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Using abandoned gas wells as geothermal resources for energy production is an effective way to extract geothermal energy from geological formations. These abandoned wells have the potential to significantly contribute in the rising global demand for energy without requiring the land disruption resulting from deep drilling or digging, processes necessary for energy extraction from geological formations via more traditional methods. In this paper, a method to extract geothermal energy from abandoned gas wells is proposed. The method offers an efficient, economical, and environmentally-conscious way to generate electricity. A mathematical model of a thermal and hydraulic coupling process is constructed, and a 3D numerical model is generated to study the process of geothermal energy extraction by retrofitting an abandoned gas reservoir into a geothermal reservoir. Using the model, heat extraction and fluid flow are analyzed over a period of 50 years. The heat production, electricity generation, and thermal recovery over the lifetime of the reservoir indicate that a commercially viable geothermal dual well system can produce geothermal energy effectively. Dual-well systems contain at least one injection well and one production well. They are composed of a two-way flow system in which the fluid flows into the reservoir via an injection well and returns from the production well having absorbed thermal energy from the surrounding rocks. Sensitivity analysis of the main parameters controlling the average outlet temperature of the fluid from the sedimentary geothermal system reveals that abandoned gas wells are a suitable source of geothermal energy. This energy can be harvested via a method whose use of reservoir fluids differs from that of the traditional method of closed-loop circulation via a borehole heat exchanger. Here, it is demonstrated that abandoned oil and gas fields can be repurposed to be geothermal energy sources that provide low-cost electricity and are economically sustainable. [ABSTRACT FROM AUTHOR]

Adult illiteracy is a major problem worldwide especially in developing countries. Adult Basic Education (ABE) programs working in this context are not very effective due to lack of motivation for the people who are not literate. The reason is inadequate learning content and content delivery methods. This situation calls for developing novel learning content and a learner-directed content delivery approach. This paper presents an exploratory study investigating the use of the Environmental Print Material (EPM) as learning content for the non-literate population of Pakistan. The EPM content is presented to the adult non-literate population in two ethnographic studies. The most frequently recognized content is selected and utilized as learning content in a Computer Assisted Learning (CAL) application. An empirical study is conducted upon two groups with 107 participants to compare the EPM-based learning content with Traditional Learning Content (TLC). As many as 54 participants participated in the experimental group (presented with EPM-based learning content), whereas 53 participants took part in the control group (presented with TLC content). The results reveal that the experimental group performed significantly better compared to the control group in recognition, pronunciation, and recall of the presented content. The meta-analysis of the results shows a large effect size of (1.05) with confidence interval in the range (0.798–1.315). The results claim that the EPM has potential to be considered as learning content in the ABE programs. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to build and assess the performance of survival prediction models using the gender-specific informative risk factors for patients with left ventricular systolic dysfunction. Methods: A lasso approach was used to decide the informative predictors for building semi-parametric proportional hazards Cox model. Separate models were built for all patients [N = 299], male patients [Nmale = 194 (64.88%)], and female patients [Nfemale = 105 (35.12%)], to observe the risk factors associated with the individual’s risk of death. The likelihood- ratio test was used to test the goodness of fit of the selected model, and the C-index was used to assess the predictive performance of the selected model(s) with respect to the overall model with all observed risk factors. Results: The survival prediction model for females is notably different from that for males. For males, smoking, diabetes, and anaemia, whereas for females, ejection fraction, sodium, and platelets count are non-informative with zero regression coefficients. The goodness of fit of the selected models with respect to the general model with all observed risk factors is tested using the likelihood-ratio test. The results are in favor of the selected models with p-values 0.51,0.61, and 0.70 for all patients, male patients, and female patients, respectively. The same values of C-index for the full model and the selected models for overall data, for males, and for females (0.72, 0.73, and 0.77 for overall data, male data, and female data, respectively) indicate that the selected models are as good as the corresponding overall models regarding their predictive performance. Conclusion: There is a substantial difference in the survival prediction models for heart failure (HF) of male and female patients in this study. More studies are needed in Pakistan for confirming this striking male-female difference regarding the potential risk factors to predict survival with heart failure. [ABSTRACT FROM AUTHOR]

Background and objectives: Practice-based research (PBR) is of pivotal importance for hospital pharmacists which not only up-grades the profession but also improves the patient care. This study aimed to evaluate the attitude, perception, willingness, motivation and barriers to PBR among hospital pharmacists in Pakistan. Methods: A descriptive, cross sectional study design was employed. Data were collected between 1st December, 2017 and 1st March, 2018 from 130 hospital pharmacists employed in 41 hospitals of Lahore, Pakistan. A survey instrument comprising of six sections was designed to determine the attitude, perception, willingness, motivation and barriers to PBR. Data were analyzed by using Statistical Package for Social Sciences (IBM SPSS Statistics for Windows, version 21.0, Armonk, NY: IBM Corp.). The normality of the data was determined through Shapiro-Wilks and Kolmogorov-Smirnov tests. Independent Samples Mann-Whitney U Test and Independent Samples Kruskal-Wallis Test were carried out to test if there were differences among the characteristics of the hospital pharmacists. Logistic regression analysis was used to figure out the factors associated with attitude, perceptions, willingness and motivation towards PBR. A p-value <0.05 was used for statistical significance of differences. Results: A total of 141 pharmacists were approached. Among them, 130 responded to the survey (response rate 92%). Out of a maximum score i.e., 5 (100%) the respondents obtained a median score of 4 (IQR = 0) for attitude, perception and motivation towards PBR; whereas, a median score of 4 (IQR = 1) was obtained for willingness thus demonstrating fair positive attitude, good perceptions, increased motivation and willingness towards PBR. The most common barrier limiting the pharmacists’ participation in PBR was lack of time (23.8%) followed by lack of incentives (16.2%) and lack of support (14.6%). Results of the logistic regression analysis revealed that hospital pharmacists practicing in the inpatient settings had 4.56 times more positive attitude towards PBR (OR = 4.56, 95%CI = 1.07─19.42, p-value = 0.040) as compared to those practicing in the outpatient settings. The male hospital pharmacists (OR = 8.86, 95%CI = 1.15–53.74, p-value = 0.017), those practicing in the outpatient (OR = 23.51, 95%CI = 2.04─271.53, p-value = 0.011) and inpatient settings had increased motivation towards PBR (OR = 12.24, 95%CI = 1.61─94.66, p-value = 0.016). Conclusion: Despite the presence of several barriers, the respondents had fair positive attitude, good perceptions, increased motivation and willingness towards PBR which is a promising finding. [ABSTRACT FROM AUTHOR]