Upgrading Biological Treatment of Wastewater at Dubai’s Plant by a Fixed-Film System

The wastewater treatment plant in Dubai, with a design capacity of 130,000 m3/d, receives primarily domestic wastewater and employs primary, secondary and tertiary stages of treatment to produce an effluent suitable for reuse in irrigation. Performance of the plant is influenced to a great extent by the success of the secondary aerobic biological treatment stage. This stage comprises the high-rate activated sludge system for removal of carbonaceous organics followed by the biofilter system for removal of nitrogenous material by nitrification. Operational problems have often been experienced at this plant because of increasing sludge solids production and sludge rising in the high-rate activated sludge system, which in turn overload the sludge treatment facilities and the biological filter system. This study aimed at upgrading the existing biological treatment system in an attempt to improve process performance and overcome operational problems. An innovative biological system, the aerated submerged fixed-film (ASFF) process which employs a four compartment-in-series reactor with an array of fixed ceramic plates, has been examined for this purpose. The study involved field testing and chemical analyses of a pilot-scale ASFF bioreactor in a series of experiments on the ASFF reactor in parallel with the existing activated sludge and biofilter systems. Performance of the ASFF process was examined at different hydraulic retention times (HRT\u27s) and loading conditions. The results obtained demonstrated the feasibility of upgrading the existing facilities by the ASFF process. Analysis of performance data indicated comparable results at short HRT\u27s of 2 hours and considerably better results from the ASFF at longer HRT\u27s of 6-8 hours. The ASFF process has an advantage of combining the removal of both carbonaceous and nitrogenous materials in one system rather than in two systems as practiced in the existing facilities. This process requires less space and produces minimal sludge solids quantities, thus reducing the treatment costs. It will provide an adequate treatment that does not suffer from the rising sludge problem and can easily cope with overloading as long as sufficient aeration is provided. The process can be easily implemented in the aeration tanks of the existing activated-sludge system by fixing an array of locally-made ceramic plates which will also eliminate the need for biofilters. A mathematical model was adopted to describe process kinetics and to design the upgraded system

STUDY THE QUALITY OF GROUNDWATER OF AL-ZOROUP AREA IN MAHDAH STATE, THE SULTANATE OF OMAN

The groundwater is the most important source of water in the Sultanate of Oman. Accordingly, the Oman Government has paid great attention commensurate with the importance of water resource in terms of their sources, quality, and ways to rationalize consumption to remain under the term of sustainability and validity of present and future generations. This study was conducted in Al Buraymi at Mahdah State in Al-Zoroub area targete a groundwater quality for 20 wells in private farms. The water samples were taken from these wells and subjected to analysis for microbial and geochemical aspects. For this analysis, the assorted devices and instruments were implemented. Additionally, to focus on the possible sources of pollution and the range of competence for the human user or livestock and agriculture of this water, the international guideline measures were used for compression. Based on investigations from a group of chemical and biological analysis; it turns out that this water contained varying proportions of salts and dissolved minerals. These results also build on the proportions of dissolved salts which showed different types of water in these wells which are mostly fresh (magnesium bicarbonate) in ten wells, brackish (magnesium chloride) in six wells and saline (sodium chloride) in four wells. The dominant water type (magnesium bicarbonate) resulted from the fresh water in the upper aquifer, which recharged from northeastern catchment areas of Mahadah, Wadi Al Jizi, and Wadi Hamad. Moreover, it was found that the abundance of the major cation ions in groundwater is in the following order: Na+ \u3e Mg2+\u3e Ca2+\u3e K+, where as the abundance of the major anion ions in groundwater is in the following order: Cl-\u3e HCO3-\u3e SO4-\u3e NO3.- These distribution is ffected by salinization phenomena (ion exchange), mixing of saline water in the deep aquifer with fresh water and by anthropogenic sources. The building at the expense of sodium adsorption ratio (SAR) found that 65% of the wells are located within the category of hazardous water at least for sodium ion and vii medium salinity rate. So they are safe for agricultural use except for well no (8) located in the category of high salinity. On the other hand, the results showed microbial water containing high levels of coliform bacteria and E.coli species in nine wells. Compared to WHO guidelines, not all 20 wells that I have investigated are suitable for human use without treatment, and 70% of them are not suitable for animal use, but in contrast, all wells are suitable for agricultural use. During the term of microbial source tracking method (MST) that applied on 9 Escherichia coli (E.coli) samples used 16SrRNA, which blasted in the NCBI; sequences of these samples were identified by comparison with the GenBank database used BLAST searches. It was found that all isolated E.coli were homologous with isolated single E coli species (E.coli K-12 substr - MG 1655 strain) which first identified in the faeces of human. According to filed survey and investigation, the main cause of E. Cole in the groundwater is may be septic tank and animal manure, which is very close to these wells, or the well heads are not completely sealed, which would allow contaminants to enter the well

Agricultural Land Expansion and Food Security in Pakistan: An Empirical Analysis

This study empirically investigates the impact of agricultural land, urbanization, GDP, food import, and credit to the agricultural sector on food security in Pakistan. The study employs Auto Regressive Distributive Lag Model (ARDL) bound testing procedure to estimate the impact of these factors on food security from the period1990 to 2016. Following the literature, we have employed two dimensions of food security: food availability and food accessibility. Food availability is measured by food supply (kcal/capita/day) while food accessibility is measured by food price indices. The results indicate that agricultural land, GDP growth, and credit to the agricultural sector have a positive and an increase in urban population has a negative impact on both dimensions of food security however, food imports have a positive impact on food availability and a negative on food accessibility in the country

Examining the extent of and drivers for materiality assessment disclosures in sustainability reports

Purpose: This paper aims to evaluate the extent of materiality assessment disclosures in sustainability reports and their determinants. The study examines the disclosure practices of listed companies based in the member states of the Cooperation Council for the Arab States of the Gulf, colloquially referred to as the Gulf Cooperation Council (GCC). Design/methodology/approach: First, the materiality assessment disclosures were scored through a content analysis of sustainability reports published by listed GCC companies during a five-year period from 2013 to 2017. Second, a fixed effect ordered logic regression was used to examine the determinants of materiality assessment disclosures. Findings: While sustainability reporting rates improved across the sample period, a significant majority of listed GCC companies do not engage in sustainability reporting. The use of internationally recognised standards has also declined. While reporters provide more information on their materiality assessment, the number of sustainability reports that offer information on how the reporter identifies material issues has declined. These trends potentially indicate the existence of managerial capture. Materiality assessment disclosure scores are positively influenced by higher financial performance (Return on Assets), lower leverage and better corporate governance. However, company size and market-to-book ratio do not influence materiality assessment disclosures. Practical implications: The findings may prove useful to managers responsible for preparing sustainability reports who can benefit from the examples of materiality assessment disclosures. An evaluation of the materiality assessment should be included in the scope of assurance engagements and practitioners can use the examples of best practice when evaluating sustainability reports. Stock exchanges may consider developing improved corporate governance guidelines as these will lead to materiality assessment disclosures. Social implications: The findings may assist in improving sustainability reporting quality, through better materiality assessment disclosures. This will allow corporate stakeholders to evaluate the reporting entities underlying processes, which leads to transparency and corporate accountability. Improved corporate sustainability reporting supports the GCC commitment to implement the United Nations Sustainable Development Goals and transition to sustainable development. Originality/value: This study addresses the call for greater research examining materiality within a sustainability reporting context. This is the first paper to examine sustainability reporting quality in the GCC region, focussing particularly on materiality assessment disclosures

Infected non-union of tibia treated with ilizarov external fixator: Our experience

Introduction: Tibia is the most common long bone fractured due its vulnerable subcutaneous location and most often associated with acquired complications of delayed union or non-union due to infection. Amongst the various treatment options to treat them, the Ilizarov external fixator application is considered superior due to its multiple advantages. The objective of this study was to analyse the role of Ilizarov fixation in infected tibial non-union, as well as to assess bony union and associated functional outcomes. Materials and Methods: A retrospective review was conducted for the duration between 1st January 2005 to 31st December 2016. Total of fifty-one patients with tibial non-union associated with infection who treated with the Ilizarov fixator were included in the study. Patient records were reviewed for union of bone, bone and functional outcomes and complications. Results: The most common organism for infection was identified to be Staphylococcus Aureus. At the time of final follow-up all patients had achieved union except two, one of whom had to undergo amputation due to non-union and sepsis. Majority of the patients had an excellent score as per ASAMI grading system for bone and function results. The most common complication noted was pin track infections. Conclusion: In our experience, Ilizarov external fixator is better suited for infected non-union of tibia because it can provide a stable mechanical environment, bone transport, correct deformities, and enable weight bearing and hence we recommend its use for the same

Ankle arthrodesis using Ilizarov ring fixator: A primary or salvage procedure?: An analysis of twenty cases

Introduction: Ankle arthrodesis using the Ilizarov technique provides high union rate with the added benefits of early weight-bearing, and the unique advantage of its ability to promote regeneration of soft tissue around the bone, including skin, muscle and neuro-vascular structures, and its versatility to allow correction of the position of the foot by adjusting the frame post-operatively as needed. We describe our experience with this technique and the functional outcomes in our patients. Materials and Methods: This retrospective study was conducted in 20 ankle fusion cases using the Ilizarov method between the years 2007 and 2017. We defined success in treatment by loss of preoperative symptoms and radiological union on plain radiographs of the ankle. Results: Fusion was achieved in all patients (100%). Immediate post-operative ambulation was with full weight bearing (FWB) in 16 (83%) of the participants and non-weight bearing (NWB) in 3 patients (17%). Post-procedure 11 patients (67%) of the participants who were full weight bearing required some form of support for walking for 2-3 weeks. Post-operatively three patients had pin tract infection requiring intravenous antibiotics. Radiological union took range of 6-12 weeks, mean union time was 8 weeks. Only one patient required bone grafting due to bone loss. Average follow-up period was 10-45 months. Conclusion:The Ilizarov technique has a high union rate and leads to general favourable clinical outcome and may be considered for any ankle arthrodesis but is especially useful in complex cases such as for revisions, soft-tissue compromise, infection and in patients with risk for non-union. Early weight bearing is an extra benefit

Moment Generating Functions of Complementary Exponential-Geometric Distribution Based on k-th Lower Record Values

The complementary exponential-geometric (CEG) distribution is a useful model for analyzing lifetime data. For this distribution, some recurrence relations satisfied by marginal and joint moment generating functions of k-th lower record values were established. They enable the computation of the means, variances, and covariances of k-th lower record values for all sample sizes in a simple and efficient recursive manner. Means, variances, and covariances of lower record values were tabulated from samples of sizes up to 10 for various values of the parameters

A qualitative study on violent extremists and news media : how Malaysian online news framed violent extremist groups involved in the Syrian civil war

e news has been a place for violent extremist groups to gain recognition internationally. The Syrian Civil war which had involved notorious and internationally recognised violent extremist groups is an example of this phenomenon. However, a limited number of studies had uncovered the thematic variation on how Malaysian online news frames violent extremist groups involved in the Syrian Civil War. Therefore, the present study explored whether the Malaysian news coverage of the violent conflicts that involved violent extremist groups active during the Syrian civil war may shed light on how mainstream news covers violent extremist groups. The present study employed a qualitative search and analysis of two popular online newspapers in Malaysia to identify the types of news frames on the news published during the peak of the Syrian civil war and when a notorious violent extremist group, Daesh (alternatively known as Islamic State (IS) or Islamic State of Iraq and Syria (ISIS)), had shaken and threatened the world. A total of 272 news articles published between 2010 to 2020 were collected and analyzed. Analysis of the news frames revealed twelve different news frames. The frame with the highest occurrence was labelled as “Western destructive interventions”. The frame detailed out Western nations’ involvement in the war which caused damage to livelihood and civilizations in Syria and justified the violent extremist groups’ activities. The present study concludes that the Malaysian news media framing on violent extremist groups and other parties involved in the Syrian Civil War could have two varied forms, positive (heroic or humanized) or negative (destructive or demonized). The main contribution of this study is that it provides an insight into how Malaysian news media cover a conflict involving Muslim extremist groups. Additionally, the study adds to previous research on how violent extremist groups is framed in digital news

CYTOCHROME P450 CYP1B1*2 GENE AND ITS ASSOCIATION WITH T2D IN TABUK POPULATION, NORTHWESTERN REGION OF SAUDI ARABIA

Objective: Cytochrome P450 1B1 (CYP1B1) is involved in the activation of procarcinogens and steroid metabolism. Genetic variants of CYP1B1are associated with altered catalytic activity and disease phenotypes. The purpose of this study was to investigate the role of CYP1B1 (rs1056827) polymorphism in inducing T2D.Methods: This cross-sectional study enrolled 113 subjects of T2D and 120 controls. DNA was isolated from blood. Genotyping of the rs1056827 wasdone by allele-specific polymerase chain reaction. The frequency of alleles and genotype distribution was compared in T2D cases and healthy controls.Statistical analysis was performed with SPSS, Chi-square, and Fisher exact test. Hardy-Weinberg equilibrium was tested by a χ2 test. The associations between rs1056827 variant genotypes and T2D were estimated by computing the odds ratios and their 95% confidence intervals (CI) from univariate and multivariate logistic regression analysis.Results: A significant association of rs1056827 was found between T2D cases and controls (p<0.0001). When GG genotype was compared with GT genotype a significant association was found with odd ration (OD)0.24 (95% CI: (0.131–0.452) and risk ratio (RR) 0.45 (0.30–0.67) times the risk of T2D heterozygous with the G/T allele (p≤0.0002). In a comparison of GG homozygous with the TT homozygous, there was no significant association with the OD 0.38 (95% CI: (0.02–6.51) RR 0.55(0.13–2.35), p<0.49. When G allele was compared with the T allele a highly significant association with OD 0.54 (95% [CI]: (0.37–0.80) RR 0.75(0.630–0.897) < p≤0.003 suggesting a possible dominant effect of this polymorphism on T2D risk.Conclusion: This result suggests a significant association between rs1056827G>T polymorphism and T2D. This finding is limited due to the smaller sample size and can be validated by large sample size studies

Frequency of intraoperative hypotension after the induction of anesthesia in hypertensive patients with preoperative angiotensin-converting enzyme inhibitors

Introduction: The renin-angiotensin-aldosterone system (RAAS) is an important target in the treatment of hypertension. Angiotensin-converting enzyme (ACE) inhibitors block the conversion of angiotensin I to angiotensin II. ACE inhibitors not only treat hypertension but also decrease morbidity and mortality in heart failure patients and in patients with acute myocardial infarction. The discontinuation of ACE inhibitors before the surgery is still controversial. To assess the current magnitude of the problem in our population, we aimed to conduct this study, which evaluated the frequency of intraoperative hypotension after the induction of anesthesia in controlled hypertensive patients with preoperative ACE inhibitors.Material and methods: This descriptive case series study was conducted at a tertiary hospital in a developing country after approval from the Ethics Review Committee. A total of 115 adult patients, from 16 to 60 years of age, who have undergone elective surgery, have controlled hypertension on the desired drugs for at least six months, have no history of any cardiac event, and have taken the drug on the morning of the surgery, were included in the study after written consent. The demographic data of the patients were entered into the proforma. Preoperative systolic, diastolic, and mean arterial pressure were recorded by the researcher or an assignee in the preoperative holding area. The patients were followed in the recovery room by the team conducting the study until 10 minutes after the arrival of the patient in the recovery room. All statistical analyses were performed using Statistical Packages for the Social Sciences version 19 (SPSS Inc., Chicago, IL). p-value ≤0.05 was considered significant.Results: Of the 115 patients, 56 (48.7%) patients were in the age group between 51 and 60 years of age; 38 patients were between the ages of 41 and 50 years and only 21 patients were 40 years or less. On gender, 68 patients were female and 47 were male. According to body mass index (BMI), the majority of the patients were in the overweight group, amounting to 53 (46%), and 86 (74.78%) patients were known diabetics. Overall, 77 (66.96%) of the patients developed intraoperative hypotension with 41 (35.65%) patients requiring the use of vasopressors in order to correct the hypotension. No statistically significant difference was found between demographic and clinical variables.Conclusion: Intraoperative hypotension is more frequent in patients with controlled hypertension on ACE inhibitors although more studies need to be conducted on a larger population in order to determine a more definitive result