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Development of an in situ solvent formation microextraction and preconcentration method based on ionic liquids for the determination of trace cobalt (II) in water samples by flame atomic absorption spectrometry
No full textAbstractA simple in situ solvent formation microextraction (ISFME) methodology based on the application of ionic liquid (IL) as an extractant solvent and sodium hexafluorophosphate (NaPF6) as an ion-pairing agent was proposed for the preconcentration of the trace levels of cobalt ions. In this method cobalt was complexed with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and extracted into an ionic liquid phase. After phase separation, the enriched analyte in the final solution is determined by flame atomic absorption spectrometry (FAAS). Some effective factors that influence the microextraction efficiency were investigated and optimized. Under the optimum experimental conditions, the limit of detection and the enrichment factor were 0.97μgL−1 and 50, respectively. The relative standard deviation (R.S.D.) was obtained as 2.4%. The proposed method was assessed through the analysis of certified reference water and recovery experiments
Pollinators in life cycle assessment: towards a framework for impact assessment
No full textAbstractHuman activities are threatening biodiversity at an unprecedented scale and pace, thus potentially affecting also the provision of critical ecosystem services, including insect pollination. Insect pollinators play an essential functional role in terrestrial ecosystems, supporting ecological stability and food security worldwide. Therefore, assessing impact on pollinators is fundamental in any effort aiming at enhancing the environmental sustainability of human production and consumption, especially in the agri-food supply chains. Different drivers are leading to pollinator populations' declines. Improving a supply-chain oriented assessment of the occurrence of pressure and impacts on pollinators is needed. However, current methodologies assessing impact along supply chains, such as life cycle assessment (LCA), miss to assess impact on pollinators. In fact, none of the existing life cycle impact assessment (LCIA) models effectively accounts for pollinators. Some LCIA models have mentioned pollination, but none has presented key drivers of impact and a proposal for integrating pollinators as target group for biodiversity protection within an LCIA framework. In order to devise a pathway towards the inclusion of impacts on pollinators in LCIA, we conducted a literature review of environmental and anthropogenic pressures acting on insect pollinators, potentially threatening pollination services. Based on the evidence in literature, we identified and described eight potential impact drivers, primarily deriving from industrial development and intensive agricultural practice: 1) intensified land use as a result of uncontrolled expansion of urban areas and modern agricultural practices; 2) use of pesticides; 3) presence of invasive alien plants; 4) competition with invasive alien pollinator species; 5) global and local climate change; 6) spread of pests and pathogens; 7) electro-magnetic pollution and 8) genetically modified crops. To account for these drivers in LCIA, there are specific modeling needs. Hence, the current study provides recommendation on how future research should be oriented to improve the current models and how novel indicators should be developed in order to cover the existing conceptual and methodological gaps
Defining greenspace: Multiple uses across multiple disciplines
No full textAbstractGreenspace research has been driven by an emerging interest in the impact that biodiversity and ecosystem function has on life in urban areas. Studies from multiple disciplines across the life, physical and social sciences investigate the interactions with or within greenspace, creating a wide range of potentially related, but disparate findings. In order to understand whether these unconnected findings might be integrated, it is important to be able to make comparisons and build meta-analyses. In a review of journal articles about greenspace, we found that less than half of the 125 journal articles reviewed defined what greenspace was in their study; although many articles implied a definition. In those that provided a definition, we identified two overarching interpretations of greenspace using six different definition types. Perhaps arising from how the term has been lexicalized, this suggests that researchers do not have the same understanding of greenspace and limits the ability of researchers to draw meaning from multiple contexts or create syntheses. Rather than suggest a single, prescriptive understanding of greenspace, we propose that researchers construct a definition of greenspace for the context of their research that utilises both qualitative and quantitative aspects
Diffuse bronchiectasis as the primary manifestation of endobronchial sarcoidosis
No full textAbstractSarcoidosis is an idiopathic disease that most commonly involves the lungs and is characterized by granulomatous inflammation. Bronchiectasis is one pulmonary manifestation of sarcoidosis, although it is almost always observed as traction bronchiectasis in the setting of fibrotic lung disease. A 50-year-old woman was evaluated for chronic cough and bronchiectasis with a small amount of peripheral upper lobe honeycombing and no significant pulmonary fibrosis or lymphadenopathy. After an extensive laboratory and imaging evaluation did not identify a cause of her bronchiectasis, bronchoscopy was performed to assess for primary ciliary dyskinesia and revealed a diffuse cobblestone appearance of the airway mucosa. Endobronchial biopsies and lymphocyte subset analysis of bronchoalveolar lavage fluid were consistent with a diagnosis of sarcoidosis. We believe endobronchial sarcoidosis should be included in the differential diagnosis of patients presenting with bronchiectasis
Age at menarche and risk of major cardiovascular diseases: Evidence of birth cohort effects from a prospective study of 300,000 Chinese women
No full textAbstractBackgroundPrevious studies of mostly Western women have reported inconsistent findings on the association between age at menarche and risk of cardiovascular disease (CVD). Little is known about the association in China where there has been a large intergenerational decrease in women's mean age at menarche.MethodsThe China Kadoorie Biobank recruited 302,632 women aged 30–79 (mean 50.5)years in 2004–8 from 10 diverse regional sites across China. During 7years follow-up, 14,111 incident cases of stroke, 14,093 of coronary heart disease (CHD), and 3200 CVD deaths were reported among 281,491 women who had no prior history of CVD at baseline. Cox regression yielded adjusted hazard ratios (HRs) relating age at menarche to CVD risks.ResultsThe mean (SD) age of menarche was 15.4 (1.9)years, decreasing from 16.2 (2.0) among women born before 1940 to 14.7 (1.6) for those born during the 1960s–1970s. The patterns of association between age at menarche and CVD risk appeared to differ between different birth cohorts, with null associations in older generations but U-shaped or weak positive associations in younger women, especially those born after the 1960s. After minimizing the potential confounding effects from major CVD risk factors, both early and late menarche, compared with menarche at age 13years, were associated with increased risk of CVD morbidity and mortality, which was more pronounced in younger generations.ConclusionAmong Chinese women the associations between age at menarche and risk of CVD differed by birth cohort, suggesting other factors may underpin the association
Intra-ring haptotropic rearrangements of Mn(CO)3 in fluorenyl ligands
No full textAbstractGeometric parameters, and intra-ring haptotropic rearrangements π–π (intra-ring-HRs) ŋ5⇌ŋ3 of the manganesetricarbonyl complexes (ŋ5-9-R-C13H8)Mn(CO)3, R=But and Ph in 18e zero-valence are carried out using density functional theory DFT at PBE/TZP level. The calculated activation barriers to ŋ5⇌ŋ3 intra-ring HR in (ŋ5-9-R-C13H8)Mn(CO)3, R=But and Ph are (28.5 and 69.5kcal.mol−1 respectively). The compute of HOMA and FLU indexes indicates the reduction of aromaticity when going from free to coordinated complex. The energy decomposition analysis reveals the dominant ionic character in manganese–Cp bond in the presence of covalent contribution
Heart rate control by carvedilol in Japanese patients with chronic atrial fibrillation: The AF Carvedilol study
No full textAbstractBackgroundβ-Blockers are used to control heart rate (HR) in patients with atrial fibrillation (AF). However, the appropriate dosage and efficacy of carvedilol in Japanese AF patients are yet to be clarified.MethodsIn this multicenter, randomized, double-blind study, Japanese patients with persistent or permanent AF received carvedilol for 6 weeks in the following three dosage-regimen groups: 5-mg fixed-dose (n=42), 10-mg dose-escalation (n=42), or 20-mg dose-escalation (n=43). To evaluate the efficacy of each dosage regimen and the dose–response relationship, changes in 24-h mean HR (mHR) on Holter electrocardiograms from baseline to weeks 2, 4, and 6 were determined as primary endpoints. The effects on circadian changes in HR, the proportion of patients achieving target HR, clinical symptoms, and adverse events were also examined.ResultsAfter 2 weeks, carvedilol 5mg decreased 24-h mHR significantly [6.6 (95% CI: 5.2–8.0)beats/min, p<0.0001]. After 6 weeks, carvedilol showed a trend of dose-dependent HR reduction (p=0.0638): 7.6 (5.4–9.8) in the 5-mg fixed-dose group; 8.9 (6.7–11.1) in the 10-mg dose-escalation group; and 10.6 (8.4–12.8)beats/min in the 20-mg dose-escalation group. There were no serious adverse events related to carvedilol.ConclusionsIn Japanese patients with persistent or permanent AF, carvedilol at 5mg once daily demonstrated a significant HR reduction, and step-wise dose escalation from 5mg to 20mg showed a trend of dose-dependent HR reduction
Ground-state properties of even and odd Magnesium isotopes in a symmetry-conserving approach
No full textAbstractWe present a self-consistent theory for odd nuclei with exact blocking and particle number and angular momentum projection. The demanding treatment of the pairing correlations in a variation-after-projection approach as well as the explicit consideration of the triaxial deformation parameters in a projection after variation method, together with the use of the finite-range density-dependent Gogny force, provides an excellent tool for the description of odd–even and even–even nuclei. We apply the theory to the Magnesium isotopic chain and obtain an outstanding description of the ground-state properties, in particular binding energies, odd–even mass differences, mass radii and electromagnetic moments among others
Delayed CO2 emissions from mid-ocean ridge volcanism as a possible cause of late-Pleistocene glacial cycles
No full textAbstractThe coupled 100,000 year variations in ice volume, temperature, and atmospheric CO2 during the late Pleistocene are generally considered to arise from a combination of orbital forcing, ice dynamics, and ocean circulation. Also previously argued is that changes in glaciation influence atmospheric CO2 concentrations through modifying subaerial volcanic eruptions and CO2 emissions. Building on recent evidence that ocean ridge volcanism responds to changes in sea level, here it is suggested that ocean ridges may play an important role in generating late-Pleistocene 100 ky glacial cycles. If all volcanic CO2 emissions responded immediately to changes in pressure, subaerial and ocean-ridge volcanic emissions anomalies would oppose one another. At ocean ridges, however, the egress of CO2 from the mantle is likely to be delayed by tens-of-thousands of years, or longer, owing to ascent time. A simple model involving temperature, ice, and CO2 is presented that oscillates at ∼100 ky time scales when incorporating a delayed CO2 contribution from ocean ridge volcanism, even if the feedback accounts for only a small fraction of total changes in CO2. Oscillations readily become phase-locked with insolation forcing associated with changes in Earth's orbit. Under certain parameterizations, a transition from ∼40 ky to larger ∼100 ky oscillations occurs during the middle Pleistocene in response to modulations in orbital forcing. This novel description of Pleistocene glaciation should be testable through ongoing advances in understanding the circulation of carbon through the solid earth
A state-of-the-art review and feasibility analysis of high altitude wind power in Northern Ireland
No full textAbstractIn many countries wind energy has become an indispensable part of the electricity generation mix. The opportunity for ground based wind turbine systems are becoming more and more constrained due to limitations on turbine hub heights, blade lengths and location restrictions linked to environmental and permitting issues including special areas of conservation and social acceptance due to the visual and noise impacts. In the last decade there have been numerous proposals to harness high altitude winds, such as tethered kites, airfoils and dirigible based rotors. These technologies are designed to operate above the neutral atmospheric boundary layer of 1300m, which are subject to more powerful and persistent winds thus generating much higher electricity capacities. This paper presents an in-depth review of the state-of-the-art of high altitude wind power, evaluates the technical and economic viability of deploying high altitude wind power as a resource in Northern Ireland and identifies the optimal locations through considering wind data and geographical constraints. The key findings show that the total viable area over Northern Ireland for high altitude wind harnessing devices is 5109.6km2, with an average wind power density of 1998W/m2 over a 20-year span, at a fixed altitude of 3000m. An initial budget for a 2MW pumping kite device indicated a total cost £1,751,402 thus proving to be economically viable with other conventional wind-harnessing devices