25 research outputs found

    Using Magnetically Responsive Tea Waste to Remove Lead in Waters under Environmentally Relevant Conditions

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    We report the use of a simple yet highly effective magnetite-waste tea composite to remove lead(II) (Pb[superscript 2+]) ions from water. Magnetite-waste tea composites were dispersed in four different types of water–deionized (DI), artificial rainwater, artificial groundwater and artificial freshwater–that mimic actual environmental conditions. The water samples had varying initial concentrations (0.16–5.55 ppm) of Pb[superscript 2+] ions and were mixed with the magnetite-waste tea composite for at least 24 hours to allow adsorption of the Pb[superscript 2+] ions to reach equilibrium. The magnetite-waste tea composites were stable in all the water samples for at least 3 months and could be easily removed from the aqueous media via the use of permanent magnets. We detected no significant leaching of iron (Fe) ions into the water from the magnetite-waste tea composites. The percentage of Pb adsorbed onto the magnetite-waste tea composite ranged from ~70% to 100%; the composites were as effective as activated carbon (AC) in removing the Pb[superscript 2+] ions from water, depending on the initial Pb concentration. Our prepared magnetite-waste tea composites show promise as a green, inexpensive and highly effective sorbent for removal of Pb in water under environmentally realistic conditions.SUTD-MIT International Design Center (Research Grant IDG11200105/IDD11200109)Singapore-MIT Allianc

    Chronic ringworm infestation and Marjolin’s ulcer, an association unknown in the literature

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    We report here a case of Marjolin’s ulcer developing in a long-standing, inadequately treated, chronic ringworm infestation of the lower limb. A 35-year-old female patient with a ten-year history of a chronic ringworm infestation had developed a nonhealing ulcer in an area of infestation on the right leg. A biopsy revealed well-differentiated squamous cell carcinoma associated with the ringworm infection. A below-knee amputation by an inguinal block dissection was performed. We conclude that proper and timely treatment of fungal infections of the skin is needed to allow for healing of dermal infections and thus the prevention of the disastrous consequences that recurrent mechanical trauma from scratching of the affected area, leading to occult malignancy, which may occur in a small number of patients

    Antenatal risk factors for postnatal depression: a prospective study of chinese women at maternal and child health centres

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    Background: Risk factors for postnatal depression (PND) are under-explored in the Chinese populations. There is increasing recognition of the importance of identifying predictive factors during the antenatal period for PND. The present study aimed to identify the risk factors for postnatal depression in a community cohort of Chinese women with special focus on the antenatal risk factors.Methods: Eight hundred and five Chinese women were interviewed during their third trimester of pregnancy and at around 2 months postnatally. Putative risk factors for PND were collected and the diagnosis of PND was confirmed by the Structured Clinical Interview for DSM-IV Axis I Disorders. The 2-month postnatal depression status was used as the dependent variable for univariate and multivariate analyses against putative risk factors.Results: Marital dissatisfaction (Relative Risk = 8.27), dissatisfied relationship with mother-in-law (Relative Risk = 3.93), antenatal depressive symptomatology (Relative Risk = 3.90), and anxiety-prone personality (Relative Risk = 2.14) predicted PND in Chinese women independently.Conclusions: Chinese women tend to keep their own feelings and emotions and it is important to monitor Chinese pregnant women with these predictive risk factors so that PND can be identified early. © 2012 Siu et al; licensee BioMed Central Ltd.published_or_final_versio

    The utility of screening for perinatal depression in the second trimester among Chinese: a three-wave prospective longitudinal study

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    This paper aims to study the pattern of perinatal depressive symptomatology and determine the predictive power of second trimester perinatal depressive symptoms for future perinatal periods. A population-based sample of 2,178 women completed the Edinburgh Postnatal Depression Scale (EPDS) in the second and third trimesters and at 6 weeks postpartum. Repeated measures ANOVAs were used to determine the EPDS scores across three stages. The predictive power of the second trimester EPDS score in identifying women with an elevated EPDS score in the third trimester and at 6 weeks postpartum were determined. The predictive power of the second trimester EPDS score was further assessed using stepwise logistic regression and receiver operator characteristic curves. EPDS scores differed significantly across three stages. The rates were 9.9%, 7.8%, and 8.7% for an EPDS score of >14 in the second and third trimesters and at 6 weeks postpartum, respectively. Using a cut-off of 14/15, the second trimester EPDS score accurately classified 89.6% of women in the third trimester and 87.2% of those at 6 weeks postpartum with or without perinatal depressive symptomatology. Women with a second trimester EPDS score >14 were 11.78 times more likely in the third trimester and 7.15 times more likely at 6 weeks postpartum to exhibit perinatal depressive symptomatology after adjustment of sociodemographic variables. The area under the curve for perinatal depressive symptomatology was 0.85 in the third trimester and 0.77 at 6 weeks postpartum. To identify women at high risk for postpartum depression, healthcare professionals could consider screening all pregnant women in the second trimester so that secondary preventive intervention may be implemented

    The Efficiency of the Human CD8+ T Cell Response: How Should We Quantify It, What Determines It, and Does It Matter?

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    Multidisciplinary techniques, in particular the combination of theoretical and experimental immunology, can address questions about human immunity that cannot be answered by other means. From the turnover of virus-infected cells in vivo, to rates of thymic production and HLA class I epitope prediction, theoretical techniques provide a unique insight to supplement experimental approaches. Here we present our opinion, with examples, of some of the ways in which mathematics has contributed in our field of interest: the efficiency of the human CD8+ T cell response to persistent viruses

    Differential and shared genetic effects on kidney function between diabetic and non-diabetic individuals

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    A large-scale GWAS provides insight on diabetes-dependent genetic effects on the glomerular filtration rate, a common metric to monitor kidney health in disease.Reduced glomerular filtration rate (GFR) can progress to kidney failure. Risk factors include genetics and diabetes mellitus (DM), but little is known about their interaction. We conducted genome-wide association meta-analyses for estimated GFR based on serum creatinine (eGFR), separately for individuals with or without DM (nDM = 178,691, nnoDM = 1,296,113). Our genome-wide searches identified (i) seven eGFR loci with significant DM/noDM-difference, (ii) four additional novel loci with suggestive difference and (iii) 28 further novel loci (including CUBN) by allowing for potential difference. GWAS on eGFR among DM individuals identified 2 known and 27 potentially responsible loci for diabetic kidney disease. Gene prioritization highlighted 18 genes that may inform reno-protective drug development. We highlight the existence of DM-only and noDM-only effects, which can inform about the target group, if respective genes are advanced as drug targets. Largely shared effects suggest that most drug interventions to alter eGFR should be effective in DM and noDM.</p

    Extraordinary Transmission Characteristics of Subwavelength Nanoholes with Rectangular Lattice

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    We investigate the extraordinary optical transmission (EOT) properties of nanohole arrays with a rectangular lattice for label-free refractive index sensing applications. We show that the deviation within the periodicities along the two axes at the nanohole plane leads to more advantageous spectral quality of EOT signal compared to the conventional square lattice geometries. We introduce a way to further improve the sensitivity of the aperture system by carefully choosing the periodicities. We introduce nanohole arrays with a rectangular lattice supporting EOT signals with larger figure-of-merit values as well as enabling much stronger light transmission. We also model a nanohole system covered with a thin dielectric layer, mimicking biomolecules captured on the gold surface, in order to show its biosensing capability. We also show that certain deviation amounts between periodicities create spectral splitting within the EOT signal leading to larger spectral shifts in the presence of a thin dielectric film. Keywords: Plasmonics, Nanoholes, Extraordinary optical transmission, Rectangular lattice, Label-free biosensin
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