Sustainability analysis of bioethanol production from grain and tuber starchy feedstocks.

A comparative sustainability study of bioethanol production from selected starchy feedstocks that are abundantly available was carried out in this work. This is to ensure the safe, reliable, and efficient production and consumption of fuel-grade bioethanol. The analysis utilised the established economic minimum bioethanol plant capacity of 158,000 m3/annum. The processing flowsheet model utilised was the same for each feedstock. The sustainability study's economic, environmental, and energy perspectives were investigated. The economic and environmental indices were assessed using Superpro Designer and openLCA sustainability software, respectively. Exergy and lost work were subsequently estimated manually with Microsoft Excel. The economic analyses showed that the plants using cassava and sweet potato initially had the highest return on investment (ROI) of 64.41 and 41.96% respectively at a minimum of 80% plants' capacity utilisation. The break-even point occurs at a bioethanol price of $3.27 per gallon, beyond which positive net present values were obtained for the four processes. The least profitable plant was based on sorghum recording an ROI value of 34.11%. The environmental assessment on the four selected feedstocks showed that the processes based on cassava, corn, sweet potato, and sorghum recorded encouraging global warming potential (GWP) of 0.2452, 0.2067, 2.5261, and 0.2099 kg CO2 equivalent respectively. Cassava and corn emerged as the two most economically viable feedstocks when economic parameters were adjusted to include pollutants emission/discharge costs but with a slight decrease in profitability indices. The lost work analyses showed that distillation columns were the least energy-efficient units in the four bioethanol production routes assessed, recording loss work of about 61, 68, 34, and 49 MW for cassava, sweet potato, corn, and sorghum processing plants respectively. However, the net energy balance (NEB) and energy renewability results of the four production routes showed that the processes utilising the four selected starchy biomass feedstocks are more sustainable compared to fossil fuels.

Real-space texture and pole-figure analysis using the 3D pair distribution function on a platinum thin film.

An approach is described for studying texture in nanostructured materials. The approach implements the real-space texture pair distribution function (PDF), txPDF, laid out by Gong & Billinge {(2018 ▸). arXiv:1805.10342 [cond-mat]}. It is demonstrated on a fiber-textured polycrystalline Pt thin film. The approach uses 3D PDF methods to reconstruct the orientation distribution function of the powder crystallites from a set of diffraction patterns, taken at different tilt angles of the substrate with respect to the incident beam, directly from the 3D PDF of the sample. A real-space equivalent of the reciprocal-space pole figure is defined in terms of interatomic vectors in the PDF and computed for various interatomic vectors in the Pt film. Furthermore, it is shown how a valid isotropic PDF may be obtained from a weighted average over the tilt series, including the measurement conditions for the best approximant to the isotropic PDF from a single exposure, which for the case of the fiber-textured film was in a nearly grazing incidence orientation of ∼10°. Finally, an open-source Python software package, FouriGUI, is described that may be used to help in studies of texture from 3D reciprocal-space data, and indeed for Fourier transforming and visualizing 3D PDF data in general.

Imaging Cu2O nanocube hollowing in solution by quantitative in situ X-ray ptychography.

Understanding morphological changes of nanoparticles in solution is essential to tailor the functionality of devices used in energy generation and storage. However, we lack experimental methods that can visualize these processes in solution, or in electrolyte, and provide three-dimensional information. Here, we show how X-ray ptychography enables in situ nano-imaging of the formation and hollowing of nanoparticles in solution at 155 °C. We simultaneously image the growth of about 100 nanocubes with a spatial resolution of 66 nm. The quantitative phase images give access to the third dimension, allowing to additionally study particle thickness. We reveal that the substrate hinders their out-of-plane growth, thus the nanocubes are in fact nanocuboids. Moreover, we observe that the reduction of Cu2O to Cu triggers the hollowing of the nanocuboids. We critically assess the interaction of X-rays with the liquid sample. Our method enables detailed in-solution imaging for a wide range of reaction conditions.

X-ray studies bridge the molecular and macro length scales during the emergence of CoO assemblies.

The key to fabricating complex, hierarchical materials is the control of chemical reactions at various length scales. To this end, the classical model of nucleation and growth fails to provide sufficient information. Here, we illustrate how modern X-ray spectroscopic and scattering in situ studies bridge the molecular- and macro- length scales for assemblies of polyhedrally shaped CoO nanocrystals. Utilizing high energy-resolution fluorescence-detected X-ray absorption spectroscopy, we directly access the molecular level of the nanomaterial synthesis. We reveal that initially Co(acac)3 rapidly reduces to square-planar Co(acac)2 and coordinates to two solvent molecules. Combining atomic pair distribution functions and small-angle X-ray scattering we observe that, unlike a classical nucleation and growth mechanism, nuclei as small as 2 nm assemble into superstructures of 20 nm. The individual nanoparticles and assemblies continue growing at a similar pace. The final spherical assemblies are smaller than 100 nm, while the nanoparticles reach a size of 6 nm and adopt various polyhedral, edgy shapes. Our work thus provides a comprehensive perspective on the emergence of nano-assemblies in solution.

Febrile illness experience among Nigerian nomads.

BACKGROUND: An understanding of the febrile illness experience of Nigerian nomadic Fulani is necessary for developing an appropriate strategy for extending malaria intervention services to them. An exploratory study of their malaria illness experience was carried out in Northern Nigeria preparatory to promoting malaria intervention among them. METHODS: Ethnographic tools including interviews, group discussions, informal conversations and living-in-camp observations were used for collecting information on local knowledge, perceived cause, severity and health seeking behaviour of nomadic Fulani in their dry season camps at the Gongola-Benue valley in Northeastern Nigeria. RESULTS: Nomadic Fulani regarded pabboje (a type of "fever" that is distinct from other fevers because it "comes today, goes tomorrow, returns the next") as their commonest health problem. Pabboje is associated with early rains, ripening corn and brightly coloured flora. Pabboje is inherent in all nomadic Fulani for which treatment is therefore unnecessary despite its interference with performance of duty such as herding. Traditional medicines are used to reduce the severity, and rituals carried out to make it permanently inactive or to divert its recurrence. Although modern antimalaria may make the severity of subsequent pabboje episodes worse, nomads seek treatment in private health facilities against fevers that are persistent using antimalarial medicines. The consent of the household head was essential for a sick child to be treated outside the camp. The most important issues in health service utilization among nomads are the belief that fever is a Fulani illness that needs no cure until a particular period, preference for private medicine vendors and the avoidance of health facilities. CONCLUSIONS: Understanding nomadic Fulani beliefs about pabboje is useful for planning an acceptable community participatory fever management among them.

Epidemiology of HIV-tuberculosis co-Infection among patients on anti-retroviral therapy in Sokoto State, Nigeria

"Background: Human immunodeficiency virus/acquired immune deficiency syndrome and tuberculosis are commonly called the ""deadly duo""; because human immunodeficiency virus increases susceptibility to tuberculosis which in turn accelerates its progression to acquired immune deficiency syndrome. This study describes human immunodeficiency virus/ tuberculosis co-infection in Sokoto State; Nigeria. Methods: Data were extracted from medical records of human immunodeficiency virus infected patients on antiretroviral therapy in health facilities that offer comprehensive care for human immunodeficiency virus infected patients in Sokoto State; and analysed. Results: Majority of the 353 study subjects were females (60.6) aged 30-39 years (37.4) and living in Sokoto state (78.5). Care entry points were Medical Outpatient Department (36.8); General Outpatient Department (35.4) and voluntary counseling centre (23.5). Enrolment for human immunodeficiency virus care was highest in May (13.4) and lowest in March (5.1). The functional status of majority (75.8) of the study subjects was asymptomatic normal activity. Thirty-three (9.3) of the study subjects were human immunodeficiency virus/Tuberculosis co-infected. Human immune deficiency virus only cases and human immunodeficiency virus/Tuberculosis co-infected cases were similar with respect to age and sex but differed significantly with respect to WHO clinical stage; CD4 count and functional status. Conclusion: Human immunodeficiency virus only and human immunodeficiency virus/tuberculosis coinfection cases have similar demographic characteristics but differ with respect to the stage of acquired immune deficiency syndrome."

Bone marrow and renal injury associated with haloalkene cysteine conjugates in calves.

Almost 40 years ago, it was reported that cattle-feed which had been extracted with hot trichloroethylene and then fed to calves produced renal injury and a fatal aplastic anaemia. The toxic factor was subsequently identified as S-(1,2-dichlorovinyl)-L-cysteine (DCVC). These original findings have been confirmed, a single intravenous dose of DCVC at 4 mg/kg, or 0.4 mg/kg intravenously per day administered for 10 days to calves produced aplastic anaemia, and renal injury after a single dose of 4 mg/kg. The toxicity to calves of a number of other haloalkene cysteine conjugates has been examined to ascertain whether, like DCVC, they produce bone marrow and renal injury. Intravenous administration of the N-acetyl cysteine conjugate of DCVC produced renal but not bone marrow injury at a molar equivalent dose to DCVC, indicating that the calf can deacetylate the mercapturic acid and further that sufficient chemical had reached the kidney to be a substrate for the enzyme cysteine conjugate beta-lyase. However, intravenous administration of the alpha-methyl analogue of DCVC, which cannot undergo metabolism via the enzyme cysteine conjugate beta-lyase, was without toxicity at doses about five-fold higher than DCVC. These latter findings provide strong evidence that metabolism of DCVC via the enzyme beta-lyase is necessary for bone marrow and renal injury to occur. The cysteine conjugates of perchloroethylene and hexachloro-1,3-butadiene(HCBD) when given intravenously to calves at molar equivalent doses to DCVC, or above, did not produce either bone marrow or renal injury. In contrast, intravenous administration of the cysteine conjugate of tetrafluoroethylene (TFEC) produced severe renal tubular injury in calves without affecting the bone marrow. In vitro studies with these haloalkene cysteine conjugates showed, like DCVC, that they were good substrates for calf renal cysteine conjugate beta-lyase and toxic to renal cells as judged by their ability to reduce organic anion and cation transport by slices of calf renal cortex and inhibit the renal enzyme glutathione reductase. Calves were also dosed either orally or intravenously with HCBD to assess its toxicity. HCBD at higher molar equivalent doses than DCVC produced mid-zonal necrosis in the liver, renal tubular necrosis but no bone marrow injury in calves. The key findings emerging from these studies are (1) that none of the other cysteine conjugates, at molar equivalent doses to DCVC and above, produce bone marrow injury in calves, (2) TFEC produced only renal injury, suggesting that sufficient of the other conjugates had not reached the kidney for metabolism by beta-lyase to produce cytotoxicity and (3) that HCBD itself is more toxic than its cysteine or mercapturic acid conjugate, suggesting that pharmaco-kinetics and disposition are important factors in determining the toxicity of these conjugates to calves. Further studies are needed to understand the basis for the selective toxicity of DCVC to the bone marrow of calves.