Energy Production Levels Research Articles

Оценка эффективности завихрения воздуха при распылении водоугольных суспензий пневматической форсункой

Due to modern requirements for environmental protection, introduction of environmentally friendly power engineering technologies involves search and development of new energy sources. One of the ways to meet these requirements and maintain the same level of energy production by thermal power plants is to use multicomponent fuels. The most promising and affordable heavy fuel oil from the point of view of energy, ecology and economy are coal-water slurries (CWS). In this regard, the study of the properties and characteristics of such fuels is relevant. The coal-water slurries have been prepared in a rotary hydrodynamic cavitation generator. A pneumatic atomizer with external mixing is used to spray the coal-water slurries. Interferometric Particle Imaging method is used to determine the average size of fuel droplets after atomization. The authors have conducted experimental studies of the characteristics of atomization of coal-water slurries based on lignite and pyrogenetic liquid with a pneumatic atomizer with a tangential supply of a spraying agent. A three-stage method to prepare lignite-based slurries with pyrogenetic liquid has been tested. It has been established that when using this technique, the fluidity of coal-water fuel is maintained even with the introduction of 20 % by weight of pyrogenetic liquid into the composition of coal-water slurries when replacing both water and coal in equal proportions. The kinematic viscosity of coal-water suspensions increases when pyrogenetic liquid is added, despite a decrease in the concentration of the solid component. The change of suspension density is insignificant. The results of the study of atomization process have shown that the tangential air supply to the atomizer leads to an increase of the jet spraying angle by 6° compared with direct supply. At the same time, the average droplet size in the jet of a two-component CWS with direct air supply is 8 % smaller. The results of the study have made it possible to obtain completely new knowledge that can significantly advance domestic and world science and technology in the field of power engineering, namely the technology of coal-water fuels atomization. Experimental studies have determined the main patterns of influence of the CWS properties and the method of spraying agent supply on the formation of a gas-drop jet. Such patterns will provide conditions for the effective atomization of quite viscous CWS in the combustion chambers of energy boilers. The results obtained will enable designers and constructors to develop highly efficient designs of steam and hot water boilers and gasifiers fueled by CWS.

Bidirectional Effect of Long-Term Δ9-Tetrahydrocannabinol Treatment on mTOR Activity and Metabolome.

Brain aging is associated with cognitive decline, reduced synaptic plasticity, and altered metabolism. The activity of mechanistic target of rapamycin (mTOR) has a major impact on aging by regulating cellular metabolism. Although reduced mTOR signaling has a general antiaging effect, it can negatively affect the aging brain by reducing synaptogenesis and thus cognitive functions. Increased mTOR activity facilitates aging and is responsible for the amnestic effect of the cannabinoid receptor 1 agonist Δ9-tetrahydrocannabinol (THC) in higher doses. Long-term low-dose Δ9-THC had an antiaging effect on the brain by restoring cognitive abilities and synapse densities in old mice. Whether changes in mTOR signaling and metabolome are associated with its positive effects on the aging brain is an open question. Here, we show that Δ9-THC treatment has a tissue-dependent and dual effect on mTOR signaling and the metabolome. In the brain, Δ9-THC treatment induced a transient increase in mTOR activity and in the levels of amino acids and metabolites involved in energy production, followed by an increased synthesis of synaptic proteins. Unexpectedly, we found a similar reduction in the mTOR activity in adipose tissue and in the level of amino acids and carbohydrate metabolites in blood plasma as in animals on a low-calorie diet. Thus, long-term Δ9-THC treatment first increases the level of energy and synaptic protein production in the brain, followed by a reduction in mTOR activity and metabolic processes in the periphery. Our study suggests that a dual effect on mTOR activity and the metabolome could be the basis for an effective antiaging and pro-cognitive medication.

Solar energy feasibility for power generation in lower shire districts: A case study of Chikwawa District

Background: Electricity availability is an essential part of both economic and non-economic activities in any country. Malawi being one of the developing nations experiences a lot of challenges both in its economic and non-economic activities due to unlimited levels of electric supply in its country. This inadequacy of limited supply has remained a challenge for a longer period of time to the effect that the country Malawi for a longer period of time has an overwhelming record of blackouts and load shedding. Consequently, this has affected in a negative way the economic activities of this nation such as low productivity in the production of goods and services making livelihood a difficult. Similarly, noneconomic activities such social interactions seem to be challenging due to lack of electricity. In this regard an investigation in determining new innovations towards electricity production remained one of the most important aspects in this county of Malawi. Method: This study was conducted in Chikwawa district, Malawi, to assess the feasibility of solar energy production. The methods used include temporal variability, correlation, trend, and spatial analysis to assess solar radiation, sunshine hours, and their distribution in the area. Result: As a result, the study was established with the purpose to assess feasible regions within the country of Malawi to innovate solar energy production to boost high levels of solar energy production. This study was conducted in the lower shire district and to be specific in Chikwawa district. The objectives of the feasibility in Chikwawa district included; assessing solar radiation and sunshine hours towards solar energy production, the spatial distribution of solar radiation and sunshine hours towards solar energy production, the trend of sunshine and solar radiation towards solar production and at the end to map the areas in Chikwawa District where solar energy production could be harnessed. Through the use of temporal variability, correlation analysis, trend analysis, and spatial analysis, the findings of this investigation established that harnessing solar energy is much more possible in areas of the lower shire which is the among others include Chikwawa district of Malawi as most areas currently in this region has less places with solar energy production but with high availability of solar radiation. Conclusion: For the fact that the findings reveal more feasible places to establish solar energy production, this study recommends commitment by government and private sector to greatly establish solar energy production units in this area whilst focusing on identifying other potential areas where solar energy production can be harnessed in Malawi. In this regard, this exposition has achieved its purpose of fostering renewable energy production through innovating and investing in solar energy production. Novelty/Originality of this study: This detailed spatial and temporal analysis study has identified optimal locations for solar energy production, providing a new approach to renewable energy planning in developing countries.

Does energy innovation heterogeneously affect renewable energy production?

Achieving long-term sustainable development is a critical global imperative, and the adoption of renewable energy sources plays a pivotal role in this endeavor, aided by the advancements of the Fourth Industrial Revolution. As a result, energy innovation has emerged as a crucial factor in realizing sustainable development goals. This study utilizes panel quantile regression analysis to investigate the relationship between energy innovation and renewable energy production in the Middle East and North Africa (MENA) region from 1985 to 2019. The findings suggest that energy innovation can effectively enhance renewable energy production, particularly in countries with higher proportions of renewable energy generation, such as Egypt, Morocco, and Tunisia. However, countries like Saudi Arabia, which have lower ratios of renewable energy production, may not experience a significant impact from energy innovation. Consequently, the study recommends implementing systematic and integrated measures that focus on raising awareness and improving conditions for the adoption of renewable energy. These measures can drive the transition towards a more sustainable energy landscape in the MENA region. Policymakers should prioritize research and development investment and incentives in countries with higher levels of renewable energy generation, while simultaneously addressing barriers and fostering knowledge sharing between countries with differing levels of renewable energy production.

Exploring the complex interplay of green finance, business cycles, and energy development

Green finance has emerged as a contemporary mechanism to support investments in renewable energy, energy efficiency, and sustainable infrastructure projects. This study aims to provide empirical insights into the asymmetric influence of green finance and business cycle fluctuations on energy development in 60 developing countries from 2000 to 2021. Four aspects of energy development, including energy access, stability, efficiency, and production gap, are examined using panel quantile regression with additive fixed effects. The research findings demonstrate that green finance plays a significant role in fostering energy development, with varying effects across different quantiles of the distribution. Specifically, the results indicate that green finance supports energy access and stability, particularly during economic recession, low-income levels, and limited technological advancement. However, the impact of green finance on energy efficiency exhibits notable heterogeneity, contingent upon technological and periods of economic expansion. Achieving tangible improvements in energy efficiency necessitates a certain level of technological and economic development. Moreover, green finance shows a capacity to maintain an optimal level of energy production, particularly evident during economic expansion and for highly technologically developed countries. The impact of business cycle fluctuations varies across different quantile distributions of energy development indicators, predominantly exerting an inhibitory effect of economic recession. In light of these results, it is recommended that policies in developing countries be revised to enhance energy access, optimize energy production levels, and promote the cost-effectiveness of renewable energy in conjunction with green finance initiatives.

A novel trigeneration energy system with two modes of operation for thermal energy storage and hydrogen production

This article introduces a new trigeneration system designed to meet the escalating energy demands by harnessing solar energy. Notably, the system features dual-mode operation and integrates ultrasound technology for hydrogen production, enabling it to adapt to varying levels of energy production by seamlessly transitioning between two modes. Through comprehensive energy, exergy, and environmental analyses, this study evaluates the system's performance and its environmental advantages. The results demonstrate that the system achieves the energy and exergy efficiencies of 58.28 % and 76.75 %, respectively. Moreover, it demonstrates that, under sunlight conditions, the system can produce hydrogen at a rate of 1 kg/h and deliver a power output of 1957 kW. During the periods utilizing a thermal energy storage option, the system is capable of generating hydrogen at 0.8 kg/h and an electrical power output of 1481.2 kW. The environmental analysis indicates that the system is eco-friendly, with the potential to reduce carbon dioxide emissions by 4.54 kg/kWh. These results underscore the system's efficiency and its contribution toward a more sustainable and environmentally friendly energy future.

Effect of cavitation treatment of coal-water slurries on a droplet average size in a jet

Relevance. Transition to environmentally friendly energy technologies, due to modern requirements for environmental protection, involves the search and creation of new energy sources, including fuels. One of the ways to meet these requirements and maintain the same level of energy production by thermal power plants is the transition to multicomponent fuels. The most promising and affordable boiler fuels from the point of view of energy, ecology and economy are coal-water slurries. In this regard, the study of the properties and characteristics of such fuels is relevant in many countries. Aim. Experimental studies of the effect of the coal-water fuel cavitation treatment duration on a droplet average size in a jet after spraying with a pneumatic nozzle and substantiation of the efficiency of such approach for practical application. Object. Experimental studies were carried out with coal-water slurries based on long-flame coal (D grade) with addition of 10 and 20 wt % by weight of pyrogenetic liquid. A slurry, consisting of just coal and water, without the addition of pyrogenetic liquid, was used as a reference sample. Method. The coal-water slurries were prepared in a rotary hydrodynamic cavitation generator. A pneumatic nozzle with external mixing was used to spray the coal-water slurries. The average size of fuel droplets after spraying was determined using the Interferometric Particle Imaging method. Results. Experiments on the preparation of coal-water slurries with pyrogenetic liquid showed an increase in the dynamic viscosity of the fuel. An increase in the duration of treatment of the slurries in a rotary hydrodynamic cavitation generator reduced the viscosity by 54%. The average size of droplets in the jet was reduced by 22%.

A dynamic programming schedule trading off quality and stability in task allocation for energy-neutral Internet of Things devices harvesting solar energy

Energy neutrality in an energy harvesting Internet of Things (IoT) device ensures continuous operation of the device by trading performance with energy consumption, and a way to achieve this is by adopting a task-based model. In this model, the device embeds several alternative tasks with different ratio energy-cost/quality and a scheduler that, depending on the current energy production and battery level, runs at any time the best task to maximize the performance while guaranteeing energy neutrality. In this context, this work proposes a novel scheduling algorithm that takes into account also the stability of the device, by minimizing the leaps of quality between two consecutive tasks in the scheduling. We show by simulation and by experiments on a low-power IoT platform that the proposed algorithm greatly improves the stability of the device with respect to the state-of-the-art algorithms, with a marginal worsening of the overall quality of the tasks executed.

Solar Panels Produced Electricity Impact on Electricity Network

Historically, during the creation of a unified energy system, base load power plants were constructed in Estonia (shale power plants) and Lithuania (the Ignalina nuclear power plant and the Elektrenai power plant). In Latvia, the Daugava hydropower plants were designed for peak, half-peak and emergency modes in which it is possible to relatively quickly and simply implement the sudden increase or decrease of capacity according to necessity. Neither coal nor shale power plants allow such sudden change of generation capacity due to a technologically more complex process. Latvian largest electricity supplier JSC "Latvenergo" 72% of the electricity - 3.6 TWh (2012) produced from renewable and environmentally friendly energy sources [1]. JSC “Latvenergo” uses two types of energy resources in the energy generation process: renewable energy sources in hydropower plants and in biomass and wind power plants; highly efficient cogeneration in gas-fired power plants. Latvia already is one of the greener countries in the Europe in accordance with high level of energy production from RES and future strategies for energy sector development also include RES use for heat and electricity production. The Energy Strategy 2030 sets the following objectives of the energy policy: – Competitive economy – balanced, efficient, economically, socially, and ecologically justified energy policy based on market principles ensuring further development of the economy, competitiveness in the region and world; its – Sustainable energy – reduced dependency on imported energy resources, new and efficient technologies for the use of renewable resources are encouraged, measures to implemented; improve energy efficiency are – Secure supply – stable energy supply and developed infrastructure provided to energy users.

Prototype Development for Solar Energy Tracking Based on Arduino in QUEST Campus Larkana

The utilization of solar energy has become increasingly popular due to its renewable and sustainable nature. However, one of the primary challenges in solar energy harvesting is the optimization of the amount of energy that can be captured from the sun. The implementation of solar trackers is an effective solution that enables the automatic adjustment of the solar panel's position to face the sun throughout the day. In this project, an Arduino-based solar tracker prototype was designed and implemented to optimize the solar energy harvesting process. The system employs Light-Dependent Resistors (LDRs) to detect sunlight intensity and a servo motor to adjust the position of the solar panel accordingly. The system was programmed using the Arduino programming language and was tested using a small-scale solar panel. The increasing demand for cost-effective and easy-to-install renewable energy systems has led to a growing interest in photovoltaic solar energy for residential use. To optimize energy production, a two-axis photovoltaic solar tracker that orients the solar panel toward the maximum solar radiation is proposed in this study. The use of Free Computer Aided Design (CAD) 0.15 for the prototype's design, combined with Arduino technology, provides an affordable solution for mounting the solar tracker on flat roofs and other horizontal building elements. The performance of the solar tracker was evaluated under various testing conditions, showcasing an enhanced level of accuracy and energy production when compared to traditional fixed systems. The prototype's successful demonstration represents a significant advancement in the field, providing a practical solution for small-scale and residential solar energy applications. This research prototype was developed and installed on the roof of the Electrical department of QUEST, Campus Larkana, and validated through simulation results.

Africa’s Contribution to the Discourse on Environment, Renewable Energy and Sustainable Development

Renewable energy and sustainability are vital for the development of Africa. Social welfare and economic growth are contingent on meeting the consumption needs and production targets using modern, sustainable energy sources. This is particularly crucial to Africans, given that the continent is home to the least developed countries globally, and the population with access to electricity is less than half. Colonialism has undoubtedly impacted and shaped our energy and, consequently, environmental transitions by allowing the traumatic exploitation of natural habitats and plundering of minerals, all at the service of the formation of their early modern states and the growth of capitalism. This status has been greased and maintained using neo-colonial and imperial tools such as the illusion of ‘free trade’, structural adjustment programs and crippling debt. All these are aimed at staging a stagnation of economic development that translates to underdeveloped industries and inefficient energy production levels. The domino effect of this is also seen in the current environmental crisis, which is essentially the biological destruction of wildlife and marine life while posing grave dangers to the continuation of African civilisation. This article explores the impact of imperialism and traces of neo-colonialism on the energy sector in Africa and how Africa can push for renewable energy by building its own industries and utilising abundant resources to chart a path towards sustainability. It dives into the depths of already established renewable energy programs that the states ought to accelerate to enable them to reach wider populations, as well as the mutually beneficial relationship we have between renewable energy and the environment.

Improved Vanadium Redox Flow Battery Performance through a Pulsating Electrolyte Flow Regime

The increase in emissions of greenhouse gases and their environmental impact lead to a transition from primarily fossil fuel-based energy sources to renewable and eco-friendly ones, such as solar panels and wind turbines. However, these sources are intermittent, resulting in fluctuating energy production levels that require buffering, which poses significant challenges in matching production-consumption profiles. [1,2] In order to stabilise the grid and reduce dependency on fossil fuels, integrating electrical energy carriers into a smart grid to store excess energy produced during peak periods and employ it during periods of low production is a potential solution. Redox flow batteries hold promise in this regard, as the storage capacity can be decoupled from the battery size, enabling capacity to be scaled independently of power output by increasing the volume of the electrolyte. [3] In contrast to conventional secondary battery types, such as lead-acid or lithium-ion batteries, the electrolyte in a redox flow battery is non-stationary, inducing convective mass transport effects that are critical for achieving a high power output.In this work we introduced pulsations to the electrolyte flow of an all-vanadium redox flow battery, leading to a reduced stagnant boundary layer attributed to shear forces. Previously, Pérez-Gallent et al. demonstrated that the conversion can be increased by a factor of two while selectivity gains of 15-20% can be made in a electrolyser by introducing a pulsating flow. [4] Furthermore, Vranckaert et al. studied a pulsating flow combined with pillar field electrodes, using the well-known ferri-ferrocyanide redox couple, and concluded that the average limiting current density can be increased fourfold compared to working with a conventional steady state flow regime. [5] Overall, a pulsating flow behaviour yields an enhanced mass transfer of electroactive species by increasing the local velocity through pulsations. The net residence time of the reactants remains unchanged since the pulsating flow has no influence on the overall flow velocity. However, the resulting improvement of mass transfer leads to an increase in conversion. As it is clear that mass transfer enhancement strategies open the door for more efficient systems, our work will for the first time focus on the influence of a pulsating electrolyte flow on the redox flow battery performance. The results show a significant improvement: the discharge capacity at 100 mA/cm2 increased by 38.7% when applying a pulse with pulse amplitude (PA) 0.4ml and pulse frequency (PF) 2.4 Hz at a flow rate of 5 ml/min (Figure 1 A). Furthermore, this 38.7% increase in discharge capacity surpassed the performance achieved at a constant steady-state flow of 25 ml/min. Therefore, a fivefold reduction of the net flow rate is possible without performance losses, decreasing necessary pumping costs. When regarding the stability of an all-vanadium redox flow battery operated with a pulsating electrolyte flow initial fluctuations of the current efficiency (CE), voltage efficiency (VE) and energy efficiency (EE) were recorded. However, the efficiencies became stable at 98.4%, 70.5% and 69.4% respectively, showing no decline over time (Figure 1 B). This novel and improved redox flow battery system allows to take the next step towards integrating electrical energy carriers into a smart grid suitable for renewable and green energy sources.[1] P. D. Lund, J. Lindgren, J. Mikkola, J. Salpakari, Renew. Sustain. Energy Rev. 2015, 45, 785–807.[2] H. Kondziella, T. Bruckner, Renew. Sustain. Energy Rev. 2016, 53, 10–22.[3] E. Sánchez-Díez, E. Ventosa, M. Guarnieri, A. Trovò, C. Flox, R. Marcilla, F. Soavi, P. Mazur, E. Aranzabe, R. Ferret, J. Power Sources 2021, 481, 228804.[4] E. Pérez-Gallent, C. Sánchez-Martínez, L. F. G. Geers, S. Turk, R. Latsuzbaia, E. L. V. Goetheer, Ind. Eng. Chem. Res. 2020, 59, 5648–5656.[5] M. Vranckaert, H. P. L. Gemoets, R. Dangreau, K. Van Aken, T. Breugelmans, J. Hereijgers, Electrochim. Acta 2022, 436, 141435. Figure 1

A critical review of PV systems’ faults with the relevant detection methods

PhotoVoltaic (PV) systems are often subjected to operational faults which negatively affect their performance. Corresponding to different types and natures, such faults prevent the PV systems from achieving their nominal power output and attaining the required level of energy production. Regarding the operational optimization of PV systems, this paper aims primarily at surveying and categorizing different types of PV faults, classified as electrical, internal, and external, where each is thoroughly investigated: internal faults occur at the PV cellular level, and can either be short circuit, open circuit, bridging, or bypass diode faults. External faults on the other side are mainly classified as temporary (i.e., clouds shading, snowstorms, etc.) or permanent (e.g., glass breakage, frame defects, etc.) mismatch faults. Lastly, electrical faults involve common circuitry problems, such as short circuits (e.g., line to ground, line to line, etc.), power processing units’ faults (e.g., inverter faults), and arc faults. As for the detection methods, six major fault detection methods are investigated for the AC side of the PV system with twenty-nine total AC based fault detection methods. On the other hand, eleven major fault detection methods are surveyed for the DC side of PV systems with seventy-three total DC based fault detection methods. The investigated methods are critically analyzed, and compared relevantly to each other, within the mutual sub-sets. The resulting tabulated comparative data assessments for PV faults (i.e., cause-effect relationships, impact on the PV system performance), as well as for faults detection methods (i.e., priority for application, etc.) compose a rich background for related PV systems’ performance security fields, where a nexus future work is also suggested.

What level of renewable energy production will reduce ecological footprint without compromising trade? Evidence from Shanghai Cooperation Organization nations.

In order to decarbonize the global economy and reduce environmental degradation, it has become necessary to switch from using fossil fuels to renewable energy. However, a net zero global economy cannot be achieved without understanding the total renewable energy generation threshold and associated investment amount. This study estimates the renewable energy generation threshold to mitigate environmental degradation using data from 2003 to 2019 while focusing on Shanghai Cooperation Organization (SCO) nations. A panel fully modified model and the eight permanent nations of the SCO are employed. Our results show that while trade openness, foreign direct investment, and economic activities positively drive environmental degradation, renewable energy generation is a negative driver, and population has no relationship with environmental degradation. The threshold analysis shows that SCO nations need to increase their renewable energy generation from the current average of 2.403 to 7.737. Policy recommendation regarding how these nations can raise this money has been provided.

The Impact of Tourism on Energy Consumption: A Sectoral Analysis for the Most Visited Countries in the World

Tourist activity has strategic importance in the global economy. Nevertheless, the tourism activities are linked to increased emissions, due to the sector’s energy intensity, especially in the transport and commercial sectors. The aim of this study is to analyze the relationship between final energy consumption in the whole economy, the transport, commercial and public services sectors, and the tourist activity in the 15 countries with the highest number of international tourist arrivals in the world, in 2000–2019 period. The Energy–Environment Kuznets Curve (EKC) hypothesis extended with tourism has been tested. Obtained results show non-linear relationships between energy consumption and production levels. There is evidence in favor of the energy EKC hypothesis, and in favor of an inverted N-shaped relationship for transport and commercial and public services sectors. The results also show a positive, increasing relationship between energy consumption and tourist arrivals for the whole economy. However, there is some evidence of the tourism energy EKC hypothesis when considering the transport, commercial and public services sectors. Therefore, economies of scale are observed in these sectors. Accordingly, it is highly advisable to increase the economies of scale, coupled with a greater awareness on the use of renewable energy. Negative relationships are found between energy consumption and tourism receipts. Therefore, it is advisable to establish policies that encourage high quality tourism to control the economy’s energy consumption.

Exploring the potential of concentrating solar power technologies for vertical farming in arid regions: The case of Western Iraq

Indoor vertical farming can address future food insecurity by reducing land use and environmental dependence positively mitigating the environmental impacts associated with conventional agriculture. However, its high energy consumption and environmental impact raise concerns. This paper explores the use of Concentrating Solar Power (CSP) to power vertical farming in Iraq's arid regions, using abundant solar resources to reduce environmental impact and energy costs. The study evaluates the feasibility and benefits of integrating CSP technologies into sustainable agricultural practices, considering factors like implementation costs, energy production, and water usage. The study utilized the system advisor model (SAM) to carry out the techno-economic assessment by relocating existing commercial CSP plant in Seville, Spain to six Iraqi locations, following a comprehensive technical site assessment. The energy production level, capacity factor (CF), and levelized cost of electricity (LCOE) of the initial Spanish plant were lower than five of the six selected locations. Haditha and Ar Rutbha cities have the highest annual energy output, 123 GWh and 122 GWh, respectively, surpassing Seville's original plant output, which at 110 GWh performed less than Iraq locations. Next, comparisons are made between conventional farming and vertical farming (VF) cultivation. The study focuses on Romaine lettuce as the benchmark crop due to its prevalence in vertical farms and its suitability for arid climates. VF shows the potential to achieve yields between 41 and 68 kg/m2/y, 63 to 104 times higher than conventional farming in Western Iraq. VF's year-round cultivation with artificial lighting results in 83 times greater energy demands, requiring 25 kWh/kg/y. The findings emphasize the potential of CSP technologies to support sustainable agriculture in Iraq's arid regions. These findings demonstrate the possibility of utilizing solar power for sustainable agriculture in Iraq, offering valuable insights for policymakers and stakeholders seeking cost-effective and energy-efficient solutions.

Hybrid wave/current energy harvesting with a flexible piezoelectric plate

We investigate the dynamics and energy production capability of a flexible piezoelectric plate submerged close to the free surface and exposed to incident head gravity waves and current. A theoretical model is derived in which the flag and its wake are represented with a vortex line while the body of the fluid is considered to be inviscid. The model is employed to describe the hydrodynamic interactions between a flexible plate, its wake, gravity incident waves and the current. The model reveals two distinct vibration states of a piezoelectric device corresponding to almost similar optimal energy production levels. The first is associated with the cantilever fluttering mode of the plate, with limited dependency on the plate's flexibility across different Froude numbers and incoming wave frequencies. The other resembles the flow-induced flapping mode in more flexible plates, with the energy output showing a higher dependency on plate flexibility. The concurrent existence of these two energetic modes allows adjustment of the plate length to consistently achieve the maximum energy production level across different flow conditions. The role of the Froude number of the system's responses is explored and correlated to the appearance of gravity wave groups on the surface, each propagating with a different wavenumber. It is shown that a submergence depth of less than half of the body length is required to reach a high energetic condition in subcritical and critical flows. Finally, the optimal inductive and resistive values are related to proper matching between flow, mechanical and electrical time scales.

Knockout of Tmlhe in mice is not associated with autism spectrum disorder phenotypes or motor dysfunction despite low carnitine levels

Deletion of exon 2 of the trimethyllysine hydroxylase epsilon (TMLHE) gene was identified in probands with autism spectrum disorder (ASD). TMLHE encodes the first enzyme in carnitine biosynthesis, N6-trimethyllysine dioxygenase (TMLD). Researchers have suggested that carnitine depletion could be important for the development of ASD and cognitive, locomotor and social dysfunctions, but previous findings have been inconclusive regarding the specific role of endogenous carnitine. We developed a mouse knockout model with constitutive TMLD enzyme inactivation that exhibited a significant decrease in the carnitine by more than 90% compared to wild-type (WT) mice. However, we did not observe any significant social, cognitive, or repetitive-behavior changes associated with ASD in the knockout mice; muscle strength and coordination were also not affected. In addition, the life expectancy of knockout mice was similar to that of WT mice. In conclusion, knockout of Tmlh in mice does not induce an ASD phenotype or motor dysfunction despite extremely low carnitine and gamma-butyrobetaine concentrations. Moreover, inactivation of TMLD does not induce a phenotype similar to previously described primary carnitine deficiency; indeed, our results showed that low levels of carnitine sustained adequate energy production, muscle function and social behavior in mice.

Lipid A Modification and Metabolic Adaptation in Polymyxin-Resistant, New Delhi Metallo-β-Lactamase-Producing Klebsiella pneumoniae.

Polymyxins are last-line antibiotics employed against multidrug-resistant (MDR) Klebsiella pneumoniae. Worryingly, polymyxin resistance is rapidly on the rise globally. Polymyxins initially target lipid A of lipopolysaccharides (LPSs) in the cell outer membrane (OM), causing disorganization and cell lysis. While most studies focus on how genetic variations confer polymyxin resistance, the mechanisms of membrane remodeling and metabolic changes in polymyxin-resistant strains remain unclear, thus hampering the development of effective therapies to treat severe K. pneumoniae infections. In the present study, lipid A profiling, OM lipidomics, genomics, and metabolomics were integrated to elucidate the global mechanisms of polymyxin resistance and metabolic adaptation in a polymyxin-resistant strain (strain S01R; MIC of >128 mg/L) obtained from K. pneumoniae strain S01, a polymyxin-susceptible (MIC of 2 mg/L), New Delhi metallo-β-lactamase (NDM)-producing MDR clinical isolate. Genomic analysis revealed a novel in-frame deletion at position V258 of PhoQ in S01R, potentially leading to lipid A modification with 4-amino-4-deoxy-l-arabinose (L-Ara4N) despite the absence of polymyxin B. Comparative metabolomic analysis revealed slightly elevated levels of energy production and amino acid metabolism in S01R compared to their levels in S01. Exposure to polymyxin B (4 mg/L for S01 and 512 mg/L for S01R) substantially altered energy, nucleotide, and amino acid metabolism and resulted in greater accumulation of lipids in both strains. Furthermore, the change induced by polymyxin B treatment was dramatic at both 1 and 4h in S01 but only significant at 4h in S01R. Overall, profound metabolic adaptation was observed in S01R following polymyxin B treatment. These findings contribute to our understanding of polymyxin resistance mechanisms in problematic NDM-producing K. pneumoniae strains and may facilitate the discovery of novel therapeutic targets. IMPORTANCE Antimicrobial resistance (AMR) is a major threat to global health. The emergence of resistance to the polymyxins that are the last line of defense in so-called Gram-negative "superbugs" has further increased the urgency to develop novel therapies. There are frequent outbreaks of K. pneumoniae infections in hospitals being reported, and polymyxin usage is increasing remarkably. Importantly, the polymyxin-resistant K. pneumoniae strains are imposing more severe consequences to health systems. Using metabolomics, lipid A profiling, and outer membrane lipidomics, our findings reveal (i) changes in the pentose phosphate pathway and amino acid and nucleotide metabolism in a susceptible strain following polymyxin treatment and (ii) how cellular metabolism, lipid A modification, and outer membrane remodeling were altered in K. pneumoniae following the acquisition of polymyxin resistance. Our study provides, for the first time, mechanistic insights into metabolic responses to polymyxin treatment in a multidrug-resistant, NDM-producing K. pneumoniae clinical isolate with acquired polymyxin resistance. Overall, these results will assist in identifying new therapeutic targets to combat and prevent polymyxin resistance.

Green hydrogen production ensemble forecasting based on hybrid dynamic optimization algorithm

Solar-powered water electrolysis can produce clean hydrogen for sustainable energy systems. Accurate solar energy generation forecasts are necessary for system operation and planning. Al-Biruni Earth Radius (BER) and Particle Swarm Optimization (PSO) are used in this paper to ensemble forecast solar hydrogen generation. The suggested method optimizes the dynamic hyperparameters of the deep learning model of recurrent neural network (RNN) using the BER metaheuristic search optimization algorithm and PSO algorithm. We used data from the HI-SEAS weather station in Hawaii for 4 months (September through December 2016). We will forecast the level of solar energy production next season in our simulations and compare our results to those of other forecasting approaches. Regarding accuracy, resilience, and computational economy, the results show that the BER-PSO-RNN algorithm has great potential as a useful tool for ensemble forecasting of solar hydrogen generation, which has important ramifications for the planning and execution of such systems. The accuracy of the proposed algorithm is confirmed by two statistical analysis tests, such as Wilcoxon’s rank-sum and one-way analysis of variance (ANOVA). With the use of the proposed BER-PSO-RNN algorithm that excels in processing and forecasting time-series data, we discovered that with the proposed algorithm, the Solar System could produce, on average, 0.622 kg/day of hydrogen during the season in comparison with other algorithms.