Low Energy Research Articles

Synthesis and pharmacological activity of various organic and inorganic salts of phenyl derivatives of imidazobenzimidazole

Introduction: The creation of new opioid analgesics that are devoid of the main undesirable effects – euphoria, respiratory depression, tolerance – is an important task for the treatment of pain syndrome. Eighteen salts of 9-pyrrolidinoethyl-(1a), 9-piperidinoethyl-(1b), and 9-morpholinoethyl-2-(4-fluorophenyl)benzo[d]imidazo[1,2-a]imidazole (1c) were synthesized and tested for kappa agonist and analgesic activity. Materials and Methods: Specific analgesic activity studies were conducted using models of nociceptive pain in the “Hot/Cold-plate” and ”Plantar Test” tests, and in neuropathic pain against the background of sciatic nerve ligation. The relationship between the physicochemical and pharmacological properties of the compounds was studied in silico using quantum chemistry methods and artificial neural network technology. Results: The most active compound identified was 4-(2-(2-(4-fluorophenyl)-benzo[d]imidazo[1,2-a]imidazol-9-yl)ethyl)morpholine dihydrochloride (1c.2HCl). EC50, acute toxicity, and conditional therapeutic index values were calculated, which were 38.8 times superior to the kappa agonist U50488. It was established that compound 1c.2HCl exhibits a dose-dependent analgesic effect in the “Hot/Cold-plate” test, which is six times superior to that of butorphanol, maintaining a statistically significant effect for six hours in the “Plantar test” and without causing the formation of tolerance with a ten-day administration. In models of neuropathic pain syndrome, 1c.2HCl with a fourteen-day administration significantly reduced tactile and cold allodynia by three and 1.6 times, respectively, and was not inferior in activity to gabapentin. The kappa-opioidergic mechanism of the antinociceptive action of 1c.2HCl compound was confirmed. Quantum chemistry methods and artificial neural network technologies have shown that the high level of kappa-opioid agonist activity of hydrochlorides, in contrast to other salts, results in lower total energy production; therefore, there is a significant increase in energy during the formation of a salt supramolecular complex. Conclusion: The most active compound was identified – 1c.2HCl, for which kappa-opioid activity in vitro and analgesic properties were revealed in various in vivo models. It has been shown that the compound does not cause the formation of tolerance and is not toxic.

The Cointegration Between Energy Subsidy and Energy Accessibility in Eastern Africa Countries

Despite the significant potential, the energy industry in East Africa remains largely underdeveloped, with minimal modern energy access, low per capita consumption, and heavy reliance on biomass energy, which makes up over 90% of the region’s energy consumption. Less than 1% of rural areas have access to electricity. Introduction of subsidies on energy influences energy accessibility. The study found it clear that subsidies slightly improved energy accessibility in Eastern African countries in the long run. This can be explained by the fact that energy subsidies often result in lower prices for energy consumers. This makes energy more affordable for households, particularly those with lower incomes. Lower energy prices reduce the financial burden of meeting energy needs, making it easier for individuals and families to access essential energy services such as electricity, heating, and cooking. Lower energy prices due to subsidies can lead to increased energy consumption. It is therefore the responsibility of each member state to encourage the adoption of renewable energy sources by providing subsidies and incentives for renewable energy technologies such as solar panels, wind turbines, and energy-efficient appliances. Subsidizing renewable energy reduces reliance on fossil fuels, mitigates environmental impacts, and promotes sustainable energy practices.

Implementing AI on low-power embedded devices for digital water meter identification and data transfer via lora network

This study introduces an artificial intelligence system implemented on the ESP32-CAM platform, aimed at conducting optical character recognition (OCR) on water meters. Leveraging LoRa technology for data transmission ensures efficient energy utilization and convenient long-range communication capabilities. The system achieves an impressive accuracy rate of 98.2% in identifying water meter readings, showcasing its reliability. Proposed as a feasible solution, it offers the advantages of low energy consumption, cost-effectiveness, and flexibility in widespread deployment, particularly leveraging existing water meter infrastructure. Thus, this research presents a promising choice for various applications beyond merely reading water meter readings. Its efficient and accurate OCR functionality makes it suitable for diverse scenarios, ranging from smart city initiatives to industrial automation processes. With its ability to integrate seamlessly into existing infrastructure and deliver reliable results, this system stands poised to revolutionize OCR applications in various domains, contributing to enhanced efficiency and productivity.

Novel Antioxidant Self-Assembled Peptides Extracted from Azumapecten farreri Meat: In Vitro- and In Silico-Assisted Identification

Previous studies have found that the self-assembled supramolecules of Azumapecten farreri meat peptides have antioxidant effects. Therefore, this study aims to isolate and identify novel antioxidant peptides with self-assembly characteristics and analyze their structure–activity relationship through molecular docking and molecular dynamics simulation. The in vitro results show that as the purification steps increased, the antioxidant activity of peptides became stronger. Additionally, the purification step did not affect its pH-responsive self-assembly. Using LC-MS/MS, 298 peptide sequences were identified from the purified fraction PF1, and 12 safe and antioxidant-active peptides were acquired through in silico screening. The molecular docking results show that they had good binding interactions with key antioxidant-related protein ligands (KEAP1 (Kelch-like ECH-associated protein 1) and MPO (myeloperoxidase)). The peptide QPPALNDSYLYGPQ, with the lowest docking energy, was selected for a 100 ns molecular dynamics simulation. The results show that the peptide QPPALNDSYLYGPQ exhibited excellent stability when docked with KEAP1 and MPO, thus exerting antioxidant effects by regulating the KEAP1-NRF2 pathway and inhibiting MPO activity. This study further validates the antioxidant and self-assembling properties of the self-assembled supramolecules of Azumapecten farreri meat peptide and shows its potential for developing new, effective, and stable antioxidants.

Li-decorated B12C6N6 hybrid nanocage for sensing Cl2, COCl2, H2S and NH3 gas molecules

We examined the gas sensing abilities of Li-decorated B12C6N6 (B12C6N6Li) hybrid nanocage, introducing B12C6N6 for the first time in sensing applications. The toxic gas molecules like Cl2, COCl2, H2S, and NH3 were considered. The B12C6N6 nanocage with C2V symmetry displayed the lowest energy among its isomers. Li exhibited stronger anchoring above B3C2N ring compared to B2C2, B2N2, and B3CN2 rings of B12C6N6 nanocage, displaying a binding energy of −3.30 eV. Li decoration resulted in asymmetric spin-up and spin-down states near Fermi level, indicating magnetic nature of complexes. B12C6N6, an electron-deficient nanocage, displayed charge transfer from Li atom to the nanocage. Substantial changes in electronic states occurred following the adsorption of Cl2 and COCl2 molecules. COCl2, H2S, and NH3 adsorption is thermodynamically favourable over a wide temperature and pressure range, while Cl2 adsorption is favourable only within a confined range. Earlier findings indicate dissociative adsorption of Cl2 on nanocages rendering the substrate to be non-reusable. B12C6N6Li considered here is superior over other nanocages as Cl2 adsorbs in molecular form while B12C6N6Li also demonstrates significant sensitivity. B12C6N6Li nanocage is unsuitable for sensing H2S and NH3 gas molecules but holds promise as a potential candidate for sensing Cl2 and COCl2 gas molecules.

Monte Carlo multiscale modelling of photon and proton distribution in heterogenous tissue

Enhancements in radiotherapy treatment outcomes can be realised by minimising uncertainties in dose distribution. Current treatment planning struggles to accurately calculate dose distribution in complex heterogeneous areas, thereby increasing the uncertainty associated with dose distribution. This research focuses on studying microscopic dose distribution in the temporal bone and cochlea. This study utilised an open-access DICOM format dataset for resected temporal bone and cochlea tissue, employing the FLUKA MC code to simulate potential high-dose scenarios in volume-modulated arc therapy using the FLOOD option. Simulations were conducted at 23 photon and proton energy levels, ranging from 0.055 to 5.5 MeV for photons and 37.59–124.83 MeV for protons, to calculate dose distributions. The largest proportion of the dose (48.8%) was deposited in high-density bone at photon energies between 0.055 and 0.09 MeV. Above 0.125 MeV, a notable shift in dose distribution to low-density tissues occurred, reaching a deposition of 53%. In intermediate-density soft bone, dose distribution was 26.4% at 0.07 MeV and decreased to 19.7% at 2.5 MeV, reflecting a 29% difference in dose distribution across the energy spectrum. In proton simulations, dose distribution at low energy (37.59 MeV) revealed no significant changes across low (54.86%), intermediate (19.75%), and high-density (25.39%) areas. Similar patterns were observed at high energy (124.83 MeV), with dose distributions of 54.21% in low-, 19.79% in intermediate-, and 26% in high-density areas. The simulations demonstrated that proton dose distribution was not significantly influenced by tissue heterogeneity in micro-CT data. The photoelectric effect at low energy levels contributed minimally to the dose in soft bone, favouring higher deposition in high-density bone, despite a lower weighting factor at low energies compared with high energies.

Theoretical evaluation of M/H-magadiite and Al modified M/H-[Al]-magadiites single-atom catalysts (M = Ag, Au, Pd, and Pt)

This work intends to simulate the interaction of metal single-atom(s) supported on surfaces of H-magadiite (H4Si14O30) and Al substituted H-[Al]-magadiites (H5AlSi13O30), hereafter called M/H-magadiite and M/H-[Al]-magadiite (M = Ag, Au, Pt, Pd), using DFT calculations (PBE and PBE-D3 functionals). Three distinct positions were defined in all surfaces to optimize each simulated model: “hydroxyl”, “edge” and “cavity”. The Au/H-magadiite and Ag/H-magadiite models were more stable at the “hydroxyl” sites. Meanwhile, in the aluminated surfaces, the presence of an extra hydrogen atom (here called Hextra, located in the “edge” region) was responsible for a more stable situation of these metal atoms. On the other hand, the Pd and Pt single-atoms present in H-magadiite and H-[Al]-magadiites showed greater interaction with all the sites, compared to the Au- and Ag- models. Based on the binding energies and other electronic calculations, the aluminol site at H-[Al]-magadiites has the best capacity to support metal species. For example, the Pt/H-[Al]-magadiite showed the lowest binding energy (-2.64 eV for PBE and -2.93 eV for PBE-D3), the strongest charge interaction and the smallest Pt – Hextra distance (1.55 Å). The migration barriers (PBE) in Ag/H-magadiite, Au/H-magadiite, and Pd/H-magadiite were lower than 21.50 kJ·mol−1, suggesting the high possibility of metal sintering. For all the cases, the PBE-D3 overestimated the barriers. Contrarily, the Pt/H-magadiite structures stabilized in the “cavity” region, inside the silicon rings of the silicate, and presented a migration barrier greater than 200 kJ·mol−1. These calculations offered the first indications of the behavior of single-atoms, which will serve as the basis for a broader description, in future works, of the migration of metal species in the Al-models simulated here, as well as for modeling single-atom catalysts that can be used in stable conditions.

Cumulative Dose from Recurrent CT Scans: Exploring the DNA Damage Response in Human Non-Transformed Cells

Recurrent computed tomography (CT) examination has become a common diagnostic procedure for several diseases and injuries. Though each singular CT scan exposes individuals at low doses of low linear energy transfer (LET) radiation, the cumulative dose received from recurrent CT scans poses an increasing concern for potential health risks. Here, we evaluated the biological effects of recurrent CT scans on the DNA damage response (DDR) in human fibroblasts and retinal pigment epithelial cells maintained in culture for five months and subjected to four CT scans, one every four weeks. DDR kinetics and eventual accumulation of persistent-radiation-induced foci (P-RIF) were assessed by combined immunofluorescence for γH2AX and 53BP1, i.e., γH2AX/53BP1 foci. We found that CT scan repetitions significantly increased both the number and size of γH2AX/53BP1 foci. In particular, after the third CT scan, we observed the appearance of giant foci that might result from the overlapping of individual small foci and that do not associate with irreversible growth arrest, as shown by DNA replication in the foci-carrying cells. Whether these giant foci represent coalescence of unrepaired DNA damage as reported following single exposition to high doses of high LET radiation is still unclear. However, morphologically, these giant foci resemble the recently described compartmentalization of damaged DNA that should facilitate the repair of DNA double-strand breaks but also increase the risk of chromosomal translocations. Overall, these results indicate that for a correct evaluation of the damage following recurrent CT examinations, it is necessary to consider the size and composition of the foci in addition to their number.

ZIF‐67 Derived Co‐LDH Nanocubes for Oxygen Evolution Reaction

AbstractTo address the substantial energy needs of the quickly evolving modern civilization, efforts are still needed to provide sustainable renewable energy sources. The electrocatalytic Oxygen evolution reaction (OER) is one of the essential technologies used in the various hydrogen production techniques. ZIF‐67 nanocubes (ZIF‐67 NCs) were synthesized in an aqueous solution and used as sacrificial templates. Cobalt nitrate hexahydrate was added under water bath conditions, resulting in the evolution of numerous small layered layers of cobalt hydroxide. This ultimately led to the formation of multilayered, three‐dimensionally crosslinked Co‐LDH with a porous networked cubic morphology. Hydrolysis of Co2+ at different concentrations produces different degrees of weak acidic environments, and the loose LDH on the cubic structure of the best catalyst, Co‐LDH‐1, exposes more active cobalt sites for the OER, which results in a high electrochemically active surface area, with an overpotential of 354 mV and a Tafel slope of 79.06 mV dec−1 at a current density of 10 mA cm−2, and good stability and low activation under alkaline condition also has good stability and low activation energy. It provides us an easy and practical plan for logically creating ZIF‐derived hydroxide materials, leading to the development of affordable and effective electrocatalysts.

Understanding the transformation mechanism of carbon species on different Nickle facets in CO2 reforming reaction

As human industry continues to develop, the concentration of greenhouse gases in the atmosphere continues to rise, causing certain impacts on human daily production and life. The dry reforming of methane (DRM) reaction can simultaneously utilize both CH4 and CO2 greenhouse gases, thus achieving the goal of turning waste into treasure. This study uses density functional theory (DFT) to simulate the transformation of carbon species on Ni(111), Ni(100), Ni(211), and Ni(311) facets from a kinetic perspective. These transformations include the carbon growth paths of CH*→C*+H* and C*+C*→C2, as well as the carbon elimination paths of CH*+O*→CHO*, C*+O*→CO*, and C*+CO2*→2CO*. Combining the energy barrier of different reaction paths, it is found that the Ni(111) facet exhibits the best ability to inhibit carbon growth and elimination, while the Ni(100) facet has weaker carbon elimination capability. Carbon is prone to deposition and difficult to be eliminated on step facets of Ni(211) and Ni(311). Furthermore, the present study investigates the binding relationship between different Ni facets and O*, finding that Ni(111) and Ni(311) facets have strong interaction ability with O*, which further explains the reason that the lower energy barrier of Ni(111) and Ni(311) facets in both CH*+O* and C*+O* reaction paths.

From Lab to Application: Challenges and Opportunities in Achieving Fast Charging with Polyanionic Cathodes for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs), recognized for balanced energy density and cost-effectiveness, are positioned as a promising complement to lithium-ion batteries (LIBs) and a substitute for lead-acid batteries, particularly in low-speed electric vehicles and large-scale energy storage. Despite their extensive potential, concerns about range anxiety due to lower energy density underscore the importance of fast-charging technologies, which drives the exploration of high-rate electrode materials. Polyanionic cathode materials are emerging as promising candidates in this regard. However, their intrinsic limitation in electronic conductivity poses challenges for synchronized electron and ion transport, hindering their suitability for fast-charging applications. This review provides a comprehensive analysis of sodium ion migration during charging/discharging, highlighting it as a critical rate-limiting step for fast charging. By delving into intrinsic dynamics, key factors that constrain fast-charging characteristics are identified and summarized. Innovative modification routes are then introduced, with a focus on shortening migration paths and increasing diffusion coefficients, providing detailed insights into feasible strategies. Moreover, the discussion extends beyond half cells to full cells, addressing challenges and opportunities in transitioning polyanionic materials from the laboratory to practical applications. This review aims to offer valuable insights into the development of high-rate polyanionic cathodes, acknowledging their pivotal role in advancing fast-charging SIBs.

Elucidating the potential of nitrogen-containing heterocyclic core-based non-fullerene acceptors for organic photovoltaic applications

Intramolecular noncovalent interactions are recognized as an efficient route to construct non-fused-core-based non-fullerene acceptors (NFAs) for efficient and cost-effective organic solar cells (OSCs). Herein, we engineered ten distinct structured NFAs molecules based on nitrogen-containing six-membered heterocycle cores. We incorporated various efficient functional groups into the synthetic reference molecule (RM) to design a new efficient series of NFAs (RM1-RM10). These materials are intensively investigated by performing advanced quantum chemical simulations, and the results are compared with those of synthetic RM molecules. We revealed the potential of these materials by investigating their optical, electronic, optoelectronic, and photovoltaic characteristics. By implementing various theoretical models, we explore the inner hidden potential of this designed series (RM1-RM10), such as density of state, transition density matrix, and electrostatic potential studies have been performed. Our applied theoretical modeling approach enables these photovoltaic materials (RM1-RM10) to have customized attributes by tuning their energy levels, binding energy, optical features, and also the photovoltaic characteristics of these materials. Newly developed molecules (RM1-RM10) show promising optoelectronic properties, including a lower energy gap (ranging from 1.81 eV to 1.63 eV) and an absorbed maximum absorption wavelength (760.36 nm), compared to the reference values, which have an energy gap of 1.81 eV and a wavelength of 684.16 nm. Moreover, to demonstrate the charge transfer behavior of these materials, a donor: acceptor (PTB7-Th:RM9) complex study is also performed to reveal the charge transfer phenomenon at the donor: acceptor interface. Therefore, our presented molecular modeling strategy holds significant potential for manufacturing materials with tailored qualities, which is crucial in advancing the organic photovoltaics field.

Multitargeted molecular docking and dynamics simulation of thymol-based chalcones against cancer protein markers: Synthesis, characterization, and computational study

Cancer prevention has become a significant public health concern in the 21st century, ranking as the second leading cause of global mortality following cardiovascular diseases. Despite prominent advancements in treatment, addressing cancer remains a substantial public health challenge, necessitating precise interventions tailored to diverse cancer types. The targeting of Epidermal Growth Factor Receptor (EGFR) has emerged as a fundamental strategy in modern cancer therapy due to its critical role in oncogenesis. Chalcones, a subclass of flavonoids, are promising anticancer agents due to their ability to target multiple cellular pathways implicated in cancer progression. The presence of α, β-unsaturated carbonyl moiety is a key structural feature attributed to their biological activity. This study presents an efficient synthesis approach for chalcone derivatives 4a-f designed from natural thymol. The synthesized compounds were further characterized by HRMS, 1H and 13C NMR spectral data, and further evaluated for in silico studies through molecular docking, molecular dynamic simulation, and ADMET screening. All the designed compounds 4a-f displayed favourable physicochemical properties and ADMET profiles. Molecular docking revealed favourable interactions between compounds 4a-f and the EGFR target protein. Compound 4d (p-nitro) and 4b (p-methyl) showed the more favourable docking score with low energy conformation (-8.02 kcal/mol), (-7.42 kcal/mol) respectively compared to the standard drug Gefitinib. Molecular dynamic simulations confirmed the stability of compounds 4d and 4b, exhibiting consistent structural stability in ligand-protein complexes throughout the 100 ns simulation. Acceptable RMSF values for amino acid residues indicated structural integrity and a stable protein-ligand interaction. The study identified 4d and 4b as promising leads for targeting EGFR.

Fast-Charging Anode Materials for Sodium-Ion Batteries.

Sodium-ion batteries (SIBs) have undergone rapid development as a complementary technology to lithium-ion batteries due to abundant sodium resources. However, the extended charging time and low energy density pose a significant challenge to the widespread use of SIBs in electric vehicles. To overcome this hurdle, there is considerable focus on developing fast-charging anode materials with rapid Na⁺ diffusion and superior reaction kinetics. Here, the key factors that limit the fast charging of anode materials are examined, which provides a comprehensive overview of the major advances and fast-charging characteristics across various anode materials. Specifically, it systematically dissects considerations to enhance the rate performance of anode materials, encompassing aspects such as porous engineering, electrolyte desolvation strategies, electrode/electrolyte interphase, electronic conductivity/ion diffusivity, and pseudocapacitive ion storage. Finally, the direction and prospects for developing fast-charging anode materials of SIBs are also proposed, aiming to provide a valuable reference for the further advancement of high-power SIBs.

Carbon Dioxide Capture: Current Status and Future Prospects

The surge in greenhouse gas emissions, predominantly in the form of carbon dioxide (CO2) spurred by the Industrial Revolution, has surpassed the critical threshold of 400 ppm, fueling global warming, ocean acidification, and climate change. To mitigate the adverse effects of these emissions and limit the global temperature rise to below 2 °C, the ambitious target of achieving net zero emissions by 2050 was established in the Paris Agreement. Current state-of-the-art technologies, such as amine scrubbing, remain problematic owing to their high energy requirements, susceptibility to corrosion, and other operational challenges. Owing to the lack of suitable technologies coupled with escalating energy demand, there is still a significant amount of carbon dioxide being released into the atmosphere. Accordingly, there is an urgent need for the development of alternative technologies that offer high efficiency, low energy consumption, cost-effective installation, and operation. In this review, we delve into the emerging technologies poised to address these challenges, evaluating their maturity levels in comparison to existing commercially available solutions. Furthermore, we provide a brief overview of ongoing efforts aimed at commercializing these innovative technologies.

Flux pinning dynamics in optimally proton irradiated REBCO coated conductors

Particle irradiation offers a route to incorporating additional flux pinning centres in high-temperature superconducting wires with minimal disruption to the pre-existing defect landscape, thereby further enhancing the critical current in a controllable fashion. This work is a comprehensive study of the fluence-dependence of proton irradiation using protons of two energies, 2.5 and 1.2 MeV, in enhancing the critical current performance in commercially available (Y,Dy)Ba2Cu3O7−δ coated conductors. A sequence of fluences covering the range from 1 × 1015 to 5 × 1016 protons cm−2 was used in the irradiation process to study the flux pinning in this material. The resulting samples were characterized using field angle-dependent transport critical current measurements over a range of temperatures from 20 K to 77.5 K and magnetic fields up to 8 T, thus covering the wide range of operating conditions. Optimisation of fluence for highest performance at each energy resulted in a similar level of isotropic critical current enhancement, a factor 2.6 improvement at 20 K and 8 T, but with a significant difference in the optimised fluence in each case. The lower energy 1.2 MeV protons produce this enhancement at a three-fold lower fluence compared to 2.5 MeV protons, a result of their higher electronic energy loss. The different samples are analysed within the framework of the maximum entropy model, helping to understand the vortex dynamics before and after irradiation.

Low Energy (< 10 eV) Electron Collision with Benzonitrile-CCl4 Admixture: A Combined Theoretical and Experimental Study.

Benzonitrile (BZN) and carbon tetrachloride (CCl4) are versatile solvents used as a precursor for the synthesis of many products. As multi-usage molecules, these compounds may be involved in sustainable chemistry processes such as the cold plasma techniques for which the generated electrons are known to be responsible for reactions. Therefore, it is desirable to explore the interaction of low energy electrons with the co-compounds in the gas phase. The production of chlorine and cyanine anions, initiated by the electron collision with CCl4 and BZN, respectively, undergo nucleophilic substitution SN2 reaction with the precursors molecules for the synthesis of chlorobenzene and tricholoacetonitrile. The mechanism of fragmentation of benzonitrile and the synthesis reactions are rationalized by DFT calculations. The yield of the cyanine anion produced from the ion reaction increases with the temperature of the admixture gas, probed in the 25 °C-100 °C temperature range. The present work may contribute to a potential process for the production of chlorobenzene for instance via (cold) plasma techniques.

Microwave De-Icing Efficiency Improvement of Asphalt Mixture with Structural Layer Optimization and Heat-Resistance Design

The application of microwave de-icing technology in road engineering is constrained by its low energy utilization rate, which can be attributed to low heat production rates and ineffective heat dissipation to the underlying pavement. In this work, asphalt mixtures are designed as an upper layer (heating layer) and a lower layer (thermal-resistance layer). Magnetite slag was selected as a microwave-sensitive source for generating heat, and expanded perlite powder was incorporated into the lower layer as a thermal resistance material. Structural layer optimization and thermal-resistance layer design of the asphalt mixture were carried out by changing the thickness of the upper and lower layers to further improve the heat production rates. The design effectiveness is comprehensively evaluated by factors such as the changing law of the average surface temperature of mixtures, ice-melting time, and cost-effectiveness analyses. The results show that EP possesses better thermal stability, lower microwave energy conversion ability and more excellent heat-resistance potential compared with mineral powder. The heat-resistance layer with EP can prevent heat from being conducted to the lower layer and promote it to concentrate on the specimen surface, which can endow the microwave heating efficiency of specimens to be further improved by up to 26.97% and the de-icing time reduced by 10%, ascribed to the heat-resistance design. Furthermore, the collaborative design of the structural layer optimization and heat-resistance layer can increase energy utilization efficiency and save microwave-absorbing materials while ensuring excellent microwave de-icing efficiency.

Estrogen deficiency reduces maximal running capacity and affects serotonin levels differently in the hippocampus and nucleus accumbens in response to acute exercise.

Estrogen deficiency is associated with unfavorable changes in body composition and metabolic health. While physical activity ameliorates several of the negative effects, loss of ovarian function is associated with decreased physical activity levels. It has been proposed that the changes in brain neurochemical levels and /or impaired skeletal muscle function may underlie this phenomenon. We studied the effect of estrogen deficiency induced via ovariectomy (OVX) in female Wistar rats (n = 64). Rats underwent either sham or OVX surgery and were allocated thereafter into four groups matched for body mass and maximal running capacity: sham/control, sham/max, OVX/control, and OVX/max, of which the max groups had maximal running test before euthanasia to induce acute response to exercise. Metabolism, spontaneous activity, and maximal running capacity were measured before (PRE) and after (POST) the surgeries. Three months following the surgery, rats were euthanized, and blood and tissue samples harvested. Proteins were analyzed from gastrocnemius muscle and retroperitoneal adipose tissue via Western blot. Brain neurochemical markers were measured from nucleus accumbens (NA) and hippocampus (HC) using ultra-high performance liquid chromatography. OVX had lower basal energy expenditure and higher body mass and retroperitoneal adipose tissue mass compared with sham group (p ≤ 0.005). OVX reduced maximal running capacity by 17% (p = 0.005) with no changes in muscle mass or phosphorylated form of regulatory light chain (pRLC) in gastrocnemius muscle. OVX was associated with lower serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) level in the NA compared with sham (p = 0.007). In response to acute exercise, OVX was associated with low serotonin level in the HC and high level in the NA (p ≤ 0.024). Our results highlight that OVX reduces maximal running capacity and affects the response of brain neurochemical levels to acute exercise in a brain region-specific manner. These results may offer mechanistic insight into why OVX reduces willingness to exercise.

Tunable broadband absorbers with ultra-high thermal emissivity for the mxene/ti-based metamaterial

Solar energy was widely used in lots of fields, such as the heat pump technology, seawater desalination, wastewater treatment and photoelectric detection, where efficient use of solar energy was always the goal pursued by mankind. In the work, we proposed a simple and efficient MXene/Ti-based metamaterial absorber and investigated the optical and thermal radiation properties by using the finite-difference time-domain (FDTD) method. The results showed that the average absorption of the MXene/Ti-based metamaterial absorber was higher than 97.6 % from 400 nm to 1600 nm, the maximum absorption reached 99.6 %, and the solar spectrum weighted absorption was close to 98.5 %, and the physical mechanism of the broadband absorption was also explored by theoretical analysis. Compared with the latest reported absorbers, the MXene/Ti-based metamaterial not only had the advantages of low energy loss, high efficiency, and good thermal stability, but also its broadband absorption showed excellent robustness to structural parameters. Moreover, a 75° wide-angle absorption was obtained for the MXene/Ti-based metamaterial, which was independent of polarization. Last but not least, the MXene/Ti-based metamaterial achieved an ultra-high thermal emissivity of 98.3 % at 1600 K, which matched the blackbody radiation curves at 1600 K. These studies had significant implications for catalysis, solar photovoltaics, photovoltaic conversion and other fields.