Assessment of the Recycled Concrete Aggregates Structural Suitability for Road Construction

In most aspects of modem life, there is a consensus among practitioners and decision makers of the importance of preserving the environment, and to find alternatives to the scarce natural materials. This can be accomplished by better utilization of the natural materials and/or recycling or reclaiming their waste, specially, if they are of finite resources. The recycled material could be an attractive alternative (both environmentally and economically) if its characteristics are proven to be close to those of the natural material. Utilizing recycled mineral aggregates in the construction field in general and in highway pavement in specific is somehow governed by its ability to meet its intended function as carrying component within the structure. In the area of pavement construction, the suitability of the recycled aggregates is primarily judged by its ability to carry the high traffic loads effectively. The primary objective of this thesis is to study the suitability of using the Recycled Concrete Aggregates (RCA) for pavement construction or rehabilitation. The RCA is intended to replace the virgin material in one of the pavement layers, namely the subabse. The general characteristics of the RCA material (such as the grade distribution) are compared against the subbase material specifications. A testing model is built to quantify the RCA-layered pavement performance under various load levels, and to comparatively assess its behavior against the virgin mineral aggregates. The model dimensions are set large enough to replicate the pavement structures in reality to ensure accurate analysis. Several experimental settings are considered to account for the possible variability in the pavement loads (generated by the various vehicle types), material gradation, composition and thickness. The performance of the RCA material is captured through the resulting load-deflection relationships of the various settings. The results of these experiments indicated the good potential of the RCA as a subbase material. The resulting load-deflection relationships of both the RCA- and virgin-materials indicated the superiority of the RCA-material as a subbase material. In general the deflection results of the experiments indicated that the pavement deflection under load is generally lesser with the RCA material

Nanoparticles and Surfactants-Stabilized Foam and Emulsion for Gas Mobility Control in Petroleum Reservoirs

This work proposes the use of nanoparticles (NPs) to stabilize foams/emulsions for gas mobility control and to improve the gas sweep efficiency. First, NPs were used alone to stabilize emulsion. Second, NPs and surfactants were used synergistically to improve the stability of foam. Surface modified silica NPs with DCDMS, hidden chemical, and PEG were used to assess the ability of NPs to stabilize gas-liquid emulsions at reservoir conditions. Silica modified with DCDMS was able to increase the CO2 viscosity 26-60 fold. Silica modified with hidden chemical was able to increase the CO2 viscosity 25-53 fold and N2 viscosity 22-54 fold. Finally, the presence of silica modified with PEG was able to increase the CO2 viscosity 24-49 fold. All tested materials showed an inverse relationship between the emulsion quality and viscosity. In most cases, salinity was found to have a significant impact on emulsion strength. As salinity increased, the emulsion viscosity increased, too. The concentration of NPs showed similar behavior, with NPs concentration and viscosity being directly proportional. Shear rate was found to be a crucial parameter for emulsion stability and viscosity, with a threshold shear rate being necessary to stabilize emulsions. Also, increased pressure can improve emulsion stability to produce a more viscous emulsion. The presence of NPs in all surfactant solutions enhanced foam stability and produced more viscous foams compared to surfactant alone. The presence of NPs with ENORDET A031 was able to increase the gas MRF up to 84.57 compared to 72.57 for surfactant. For the mixtures of silica NPs and nonionic surfactants, results showed that the concentration of surfactant and NPs is a crucial parameter for foam stability and that there is an optimum concentration for strong foam production. For N2 foam, the mixture of surface modified silica NPs and CNF surfactant resulted in a total recovery of 49.05% compared to 41.45% for surfactant alone. The total oil recovery for the same mixture with sc-CO2 was 80.05% of the OOIP. This is around 4% higher than the surfactant case and 8.55% higher than sc-CO2. In fractured rocks, oil recoveries during secondary production mechanisms for the mixture of surface modified silica NPs and CNF surfactant, the surfactant alone, and sc-CO2 alone were 12.62, 8.41 and 7.21% of the OOIP, respectively

Bilateral inverted and impacted maxillary third molars: a case report

Bilateral inverted third molar impaction is an extremely rare condition. We reported the case of a 50-year-old female patient with bilateral inverted and impacted maxillary third molars. Both were asymptomatic and pathology free clinically and radiographically. Surgical extraction of these inverted third molars with inaccessible positions requires an aggressive bone removal on the tuberosity bilaterally. Moreover, it contains a high risk of displacement of the inverted third molar into the maxillary sinus. Conservative management was the choice, with the patient’s agreement, and the inverted third molars were left in sit

Campylobacteriosis in New Zealand: Causes and control : A thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University

New Zealand (NZ) has a higher rate of reported campylobacteriosis cases than the rest of the developed world. The majority of human campylobacteriosis cases are attributable to the consumption of poultry products. The hypotheses explored in this study are: (i) NZ C. jejuni strains have a greater heat tolerance and hence are better able to survive cooking, (ii) NZ strains are more oxygen tolerant, (iii) secondary poultry processing practices increase the NZ chicken contamination with Campylobacter (iv) Food preparation home hygiene practices in NZ are poor compared with the developed world. Quantitative microbial risk assessment (QMRA) was carried out by applying an advanced Bayesian approach to assess all the factors in the food chain, which impact the final campylobacteriosis risk estimation. Moreover, the current intervention practices applied at the poultry plant was investigated to find a better physical intervention method than the potential unsafe chemical intervention processes applied currently. Finally, an alternative approach to QMRA that could predict more accurately the annual campylobacteriosis risk in NZ was also investigated. The kinetic parameters (D and z values) determined under the isothermal and dynamic condition in broths culture or on chicken skin for the most implicated strains in human campylobacteriosis cases in New Zealand were broadly in agreement with published international data. They did not indicate that NZ strains (ST 474, ST 190, ST 48, ST 45 from humans and poultry) were more heat resistant than the overseas strains. Similarly, the bacterial survival under oxidative stress showed that the oxygen tolerance of NZ strains was also similar to other internationally reported strains. A secondary practice (marination of chicken by needle injection) investigated at a poultry production plant did not significantly increase the chicken carcasses contamination level. The results confirm that the tested New Zealand C. jejuni strains do not have unusual characteristics, and the high rate of campylobacteriosis in New Zealand is not associated with the emergence of more environmental stress-resistant strains. This finding has a significant impact on the poultry industry, regulators, consumers and researchers as it confirms the scientific evidence to maintain the stipulated standards for the heat treatment practices at poultry plants, food services and at homes. Changes to heat treatment practices can cause unpredicted loss to the poultry industry. It is important for the regulatory bodies to convey to all consumers, the critical message of the cooking temperature given the reluctance of NZ consumers to use food thermometers to verify the home cooking temperatures. The results of the consumers' food handling practices survey revealed that the mean score of food safety practices and food safety awareness of the New Zealanders who participated in the survey was below the average questionnaire score of 10.5 out of 21 (the total score ). The study confirmed that the awareness of basic food hygiene and safe food preparation practised by people in New Zealander was lower than in other developed countries. Therefore, an innovative and more effective approach needs to be implemented for future consumer education strategy. The QMRA conducted in this study indicated that hygiene has a significant impact on total illness probability. The 'Bayesian hierarchal model', which provides a better insight into the food chain than the 'time series model' and is more informative as it incorporates all the factors that impact on the final risk estimation. The QMRA model was able to identify the consumer hygiene practices, the initial contamination prevalence at the farm and the practices at the processing plant, as the significant factors influencing the final risk estimate. The association between the reduction in birds/chicken carcases prevalence and improvement in home hygiene practice and the calculated reduction in risk of human disease was estimated to be 1:1, which agrees with international findings. Thus, QMRA model can easily determine the impact of any intervention in the food chain. Therefore, the effect of a new planned intervention such as consumer education on the final risk estimate should be clear for the policymakers, risk managers and health professionals. This can be achieved by altering the priors of the consumer hygiene practices in QMRA model. Similarly, other interventions at poultry plants and farms should also be assessed by altering the priors of farms and poultry plants. The Bayesian hierarchal model, which has been used in this study, was able to deliver the expected outcomes and to provide a fast response for policymakers and risk managers. The Auto-Regressive Integrated Moving Average (ARIMA) with an intervention model provided one of the best prediction of the annual campylobacteriosis risk in NZ from the ten models tested. ARIMA intervention model has the lowest forecast error with, only 9 % campylobacteriosis cases more than the actual notified cases. The Holt-Winters method, being local in nature, quickly adapts to the new post-intervention regime and also gives a good prediction which is comparable with the ARIMA intervention models. This method has the additional advantage that it is simple to calculate. This study also highlighted the potential alternative physical interventions such as the immersion in hot water or hot water wash at poultry processing plants that could be employed with possible another physical intervention in case a ban on chemicals that are currently used to control campylobacteriosis is imposed in NZ

A Review of Enzymatic Transesterification of Microalgal Oil-Based Biodiesel Using Supercritical Technology

Biodiesel is considered a promising replacement to petroleum-derived diesel. Using oils extracted from agricultural crops competes with their use as food and cannot realistically satisfy the global demand of diesel-fuel requirements. On the other hand, microalgae, which have a much higher oil yield per hectare, compared to oil crops, appear to be a source that has the potential to completely replace fossil diesel. Microalgae oil extraction is a major step in the overall biodiesel production process. Recently, supercritical carbon dioxide (SC-CO2) has been proposed to replace conventional solvent extraction techniques because it is nontoxic, nonhazardous, chemically stable, and inexpensive. It uses environmentally acceptable solvent, which can easily be separated from the products. In addition, the use of SC-CO2 as a reaction media has also been proposed to eliminate the inhibition limitations that encounter biodiesel production reaction using immobilized enzyme as a catalyst. Furthermore, using SC-CO2 allows easy separation of the product. In this paper, conventional biodiesel production with first generation feedstock, using chemical catalysts and solvent-extraction, is compared to new technologies with an emphasis on using microalgae, immobilized lipase, and SC-CO2 as an extraction solvent and reaction media

The effect of atypical antipsychotics on platelet aggregation

ABSTRAC

What is the Way Allah's Word Manifests Itself in Yemeni Arabic?

In this paper, the author shows how ‘Allah’ is used in daily Yemeni Arabic conversations. The term Allah has a variety of meanings in Yemeni Arabic, as it does in the Arab world, reflecting the belief that Allah alone is in charge of all the affairs, grants blessings, and either encourages or criticizes someone to do something. The result of this is that the term Allah appears in several expressions when the term is part of a sentence containing the word. For example, there are expressions that have over one meaning, such as Allah alaik, which signifies two literal meanings. The word Allah can also be found in other expressions, but with entirely different meanings, including moaning or aiming for guidance. I conducted a study looking at the occurrences of social life contact, reactions, and the cultural influence of native Yemenis. The rest of this paper explores some of the other most common expressions used in Yemeni society, which shows the word is heavily influenced by religion and culture in its use in Yemeni society

A framework for pronunciation error detection and correction for non-native Arab speakers of English language

This paper examines speakers’ systematic errors while speaking English as a foreign language (EFL) among students in Arab countries with the purpose of automatically recognizing and correcting mispronunciations using speech recognition, phonological features, and machine learning. Accordingly, three main steps are implemented towards this purpose: identifying the most frequently wrongly pronounced phonemes by Arab students, analyzing the systematic errors these students make in doing so, and developing a framework that can aid the detection and correction of these pronunciation errors. The proposed automatic detection and correction framework used the collected and labeled data to construct a customized acoustic model to identify and correct incorrect phonemes. Based on the trained data, the language model is then used to recognize the words. The final step includes construction samples of both correct and incorrect pronunciation in the phonemes model and then using machine learning to identify and correct the errors. The results showed that one of the main causes of such errors was the confusion that leads to wrongly utilizing a given sound in place of another. The automatic framework identified and corrected 98.2% of the errors committed by the students using a decision tree classifier. The decision tree classifier achieved the best recognition results compared to the five classifiers used for this purpose

Predictors of Non-adherence in Patients Taking Psychotropic Medication and Suggestions to Improve

Background: Non-adherence to treatment, especially medication is an important area of concern in psychiatry as it contributes to relapse and re-hospitalization of the patients. One of the ways to improve drug adherence is to know crucial factors responsible for poor medication adherence so that proper management strategies may be planned to improve patients’ drug adherence. This article reviews the literature of non-adherence, discusses patients’ reasons for failure to concord with medical advice, elect the predictors of and solutions to the problem of non-adherence. Aims: To discuss the aspects of medication adherence and definition about health behavior and it will examine the predictors of non-adherence in those taking psychotropic medication and provide the physicians with various strategies for improving medication adherence among their patients. Methods: We conducted a MEDLINE database literature search and science direct database were undertaken, limited to English language articles published between 1993 and 2014, using the following search terms: adherence, non-adherence, compliance, Improve medication adherence, strategies for physicians and pharmacists to ensure medication adherence, pharmacotherapy. Conclusion: Medication non-adherence was significantly associated with an increased risk of rehospitalization, emergency room visits, homelessness and symptoms exacerbation. Non-adherence was significantly more likely to have a history of medication non-adherence, substance abuse or dependence, and difficulty recognizing her own symptoms. Patients who became medication non-adherence were significantly less likely to have a good therapeutic alliance form during hospitalization and were more likely to have family members who refused to become involved in their treatment. Community psychiatric services can potentially use effective clinical interventions, approved by scientific evidence, for reducing patient non-adherence. Strategies for adherence include raising information and skill levels, altering characteristics of the regimen, and improving the relationship between the provider and the patient. Provider and the patient awareness with regard to medication adherence can be enhanced with the creative application of behavioral contracts. Adherence promoting efforts can also include rewards and improvement strategies