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Comparative Analysis of MCDM Methods for the Assessment of Corporate Sustainability Performance in Energy Sector
No full textEnergy is a significant input for production, growth, and development. A sustainable energy sector, where energy production and consumption balance are ensured, constitutes a key point for nature and humanity. In this study, a multidimensional framework is presented to measure corporate sustainability in the energy sector. Based on this framework, the sustainability performance of energy companies operating in the Asia and Europe regions is measured by hybrid multiple-criteria decision-making (MCDM) methods, considering the economic, social and environmental dimensions of sustainability. The Entropy method is preferred to specify the criteria weights, the Proximity Indexed Value (PIV) -Range of Value (ROV) -Grey relational analysis (GRA) -Measurement Alternatives and Ranking according to Compromise Solution (MARCOS) methods are used to rank the alternatives. Sensitivity analysis was applied to test the robustness of the model and it was determined that the criterion weights obtained by different methods had different effects on the rankings. The Copeland method is used to obtain a single rational ranking from different rankings. According to Copeland's results, EN13, EN3, EN10 companies took the first place in economic, environmental and social dimensions, respectively. It is concluded that energy companies in the Asian region are more sustainable than in the European region. Moreover, Thailand is the most sustainable country in the Asian region. The proposed framework can be contributed to the development of the energy sector
Multiple Brain Tumor Classification with Dense CNN Architecture Using Brain MRI Images
No full textBrain MR images are the most suitable method for detecting chronic nerve diseases such as brain tumors, strokes, dementia, and multiple sclerosis. They are also used as the most sensitive method in evaluating diseases of the pituitary gland, brain vessels, eye, and inner ear organs. Many medical image analysis methods based on deep learning techniques have been proposed for health monitoring and diagnosis from brain MRI images. CNNs (Convolutional Neural Networks) are a sub-branch of deep learning and are often used to analyze visual information. Common uses include image and video recognition, suggestive systems, image classification, medical image analysis, and natural language processing. In this study, a new modular deep learning model was created to retain the existing advantages of known transfer learning methods (DenseNet, VGG16, and basic CNN architectures) in the classification process of MR images and eliminate their disadvantages. Open-source brain tumor images taken from the Kaggle database were used. For the training of the model, two types of splitting were utilized. First, 80% of the MRI image dataset was used in the training phase and 20% in the testing phase. Secondly, 10-fold cross-validation was used. When the proposed deep learning model and other known transfer learning methods were tested on the same MRI dataset, an improvement in classification performance was obtained, but an increase in processing time was observed
Mid to late Holocene water level and inferred climate changes of Lake Salda (SW Anatolia/Turkey): evidence from high-resolution seismic and sediment-core records
No full textThe sedimentary sequence in Lake Salda has been first documented in detail by analyses of high-resolution seismic profiles and sediment cores together with onshore outcrops along the present shoreline of the lake. Such a multi-proxy approach provides a strong record of changing lake levels and depositional conditions in Lake Salda during the mid to late Holocene. The accurate determination of water-level oscillation and climate conditions relies on the confident deduction from 14C-dated onshore outcrops and sediment cores, which provide calibration for the chronostratigraphic units within high-resolution seismic records. The existence of a dry climate period during the transition from the middle to late Holocene caused the lake level to decrease until 1690 cal years BP. This prominent climate deterioration induced coastal progradation in the lake as inferred from the deltaic sequences in the high-resolution seismic record and favored stromatolite formation, given its oligotrophic water condition. The resultant lowstand of lake level during the late Holocene timely coincided with the Roman Climatic Optimum when a prominent erosional truncation surface and channel incision were formed as observed from the seismic profiles. The late Holocene, during 1690–1050 cal years BP, is represented by a transgressive condition due to lake-level increase, giving rise to a retreat of the deltaic deposit further inland. The ongoing deepening of the lake by contributions of both climate and tectonic activity during the last 650 cal years BP produced Gilbert-type fan deltas along the shoreline and a transgressive sedimentary unit with typical onlapping architecture in the seismic reflection profiles
Assessment of Endoscopy Fear: a Survey Study at a Major Tertiary Hospital
No full textObjective: In this survey, we attempted to reveal the incidence and reasons of fear and anxiety caused by endoscopic procedures in patients who will have upper gastrointestinal endoscopy, which is more common in this population. Methodos: The study included adult patients who had an upper gastrointestinal endoscopic appointment in the General Surgery Endoscopy Laboratory. The study participants were asked to read and complete two questionnaires while being observed in the endoscopy department before the procedure. Results: The study comprised a total of 145 patients, 73 of whom were men. The pre-procedure questionnaire showed that the anxiety scores of patients who answered yes to the question "Are you afraid of undergoing an endoscopy?" were statistically significantly higher than those of patients who responded no (T-Anxiety: p=0.003, S-Anxiety: p<0.001). When comparing the genders according to the responses to this question, it was found that the rate of yes responses was significantly higher in females [57 (78.1%)] than in males [30 (41.1%)] (p[removed
Susceptibility to cyanidation of pyrrhotite-associated gold in pyrite calcines from (non)oxidizing roasting environments
No full textThe susceptibility to leaching of pyrrhotite-associated gold in roasted pyrite calcines was studied, with emphasis on the effects of the roasting environment and galvanic contacts under cyanidation conditions. The first part scrutinized the thermal treatment of pyrite under different oxidizing and non-oxidizing atmospheres, and demonstrated that air roasting promoted the coexistence of multiple pyrrhotites, while He, CO2, and steam environments resulted in single hexagonal pyrrhotites with increasing iron deficiency and decreasing porosity. The second part employed a bilayer leach cell to control the electrochemical contacts between gold powder and raw/roasted pyrite during cyanidation, and found that the topology of pyrrhotite and iron oxides was influenced by the type of roasting treatment, which could impact the kinetics of gold dissolution, particularly in cases involving refractory gold or ore preg-robbing recalcitrance. Therefore, when it comes to extracting encapsulated gold associated with refractory pyrite that requires heat treatment, air roasting was the most effective for leaching gold from calcine, outperforming both inert and mild oxidative environments. In addition, the presence of CO2 (and/or moisture) in the roasting atmosphere to mimic the combustion of carbonaceous material could moderately enhance gold recovery regardless of whether or not there was galvanic contact with the roasted pyrite
Atomic Fe on hierarchically ordered porous carbon towards High-performance Lithium-sulfur batteries
No full textLithium-sulfur (Li-S) battery is the promising next-generation energy storage device owing to its ultra-high theoretical energy density and low cost. Unfortunately, its practical performance is significantly hindered by the poor conductivity of sulfur, huge volume change, and soluble lithium polysulfides (LiPSs). To address above issues, single iron (Fe) atoms anchored on hierarchically porous carbon substrate configured by ordered macropores and widespread mesopores/micropores (Fe[sbnd]N[sbnd]C/OC) are synthesized and acted as carbon hosts for sulfur cathodes. Single Fe atoms in Fe-N4 moieties serve as active sites to accelerate conversion kinetics of LiPSs due to strong catalytic ability, thereby the shuttle effect being obviously restrained. Meanwhile, the trimodal-porous structure provides continuous carbon framework for enhanced electrical conductivity, ordered macroporous channels bridged by mesopores for rapid Li+ diffusion, and adequate spaces to reserve sulfur volume oscillation. Consequently, sulfur-loaded Fe[sbnd]N[sbnd]C/OC (Fe[sbnd]N[sbnd]C/OC/S) cathodes exhibit an impressive specific capacity of 1442 mAh g−1 at 0.1C and maintain the capacity retention of 89.2 % after 300 cycles at 1C. It offers fresh insights for designing efficient sulfur hosts to enhance the performance of Li-S batteries
Thermal plasma synthesis of (La,Sr)CoO3-(La,Sr)2CoO4 composite cathodes for intermediate temperature solid oxide fuel cells (IT-SOFC)
No full text(La,Sr)CoO3 and (La,Sr)2CoO4 dual phase powders were synthesized via thermal plasma to be used as cathodes for intermediate temperature solid oxide fuel cells (IT-SOFC). This covered pure (La,Sr)CoO3 as well as the composites where the fraction of (La,Sr)2CoO4 was gradually increased reaching the mid-composition. Powders, all synthesized in the same condition, were extremely small in size, especially at mid-composition where they were close to 30 nm in size. Area specific resistance (ASR) determined from the symmetric cell imply improved cathodic performance at the mid-composition. Taking ASR = 0.15 Ω∗cm2 as benchmark, it was found that the (La,Sr)CoO3: (La,Sr)2CoO4 = 0.53:0.47 cathode may be used at temperatures close 750 °C. Measurements taken from several runs however imply that the cathode performance was not stable and ASR values increases with cycling. This was attributed to the powder form of the cathode which would be expected to coarsen rapidly due to accelerated surface diffusion
The Role of Community Based Tourism in Avoiding Overtourism
No full textOvertourism is one of the terms that has appeared in the literature recently, meaning the excessive number of tourists and the impacts of their flows on local communities and ecology. The increase in anti-tourism events around the world is a significant indicator of the effects of overtourism on communities. The underlying reason for the problem is mainly based on the decisions which were taken in a hurry, without proper evaluation, consideration of necessary matters, and often without active participation and inclusion of communities. Community development intends to flourish social, economic, environmental and cultural welfare and prosperity of communities, particularly made up of disadvantaged and marginalized people. Community based tourism development is one of the key factors to avoid that senseless anti-tourism sentiment and proceed to bring societies and cultures closer together through developing understanding and contact. Growing guest arrivals inflict an intense pressure on the environment and local community and their culture in a destination, thereby deteriorating both the quality of tourists’ experiences and the life quality of local people. Rapid growth in tourism and undesirable condensation disrupt the sustainability of a destination causing local community and other stakeholders no more show any interest in further tourism development and making them feel they suffer since their access to opportunities, comfort, and health etc. is inhibited. It is significant that the technological revolution and intense usage of social media by tourists have been triggers to overtourism. However, COVID-19 Pandemic period may be an opportunity to invest both in technology and the further to help mitigate overtourism after COVID-19 when the crowd come back. In this context, this chapter explains the importance of community development in tourism and indicates considering community frustration to avoid adverse effects of tourism, in particular overtourism, and mentions how technology could be utilized in this period
Recent advances in availability and synthesis of the economic costs of biological invasions
No full textBiological invasions are a global challenge that has received insufficient attention. Recently available cost syntheses have provided policy- and decision makers with reliable and up-to-date information on the economic impacts of biological invasions, aiming to motivate effective management. The resultant InvaCost database is now publicly and freely accessible and enables rapid extraction of monetary cost information. This has facilitated knowledge sharing, developed a more integrated and multidisciplinary network of researchers, and forged multidisciplinary collaborations among diverse organizations and stakeholders. Over 50 scientific publications so far have used the database and have provided detailed assessments of invasion costs across geographic, taxonomic, and spatiotemporal scales. These studies have provided important information that can guide future policy and legislative decisions on the management of biological invasions while simultaneously attracting public and media attention. We provide an overview of the improved availability, reliability, standardization, and defragmentation of monetary costs; discuss how this has enhanced invasion science as a discipline; and outline directions for future development
Investigation of the effects of pesticides on ‘Jonagold’ apple (Malus x domestica) polyphenol oxidase enzyme activity
No full textIn this study, the effects of a number of commonly used pesticides on the activity of the polyphenol oxidase (PPO) enzyme from pesticide-free and pesticide-applied ‘Jonagold’ apples were comparatively evaluated. Substrates 4-methylcatechol, pyrocatechol, pyrogallol and L-tyrosine were used to determine the substrate specificity of the PPO enzyme obtained from apple. According to the results, on the contrary, PPO enzyme from ‘Jonagold’ apple did not show any activity against L-tyrosine substrate which is a monophenolic substrate, the enzyme had high affinity against 4-methylcatechol, pyrocatechol and pyrogallol which are di and tri phenolic substrates. Km values of PPO enzyme obtained from pesticide-free apples against 4-methylcatechol, pyrocatechol, and pyrogallol substrates were determined as followed 0.27 mM, 2.27 mM, and 0.37 mM, respectively. Vmax values were found as 0.133 mM/min, 0.081 mM/min, and 0.051 mM/min. Optimum pH values were found to be 4.5 for 4-methylcatechol, 7.0 for pyrocatechol, and 7.5 for pyrogallol. Optimum temperature values were determined as 40 °C for 4-methylcatechol, 10 °C for pyrocatechol, and 50 °C for pyrogallol. Km values for PPO enzyme activity obtained from pesticide-treated apples against 4-methylcatechol, pyrocatechol, and pyrogallol substrates were 0.98 mM, 3.94 mM, and 0.37 mM, Vmax values were 0.08 mM/min, 0.02 mM/min, and 0.034 mM/min. Optimum pH values were found to be 7.0 for 4-methylcatechol and pyrocatechol and 7.5 for pyrogallol. Optimum temperature values were determined as 50 °C for 4-methylcatechol, 30 °C for pyrocatechol, and 40 °C for pyrogallol. Overall, the results showed that the PPO enzyme from pesticide-free apples had higher activity than pesticide-treated apples. The effects of metals and storage stability on PPO enzyme activity were also investigated. The results reveal that pesticide use affects PPO enzyme activity. The obtained data bring to light new pesticide functional features of great interest in the medicinal, agro-chemical and environmental circles