Total Peak Research Articles

Cortisol secretion in obesity revisited: lower basal serum and salivary cortisol with diminished cortisol response to the low dose ACTH challenge.

Some clinical resemblance may exist between obesity, particularly abdominal obesity, and Cushing's syndrome. This has stimulated ongoing interest in the role of cortisol's secretion pattern, control and metabolism in obesity. To investigate whether basal and stimulated levels of cortisol differ between healthy people with obesity and individuals with normal weight Design: Total, free, and salivary cortisol were tested at baseline state and after 1 g ACTH stimulation in 60 healthy subjects with obesity and 54 healthy lean controls. Baseline total cortisol was lower in subjects with obesity compared to lean controls 347 (265-452(nmol/L vs. [422 (328-493) nmol/L respectively ; p<0.05]. Similarly, basal salivary cortisol was significantly lower in subjects with obesity [7.5 (5.2-9.7) nmol/L vs 10.7 (7.5-17.6) nmol/L; p<0.05]. Upon challenge with ACTH, total peak serum and salivary peak cortisol responses were significantly lower in people with obesity than in lean subjects [665.16±151.8 vs. 728.64±124.2 nmol/L, p<0.05; and 31.66 (19-38.64) vs. 40.05 (31.46-46.64) nmol/L, p<0.05, respectively]. Additionally, baseline total cortisol and salivary cortisol were inversely related to BMI (r=-0.24, r=-0.27; p<0.05 for both) and waist circumference (r=-0.27, r= -0.34; p<0.05 for both). Baseline as well as peak stimulated total serum and salivary cortisol were significantly lower in subjects with obesity. It thus appears that obesity is not associated with enhanced basal or ACTH-stimulated cortisol.

Phytochemical profile and in vitro evaluation of cassava (Manihot esculenta Crantz) foliage as ruminant feed with/without green banana flour

Cassava (Manihot esculenta Crantz) is a crucial crop in tropics and subtropics, primarily cultivated for its tuber. However, its foliage is rich in protein and can supply essential elements for ruminants. The objective of this study was to evaluate the phytochemical compounds by Gas chromatography-MS (GC-MS) and the main phenolic by High Pressure Liquid Chromatography (HPLC) present in cassava foliage, along with the fermentation pattern using a semi-automated gas production (GP) system. The in vitro evaluation was carried out for four diets formulated as follows: T1 (alfalfa: grass hay at ratio of 30: 70); T2 (alfalfa: grass hay: banana flour 30:60:10); T3 and T4 (replaced alfalfa in T1 and T2 with cassava foliage, respectively). The addition of green banana flour aimed to increase the diets’ energy. The GC-MS results indicated that cassava foliage showed a large number of valuable bioactive components, with the biflavonoid isoginkgetin representing the major component at 25.33% of total peak area percentage. The HPLC analysis declared that rutin, gallic acid, and ferulic acid were the main phenolic compounds presented in cassava foliage ethanolic extract. The accumulative gas after 24 h of incubation was significantly lower with cassava diets compared to alfalfa diets, being 119.3 versus 130.1 ml/g DM, respectively. The degradation of both organic matter and neutral detergent fiber was significantly higher with alfalfa compared to cassava diets, while there was no significant difference between alfalfa and cassava diets on final pH, ammonia concentration and protozoal count. Banana flour inclusion, regardless of the forage type, decreased the accumulative gas after 24 h of incubation with about 9% compared with no banana addition. The use of cassava foliage in ruminant diets considered a promising protein source with valuable bioactive components that could have a positive effect on animal health and production.

Facial functionalization carbon fiber with MnO2 nanosheets for high‐performance epoxy composites with excellent flame retardancy and mechanical properties

AbstractThe carbon fiber (CF) reinforced epoxy composites possess exceptional and distinctive properties as advanced composite materials. However, the flammability of epoxy resin and inadequate interfacial bonding between the resin and CF often impose limitations on their broader application. Herein, in order to enhance the flame retardancy of EP composites effectively, a hierarchical reinforcement was developed by facilely growing MnO2 nanosheets onto CF surface through an in situ process. Owing to their synergistic effects of physical barrier and chemical catalytic behavior, the presence of MnO2 nanosheets can effectively retard the combustion process by facilitating charring formation and suppressing heat and smoke release. Specifically, compared to the Untreated CF, the modified fiber reinforced composites exhibited significantly improved fire safety with reduction of 76.23%, 51.5% and 23.1% in peak heat release rate, total heat release and peak smoke production rate, respectively. Additionally, incorporating MnO2 nanosheets significantly enhanced mechanical properties of the composites, leading to remarkable enhancements of 41.8% in flexural strength and 28.14% in interlaminar shear strength. This study proposes an effective strategy for achieving outstanding flame retardancy and mechanical performance, thereby introducing an innovative concept for the production of high‐performance CF reinforced polymer composites.Highlights Growth of MnO2 nanoparticles enhanced the mechanical properties of the CF/EP composites. The CF‐MnO2/EP composites showed excellent flame retardancy. The flame retardant mechanism of CF‐MnO2/EP composites were analyzed. Highlight the potential application of MnO2 in the field of flame retardancy.

Metabolomic Profile Modification in the Cerebellum of Mice Repeatedly Exposed to Khat and Treated with β-Lactamase Inhibitor, Clavulanic Acid.

Catha edulis, commonly known as khat, is used for its psychoactive effects and is considered a natural amphetamine. The current study investigated the metabolomic profile in the cerebellum of mice after repeated exposure to khat and evaluated the effects of clavulanic acid on the metabolomic profile in the cerebellum in khat-treated mice. Male C67BL/6 mice that were 6-9 weeks old were recruited and divided into three groups: the control group was treated with 0.9% normal saline for 17 days; the khat group was given khat extract at a dose of 360 mg/kg via the intraperitoneal (i.p) route for 17 days; and another khat group was treated with khat for 17 days and clavulanic acid at a dose of 5 mg/kg for the last 7 days (days 11-17). At the end of the 17th day, the animals were sacrificed, and their brains were immediately collected and stored at -80 °C. The cerebellum region of the brain was isolated in each group by micropuncture using cryostat and underwent a metabolomics study via Gas Chromatography/Mass Spectroscopy (GC/MS). The total peak area ratios of the selected metabolites in the cerebellum after repeated exposure to the khat extract were significantly reduced (p < 0.05) and treatment of the khat group with clavulanic acid significantly increased (all p < 0.05) the total peak areas ratios of the selected metabolites when compared to their corresponding areas in the alternative khat group. These levels of selected metabolites were further confirmed by observing the metabolite peak area ratios and performing a heat map analysis and a principal compartment analysis of the samples in the cerebellum. A network analysis of altered metabolites in the cerebellum showed a strong correlation between the different metabolites, which showed that an increase in one metabolite can modulate the levels of others. An analysis using the MetaboAnalyst software revealed the involvement of selected altered metabolites like lactic acid in many signaling pathways, like gluconeogenesis, while enrichment analysis data showed altered pathways for pyruvate metabolism and disease pathogenesis. Finally, a network analysis showed that selected metabolites were linked with other metabolites, indicating drug-drug interactions. The present study showed that repeated exposure of mice to khat altered the levels of various metabolites in the cerebellum which are involved in the pathogenesis of different diseases, signaling pathways, and interactions with the pharmacokinetic profile of other therapeutic drugs. The treatment of khat-treated mice with clavulanic acid positively modified the metabolomics profile in the cerebellum and increased the levels of the altered metabolites.

A regression-based parametric model for radiative flux density distribution considering shadowing and blocking effects

In solar power tower system, the Radiative Flux Density Distribution (RFDD) on the receiver surface reflected by a heliostat is influenced by various factors, referred to as scene parameters. The previous analytical models simplify the complex optical modeling process, thus neglecting the comprehensive impacts of the scene parameters, resulting in simulation errors. In this paper, a regression-based parametric model, namely Neural Elliptical Gaussian (NEG), is proposed to address this issue. The NEG model comprehensively considers the impacts of various scene parameters on the RFDD, including heliostat size, slant distance of heliostat, incident angle of sunlight, sunlight distribution parameter, slope error, etc. The relationship between the scene parameters and the RFDD is established using a neural network. Additionally, the overlooked shadowing and blocking effects in the conventional analytical models and data-driven methods are addressed by introducing the flux spot centroid offset in the NEG model. Since the NEG model is established based on statistical regression using a sampled and more accurate flux spot dataset, it shows more accurate flux spot prediction ability. Experimental results show that, for most scenarios, the root mean squared error is less than 0.35%, and the total energy error and peak value error are less than 5%.

High-peak-power short-pulse operation of modulated PCSELs emitting structured light by introducing saturable absorber

Compact, high-peak-power light sources emitting structured light such as multi-dot patterns are desired for face recognition and light detection and ranging (LiDAR) applications, especially in the field of mobile technology. Conventionally, such light sources are composed of VCSEL arrays, lenses, and diffractive optical elements (DOEs), resulting in large and complex systems. To address these issues, we propose and introduce double-lattice structures and saturable absorbers to modulated photonic-crystal surface-emitting lasers (M-PCSELs) capable of emitting arbitrary beam pattens (including structured light) to achieve high-peak-power operation at a low injection current via the Q-switching effect. Considering mobile applications, we experimentally demonstrate short, sub-100-ps pulsed emission of a 28-dot pattern with a total peak power of &gt;5W and narrow divergence angles of &lt;0.5° per dot at an injection of 1A. In addition, by adjusting the carrier lifetime in the saturable absorber, we realize short-pulse operation with a high total peak power of ∼20W at an injection current of 6A.

Fire safety and high mechanical strength epoxy resin enabled by a bis-benzimidazole-primed phenyl phosphonic acid

Preparation of fire safety and high mechanical strength epoxy resin (EP) has become a hot topic for its valuable applications in construction and other fields. Here, bis-2-aminobenzimidazole-modified phenyl phosphonates (PP-BMI) with symmetric structures were synthesized by a simple chemical modification strategy, and its fine structure and composition have been thoroughly characterized. Due to the multifaceted functions of PP-BMI in both gaseous and condensed phases, EP composite with 5 wt% PP-BMI reached a UL-94 V-0 rating and high LOI of 34.3 %. The excellent fire safety of EP/5PP-BMI was further verified with a significant reduction of 57 %, 52 % and 46 % in peak heat release rate (PHRR), total heat release (THR) and peak CO production (P-COP), respectively, compared to the original EP. The flame retardancy of PP-BMI on EP can be attributed to the dilution of non-combustion gases, free radical trapping and catalytic charring functions. More importantly, PP-BMI can further enhance the mechanical properties of EP, which is closely related to the interaction between PP-BMI and EP matrix. Furthermore, EP/PP-BMI composites have good resistance to acids and alkalis, ensuring long-lasting flame retardancy and mechanical properties. This work provides a new strategy for realizing epoxy composites with high fire safety and excellent mechanical properties in construction and multifaceted areas.

Melamine-based biomass-containing P/N synergistic flame retardants confer superb flame retardancy and toughness to epoxy resins

Epoxy resin (EPs) coatings for aircraft need to have good flame retardant properties and toughness. On the other hand, to meet the needs of sustainable development, EPs also have high environmental friendliness and low cost requirements. In light of this, a one-pot approach was used to create a bio-based phosphorus‑nitrogen synergistic flame retardant (MDV) employing DOPO, vanillin, and MA as raw materials. The results showed that MDV can give EP superb flame retardancy and toughness. With the addition of 3 wt% MDV, the tensile and flexural strengths of EP composites increased by 13.6 % and 14.5 %, respectively, and the impact strength increased from 13.9 KJ/m2 to 43.1 KJ/m2. The excellent toughness enhancement comes from the fact that the structure of MDV itself can preferentially consume and dissipate energy when counteracting external impacts. In addition, MDV/EP also has excellent flame retardant properties, showing good self-extinguishing capability off fire in tests. Compared with pure EP, the total heat release (THR) and peak heat release rate (PHRR) of 7-MDV/EP composites were reduced by 45.3 % and 64.5 %, respectively. Mechanistic analyzes showed that the segregation of the condensed phase and the gas-phase flame-retardant effect both originated from the P/N synergistic effect, which was the source of the excellent flame-retardant effect of MDV/EP.

Decentralized coordination of distributed energy resources through local energy markets and deep reinforcement learning

As the energy landscape evolves towards sustainability, the accelerating integration of distributed energy resources poses challenges to the operability and reliability of the electricity grid. One significant aspect of this issue is the notable increase in net load variability at the grid edge.Transactive energy, implemented through local energy markets, has recently garnered attention as a promising solution to address the grid challenges in the form of decentralized, indirect demand response on a community level. Model-free control approaches, such as deep reinforcement learning (DRL), show promise for the decentralized automation of participation within this context. Existing studies at the intersection of transactive energy and model-free control primarily focus on socioeconomic and self-consumption metrics, overlooking the crucial goal of reducing community-level net load variability.This study addresses this gap by training a set of deep reinforcement learning agents to automate end-user participation in an economy-driven, autonomous local energy market (ALEX). In this setting, agents do not share information and only prioritize individual bill optimization. The study unveils a clear correlation between bill reduction and reduced net load variability. The impact on net load variability is assessed over various time horizons using metrics such as ramping rate, daily and monthly load factor, as well as daily average and total peak export and import on an open-source dataset.To examine the performance of the proposed DRL method, its agents are benchmarked against a near-optimal dynamic programming method, using a no-control scenario as the baseline. The dynamic programming benchmark reduces average daily import, export, and peak demand by 22.05%, 83.92%, and 24.09%, respectively. The RL agents demonstrate comparable or superior performance, with improvements of 21.93%, 84.46%, and 27.02% on these metrics. This demonstrates that DRL can be effectively employed for such tasks, as they are inherently scalable with near-optimal performance in decentralized grid management.

Excellent flame retardant and tough epoxy thermosets with imidazolium tributyl phosphate ionic liquid

The brittleness and flammability of epoxy thermosets (EP) have largely limited their applications. In this work a phosphorus-containing ionic liquid 1-methylimidazolium tributyl phosphate ([Mim]TBP) is designed and synthesized to develop high-performance and flame-retardant epoxy thermosets. [Mim]TBP significantly accelerates the curing and improves the toughness of epoxy thermosets. The tensile toughness, tensile strength, impact strength and flexural strength of samples with 10phr [Mim]TBP increase by 419.7 %, 100.2 %, 71.7 % and 58.3 %, compared with pure EP, respectively. The increased toughness is due to the significant energy dissipation caused by the ionic bonds breaking between Mim and TBP. When the [Mim]TBP content exceeds 10 phr, the limiting oxygen index (LOI) can reach over 30 % and UL-94 test pass the V-0 rating. The peak heat release rate (pHRR), total heat release (THR), total smoke release (TSR) and peak CO production (PCOP) values effectively decrease by 31.5 %, 30.6 %, 48.3 % and 6.3 %, respectively, thanks to the gas and condensed phase mechanisms of the [Mim]TBP. A new strategy was provided for the development of toughness and fire safety performance epoxy thermosets for high-performance industrial applications.

Estrous activity in nulliparous heifers with divergent genetic merit for fertility traits

This observational study determined the effect of genetic merit for fertility traits on estrous activity and duration and inter-estrous interval in nulliparous dairy heifers. We also compared estrous activity between estrous events with or without conception and determined the effect of genetic merit for fertility traits on age and body weight at time of first detected estrous activity event. Activity monitoring devices (Heatime, SCR Engineers) were fitted to 7-9-mo aged Holstein-Friesian heifers with positive or negative genetic merit for fertility traits (POS FertBV: average +5%, n = 275; NEG FertBV: average -5%, n = 249) and activity data was collected to the end of the first breeding period (15-17-mo). An estrous event was defined as when the activity change index exceeded 19.2 activity units (AU) for ≥6 consecutive h. In total, 2,434 estrous events were identified (POS FertBV: n = 1454; NEG FertBV: n = 980). Estrous event duration was defined as the period when the threshold was first exceeded and when activity dropped below threshold, without another event starting within 24 h of the end of the previous event. This definition included occurrences where activity crossed the threshold multiple times in a day; these were classified as a single estrous event. A second measure, high activity duration, was defined as the total time activity exceeded the threshold. To characterize estrous activity, baseline activity was determined from the previous 7 d of activity. Peak activity and total activity (area under the curve of activity above baseline) were calculated. A fifth variable, inter-estrous interval, was calculated as a proxy for estrous cycle length. Total activity and peak activity were greater in POS than NEG FertBV heifers (total activity: 548 vs 464 AU, SED = 19.6 AU; peak activity: 72 vs 65 AU, standard error of the difference (SED) = 1.5 AU). The POS FertBV group had a mean estrous event duration and high activity duration of 15.1 h and 15.0 h, compared with 14.1 and 14.1 h for the NEG FertBV group (SED = 0.30 and 0.29 h, respectively). Inter-estrous interval did not differ between POS and NEG FertBV heifers (19.5 vs 20.0 d, SED = 0.49). Estrous events associated with conception were shorter than those not associated with conception (mean ± standard error of the mean, high activity duration: 13.0 ± 0.25 h vs 13.9 ± 0.31 h, estrous event duration: 13.1 ± 0.25 h vs 14 ± 0.32 h) and had less total activity (408 ± 15.2 vs 487 ± 18.2 AU). The POS FertBV heifers were more likely to have their first estrous activity event than NEG FertBV heifers by a given age (HR = 1.26, 95% CI = 1.0 to 1.6) or body weight (HR = 1.35, 95% CI = 1.1 to 1.6). The outcomes of this study provide evidence that positive genetic merit for fertility traits is associated with more overt estrous expression. Therefore, estrous expression traits may have potential to be used as earlier-in-life predictors of genetic merit for fertility.

Image of the Kerr–Newman Black Hole Surrounded by a Thin Accretion Disk

The image of a Kerr–Newman (KN) black hole (BH) surrounded by a thin accretion disk is derived. By employing elliptic integrals and ray-tracing methods, we analyze photon trajectories around the KN BH. At low observation inclination angles, the secondary image of particles is embedded within the primary image. However, as the inclination increases, the primary and secondary images separate, forming a hat-like structure. The spin and charge of the BH, along with the observer’s inclination angle, affect the image’s asymmetry and the distortion of the inner shadow. To investigate the redshift distribution on the accretion disk, we extended the inner boundary of the accretion disk to the event horizon. The results show that the redshift distribution is significantly influenced by the observation inclination angle. Furthermore, we conducted a detailed analysis of the KN BH image using fisheye camera ray-tracing techniques and found that the optical appearance and intensity distribution of the BH vary at different observation frequencies (specifically at 230 GHz and 86 GHz). We also examined differences in intensity distribution for prograde and retrograde accretion disk scenarios. Comparing observational at the two frequencies, we found that both the total intensity and peak intensity at 86 GHz are higher than those at 230 GHz.

Application of the Agilent 2100 Bioanalyzer instrument as quality control for next-generation sequencing.

Next-generation sequencing (NGS) technologies have expanded the spectrum of forensic DNA analysis by facilitating efficient and precise genotyping of a large number of genetic markers. Yet, challenges persist regarding complex sample processing and assurance of equal molar concentrations across pooled samples. Since optimal cluster density is crucial for sequencing performance, the determination of both quantity and quality is indispensable for library preparation. In this study, we investigated the application of the Agilent 2100 Bioanalyzer for library quality control, as studies for forensic approaches, particularly for highly degraded postmortem samples, are rare. Our analysis encompassed assessing total DNA concentrations, fluorescence unit (FU) values, and adapter dimer concentrations in purified DNA libraries derived from buccal swabs and tissue samples of decomposed corpses. The sensitivity study tested a serial dilution derived from buccal swabs and revealed a decrease in FU values and an increase in adapter dimers with declining DNA input concentrations. Deviations in total DNA concentrations and average peak heights between the Agilent 2100 Bioanalyzer runs indicated a lack of repeatability in data and presented challenges in accurate quantification, which was also observed in previous studies. Yet, the analysis of degraded samples from decomposed human remains has shown the ability to detect adapter dimer concentrations, which can be crucial for the quality of subsequent NGS library preparation and sequencing success. Therefore, the Agilent 2100 Bioanalyzer proves to be a valuable tool for NGS quality control.

The Influence of Temperature Disturbance on Space Inertial Sensors.

The TianQin program is an independently proposed space-borne detection initiative from China. The inertial sensor, as a crucial component, is susceptible to disturbances from temperature fluctuations, the impact of which on acceleration measurements remains elusive. Therefore, a comprehensive analysis on the influence of temperature disturbance is necessary to avoid errors in acceleration measurement. In this study, we proposed a complete scheme for calculating the level of acceleration noise. Based on the traditional temperature control scheme of using a heat pipe, we developed a systematic heat transfer simulation model to obtain the temperature signals. These signals can then be converted into the frequency domain and used to calculate the acceleration noise level within the target bandwidth. Our results indicate that, with a temperature control of 0.13 K/Hz1/2@1 mHz, the largest contributions to acceleration noise come from the outgassing effect, radiometer effect, and radiative pressure effect, in descending order. The total noise peak is 3.6×10-12 m/(s2⋅Hz1/2) at 1 mHz, which is more than three orders of magnitude higher than the TianQin target of 10-15 m/(s2⋅Hz1/2). This study provides new avenues for evaluating measurement errors and solutions for the TianQin program.

Chemical composition, antioxidant, and enzyme inhibition activities of Crithmum maritimum essential oils: the first chemo-biological study for species grown in North Africa

Crithmum maritimum (sea fennel), is a halophytic plant species found globally in coastal environments. This study is the first investigation into the chemical composition and biological activities of C. maritimum growing wildly in Jebel Akhdar, Libya. Gas Chromatography-Mass Spectrometry (GC-MS) analysis was utilized to identify and profile the plant’s volatile components; it resulted in the identification of twenty-four components, representing 99.17% of the total peaks in the GC-MS chromatogram. The analysis revealed that thymyl methyl ether, γ-terpinene, and ledene oxide, were the major volatile constituents of the plant at relative percentage levels of 56.86, 16.17, and 4.32%, respectively. The analysis also indicated substantial variations in the volatile composition of C. maritimum Libyan species compared to those from various geographic regions. The plant’s volatile oil quality was evaluated by investigating its in vitro antioxidant activity and the oil’s ability to inhibit acetylcholinesterase (AChE) and tyrosinase enzymes. The oil markedly scavenged the free radicals and reduced the ferric ions in the DPPH and FRAP assays at levels of 34.30 ± 0.10 and 38.90 ± 0.51 Trolox equivalents, respectively. The plant’s volatile oil has substantially reduced the AChE at the IC50 value of 34.43 ± 0.25 compared to its effect against tyrosinase (IC50 12.449 ± 0.68). The in silico approach was used to highlight the mechanisms underlying the enzyme inhibitory effect of the plant volatile oil. The stigmastene and γ-santonin demonstrate stronger binding affinity towards AChE and tyrosinase compared to the co-crystalized controls, donepezil and tropolone. The study provides significant information for the environmental changes effect on the volatile constituents of C. maritimum and highlights the plant’s importance within the scope of its antioxidant and enzyme inhibition activities.

Streptomyces fradiae Mitigates the Impact of Potato Virus Y by Inducing Systemic Resistance in Two Egyptian Potato (Solanum tuberosum L.) Cultivars

In this study, the impact of culture media filtrate of QD3 actinobacterial isolate on two potato cultivars, Spunta and Diamond, infected with potato virus Y (PVY) was investigated. Various parameters, including infection percentage, PVY virus infectivity, disease severity scoring, PVY optical density, photosynthetic and defense-related biochemical markers, enzymatic profiling, phenolic compounds, proline content, salicylic acid levels, and growth and yield parameters, were assessed to elucidate the potential of the QD3 actinobacterial isolate culture filtrate in mitigating PVY-induced damage. The physiological and biochemical characteristics of the QD3 actinobacterial isolate, including its salinity tolerance, pH preferences, and metabolic traits, were investigated. Molecular identification via 16S rRNA gene sequencing confirmed its classification as Streptomyces fradiae QD3, and it was deposited in GenBank with the gene accession number MN160630. Distinct responses between Spunta and Diamond cultivars, with Spunta displaying greater resistance to PVY infection. Notably, pre-infection foliar application of the QD3 filtrate significantly reduced disease symptoms and virus infection in both cultivars. For post-PVY infection, the QD3 filtrate effectively mitigated disease severity and the PVY optical density. Furthermore, the QD3 filtrate positively influenced photosynthetic pigments, enzymatic antioxidant activities, and key biochemical components associated with plant defense mechanisms. Gas chromatography‒mass spectrometry (GC‒MS) analysis revealed palmitic acid (hexadecanoic acid, methyl ester) and oleic acid (9-octadecanoic acid, methyl ester) as the most prominent compounds, with retention times of 23.23 min and 26.41 min, representing 53.27% and 23.25%, respectively, of the total peak area as primary unsaturated fatty acids and demonstrating antiviral effects against plant viruses. Cytotoxicity assays on normal human skin fibroblasts (HSFs) revealed the safety of QD3 metabolites, with low discernible toxicity at high concentrations, reinforcing their potential as safe and effective interventions. The phytotoxicity results indicate that all the seeds presented high germination rates of approximately 95–98%, suggesting that the treatment conditions had no phytotoxic effect on the Brassica oleracea (broccoli) seeds, Lactuca sativa (lettuce) seeds, and Eruca sativa (arugula or rocket) seeds. Overall, the results of this study suggest that the S. fradiae filtrate has promising anti-PVY properties, influencing various physiological, biochemical, and molecular aspects in potato cultivars. These findings provide valuable insights into potential strategies for managing PVY infections in potato crops, emphasizing the importance of Streptomyces-derived interventions in enhancing plant health and crop protection.

Dynamics and energy harvesting of a flow-induced snapping sheet with nonuniform stiffness distribution

Energy harvesting through periodic snap-through of a buckled sheet has recently gained considerable attention because of its potential applications in energy harvesting in low incoming flow. Although the snapping dynamics of uniform buckled sheets has been extensively studied, the present work focuses on the energy harvesting and dynamics of a nonuniform snapping sheet with both of its ends clamped in a channel flow. The analysis reveals that the sheet undergoes periodic snap-through oscillations, with its rear half consistently serving as the main contributor to effective energy harvesting, and the potential energy contributing significantly more than the kinetic energy. Varying the stiffness difference ΔEI* shows that increasing the stiffness of the rear part and decreasing that of the fore part shifts the deformation wave toward upstream and enhances the snapping amplitude of the fore part, optimizing energy extraction. At a length compression ratio ΔL* = 0.3, the maximum potential energy is observed for ΔEI* = 1, and the total energy peaks at ΔEI* = 2. The study also identifies an optimal ΔL* = 0.4 that maximizes both total and potential energies, and triples the potential energy in comparison with ΔL* = 0.1. However, the enhancement of nonuniformity disappears at ΔL* &amp;gt; 0.3 for the total energy and ΔL* &amp;gt; 0.2 for the potential energy. These findings provide insights to aid optimization of the design and performance of snapping sheet energy harvesters.

Impact of methane and other precursor emission reductions on surface ozone in Europe: scenario analysis using the European Monitoring and Evaluation Programme (EMEP) Meteorological Synthesizing Centre – West (MSC-W) model

Abstract. The impacts of future methane (CH4) and other precursor emission changes are investigated for surface ozone (O3) in the United Nations Economic Commission for Europe (UNECE) region excluding North America and Israel (the EMEP region, for European Monitoring and Evaluation Programme) for the year 2050. The analysis includes a current legislation (CLE) and maximum feasible technical reduction (MFR) scenario, as well as a scenario that combines MFRs with an additional dietary shift that also meets the Paris Agreement objectives with respect to greenhouse gas emissions (LOW). For each scenario, background CH4 concentrations are calculated using a probabilistic Earth system model emulator and combined with other precursor emissions in a three-dimensional Eulerian chemistry-transport model. While focus is placed on peak season maximum daily 8 h average (MDA8) O3 concentrations, a range of other indicators for health and vegetation impacts are also discussed. Our analysis shows that roughly one-third of the total peak season MDA8 reduction achieved between the 2050 CLE and MFR scenarios is attributable to CH4 reductions, resulting predominantly from CH4 emission reductions outside of the EMEP region. The impact of other precursor emission reductions is split nearly evenly between the reductions inside and outside of the EMEP region. However, the relative importance of CH4 and other precursor emission reductions is shown to depend on the choice of O3 indicator, though indicators sensitive to peak O3 show generally consistent results. The analysis also highlights the synergistic impacts of CH4 mitigation as reducing solely CH4 achieves, beyond air quality improvement, nearly two-thirds of the total global warming reduction calculated for the LOW scenario compared to the CLE case.

Towards socially equitable public transport systems: The effect of COVID-19 on taxi trip behavior

The COVID-19 pandemic emerged as a very influential occurrence with a profound impact on a global scale. The onset of the pandemic abruptly disrupted the regular course of everyday activities, primarily impacting urban regions. Hence, it is imperative to understand the effects of the COVID-19 pandemic on modern urban areas. This study seeks to analyze the effect of the pandemic on travel behavior by utilizing GPS data obtained from taxis, with a specific focus on spatial socioeconomic features. The M2 metro line in Istanbul has been selected for evaluation. In this analysis, four distinct periods are considered: total, off-peak, morning, and evening peaks. The stations are categorized using K-means clustering. The estimation models are constructed using ordinary least squares (OLS), spatial autoregression (SAR), and geographically weighted regression (GWR) techniques, which are applied to the variation in daily average cab trips and the characteristics of stations. The GWR models provide superior performance in comparison to the other two models, with notable distinctions observed in peak times, particularly morning peak when compared to total and off-peak counts. The findings indicate that factors such as population, population density, socioeconomic status, and the quantity of shopping malls are influential variables in elucidating and forecasting the fluctuations in taxi trip counts.

An in situ combustion carbon deposit diagnostic instrument based on Raman microscopy.

Carbon deposit of the aero-engine combustor, resulting from incomplete combustion and fuel pyrolysis, can cause nozzle blockage, fuel consumption increase, power decrease, and even flight unsafety. In this work, an in situ combustion carbon deposit diagnostic instrument is developed to reveal the crystalline structure and the changes under real combustion conditions. The instrument integrates the in situ microscopic Raman technique and the combustion system. The burner is characterized by a sloping tip, making it possible to observe the coke from the side view. The burner is installed to the optical positioning stage by a specially made adapter so that the relative location is fixed and it is possible to observe the carbon deposit from the ignition. The carbon deposit of acetylene/air diffusion jet flame was studied. A 50× objective lens was used to collect the Raman scattering signal of carbon deposits continuously 30s after ignition. A five-band model was used to fit the Raman spectra. The time-resolved information was calculated, including the normalized total area, area proportion, peak ratio, and crystalline size. The results show that the carbon deposit of acetylene flames with different velocities presents different tendencies of formation and degree of graphitization, which is attributed to the influence of temperature and flow. The performance of this system is evaluated quantitatively. The signal-to-noise ratio of Raman spectra of carbon deposits ranges from 6.4 to 28.9. This work provides an in situ method to analyze the dynamic change of carbon deposit on the burner, and further work is needed to reveal the mechanism.