43 research outputs found

    COMPARING LITERATURE REVIEW USING PRE-STUDY (QUANTITATIVE) AND POST-STUDY (QUALITATIVE) METHODS IN THE AREA OF INFORMATION GATEKEEPING BASED ON EXPLORATORY BLENDED METHOD

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    Abstract. Grounded theory method can reveal social (behavioral, cultural and environmental) factors forming the foundation of informal behaviors of the scientists in the process of science production. Literature review is recognized as a part of the grounded theory method. Discussions about how to carry out the stages of a grounded theory study have come about since 1960. During the early years, the experts had reached a consensus over the idea that the literature review should be conducted in the final stages of this methodology so that the least bias and dogmatism could occur in the creation of a theory. But, the current viewpoints are laid on the foundation that the literature review in the seminal stages of grounded theory not only does not reduce degrade the study power but it also can augment creativity, theoretical sensitivity and precision thereof. The present study compares these two perspectives within the area of information gatekeeping. The study population included the medical genetics researchers from Mashhad’s medical sciences university who were assigned to two identical groups and examined by two researchers based on pre-study and post-study. After interviewing with the researchers, two questionnaire groups, including the information gatekeeping variables extracted from the interviews, were distributed amongst the study sample volume. The results indicated a trivial difference between the two variable groups. The notable point in the result was the respondents’ easier understanding of the variables defined assisted by the post-study.Keywords: grounded theory, literature review, information gatekeeping, pre-study in grounded theory, post-study in grounded theor

    Solution of minimum spanning forest problems with reliability constraints

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    We propose the reliability constrained k-rooted minimum spanning forest, a relevant optimization problem whose aim is to find a k-rooted minimum cost forest that connects given customers to a number of supply vertices, in such a way that a minimum required reliability on each path between a customer and a supply vertex is satisfied and the cost is a minimum. The reliability of an edge is the probability that no failure occurs on that edge, whereas the reliability of a path is the product of the reliabilities of the edges in such path. The problem has relevant applications in the design of networks, in fields such as telecommunications, electricity and transports. For its solution, we propose a mixed integer linear programming model, and an adaptive large neighborhood search metaheuristic which invokes several shaking and local search operators. Extensive computational tests prove that the metaheuristic can provide good quality solutions in very short computing times

    Should State Land in Southern California Be Allocated to Warehousing Goods or Housing People? Analyzing Transportation, Climate, and Unintended Consequences of Supply Chain Solutions

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    In response to COVID-19 pandemic supply chain issues, the State of California issued Executive Order (EO) N-19-21 to use state land to increase warehousing capacity. This highlights a land-use paradox between economic and environmental goals: adding warehouse capacity increases climate pollution and traffic congestion around the ports and warehouses, while there is a deficit of affordable housing and high homeless rates in port-adjacent underserved communities. This study aims to inform regional policymakers and community stakeholders about these trade-offs by identifying current and future supply of and demand for warehousing and housing in Southern California through 2040. The study uses statistical analysis and forecasting, and evaluates across numerous scenarios the environmental impact of meeting demand for both with the Community LINE Source Model. Warehousing and housing are currently projected to be in high demand across Southern California in future decades, despite short-run adjustments in the post-pandemic period of inflation and net declines in population. Using state land for warehousing creates environmental justice concerns, as the number of air pollution hotspots increases even with electrifying trucking fleets, especially when compared against low-impact affordable housing developments. However, low-income housing demand appears to be positively correlated with unemployment, suggesting that the jobs provided by warehousing development might help to ameliorate that concern

    Efficacy of Topical Liposomal Amphotericin B versus Intralesional Meglumine Antimoniate (Glucantime) in the Treatment of Cutaneous Leishmaniasis

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    Background. Topical treatment of cutaneous leishmaniasis is an attractive alternative avoiding toxicities of parenteral therapy while being administered through a simple painless route. Recently liposomal formulations of amphotericin B have been increasingly used in the treatment of several types of leishmaniasis. Aims. The efficacy of a topical liposomal amphotericin B formulation was compared with intralesional glucantime in the treatment of cutaneous leishmaniasis. Methods. From 110 patients, the randomly selected 50 received a topical liposomal formulation of amphotericin B into each lesion, 3–7 drops twice daily, according to the lesion's size and for 8 weeks. The other group of 60 patients received intralesional glucantime injection of 1-2 mL once a week for the same period. The clinical responses and side effects of both groups were evaluated weekly during the treatment course. Results. Per-protocol analysis showed no statistically significant difference between the two groups (P = 0.317, 95% confidence interval (CI) = 1.610 (0.632–4.101)). Moreover, after intention-to-treat analysis, the same results were seen (P = 0.650, 95% CI = 0.1.91 (0.560–2.530)). Serious post treatment side effects were not observed in either group. Conclusions. Topical liposomal amphotericin B has the same efficacy as intralesional glucantime in the treatment of cutaneous leishmaniasis

    A review of grout materials in geothermal energy applications

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    Ground heat exchangers are surrounded by grout material, making it one of the most important components in geothermal energy applications since it significantly affects the system's thermal performance. The current study reviews the different types of grout materials and compares their thermophysical properties. The most critical parameter is the grout's thermal conductivity in which it always presents a proportional relation with the system's efficiency. Numerous factors are involved in this review to ascertain theier impact on the grouts’ performance such as flowability, shrinkage, moisture content, freezing, heat capacity, strength, permeability, solubility and thermal imbalance. The different grouts compared are bentonite, cement, sand, graphite, controlled low-strength material, dolomite, and phase change materials. The literature shows that phase change materials are the best choices of grouting since they can provide high storage capacity, stability and temperature uniformity. The major problem of such materials is their low thermal conductivity. Thus, it is recommended to use composite phase change materials to enhance their thermal conductivity and increase the storage/retrieval rate

    The global burden of cancer attributable to risk factors, 2010-19 : a systematic analysis for the Global Burden of Disease Study 2019

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    Background Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. Methods The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk-outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. Findings Globally, in 2019, the risk factors included in this analysis accounted for 4.45 million (95% uncertainty interval 4.01-4.94) deaths and 105 million (95.0-116) DALYs for both sexes combined, representing 44.4% (41.3-48.4) of all cancer deaths and 42.0% (39.1-45.6) of all DALYs. There were 2.88 million (2.60-3.18) risk-attributable cancer deaths in males (50.6% [47.8-54.1] of all male cancer deaths) and 1.58 million (1.36-1.84) risk-attributable cancer deaths in females (36.3% [32.5-41.3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20.4% (12.6-28.4) and DALYs by 16.8% (8.8-25.0), with the greatest percentage increase in metabolic risks (34.7% [27.9-42.8] and 33.3% [25.8-42.0]). Interpretation The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden. Copyright (C) 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

    Effects of circular corners and aspect-ratio on entropy generation due to natural convection of nanofluid flows in rectangular cavities

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    In this paper, entropy generation induced by natural convection of cu-water nanofluid in rectangular cavities with different circular corners and different aspect-ratios were numerically investigated. The governing equations were solved using a finite volume approach and the SIMPLE algorithm was used to couple the pressure and velocity fields. The results showed that the total entropy generation increased with the increase of Rayleigh number, irreversibility coefficient, aspect ratio or solid volume fraction while it decreased with the increase of the corner radius. It should be noted that the best way for minimizing entropy generation is decreasing Rayleigh number. This is the first priority for minimizing entropy generation. The other parameters such as radius, volume fraction, etc are placed on the second priority. However, Bejan number had an inverse trend compared with total entropy generation. As an exception, Bejan number and total entropy number had the same trend whenever solid volume fraction increased. Moreover, Nusselt number increased as Rayleigh number, solid volume fraction or aspect ratio increased whereas it decreases with the increase of corner radius
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