Non-perturbative embedding of local defects in crystalline materials

We present a new variational model for computing the electronic first-order density matrix of a crystalline material in presence of a local defect. A natural way to obtain variational discretizations of this model is to expand the difference Q between the density matrix of the defective crystal and the density matrix of the perfect crystal, in a basis of precomputed maximally localized Wannier functions of the reference perfect crystal. This approach can be used within any semi-empirical or Density Functional Theory framework.Comment: 13 pages, 4 figure

Carbon emissions from fossil fuel consumption of Beijing in 2012

The present study analyzed the consumption-based carbon emissions from fossil fuel consumption of Beijing in 2012. The multi-scale input–output analysis method was applied. It is capable of tracing the carbon emissions embodied in imports based on a global multi-regional input–output analysis using Eora data. The results show that the consumption-based carbon emission of Beijing has increased by 18% since 2007, which is 2.57 times higher than the production-based carbon emission in 2012. Only approximately 1/10 of the total carbon emissions embodied in Beijing's local final demand originated from local direct carbon emissions. Meanwhile, more than 4/5 were from domestically imported products. The carbon emission nexus between Beijing and other Chinese regions has become closer since 2007, while the imbalance as the carbon emission transfer from Beijing to other regions has been mitigated. Instead, Beijing has imported more carbon emissions from foreign countries. Some carbon emission reduction strategies for Beijing concerning different goals are presented on the basis of detailed discussion

Exact exchange-correlation potential of a ionic Hubbard model with a free surface

We use Lanczos exact diagonalization to compute the exact exchange-correlation (xc) potential of a Hubbard chain with large binding energy ("the bulk") followed by a chain with zero binding energy ("the vacuum"). Several results of density functional theory in the continuum (sometimes controversial) are verified in the lattice. In particular we show explicitly that the fundamental gap is given by the gap in the Kohn-Sham spectrum plus a contribution due to the jump of the xc-potential when a particle is added. The presence of a staggered potential and a nearest-neighbor interaction V allows to simulate a ionic solid. We show that in the ionic regime in the small hopping amplitude limit the xc-contribution to the gap equals V, while in the Mott regime it is determined by the Hubbard U interaction. In addition we show that correlations generates a new potential barrier at the surface

Effect of GSM Radiation on White Blood Cells

The effect of continuous-wave radiation on peripheral blood in albino mice was investigated. A radiation frequency of 2450MHz was applied at an average power density of induced field 10mW/cm2. Ten 13 week old albino mice with average body mass of 35.0g were divided into 3 groups, preliminary group, control group, C and the irradiated group, E. Two (2) mice were used for preliminary studies, four (4) were kept to serve as control batch, and four (4) were exposed to microwaves for 60 days, at 2 hours per day. Peripheral blood samples were taken immediately after irradiation on the 1st, 16th, 32nd and the 60th day of the experiment. The total white blood cells count of both control, C batch and exposed, E batch, as well as the differential white blood cells count were investigated. The morphology of cells was also observed, during each session of the investigation in comparison with control C batch. The results revealed a decrease in the total white cell count which consistently continued in irradiated E batch from the 1st day of irradiation in the sample of the irradiated E batch in comparison with the control C batch samples. Slight increase in relative proportion of the neutrophil was observed in E batch sample in comparison with the C batch samples. Our investigation confirms wave exposure affects the white blood cells parameters of exposed animals

Health-seeking behaviour of tuberculosis patients and related factors in the central region of Ghana

The health seeking behaviour of TB patients and health service related barriers have been cited to have an influence on the management of the disease in countries with high incidence of TB. Using close and open-ended questionnaires, an assessment of the health seeking behaviour of 302 TB patients selected from 24 DOTS centres in six districts in the Central  Region of Ghana was carried out. Under service-related barriers, distance from home to DOTS centre significantly impacted on the management of TB among sufferers (p=0.025). Though not significant, patients  acknowledged the good reception by staff at treatment centres with 99.3% of them being comfortable with staff and services provided at centres. Majority (46.7%) of patients perceived TB to be caused by the oral route while only 9.3% knew the causative agent to be bacteria. Compared with males, quite a number of women did not have adequate knowledge on TB (p<0.05). More than half of the respondents sought treatment elsewhere as first point of treatment before reporting to the DOTS centre. Health insurance played an important role in the health seeking behaviour of respondents; 45.9% of TB patients with health insurance visited the health facility as 1st provider whilst 49.4% without health insurance visited prayer camps (p=0.001). Our study has revealed that factors such as staff  attitude, distance to treatment centres, gender, employment and education are key factors that affect the health-seeking behaviour of TB patients in the Central Region of GhanaKeywords: Tuberculosis, Health, barriers, Central Regio

In vivo anti-malarial potentials of some plants extracts on ICR-mice, Mus musculus

Five medicinal plants, Acacia nilotica (Fabaceae), Citrus aurantifolia (Rutaceae), Mangifera indica (Anacardiaceae) Carica papaya (Caricaceae), and Psidium guajava (Myrtaceae) used for the treatment of malaria/ fever by the Hausa people of Kano-Nigeria were selected based on their traditional claims. These were extracted using ethanol. The in vitro antiplasmodial activities of these extracts against laboratory adapted chloroquine susceptible strain of Plasmodium falciparum (3D7) were earlier reported (Dabo et al. 2013). This study was conducted to evaluate the in vivo antiplasmodial activity of four of these extracts using icr mice in the 4-day suppressive test against P. berghei. The extracts evaluated were: Acacia nilotica (Fabaceae) stem extract coded as ANSF1; Citrus aurantifolia (Rutaceae) leaf extract coded as CALF1; Mangifera indica (Anacardiaceae) leaf extract coded as MILF1 and combination of C. aurantifolia, Carica papaya (Caricaceae), M. indica and Psidium guajava (Myrtaceae) leaves extract coded as CBLF1. CALF1, ANSF1 and CBLF1 (combination) exhibited appreciable degree of suppression of 31.06%, 25.16 and %16.35% respectively. MILF1 did not exhibit any suppression against the P. berghei parasite in vivo at all. With the exception of haemoglobin content (P<0.0363), haematological analysis of the various blood parameters of mice in the control and treated mice indicated no statistical difference (P>0.05). Thus it can be concluded that, the apparent absence of changes in haematological profile alongside activities exhibited by CALF1 (Rutaceae), CBLF1 (a combination) and ANSF1 (Fabaceae),) suggest the bio-availability and antiplasmodial activities of the active substances in the plants evaluated.Keywords: Antimalaria; In vivo, Plants Extracts; Mus musculus; Plasmodium berghei

Reduced carbon emission estimates from fossil fuel combustion and cement production in China.

Nearly three-quarters of the growth in global carbon emissions from the burning of fossil fuels and cement production between 2010 and 2012 occurred in China. Yet estimates of Chinese emissions remain subject to large uncertainty; inventories of China's total fossil fuel carbon emissions in 2008 differ by 0.3 gigatonnes of carbon, or 15 per cent. The primary sources of this uncertainty are conflicting estimates of energy consumption and emission factors, the latter being uncertain because of very few actual measurements representative of the mix of Chinese fuels. Here we re-evaluate China's carbon emissions using updated and harmonized energy consumption and clinker production data and two new and comprehensive sets of measured emission factors for Chinese coal. We find that total energy consumption in China was 10 per cent higher in 2000-2012 than the value reported by China's national statistics, that emission factors for Chinese coal are on average 40 per cent lower than the default values recommended by the Intergovernmental Panel on Climate Change, and that emissions from China's cement production are 45 per cent less than recent estimates. Altogether, our revised estimate of China's CO2 emissions from fossil fuel combustion and cement production is 2.49 gigatonnes of carbon (2 standard deviations = ±7.3 per cent) in 2013, which is 14 per cent lower than the emissions reported by other prominent inventories. Over the full period 2000 to 2013, our revised estimates are 2.9 gigatonnes of carbon less than previous estimates of China's cumulative carbon emissions. Our findings suggest that overestimation of China's emissions in 2000-2013 may be larger than China's estimated total forest sink in 1990-2007 (2.66 gigatonnes of carbon) or China's land carbon sink in 2000-2009 (2.6 gigatonnes of carbon).This is the author accepted manuscript. The final version is available from NPG via http://dx.doi.org/10.1038/nature1467

Synthesis of Bulk Calcium Oxide (CaO) Catalyst and its Efficacy for Biodiesel Production

The numerous limitations of the conventional homogenous catalysts have become a great challenge for researchers in the area of biodiesel. Therefore, alternative catalysts for clean and environmental benign process is the solution. Calcium oxide catalyst was prepared from hydrated lime and it was used to produce biodiesel to test its efficacy. It was used to catalyze transesterification of Jatropha curcas oil and methanol at 600C reaction temperature for 50, 60, 70, 80 and 90 minutes reaction times and the corresponding biodiesel yield of 94.76%, 98.67, 100.00, 89.92 and 99.08% were obtained. The components of methyl ester found in the five samples of the biodiesel are listed. Key words: synthesis, calcium oxide, catalyst, biodiesel, productio

Transboundary health impacts of transported global air pollution and international trade

Millions of people die every year from diseases caused by exposure to outdoor air pollution1, 2, 3, 4, 5. Some studies have estimated premature mortality related to local sources of air pollution6, 7, but local air quality can also be affected by atmospheric transport of pollution from distant sources8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18. International trade is contributing to the globalization of emission and pollution as a result of the production of goods (and their associated emissions) in one region for consumption in another region14, 19, 20, 21, 22. The effects of international trade on air pollutant emissions23, air quality14 and health24 have been investigated regionally, but a combined, global assessment of the health impacts related to international trade and the transport of atmospheric air pollution is lacking. Here we combine four global models to estimate premature mortality caused by fine particulate matter (PM2.5) pollution as a result of atmospheric transport and the production and consumption of goods and services in different world regions. We find that, of the 3.45 million premature deaths related to PM2.5 pollution in 2007 worldwide, about 12 per cent (411,100 deaths) were related to air pollutants emitted in a region of the world other than that in which the death occurred, and about 22 per cent (762,400 deaths) were associated with goods and services produced in one region for consumption in another. For example, PM2.5 pollution produced in China in 2007 is linked to more than 64,800 premature deaths in regions other than China, including more than 3,100 premature deaths in western Europe and the USA; on the other hand, consumption in western Europe and the USA is linked to more than 108,600 premature deaths in China. Our results reveal that the transboundary health impacts of PM2.5 pollution associated with international trade are greater than those associated with long-distance atmospheric pollutant transport

Global climate forcing of aerosols embodied in international trade

International trade separates regions consuming goods and services from regions where goods and related aerosol pollution are produced. Yet the role of trade in aerosol climate forcing attributed to different regions has never been quantified. Here, we contrast the direct radiative forcing of aerosols related to regions’ consumption of goods and services against the forcing due to emissions produced in each region. Aerosols assessed include black carbon, primary organic aerosol, and secondary inorganic aerosols, including sulfate, nitrate and ammonium. We find that global aerosol radiative forcing due to emissions produced in East Asia is much stronger than the forcing related to goods and services ultimately consumed in that region because of its large net export of emissions-intensive goods. The opposite is true for net importers such as Western Europe and North America: global radiative forcing related to consumption is much greater than the forcing due to emissions produced in these regions. Overall, trade is associated with a shift of radiative forcing from net importing to net exporting regions. Compared to greenhouse gases such as carbon dioxide, the short atmospheric lifetimes of aerosols cause large localized differences between consumption- and production-related radiative forcing. International efforts to reduce emissions in the exporting countries will help alleviate trade-related climate and health impacts of aerosols while lowering global emissions