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Uptake and speciation of zinc in edible plants grown in smelter contaminated soils
Heavy metal accumulation in edible plants grown in contaminated soils poses a major environmental risk to humans and grazing animals. This study focused on the concentration and speciation of Zn in different edible plants grown in soils contaminated with smelter wastes (Spelter, WV, USA) containing high levels of the metals Zn, Cu, Pb, Cd. Their accumulation was examined in different parts (roots, stem, and leaves) of plants and as a function of growth stage (dry seed, sprouting seed, cotyledon, and leaves) in the root vegetables radish, the leafy vegetable spinach and the legume clover. Although the accumulation of metals varied significantly with plant species, the average metal concentrations were [Zn] > [Pb] > [Cu] > [Cd]. Metal uptake studies were complemented with bulk and micro X-ray absorption spectroscopy (XAS) at Zn K-edge and micro X-ray fluorescence (μXRF) measurements to evaluate the speciation and distribution of Zn in these plant species. Dynamic interplay between the histidine and malate complexation of Zn was observed in all plant species. XRF mapping of spinach leaves at micron spatial resolution demonstrated the accumulation of Zn in vacuoles and leaf tips. Radish root showed accumulation of Zn in root hairs, likely as ZnS nanoparticles. At locations of high Zn concentration in spinach leaves, μXANES suggests Zn complexation with histidine, as opposed to malate in the bulk leaf. These findings shed new light on the dynamic nature of Zn speciation in plants
Research on nonlinear and quantum optics at the photonics and quantum information group of the University of Valladolid
We outline the main research lines in Nonlinear and Quantum Optics of the Group of Photonics and Quantum Information at the University of Valladolid. These works focus on Optical Solitons, Quantum Information using Photonic Technologies and the development of new materials for Nonlinar Optics. The investigations on optical solitons cover both temporal solitons in dispersion managed fiber links and nonparaxial spatial solitons as described by the Nonlinear Helmholtz Equation. Within the Quantum Information research lines of the group, the studies address new photonic schemes for quantum computation and the multiplexing of quantum data. The investigations of the group are, to a large extent, based on intensive and parallel computations. Some associated numerical techniques for the development of the activities described are briefly sketched
HIV prevalence and undiagnosed infection among a community sample of gay and bisexual men in Scotland, 2005-2011: implications for HIV testing policy and prevention
<b>Objective</b><p></p>
To examine HIV prevalence, HIV testing behaviour, undiagnosed infection and risk factors for HIV positivity among a community sample of gay men in Scotland.<p></p>
<b>Methods</b><p></p>
Cross-sectional survey of gay and bisexual men attending commercial gay venues in Glasgow and Edinburgh, Scotland with voluntary anonymous HIV testing of oral fluid samples in 2011. A response rate of 65.2% was achieved (1515 participants).<p></p>
<b>Results</b><p></p>
HIV prevalence (4.8%, 95% confidence interval, CI 3.8% to 6.2%) remained stable compared to previous survey years (2005 and 2008) and the proportion of undiagnosed infection among HIV-positive men (25.4%) remained similar to that recorded in 2008. Half of the participants who provided an oral fluid sample stated that they had had an HIV test in the previous 12 months; this proportion is significantly higher when compared to previous study years (50.7% versus 33.8% in 2005, p<0.001). Older age (>25 years) was associated with HIV positivity (1.8% in those <25 versus 6.4% in older ages group) as was a sexually transmitted infection (STI) diagnosis within the previous 12 months (adjusted odds ratio 2.13, 95% CI 1.09–4.14). There was no significant association between age and having an STI or age and any of the sexual behaviours recorded.<p></p>
<b>Conclusion</b><p></p>
HIV transmission continues to occur among gay and bisexual men in Scotland. Despite evidence of recent testing within the previous six months, suggesting a willingness to test, the current opt-out policy may have reached its limit with regards to maximising HIV test uptake. Novel strategies are required to improve regular testing opportunities and more frequent testing as there are implications for the use of other biomedical HIV interventions.<p></p>
Long-lived charged Higgs at LHC as a probe of scalar Dark Matter
We study inert charged Higgs boson production and decays at LHC
experiments in the context of constrained scalar dark matter model (CSDMM). In
the CSDMM the inert doublet and singlet scalar's mass spectrum is predicted
from the GUT scale initial conditions via RGE evolution. We compute the cross
sections of processes at the LHC and show that
for light the first one is dominated by top quark mediated 1-loop
diagram with Higgs boson in s-channel. In a significant fraction of the
parameter space are long-lived because their decays to predominantly
singlet scalar dark matter (DM) and next-to-lightest (NL) scalar, are suppressed by the small singlet-doublet mixing
angle and by the moderate mass difference
The experimentally measurable displaced vertex in decays to leptons
and/or jets and missing energy allows one to discover the signal over
the huge background. We propose benchmark points for studies of this
scenario at the LHC. If, however, are short-lived, the subsequent
decays necessarily produce additional
displaced vertices that allow to reconstruct the full decay chain.Comment: 15 pages, 5 figure
Optimization of Sound Pulse Generation for Photoacoustic Sensing Applications
Photoacoustically generated sound pulses are currently used in various NDT, NDE and sensing applications, often because this method generates ultrasound without touching the sample. The generation mechanisms are relatively well known, including directional patterns, sound pressures and damage thresholds for the laser intensity. Our study addresses the optimal conditions for sound generation for sensing purposes in a liquid using a low power diode pumped Nd:YAG pulse laser.</p
Strategies for implementing placental transfusion at birth: a systematic review
Background: Enhanced placental transfusion reduces adverse neonatal outcomes, including death. Despite being endorsed by the World Health Organization in 2012, the method has not been adopted widely in practice.
Methods: We performed a systematic literature search and included quality improvement projects on placental transfusion at birth and studies on barriers to implementation. We extracted information on population, methods of implementation, obstacles to implementation, and strategies to overcome them.
Results: We screened 99 studies out of which 18 were included in the review. The preferred methods of implementation were protocol development (86% of studies) reinforced by targeted education (64% of studies) and multidisciplinary team involvement (43% of studies). Barriers to implementation were mentioned in 12 studies and divided into four categories: general factors such as lack of staff awareness (5 studies) and professional resistance to change (5 studies); obstetrician‐specific concerns, including the impact during cesarean (3 studies) and the risk of postpartum hemorrhage (3 studies); pediatrician‐specific concerns, including the need for resuscitation (5 studies), risk of jaundice (3 studies), and polycythemia (2 studies); and logistical difficulties. The main strategies to facilitate placental transfusion at birth included effective multidisciplinary team collaboration, protocol development, targeted education, and constructive feedback sessions.
Conclusions: Placental transfusion implementation requires a multidisciplinary approach, with obstetricians, midwives, nurses, and pediatricians central to adoption of the practice. Understanding the obstacles to implementation informs strategies to increase placental transfusion adoption of practice worldwide. We suggest a stepwise approach to implementation and enhancement of placental transfusion into practice
Comparison of contact patterns relevant for transmission of respiratory pathogens in Thailand and the Netherlands using respondent-driven sampling
Understanding infection dynamics of respiratory diseases requires the identification and quantification of behavioural, social and environmental factors that permit the transmission of these infections between humans. Little empirical information is available about contact patterns within real-world social networks, let alone on differences in these contact networks between populations that differ considerably on a socio-cultural level. Here we compared contact network data that were collected in the Netherlands and Thailand using a similar online respondent-driven method. By asking participants to recruit contact persons we studied network links relevant for the transmission of respiratory infections. We studied correlations between recruiter and recruited contacts to investigate mixing patterns in the observed social network components. In both countries, mixing patterns were assortative by demographic variables and random by total numbers of contacts. However, in Thailand participants reported overall more contacts which resulted in higher effective contact rates. Our findings provide new insights on numbers of contacts and mixing patterns in two different populations. These data could be used to improve parameterisation of mathematical models used to design control strategies. Although the spread of infections through populations depends on more factors, found similarities suggest that spread may be similar in the Netherlands and Thailand
An inflammation-based prognostic score (mGPS) predicts cancer survival independent of tumour site: a Glasgow Inflammation Outcome Study
INTRODUCTION: A selective combination of C-reactive protein and albumin (termed the modified Glasgow Prognostic Score, mGPS) has been shown to have prognostic value, independent of tumour stage, in lung, gastrointestinal and renal cancers. It is also of interest that liver function tests such as bilirubin, alkaline phosphatase and gamma-glutamyl transferase, as well as serum calcium, have also been reported to predict cancer survival. The aim of the present study was to examine the relationship between an inflammation-based prognostic score (mGPS), biochemical parameters, tumour site and survival in a large cohort of patients with cancer.
METHODS: Patients (n = 21 669) who had an incidental blood sample taken between 2000 and 2006 for C-reactive protein, albumin and calcium (and liver function tests where available) and a diagnosis of cancer were identified. Of this group 9608 patients who had an ongoing malignant process were studied (sampled within 2 years before diagnosis). Also a subgroup of 5397 sampled at the time of diagnosis (sampled within 2 months prior to diagnosis) were examined. Cancers were grouped by tumour site in accordance with International Classification of Diseases 10 (ICD 10).
RESULTS: On follow up, there were 6005 (63%) deaths of which 5122 (53%) were cancer deaths. The median time from blood sampling to diagnosis was 1.4 months. Increasing age, male gender and increasing deprivation was associated with a reduced 5-year overall and cancer-specific survival (all P < 0.001). An elevated mGPS, adjusted calcium, bilirubin, alkaline phosphatase, aspartate transaminase, alanine transaminase and gamma-glutamyl transferase were associated with a reduced 5-year overall and cancer-specific survival (independent of age, sex and deprivation in all patients sampled), as well as within the time of diagnosis subgroup (all P < 0.001). An increasing mGPS was predictive of a reduced cancer-specific survival in all cancers (all P < 0.001).
CONCLUSION: The results of the present study indicate that the mGPS is a powerful prognostic factor when compared with other biochemical parameters and independent of tumour site in patients with cancer
The Relative Importance of Clinical, Economic, Patient Values and Feasibility Criteria in Cancer Drug Reimbursement in Canada:A Revealed Preferences Analysis of Recommendations of the Pan-Canadian Oncology Drug Review 2011–2017
Background: Most Canadian provinces and territories rely on the pan-Canadian Oncology Drug Review (pCODR) to provide recommendations regarding public reimbursement of cancer drugs. The pCODR review process considers four dimensions of value—clinical benefit, economic evaluation, patient-based values and adoption feasibility—but they do not define weights for individual decision criteria or an acceptable threshold for any of the criteria. Given this implicit review process, it is of interest to understand which factors appear to carry the most weight in pCODR recommendations using a revealed preferences approach. Methods: Using publicly available decision summaries (n = 91) describing submissions and resulting recommendations 2011–2017, we extracted ten attributes that characterized each submission. Using logistic regression, we identified statistically significant attributes and estimated their relative impact in final recommendations. Results: Clinical aspects appear to carry the greatest weight in the decision to reject or not reject, along with aspects of patient value (treatments with no alternatives were less likely to be rejected). Cost effectiveness does not appear to play a role in the initial decision to reject or not reject but is critical in full versus conditional approvals. There is evidence of a maximum acceptable threshold of around $Can140,000 per quality-adjusted life-year (QALY) gained. Conclusion: A set of factors driving pCODR recommendations is identifiable, supporting the consistency of the review process. However, the implicit nature of the review process and the difficulty of extracting and interpreting some of the attribute levels used in the analysis suggests that the process may still lack full transparency
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