healthcare institutions across Singapore ranging from primary care, community care, tertiary care and specialised referral centres. PARTICIPANTS: Employees working in the participating healthcare institutions. RESULTS: Of 3828 survey returns, 3616 had at least one completed item on the questionnaire. Majority were female (74.7%), nurses (51.7%), foreign-born (53.2%) and not working in the tertiary care setting (52.1%). The median score on the Impact of Events Scale (IES) was 15 (IQR 23) and 28.2% of the sample scored in the moderate/severe range. 22.7% of the participants were also HCWs during SARS and more than half of them felt safer and better equipped in the current pandemic. 25.2% of SARS HCWs and 25.9% of non-SARS HCWs had moderate/severe IES scores (p=0.904). After adjusting for age, marital status, parity and length of work experience, racial minority groups and living apart from family were independent predictors of high IES regardless of prior SARS epidemic experience. Daily exposure to confirmed or suspect COVID-19 cases increased the odds of high IES for non-SARS HCWs only. CONCLUSIONS AND RELEVANCE: Overall, while 28% of HCWs in our study suffered from significant trauma-related psychological symptoms regardless of prior experience with the SARS epidemic, those with prior experience reported feeling safer and better equipped, finding the workload easier to manage, as well as having more confidence in their healthcare leaders. We recommend for more trauma-informed support strategies for our HCWs especially those from racial minority groups, who are foreign-born and isolated from their families.

Perceived Stress, Stigma, Traumatic Stress Levels and Coping Responses amongst Residents in Training across Multiple Specialties during COVID-19 Pandemic-A Longitudinal Study.

This study aimed to explore changes in psychological responses (perceived stress, traumatic stress, stigma, coping) over time in residents, as well as their predictors. The level of perceived stress, traumatic stress, stigma, and coping responses were assessed using the Perceived Stress Scale, Impact of Event-Revised, Healthcare Workers Stigma Scale, and Brief Coping Orientation to Problems Experienced (COPE) Inventory, respectively. We collected responses from 274 residents at baseline and 221 residents at 3 months follow-up (timepoint 2) from the National Healthcare Group (NHG) residency programs in Singapore. All residents reported lower perceived stress and lower perceived stigma compared to baseline. Use of avoidance coping was associated with all three psychological responses (perceived stress, traumatic stress, and stigma) across the two timepoints. Compared to baseline, specific factors associated with perceived stress and traumatic stress at timepoint 2 were living alone, less problem solving, and seeking social support. Residency programs should encourage active coping strategies (e.g., seeking social support, positive thinking, problem solving) among residents, and proactively identify residents who may be at higher risk of psychological sequelae due to circumstances that contribute to isolation.

Capecitabine pattern of usage, rate of febrile neutropaenia and treatment related death in asian cancer patients in clinical practice.

BACKGROUND: Oral capecitabine is increasingly replacing intravenous 5-fluorouracil in many chemotherapy regimens. However, data on the risk of febrile neutropaenia (FN) and treatment related death (TRD) with the drug remain sparse outside of clinical trial settings despite its widespread usage. This study aimed to determine these rates in a large cohort of patients treated in the University of Malaya Medical Centre (UMMC). MATERIALS AND METHODS: We reviewed the clinical notes of all patients prescribed with oral capecitabine chemotherapy for any tumour sites in University Malaya Medical Centre (UMMC) from 1st January 2009 till 31st June 2010. Information collected included patient demographics, histopathological features, treatment received including the different chemotherapy regimens and intent of treatment whether the chemotherapy was given for neoadjuvant, concurrent with radiation, adjuvant or palliative intent. The aim of this study is to establish the pattern of usage, FN and TRD rates with capecitabine in clinical practice outside of clinical trial setting. FN is defined as an oral temperature >38.5°or two consecutive readings of >38.0° for 2 hours and an absolute neutrophil count <0.5 x 109/L, or expected to fall below 0.5 x 109/L (de Naurois et al., 2010). Treatment related death was defined as death occurring during or within 30 days of last chemotherapy treatment. RESULTS: Between 1st January 2009 and 30th June 2010, 274 patients were treated with capecitabine chemotherapy in UMMC. The mean age was 58 years (range 22 to 82 years). Capecitabine was used in 14 different tumour sites with the colorectal site predominating with a total of 128 cases (46.7%), followed by breast cancer (35.8%). Capecitabine was most commonly used in the palliative setting accounting for 63.9% of the cases, followed by the adjuvant setting (19.7%). The most common regimen was single agent capecitabine with 129 cases (47.1%). The other common regimens were XELOX (21.5%) and ECX (10.2%). The main result of this study showed an overall FN rate of 2.2% (6/274). The overall TRD rate was 5.1% (14/274). The FN rate for the single agent capecitabine regimen was 1.6% (2/129) and the TRD rate was 5.4% (7/129). All the TRDs were with single agent capecitabine regimen were used for palliative intent. CONCLUSIONS: Oral capecitabine is used widely in clinical practice in a myriad of tumour sites and bears a low risk of febrile neutropaenia. However, capecitabine like any other intravenous chemotherapeutic agent carries a significant risk of treatment related death.

On-chip measurements of cell compressibility via acoustic radiation.

Measurements of mechanical properties of biological cells are of great importance because changes in these properties can be strongly associated with the progression of cell differentiation and cell diseases. Although state of the art methods, such as atomic force microscopy, optical tweezers and micropipette aspiration, have been widely used to measure the mechanical properties of biological cells, all these methods involve direct contact with the cell and the measurements could be affected by the contact or any local deformation. In addition, all these methods typically deduced the Young's modulus of the cells based on their measurements. Herein, we report a new method for fast and direct measurement of the compressibility or bulk modulus of various cell lines on a microchip. In this method, the whole cell is exposed to acoustic radiation force without any direct contact. The method exploits the formation of an acoustic standing wave within a straight microchannel. When the polystyrene beads and cells are introduced into the channel, the acoustic radiation force moves them to the acoustic pressure node and the movement speed is dependent on the compressibility. By fitting the experimental and theoretical trajectories of the beads and the cells, the compressibility of the cells can be obtained. We find that the compressibility of various cancer cells (MCF-7: 4.22 ± 0.19 × 10(-10) Pa(-1), HEPG2: 4.28 ± 0.12 × 10(-10) Pa(-1), HT-29: 4.04 ± 0.16 × 10(-10) Pa(-1)) is higher than that of normal breast cells (3.77 ± 0.09 × 10(-10) Pa(-1)) and fibroblast cells (3.78 ± 0.17 × 10(-10) Pa(-1)). This work demonstrates a novel acoustic-based method for on-chip measurements of cell compressibility, complementing existing methods for measuring the mechanical properties of biological cells.

Onset of psoriasis during therapy with fluoxetine.

OBJECTIVE: Psoriasis is a commonly diagnosed skin disorder that requires a long-term management and can have a profound impact on the quality of life of patients. Drugs that have been associated with the precipitation or exacerbation of psoriasis include lithium, beta-adrenergic receptor blocking agents and antimalarials. Despite extensive use of selective serotonin reuptake inhibitors (SSRIs) in clinical practice, there have been very few reports of selective serotonin reuptake inhibitor-related psoriasis. The main purpose of this study was to report fluoxetine-induced psoriasis in two Chinese women. RESULTS AND CONCLUSION: Although both patients had been taking fluoxetine for an extended period of time, the time scale of these two case studies suggests that fluoxetine played a causative role in these patients' psoriasis.