Alternative Sources Of Supply Research Articles

Understanding residents’ choice of urban farming systems in the Kumasi metropolis of Ghana: Land use policy implications

The heightened food insecurity in urban settings has rekindled the debate over the promotion of urban agriculture (UA) as a sustainable alternative food supply source across the globe. This study, therefore, examines the determinants of urban residents’ decisions to engage in UA and their choice of agriculture practices. Cross-sectional data was solicited from 430 urban dwellers through a multi-stage sampling technique. The data was analysed using descriptive as well as binary and multinomial logit regression models. The descriptive analysis shows that the cultivation of crops (34.7 %) predominates urban agricultural practices before crop-livestock integration (32.6 %) and livestock farming (32.6 %). The study identifies gender, age, religious affiliation, years of formal education, location of residence, household size, food insecurity status, availability of vacant land, extension access, and household income as significant determinants of urban households’ decision to participate in UA. The multinomial logit regression analysis revealed that urban farmers’ decision to practice only crop production is invariant between livestock-only production and integrated crop-livestock systems. When compared to the base category of the integrated crop-livestock system, the findings indicate that farmers’ educational background, food insecurity, engagement in salaried jobs, location, extension, and credit access are the main drivers of the decision to practice either crop-only or sole livestock production systems. The findings of this study have useful implications for the formulation of UA programs based on the different farming systems practiced in the study location.

Characterization and risk assessment of polycyclic aromatic hydrocarbons from the emission of different power generator

Epileptic power supply in Sub-Saharan countries of Africa has warranted the use of power generators as an alternative source of power supply. Exhaust emission from these generators is associated with Polycyclic Aromatic Hydrocarbon (PAHs). Hence, this study focused on the determination of levels of PAHs in the emission of different brands of power generators used in Nigeria. Exhaust emissions of different power generators were sampled using a filter-sorbent sampling system with polyurethane foam (PUF) as an adsorbent material. Analysis of PAHs was carried out using a Gas Chromatograph coupled to a mass selective detector (GC- MS) operated on Electron Ionization (EI) mode. The results showed the ∑ PAHs range 14.91–26.0 μgm−3. Bap was the most abundant of all the compounds with a concentration of 2.6 μgm−3 with a range of 2.08–3.07 μgm−3. The Incremental Life Cancer Risk (ILCR) values of all the generator's emission sampled are higher than 10− 4 for both children and adult which indicate a high potential cancer risk from inhalation of emission from these generators while Hazard Quotient (HQ) values from all the power generating set in this study are all above 1 which indicated high associated non-carcinogenic. The study revealed the levels of PAHs associated with the emission of power generators in Nigeria.

Bioactive Compounds from Organic Waste.

The reuse and reincorporation of waste are the principles of circular economies. Compost, biofuels, animal feed, dyes, and bioactive compounds can be obtained from the revaluation of organic waste. Research on this subject is scarce and limited to specific sectors, such as agriculture and agroindustry, leaving aside others that generate large quantities of organic waste, such as floriculture. The remains of these sectors have a low decomposition rate compared to other organic wastes. They are a source of bioactive compounds (e.g., essential oils, pigments, phenols) that can be reincorporated into the production chain of various industries. This review describes the composition of waste from agroindustry, agriculture, and floriculture, analyzing their potential revalorization as a source of bioactive compounds and an alternative supply source.

The determination of the features of the process of mixture formation of hydrogen burner

The use of hydrogen fuel as an alternative source of individual heat supply is a rather promising direction in the development of thermal energy. However, due to the physical properties of hydrogen and the peculiarities of its combustion, several problems arise for the practical use of hydrogen heat generators. Such problems include ensuring flare stability and large emissions of thermal nitrogen oxides (NOX). For stable operation of the hydrogen burner, safe operation, and reduction of nitrogen oxide emissions when burning hydrogen, first, it is necessary to ensure high-quality pre-mixing with air. This work presents the first stage of research into the operation of a hydrogen burner for heat production in the Flow Simulation module of the SolidWorks software environment. For volume flow rates of air and hydrogen corresponding to capacities of 1, 1.5 and 2 kW and air excess coefficient α=1.6. The given design makes it possible to ensure uniform mixture formation (the volume fraction of hydrogen is approximately 18.5 % at the outlet cross-section of the burner and the speed at the outlet of the burner is 5.4, 8.1, and 10.8 m/s, respectively. The burner is a nozzle with a short premixing chamber First, hydrogen is supplied for mixing into the air flow through symmetrically located holes. After that, a vortex is created, which ensures high-quality mixing of gases with a short length of the burner, as well as a uniform distribution of velocity at the exit. The obtained results allow to proceed to the next stage – the study of hydrogen combustion processes in the combustion chamber of the contact heat generator, which would ensure the formation of a stable flame and low NOX emissions. In addition, this design can be used in the development of hydrogen burners for heating boilers to meet the needs of private homes and small businesses

Comparative study on the extraction strength of solvents on tar sand from Okitipupa, Ondo State

Tar sand, an aggregate of sand, clay, water and bitumen was sampled from Okitipupa area of Ondo State, Nigeria, extracted and optimized using n-hexane and toluene in a soxhlet extractor todetermine solvent effectiveness in extracting the bitumen content and their environmental effect. The experiment was carried out by heating the solvent at and above their boiling temperatures solely to get an optimum yield at a temperature and time of extraction of oil from the tar sand. The analysis gave an optimal yield of 9.07 % at 75oC in 4 h when n-hexane was used and an optimal yield of 21.27 % at 120oC in 4 h when toluene was used. A drastic change in colour was also notice in the sand residue to almost sandy soil nature when toluene was used as solvent compare to when n-hexane was used which shows a slight change from its blackish nature. The change in colour of the black tar sand is an indication of high extraction efficiency. Hence, owing to high demand for conventional oil supply in the country and the urgent need for an alternative source of oil, the bitumen extract can serve as an alternative source of unconventionaloil supply in Nigeria and feedstock in refineries.

Can On-Farm Wood Meet the Global Wood Supply and Save Tropical Forests? A Systematic Review

Global wood supply is faced with an annual escalating scarcity threat by population growth and increased wood demand. Natural forests, a chief source of wood, are under pressure from massive deforestation and degradation, whereas plantation forests are faced with challenges of land tenure and competition from other land uses. This systematic review aimed to point out the contribution of on-farm trees to global wood supply and tropical forest conservation. The study adopted the Sample-Phenomenon of Interest-Design-Evaluation-Research type framework to identify relevant literature. Both grey and peer-reviewed publications were considered. Of the 3800 publications identified, 42 substantially met the inclusion criteria and were selected for data extraction. A huge imbalance was evident in the wood supply and demand that forest production could not satisfy alone. On-farm trees were observed to be a significant alternative source of wood supply in South Africa, India, and Kenya, supplying 27, 36, and 70 per cent of total apparent consumption, respectively. Where importation reliance was low and a low forest production rate, on-farm trees contributed more than 50% of the total apparent consumption. China had a high reliance on importation. On-farm trees contributed at least a supply of 8% of total apparent consumption. On-farm trees were the chief source of wood fuel. On-farm trees contribute substantially to the supply chain of industrial roundwood, woodfuel, and sawn wood, reducing the need to infiltrate the forests. Where the full potential of on-farm trees is inadequately exploited, on-farm trees can sustainably contribute to the wood supply chain and save tropical forests

СИСТЕМА УПРАВЛІННЯ СТІЙКІСТЮ ТА АДАПТИВНІСТЮ ЛАНЦЮГІВ ПОСТАЧАННЯ РОЗДРІБНИХ ПРОДОВОЛЬЧИХ МЕРЕЖ

The article examines the primary meanings of 'supply chain adaptability' and 'supply chain resilience'. The aim is to assess the resilience and adaptability of retail food supply chains during the declaration of martial law in Ukraine. Supply chain adaptation is focused on responding to specific changes or challenges, while supply chain resilience encompasses a broader range of measures and strategies to ensure the continuity and efficiency of the supply chain during stressful or crisis situations, such as times of civil emergency. Supply chain adaptation is the process of modifying supply chains to address specific challenges or conditions, such as changes in market conditions, technological progress, or changes in consumer demand. In situations where martial law is in effect, supply chain adaptation may include changing suppliers, revising logistics processes, seeking alternative sources of supply, and taking other measures to ensure continuity of the supply of goods and services. Supply chain resilience refers to the capacity of a supply chain to endure challenging situations and sustain operations, even in the face of adverse impacts, such as military conflict. It is important to acknowledge that supply chains can face diverse challenges, and it is crucial to maintain efficiency and productivity, irrespective of external circumstances. The main problems of implementing resilience and adaptability of the food supply chain in Ukraine during the declaration of martial law are identified to ensure the reliability and food security of the country in the context of military conflict. It suggests that studying the resilience of the food supply chain is crucial for ensuring its smooth and efficient functioning, particularly during times of crisis and stress, to maintain the country's food security. Under such conditions, there may be a risk of supply disruptions, transportation issues, reduced production, and higher food prices. It is important to consider developing and implementing strategies and measures to ensure stability and food security under martial law. This could include crisis response planning, the exploration of alternative supply routes by retailers, the organization of food reserves, and the coordination of efforts between various sectors and governing bodies. The methodology proposed by the author assesses the factors that affect the resilience of food supply chains during the declaration of martial law in Ukraine.

Water from alternative supply sources in Paraná State: potability and map of vulnerable groups

The present study describes a survey based on data provided by the National Program of Water Quality Surveillance for Human Consumption, also known as Vigiagua, carried out between January 2020 and December 2022. Great challenges were observed in nine municipalities composing the 4th Health Regional of Paraná State. In total, 35.75% of all 2,078 analysis reports presented registration mistakes. Imbituva, Mallet and Rio Azul were the municipalities mostly affected by this issue. Quality of water significantly varied among municipalities; it showed high indices of both inconclusive or not-recorded reports in Inácio Martins, Teixeira Soares and Guamiranga. Fernandes Pinheiro was the municipality accounting for the largest number of non-compliant reports about water turbidity and contamination by Escherichia coli. The availability of Information about quality of water in alternative supply sources was limited, despite the large number of analyzed samples - some municipalities did not meet the standards set for E. coli presence. Based on cluster analysis, rural areas, and traditional peoples and communities, such as faxinalenses and indigenous peoples, are the most vulnerable ones.

Ukraine’s energy supply in the defense sector: The first lessons of war

The terrible consequences of the Russian-Ukrainian war, which continues on the territory of the Ukrainian land, and the consequences of natural disasters indicate the need to create alternative (reserve or emergency) sources of energy supply for enterprises, institutions, and individual households, and objects of small forms of management, especially outside the points of permanent deployment. Ensuring an uninterrupted and stable electricity supply to all these forms is an extremely important problem for Ukraine as the country faced a large number of challenges regarding energy independence due to numerous missile strikes. The purpose of the study was to analyze the energy system and the level of damage to Ukraine after the Russian missile attacks, the impact on the state of energy supply of individual facilities and consumers of military camps, examine the possibilities of using emergency and backup energy sources and alternative energy, in particular, solar and wind. The study analyses the destruction of the energy system of Ukraine as a result of missile attacks and the possibilities of using emergency and backup energy sources and alternative energy, in particular, solar and wind, and the investigation of the potential and opportunities to attract investment in the field of alternative energy. Special attention is paid to small business facilities, including military camps. In the course of the study, it was determined that Ukraine has a geographical location that provides space for the installation of various alternative energy systems and the possibility of combining them to diversify and improve the stability and reliability of the Ukrainian energy system. The practical importance of the study lies in the ability to make more informed decisions regarding the implementation of programs aimed at switching to alternative and decentralized energy sources. This will make the country’s energy infrastructure more stable and allow better meeting the energy needs of small forms of management, individual farms, military units, formations, and infrastructure facilities.

Normobaric hypoxia and exercise training effects on cardiac biomarkers, left ventricular function and aerobic performance in patients after myocardial infarction

Abstract Background Chronic total occlusion (CTO) has a negative impact on the left ventricle function and long-term prognosis of the patients after myocardial infarction. Scientific evidence suggests that some patients with CTO develop collateral arteries which provide an alternative source of blood supply to myocardium and can help to preserve myocardial function. One of the factors influencing the formation of collateral circulation is hypoxia, which induces angiogenesis and arteriogenesis. Physical activity is the most effective stimulus for adaptive changes in cardiovascular hemodynamics. However, the use of hypoxia and endurance exercise training on hemodynamic parameters of the heart and angiogenic factors have not been thoroughly studied yet. The aim of the present study was to examine the effect of endurance training under normobaric hypoxia on cardiac-specific troponin T (cTnT), creatinine kinase-myocardial band (CK-MB), heart-type fatty acid binding protein (H-FABP), vascular endothelial growth factor (VEGF), cytokines and cardiovascular function in patients after myocardial infarction. Methods Patients aged 60.4 ± 4.4 years who had undergone angioplasty with stent implantation participated in the study. Due to high risk of the occurrence of side effects cause by normobaric hypoxia only patients with stable coronary diseases (participants of the second stage of cardiac rehabilitation program) were included. The training program included 3 weeks of endurance training in normobaric hypoxia (HypTr) corresponding to an altitude of 2000 m above the sea level (FiO2 = 15.0%; (HYP-123 Hypoxic Generator, LOWOXYGEN Technology GmbH, Germany). The training regimen comprised 5 sessions/week with 5 min of warm-up, 30 min of interval training (intensity 80% of HRpeak) and 5 min of cooling down. Spiroergometry (CORTEX METAMAX 3B analyzer ) was performed using the cardiopulmonary test Electrocardiography and cardiac biomarkers were evaluated before and after the three weeks of the training programme. Results An increase in average distance covered (622.7 ± 119.0 vs. 687.0 ± 126.7 m, p<0.01) and the test duration (10.4 ± 1.0 vs. 11.0 ± 1.7 m, p<0.05) were observed in response to exercise training in hypoxia. CK-MB (p<0.05) and cTnT (p<0.05) levels were lower post-training compared to the pre-training (p < 0.05). Training in hypoxia had a significant effect on hemoglobin (F=14.7 p<0.001), TNF β (F = 8.2 p<0.01) and VEGF (F = 7.4 p<0.1) levels. Left ventricular (LV) function was altered post-training and the alteration was characterized by favorable changes in end-diastolic and end-systolic dimensions and LV ejection fraction (p<0.05). Conclusions Exercise training in normobaric hypoxia had a significant positive effect on the left ventricular function and concentration of the specific cardiac biomarkers, therefore it may play a crucial role in the cardiovascular adaptive mechanisms in patients after myocardial infarction.

Shrinkage performance and modelling of concretes incorporating crushed limestone sand with a high content of fillers for pavement slabs

Because of the gradual depletion of gravel and river sand resources and restrictions on quarrying activities to maintain the ecological balance, limestone crushed sand with a high content of limestone fillers is being explored to be used, as an alternative source of supply, in Portland cement concrete (PCC) for rigid pavement. This paper aims to first present mechanical test results carried out on three types of PCC formulated with crushed limestone sand as fine aggregates, devoid of superplasticizers. Since shrinkage cracking is an important problem for rigid pavement, the shrinkage behaviour of these concretes is then experimentally investigated. Furthermore, three existing models (ACI-209, Eurocode2, and triple-sphere models) and a novel-developed model are used to estimate the mixtures’ shrinkage. Results showed that the designed mixtures exhibited normal shrinkage values. The shrinkage modelling revealed that the proposed model well fitted the experimental data. Besides, Eurocode2 and ACI-209 models may be adapted for the case of limestone concretes containing a high content of limestone fillers and then used to accurately estimate their shrinkage strains. However, the triple-sphere model was unsuitable for these concretes and overestimated their ultimate shrinkage since it does not take into account their high filler content. Nevertheless, by adjusting the paste shrinkage expression, the ultimate shrinkage strain values of the tested mixtures were improved.

Logistics chain responsiveness to war impacts: A case study in North Adriatic Region

The Russian-Ukraine conflict outbreak abruptly interrupted the sea-road intermodal service which provided some metal companies in the Italian region of Friuli Venezia Giulia with semi-finished steel products coming from the Ukrainian port of Mariupol. Those companies were then forced to find an alternative supply source to feed their production system, which entailed the arrival of oceanic vessels with a greater cargo load, but at a lower frequency. Such changes implied significant consequences both on the maritime and the land side and requested the employment of trucks, train and barges to transfer the increased volume of goods. Moreover, those variations generated additional costs for all the involved operators, threating the survivability of the whole supply chain and, thus, of an important share of the regional economy. In this paper, a methodology combining process modelling and quantitative analysis has been applied, first, to gain an in-depth understanding of the case study and then, to suggest modifications to existing policies. Such investigation techniques enabled, on one hand, to identify process bottlenecks and, on the other hand, to examine infrastructural and financial consequences for each considered transport mode. Results revealed the need of adjusting the current strategic vision especially with reference to the development of the infrastructural networks, the introduction of incentive schemes and the availability of skilled people operating in logistics. The proposed lines of action are meant to foster the resilience of the analysed supply chain at economic, environmental and social level.

Sustainability assessment of the solar energy supply chain in Colombia

Solar-generated energy supply has been applied as a solution to address the increasing global population, global warming challenges, and the search for alternative sources of renewable and clean energy supply. Regions such as Latin America and the Caribbean have a significant rural population that lacks access to electricity, impeding their development, and increasing unemployment rates. This paper presents a system dynamics model (SD) for assessing the implementation of a solar energy supply chain (SESC), combining the analysis with the national industry's development for the manufacture of solar modules used in the implementation of solar farms and individual solution projects, especially in the non-interconnected zones of Colombia. This case study examines three scenarios in Colombia: national government-implemented solar farm projects; development of national supply chain implementation; and development of the solar energy market. These scenarios are evaluated using performance indicators for supply chain variables, including coverage, diversification, emissions, and job creation. The results indicate that implementing a supply chain and developing solar module production in Colombia can positively impact the proposed indicators, resulting in improvements of 5.9% in coverage, 6.3% in diversification, 6.7% in emission reductions, and 13% in job creation.

An overview on non-wood fiber characteristics for paper production: Sustainable management approach

The amount of paper and paperboard a country uses are a reliable barometer of its development. Having access to them is essential to our daily life. The Indian paper industry faces a number of challenges, one of which is a scarcity of high-quality raw materials. Agricultural waste products have become essential alternative sources of supply as a result of an increase in the need for fibrous raw materials, a global lack of trees, and a growing awareness of sustainability. When compared to the manufacturing of pulp and paper from wood sources, the use of non-wood sources (including bagasse, maize stalks, cotton stalks and rice straws) offers a number of advantages. These benefits include superior quality of the bleached pulp and excellent sources for specialty papers. Paper manufacture is more ecologically friendly and sustainable when non-wood fibers are processed since non-wood pulping technologies use less energy than wood-based pulping processes. Furthermore, the financial advantages include cost savings, market differentiation, enhanced sustainability, and access to government subsidies. By investing in non-wood fibers to satisfy rising customer demand for environmentally friendly goods, paper manufacturers may position themselves for long-term prosperity and environmental responsibility. The non-wood fibers are cellular and have a complex cell wall structure. A thorough understanding of their properties is essential for effective use. Therefore, the objective of the present review is to explore the wide variation between critical characteristics (morphological, chemical, and mechanical) and the most appropriate pulping and bleaching processes for commonly used agricultural residues (Rice straw, Bagasse, Wheat straw and Bamboo) in the Indian pulp and paper industry for the production of paper, board, and packaging.

An Economic Analysis of Anti-Profiteering Law in Malaysia

In Malaysia, the Price Control and Anti-Profiteering Act 2011 contains both price control and anti-profiteering provisions. A profiteering offence is committed when a seller makes an ‘unreasonably high profit’ which is further defined as exceeding a mark-up percentage or margin percentage from a baseline profit on the first day of the financial year or calendar year of business. Neoclassical microeconomic theory teaches that regulatory control over prices is inefficient and harms consumers more than does any good. Violations of the anti-profiteering provision are challenging to detect as prices may increase due to increased costs. Contrary to the rationale for anti-gouging laws, allowing businesses to increase prices due to a shortage of supply may save consumers from unnecessary searches for the illusive low-price controlled products and further incentivise sellers to seek alternative sources of supply. In a competitive market, market discipline by consumers is sufficient to deter businesses from raising prices beyond competitive market prices. Competition law and mandatory price marking law should be used to address uncompetitive market conditions. Perhaps, for these reasons, there are no more new reported cases of enforcement of the anti-profiteering law in the news since 2016 despite having a reported appeal decision in 2020.

Analysis of the application of modern means of detection and measurement of carbon monoxide when using alternative sources of electricity supply during the war in Ukraine

The article examines the impact of carbon monoxide on the human body, as well as the necessity of its detection and measurement. Carbon monoxide poisoning is very dangerous for human health and is accompanied by negative consequences and requires the implementation of new means of its timely detection and measurement. The article identifies the main sources of carbon monoxide, as well as assesses its impact on public health. The choice of modern means of detecting and measuring carbon monoxide is an important and necessary component of protecting people in modern realities. The work examines and analyzes the technical capabilities of modern cpaabilities of determining the level of carbon monoxide, defines the main models of carbon monoxide detectors, and also classifies and systematizes the peculiarities of their operation. The most convenient and practical portable carbon monoxide sensor. It does not require stationary installation. This is especially important in closed rooms, where carbon monoxide poisoning can occur instantly. The article analyzes literary sources in the field of the main types of alternative energy sources used in Ukraine during emergency and planned blackouts, as well as the dangers associated with them. The influence of dangerous and harmful factors affecting the human body during the use of these devices is considered: power banks, generators, batteries and inverters. The analysis of scientific research on ensuring safety when using alternative energy sources in domestic premises, private and multi-story buildings, factories, underground passages and storages was performed. The features of each type of modern signaling devices are analyzed. Recommendations are provided for the selection of modern means of detecting and measuring carbon monoxide.

Adaptive Planning: A Resilience Model for Communities

Key TakeawaysFor many communities across the United States, shifting trends in climate and other environmental conditions are threatening water supplies.The pressure is on water providers to adapt—to explore alternative supply sources and develop resilience strategies for the long term.Aspen, Colo., enhanced the reliability of its water supply and closed the gap between supply and demand with integrated water planning.Aspen created and evaluated several options for its 50‐year adaptive plan, considering climate impacts on supply and demand as well as other potential threats.

Consideration of liquefied natural gas as an alternative source of gas supply to Ukraine

The object of research is the energy sector of Ukraine, specifically the gas supply system of the national economy. One of the most problematic places is the dependence of the Ukrainian economy on the import of natural gas (NG). Ukraine is rich in various natural resources, in particular, in natural and associated gas. However, own wells for NG extraction are not enough for gas supply to industrial enterprises and the population. Therefore, part of the necessary gas is imported. In the course of the study, methods of alternative supplies were analyzed, namely, liquefied natural gas (LNG), options for its supply with subsequent regasification were analyzed. The global market for liquefied natural gas (LNG) was studied and it was shown that the production and consumption of LNG is constantly increasing. Since Ukraine is part of Europe, and the main suppliers of LNG for European countries are the USA and Norway, one of the options for gas supply for Ukraine considered the supply of LNG to the territory of Poland by sea transport, its regasification and subsequent transportation to consumers through existing pipelines. The second option is the supply of LNG to the Ukrainian coast of the Black Sea. To do this, it is necessary to study prospective transportation routes, build logistics and terminals for receiving and regasifying LNG. Since the depth of the channels from the Mediterranean to the Black Sea is small, the option of supplying natural gas from Central Asia by pipeline to the Black Sea coast of Georgia, its liquefaction, transportation by sea and regasification is proposed. This option requires significant capital expenditures for the construction of a natural gas liquefaction plant on the territory of Georgia and a regasification complex on the Ukrainian coast or a floating terminal. In the course of the work, LNG quality criteria used in the world were studied, and it was noted that for the purchase and use of LNG in Ukraine, it is necessary to develop own standards for controlling its composition. Because the technology of providing the consumer with natural gas using LNG is more flexible than pipeline transport. Its implementation will make it possible to provide Ukraine with natural gas in the required quantities and, if necessary, to promptly change the volume of deliveries.

INVESTIGATING THE IMPACT OF ELECTRICITY SUPPLY INTERRUPTIONS ON THE EXPANSION OF SMALL AND MEDIUM SIZE ENTERPRISES (SMEs): A SYSTEMATIC LITERATURE REVIEW

This paper aims to investigate the factors that impact electricity supply interruptions on small and medium-sized enterprises (SMEs) in Cameroon and the theories used by researchers in preventing electricity supply interruptions. The method used is a systematic literature review of empirical studies on factors responsible for various forms of electricity supply interruptions and their impact on businesses worldwide. The author of this study examined 70 publications from 2012 to 2022 within the scope of the subject and analyzed the factors responsible for interruptions and prevention techniques used to curb the interruption of electricity supply. The results revealed that human factors, technological factors, and atmospheric & environmental factors have impacts on the interruption of electricity supply. Further, the study found that most of the publications on the subject were case studies (74%), while the remaining studies comprised Quantitative studies (19%), Qualitative studies (7%), and 0% for mixed studies research. It was also revealed that technological, human, atmospheric, and environmental factors are more responsible for electricity supply interruptions in developing countries than in developed countries. The results imply that electricity network designers need to mitigate electricity interruptions by employing modern techniques. The study recommends that alternative electricity supply sources could be used to help reduce interruptions, especially using other renewable energy sources like solar electrification systems and generators as backup or supplementary systems to enhance the electricity supply.

Evaluation of myocardial viability by a secondary delayed 99mTc-MIBI nuclear scanning in ST-elevation myocardial infarction patients with delay in referral and nonviable myocardium in the first scintigraphy: a preliminary cohort study.

In the management of ST-segment elevation myocardial infarction (STEMI), if the treatment has not been initiated within the first 24 h and the patient no longer exhibits any symptoms, the decision to begin revascularization therapy is based on myocardial viability. If the tissue is nonviable, current guidelines advise against further revascularization therapy; however, collateral vessels represent an alternative source of blood supply and may help the damaged tissue to resume function; though at first, this tissue may not be considered viable. Thus, in patients whose first myocardial perfusion scintigraphy (MPS) revealed nonviable myocardium, a secondary MPS to assess viability may be beneficial and alter the course of treatment strategies. This prospective cohort study was conducted on 30 STEMI patients referred to Mazandaran Heart Center. If no myocardial viability was found using 99mTc-MIBI MPS, the patient was referred for a secondary MPS after 3 months. In total, out of 30 patients, 3 became viable. There was no significant relationship between the viability of different Rentrop classes. Comparison of viability between patients with different numbers of occluded vessels showed no significant relationship. Three patients (17%) among 17 patients with Rentrop class nonzero became viable in the second MPS. Also, among four patients (13.3%) with Rentrop class three, one patient (25%) became viable and among seven patients (23.3%) with Rentrop class one, two patients (28.6%) became viable. Considering the results of this study, although nonsignificant, this subject requires further investigation to reach a definite conclusion.