Comparative energetic assessment of methanol production from CO₂: chemical versus electrochemical process

Emerging emission-to-liquid (eTL) technologies that produce liquid fuels from CO₂ are a possible solution for both the global issues of greenhouse gas emissions and fossil fuel depletion. Among those technologies, CO₂ hydrogenation and high-temperature CO₂ electrolysis are two promising options suitable for large-scale applications. In this study, two CO₂ -to-methanol conversion processes, i.e., production of methanol by CO₂ hydrogenation and production of methanol based on high-temperature CO₂ electrolysis, are simulated using Aspen HYSYS. With Aspen Energy Analyzer, heat exchanger networks are optimized and minimal energy requirements are determined for the two different processes. The two processes are compared in terms of energy requirement and climate impact. It is found that the methanol production based on CO₂ electrolysis has an energy efficiency of 41%, almost double that of the CO₂ hydrogenation process provided that the required hydrogen is sourced from water electrolysis. The hydrogenation process produces more CO₂ when fossil fuel energy sources are used, but can result in more negative CO₂ emissions with renewable energies. The study reveals that both of the eTL processes can outperform the conventional fossil-fuel-based methanol production process in climate impacts as long as the renewable energy sources are implemented

Presentation of Epilepsy in a Patient with Wilson's Disease and Developmental Venous Anomaly (Venous Angioma) in the Brain

Intracranial developmental venous anomalies (DVAs), also called venous angiomas, and Wilson's disease are both considered rare disorders with varying degrees of neurologic and systemic manifestations; yet the coexistence of the two disorders is considered extremely rare, bearing in mind the low prevalence of each disorder. Epilepsy is a recognised presentation in these disorders and will be the focus of discussion in our report of a 21-year-old male patient who, based on a clinical examination and laboratory and neuroimaging results, was diagnosed with both Wilson's disease and DVA. He presented initially at Sultan Qaboos University Hospital, Oman with tremors and writing difficulties in the right hand followed by the development of epilepsy, and was treated medically by de-coppering and antiepileptic medications. We also present a brief literature review of both disorders, their association with epilepsy, and treatment options. Family screening for patients with Wilson’s disease is pivotal in preventing unfavourable outcomes.

From DPSIR the DAPSI(W)R(M) Emerges… a Butterfly – ‘protecting the natural stuff and delivering the human stuff’

The complexity of interactions and feedbacks between human activities and ecosystems can make the analysis of such social-ecological systems intractable. In order to provide a common means to understand and analyse the links between social and ecological process within these systems, a range of analytical frameworks have been developed and adopted. Following decades of practical experience in implementation, the Driver Pressure State Impact Response (DPSIR) conceptual framework has been adapted and re-developed to become the D(A)PSI(W)R(M). This paper describes in detail the D(A)PSI(W)R(M) and its development from the original DPSIR conceptual frame. Despite its diverse application and demonstrated utility, a number of inherent shortcomings are identified. In particular the DPSIR model family tend to be best suited to individual environmental pressures and human activities and their resulting environmental problems, having a limited focus on the supply and demand of benefits from nature. We present a derived framework, the “Butterfly”, a more holistic approach designed to expand the concept. The “Butterfly” model, moves away from the centralised accounting framework approach while more-fully incorporating the complexity of social and ecological systems, and the supply and demand of ecosystem services, which are central to human-environment interactions

Effect of surgical experience and spine subspecialty on the reliability of the {AO} Spine Upper Cervical Injury Classification System

OBJECTIVE The objective of this paper was to determine the interobserver reliability and intraobserver reproducibility of the AO Spine Upper Cervical Injury Classification System based on surgeon experience (< 5 years, 5–10 years, 10–20 years, and > 20 years) and surgical subspecialty (orthopedic spine surgery, neurosurgery, and "other" surgery). METHODS A total of 11,601 assessments of upper cervical spine injuries were evaluated based on the AO Spine Upper Cervical Injury Classification System. Reliability and reproducibility scores were obtained twice, with a 3-week time interval. Descriptive statistics were utilized to examine the percentage of accurately classified injuries, and Pearson’s chi-square or Fisher’s exact test was used to screen for potentially relevant differences between study participants. Kappa coefficients (κ) determined the interobserver reliability and intraobserver reproducibility. RESULTS The intraobserver reproducibility was substantial for surgeon experience level (< 5 years: 0.74 vs 5–10 years: 0.69 vs 10–20 years: 0.69 vs > 20 years: 0.70) and surgical subspecialty (orthopedic spine: 0.71 vs neurosurgery: 0.69 vs other: 0.68). Furthermore, the interobserver reliability was substantial for all surgical experience groups on assessment 1 (< 5 years: 0.67 vs 5–10 years: 0.62 vs 10–20 years: 0.61 vs > 20 years: 0.62), and only surgeons with > 20 years of experience did not have substantial reliability on assessment 2 (< 5 years: 0.62 vs 5–10 years: 0.61 vs 10–20 years: 0.61 vs > 20 years: 0.59). Orthopedic spine surgeons and neurosurgeons had substantial intraobserver reproducibility on both assessment 1 (0.64 vs 0.63) and assessment 2 (0.62 vs 0.63), while other surgeons had moderate reliability on assessment 1 (0.43) and fair reliability on assessment 2 (0.36). CONCLUSIONS The international reliability and reproducibility scores for the AO Spine Upper Cervical Injury Classification System demonstrated substantial intraobserver reproducibility and interobserver reliability regardless of surgical experience and spine subspecialty. These results support the global application of this classification system

A Conceptual Framework for Information Security in Public Organizations for E-Government Development

The rapid development of e-government across the world has exposed critical information in public organizations to the possibility of cybercrime. Information security has become a critical issue that needs to be adequately addressed in e-government development. This paper proposes a conceptual framework for information security compliance. The proposed framework, consisting of four dimensions - organizational security culture, operational process, technology, and environment - was validated using semi-structured interviews with security managers in public organizations involved in e-government development in Oman. This paper contributes to information security research by identifying the critical factors for adopting an information security compliance approach to increase information security for e-government development in public organizations

Information Security Compliance in Organizations: An Institutional Perspective

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Fog and Rain Water Collection from Trees in the Dhofar Region in the Sultanate of Oman

This work had two purposes. The first was to measure and investigate the amount of fog and rain water collected by a sample of trees during the summer monsoon season in the mountains of the Dhofar region in the south of Oman. The second purpose was to assess the potential of trees with different leaf shapes, sizes and cross sectional canopy areas to collect fog and rain water in the area. In order to meet these purposes three different tree species, were selected for experimental investigation and field measurements. They included fig, lemon, and tamarind trees. The experiments were designed and implemented in the monsoon season of 2006, between the 13th of July and the 3rd of September. The daily measurements of water collection showed that the three species of tree have different water collection capacities. It was found that the fig tree collected the least water. The fog water collection of the fig tree over a period of 47 days between the 13th of July and the 3rd of September was 140.5 L/m2, or an average of 2.7 L/m2/d. The fog water collection of the lemon tree was 243.0 L/m2, or an average of 4.4 L/m2/d. In terms of potential collection of the tamarind tree, the results showed that it collected a fog water of 218.9 L/m2, or an average of 4.3 L/m2/d over the same period. The study contributes to the knowledge of how different tree species collect fog and rain water, and concludes with a set of recommendations

Development and morphological changes in leaves and branches of acid lime (Citrus aurantifolia) affected by witches\u2019 broom disease

Witches\u2019 broom (WB), associated with the presence of \u2018Candidatus Phytoplasma aurantifolia\u2019, is one of the most serious diseases of acid lime. This study determined incidence, distribution, and development of the dis-ease, and morphological changes in leaves and branches of affected host plants. Survey in different parts of Oman showed that WB occurs in most regions in the country, where 108 out of 158 (68%) surveyed farms were found to have diseased trees. A survey of 6,926 acid lime trees showed that severity of WB was positively related (r = 0.948; P<0.01) to tree age. The mean percentage of symptomatic branches was 1% in 3-year-old trees compared to 63% in 12-year-old trees. To further characterize morphological changes in WB-affected limes, apical stems (40 cm long) were collected from three infected trees during the autumn of 2009 and spring of 2010. Increases in the numbers of leaves (1,208%), numbers of branches (309%) and total length of branches (712%) were recorded for symptomatic branches relative to non-symptomatic branches. In the spring of 2009 these respective increases were 159%, 243% and 121%.Overall area of leaves in the symptomatic branches was 81% less than for non-symptomatic branches in the autumn of 2009 and 34% less in the spring of 2010. This study is the first to characterize morphological changes in leaves and branches of acid lime affected by WB

The effect of sildenafil on rats with adenine-Induced chronic kidney disease

Karaca, Turan (Trakya author)The erectile dysfunction drug sildenafil has cardiopulmonary protective actions, and a nephroprotective action in cisplatin and ischemia-reperfusion- induced acute kidney injury. Here, we assessed its possible ameliorative action in a model of chronic kidney disease (CKD) using adenine feeding. Eight groups of rats were treated with saline (controls), adenine (0.25% w/w in feed daily for 5 weeks), and oral sildenafil (0.1, 0.5 or 2.5 mg/kg), either alone, or concomitantly with adenine. Urine was collected 24 h after the end of the treatments from all rats and blood pressure measured, followed by collection of blood and kidneys for the measurement of several functional, biochemical and histopathological parameters. Adenine treatment reduced body weight, creatinine renal clearance, and increased water intake and urine output, as well as the plasma concentrations of urea and creatinine, neutrophil gelatinase-associated lipocalin, and N-acetyl-beta-D-glucosaminidase activity, and albumin in urine. Adenine also increased the concentrations of the uremic toxins indoxyl sulfate, uric acid and phosphate, and a number of proteins and inflammatory cytokines, and decreased that of several anti - oxidant indices. Renal histopathological markers of damage (inflammation and fibrosis) were significantly increased by adenine. Sildenafil, given simultaneously with adenine, induced a dose - dependent improvements in most of the above parameters, suggesting its possible use as adjunct treatment for CKD in humans