Incremental Rate Research Articles

P2P credit auction vs. net metering: Benefit analysis for prosumers under incremental block rate electricity tariff

In order to increase the economic benefits of residential photovoltaic (PV), many countries have considered diverse compensation policies for surplus energy, such as fixed feed-in tariff, time-varying feed-in tariff, and net metering, where the surplus energy is offset against consumption. More recently, there has been a growing interest in schemes that allow end-users to trade surplus energy via peer-to-peer (P2P) electricity trading, rather than relying on government incentives. This study conducts a quantitative analysis of on how the introduction of P2P trading affects the benefits of each stakeholder, offering a guide for policy adoption. Firstly, this study devises a P2P trading mechanism based on credit auctions tailored for residential, while considering the application of the increasing block rate tariff often applied to residential customers in the real world, and assesses its benefits in comparison to the current net metering scheme. Multiple case studies were undertaken, encompassing various scenarios, including the level of purchase price of utility for uncleared auction offers, the proportion of prosumers participating in the trading network, and the level of capacity of PV. This study shows that the P2P trading does not always yield positive benefits for prosumers compared to the prior policy. Nevertheless, this study identifies specific conditions under which the P2P trading can stimulate residential PV installations.

Improving new energy subsidy efficiency considering learning effect: A case study on wind power

Subsidy policies are instrumental in driving the development of new energy. However, the effective allocation of new energy subsidies over time is challenging given fiscal constraints. This study addresses this challenge by considering the learning effect associated with the new energy industry. A two-stage dynamic programming model is proposed to capture the investment decision-making process of companies under new energy subsidy policies and government subsidy setups. Theoretical findings suggest that company investment decisions in new energy are influenced by a guiding principle: The subsidy rate should be negatively correlated with the variation rate of production scale increment (VRPSI). We calibrate this investment decision principle using wind power data from 14 countries. According to this principle, excessive subsidy rates may result in a low VRPSI, thereby diminishing future investment profitability in the new energy industry and leading to subsidy inefficiency. Upon investigating the efficiency of annual subsidy allocation, we find that the subsidy rates were potentially set too high in 2014, 2016, and 2017. Furthermore, the government should exercise caution regarding an inefficient subsidy pattern whereby companies invest in new energy only when the subsidy rate exceeds a certain threshold, neglecting traditional power sources. It is crucial to note that although this study uses wind power industry data for calibration and simulation, the theoretical model can be broadly applied to other new energy industries and emerging industries with increasing marginal net profit.

Vortex–airfoil interaction noise control using virtual serrations and surface morphing generated by leading-edge blowing

Suppression of vortex–airfoil interaction noise from a rod-airfoil model by virtual serrations and surface morphing formed by the leading-edge (LE) blowing was investigated experimentally in an anechoic wind tunnel. The control efficiency of the virtual serrations and surface morphing was evaluated and analyzed by setting different air flow rates (Q), deflection angles (α), and orifice number (M). Noise measurements by far-field microphones show that both can effectively reduce the peak tonal noise generated by the vortex–airfoil interaction, with the control efficiency increasing with the increment of flow rate Q. As for the LE serration, the noise reduction increases with the virtual serration amplitude ratio Av (=Ub/U∞, Ub: blowing velocity; U∞: wind speed), but decreases slightly with the deflection angle α. A reduction of 12–14 dB is obtained when Av = 3.7 and α = 0° or 10°, and there exists a critical amplitude of Av = 1.5, under which no noise reduction is achieved. Compared to the serration at the same flow condition, the virtual surface morphing has much lower control efficiency, with a maximum noise reduction of 3–5 dB. The flow visualization by the particle image velocimetry technique reveals that both build buffer zones in the front of the airfoil LE, preventing the vortices from directly impinging upon the solid LE, thus reducing the intensity of vortex–airfoil interaction. In particular, the virtual serration breaks up the large-scale vortex structure into small-scale vortices, manifesting its high noise control efficiency.

Addition of Contrast-enhanced Mammography to Tomosynthesis for Breast Cancer Detection in Women with a Personal History of Breast Cancer: Prospective TOCEM Trial Interim Analysis.

Background Digital breast tomosynthesis (DBT) is often inadequate for screening women with a personal history of breast cancer (PHBC). The ongoing prospective Tomosynthesis or Contrast-Enhanced Mammography, or TOCEM, trial includes three annual screenings with both DBT and contrast-enhanced mammography (CEM). Purpose To perform interim assessment of cancer yield, stage, and recall rate when CEM is added to DBT in women with PHBC. Materials and Methods From October 2019 to December 2022, two radiologists interpreted both examinations: Observer 1 reviewed DBT first and then CEM, and observer 2 reviewed CEM first and then DBT. Effects of adding CEM to DBT on incremental cancer detection rate (ICDR), cancer type and node status, recall rate, and other performance characteristics of the primary radiologist decisions were assessed. Results Among the participants (mean age at entry, 63.6 years ± 9.6 [SD]), 1273, 819, and 227 women with PHBC completed year 1, 2, and 3 screening, respectively. For observer 1, year 1 cancer yield was 20 of 1273 (15.7 per 1000 screenings) for DBT and 29 of 1273 (22.8 per 1000 screenings; ICDR, 7.1 per 1000 screenings [95% CI: 3.2, 13.4]) for DBT plus CEM (P < .001). Year 2 plus 3 cancer yield was four of 1046 (3.8 per 1000 screenings) for DBT and eight of 1046 (7.6 per 1000 screenings; ICDR, 3.8 per 1000 screenings [95% CI: 1.0, 7.6]) for DBT plus CEM (P = .001). Year 1 recall rate for observer 1 was 103 of 1273 (8.1%) for (incidence) DBT alone and 187 of 1273 (14.7%) for DBT plus CEM (difference = 84 of 1273, 6.6% [95% CI: 5.3, 8.1]; P < .001). Year 2 plus 3 recall rate was 40 of 1046 (3.8%) for DBT and 92 of 1046 (8.8%) for DBT plus CEM (difference = 52 of 1046, 5.0% [95% CI: 3.7, 6.3]; P < .001). In 18 breasts with cancer detected only at CEM after integration of both observers, 13 (72%) cancers were invasive (median tumor size, 0.6 cm) and eight of nine (88%) with staging were N0. Among 1883 screenings with adequate reference standard, there were three interval cancers (one at the scar, two in axillae). Conclusion CEM added to DBT increased early breast cancer detection each year in women with PHBC, with an accompanying approximately 5.0%-6.6% recall rate increase. Clinical trial registration no. NCT04085510 © RSNA, 2024 Supplemental material is available for this article.

Sexual dimorphism of the increment rate of age-specific incidence of actinic keratoses: an observational, single-centre study.

Sexual dimorphism of the increment rate of age-specific incidence of actinic keratoses: an observational, single-centre study.

Immobilization of radioactive sulphate waste simulate in polymer–cement composite based on recycled expanded polystyrene foam: evaluation of the final waste form resistance for Cs-134 and Co-60 leachability

The present study investigates to incorporate spiked sulfate solution simulate into polymer–cement composite (PCC) based on recycled expanded polystyrene foam. The main aim is to convert the waste stream into leach resistance solid forms able to slow down or even to retard the back release of hazardous radionuclides to the surrounding. Effective parameters e.g. leachant medium, temperature, radioactivity contents, leachant volumes and radionuclides speciation versus the leaching time were studied. The incremental leach rate (Rn, cm/day) and the leach index (Lx) were evaluated for the final waste form after 145 days. The experimental results revealed that the Lx for the all variances can fulfil the waste acceptance criteria for the disposal facility and are above the threshold value of 6. Moreover, leach rate percentages for Cs-134 and Co-60 were not exceeding 2%. The acquired data, based on lab leaching experiments, can recommend the developed PCC under consideration for solidification of radioactive sulphate waste stream safely.

Dynamic Modeling of Environmental Subsidies

In this research, the intertemporal optimal management of subsidies offered by the environmental regulator and the dynamic conflict between two groups of economic agents involved in environmental quality are discussed. First the environmental model is examined in its optimal control management form with two state variables. The analysis of the improved model, inspecting the social planner’s decision (policy) variable, the variable which influences not only environmental quality but the national budget stock, reveals that is dependent on the growth of the national budget stock. A negative growth rate leads to the long run saddle point equilibrium, while an incremental growth rate, but less than the model’s discount rate, leads to an interesting complicated limit cycle equilibrium, for which under certain parameter values the orbit’s phase portrait can be drawn. For the dynamic game model between the social planner and natural resource exploiters, the equilibrium conditions are examined. It is rather a richer than the point equilibrium for which the cyclical strategies have great importance. Therefore, the conditions for that rich equilibrium are found. As a continuation, the paper concludes that the equilibrium condition is that the players’ discount rates are both greater than the national budget interest rate. Finally, the certain values of the equilibrium strategies and national budget stock are provided.

Revisiting investment and its determinants through threshold analysis

AbstractSince the time of classical economists, investment decisions hold centre stage in economic theory. In this article, we integrate classical economists' perspectives on the determinants of investment with the Keynesian theory of effective demand. For this purpose, we employ variables to capture the effects of profitability, the state of demand, and the financial and risk conditions using time series data from 17 major OECD economies spanning the 1960–2017 period. Two are the salient features of our article: The first is the use as profitability variables, the marginal efficiency of capital or the incremental rate of return, and the second is the use of regime changes and respective threshold values for these two key variables. The econometric results show that the profitability variables are decisive in shaping investment decisions and designating phase changes.

In-vitro Analysis of Antioxidant, Anti-inflammatory, Antidiabetic and Antimicrobial Studies of Kaempferol Ethosomes

Flavonoids have potent antioxidant, anti-inflammatory, antidiabetic and antimicrobial properties, and they generally report to have poor bioavailability and dissolution. This work emphasized on developing and characterizing kaempferol-loaded ethosomes and evaluating them for in-vitro assessments. The cold method was used for preparing kaempferol (KMP) ethosomes by means of soya lecithin, ethanol, and propylene glycol. The ethosomes were evaluated for vesicle size (253 ± 2.6), entrapment efficiency (91.05 ± 0.11%), zeta potential (-31.7 ± 1.12 mV), and drug release (89.91 ± 3.3%), compared with the release of pure drug (kaempferol), which was 48.96 ± 3.6% and showed an approximate double increment in the release rate. KMP ethosomes follow the Korsmeyer-Peppas model. The kaempferol ethosomes were further examined for their various in-vitro pharmacological activities as antimicrobial, anti-inflammatory, antidiabetic, and antioxidant in comparison with pure kaempferol. The results reported kaempferol loaded-ethosomes showed a strong anti-inflammatory, antimicrobial, antioxidant, and antidiabetic properties and thus, can be exploited as a viable drug delivery for various therapeutic applications.

Incidence of oncogenic HPV infection in women with and without mental illness: A population-based cohort study in Sweden.

Women with mental illness experience an increased risk of cervical cancer. The excess risk is partly due to low participation in cervical screening; however, it remains unknown whether it is also attributable to an increased risk of infection with human papillomavirus (HPV). We aimed to examine whether women with mental illness had an increased infection rate of HPV compared to women without mental illness. Using a cohort design, we analyzed all 337,116 women aged 30 to 64 and living in Stockholm, who had a negative test result of 14 high-risk HPV subtypes in HPV-based screening, during August 2014 to December 2019. We defined women as exposed to mental illness if they had a specialist diagnosis of mental disorder or had a filled prescription of psychotropic medication. We identified incident infection of any high-risk HPV during follow-up and fitted multivariable Cox models to estimate hazard ratios (HR) with 95% confidence intervals (CI) for HPV infection. A total of 3,263 women were tested positive for high-risk HPV during follow-up (median: 2.21 years; range: 0 to 5.42 years). The absolute infection rate of HPV was higher among women with a specialist diagnosis of mental disorder (HR = 1.45; 95% CI [1.34, 1.57]; p < 0.001) or a filled prescription of psychotropic medication (HR = 1.67; 95% CI [1.55, 1.79]; p < 0.001), compared to women without such. The increment in absolute infection rate was noted for depression, anxiety, stress-related disorder, substance-related disorder, and ADHD, and for use of antidepressants, anxiolytics, sedatives, and hypnotics, and was consistent across age groups. The main limitations included selection of the female population in Stockholm as they must have at least 1 negative test result of HPV, and relatively short follow-up as HPV-based screening was only introduced in 2014 in Stockholm. Mental illness is associated with an increased infection rate of high-risk HPV in women. Our findings motivate refined approaches to facilitate the WHO elimination agenda of cervical cancer among these marginalized women worldwide.

Tailoring the surface features of CaWO4 by coupling with tubular g-C3N4 for enhanced solar photocatalysis and thermal energy storage

Rising energy and environmental crisis has led researchers to develop novel bifunctional materials. Herein, we report the construction of bifunctional hybrid materials for thermal energy storage and solar photocatalytic systems. Such a novel type of green material including calcium tungstate (CaWO4) and tubular graphitic carbon nitride (g-C3N4) was successfully fabricated via thermal mixing method. X-ray diffraction analysis confirmed the formation of both CaWO4 and g-C3N4 in the composite while morphological analyses verified the successful attachment of CaWO4 particles over the tubular g-C3N4 structure. The wide band gap energy (3.6 eV) of the pristine CaWO4 significantly decreased to 1.85 eV after coupling with g-C3N4. The hybrid catalyst showed superior photocatalytic degradation of Allura red (79.3 % within 120 min) and the rate constant was found 31.3-folds higher compared to pristine CaWO4 (13.3 % removal), which was ascribed to strong light harvesting, increased surface area, smaller crystallite size and fast electron transfer rate. In addition to catalytic functionality, the synthesized pristine and hybrid catalysts were also used in the preparation of lauric acid-based phase change materials (PCMs) and thermal properties of different fillers were examined. The 1 wt% CaWO4/g-C3N4 filler loaded composite displayed 13.03 % increment in heat storage rate (oC/s) when compared with lauric acid, demonstrating the essential role of the hybrid material over the PCM structure. The as-prepared hybrid materials displayed a bifunctional activity derived from incorporation of carbon nitride and thus verified a great potential for different applications due to their enhanced features.

Influence of stress history on thermal conductivity of saturated fine-grained soils

This research investigated variations in thermal conductivity k for normally consolidated (NC) and overconsolidated (OC) saturated fine-grained soils at different levels of vertical effective stress. A series of undrained heating tests were performed using a specially designed consolidometer with central radial heating arrangement and temperature measurements within a soil specimen. For different soils investigated in this research, k correlated well with soil consolidation characteristics (compression index λ and swelling index κ) and vertical effective stress σvʹ at both NC and OC states. However, the rates of increment of steady- and transient-state values of k ( kst and ktr, respectively) with σv′ differed from one soil to another. For OC clays, both ktr and kst increased with preconsolidation stress σc′. A set of equations were proposed to estimate both kst and ktr for saturated fine-grained soils as functions of σv′, λ, κ, and stress history. At a particular value of σvʹ, the dependence of k on overconsolidation ratio (OCR) and σc′ marked the importance of considering stress history in the determination of k. The influence of soil mineral composition on k was also explored. Quantification of soil mineralogical composition and available data on mineral thermal conductivity enabled prediction of ktr with reasonable accuracy.

Effect of the electrostatic field on fish deterioration: the case of the European anchovy (Engraulis encrasicolus)

SummaryThe European anchovy (Engraulis encrasicolus) being a species very rich in long‐chain fatty acids, it is subject to rapid spoilage with consequent sensory losses. Therefore, this study aimed to verify the effect of a low‐voltage electrostatic field (DENBA+) on the quality of fresh anchovies in a refrigerated environment. During 9 days of storage, anchovy samples were analysed from a chemical (TVB‐N and TBARS), physical (texture analysis), microbiological (microbial count) and sensory (QIM) point of view and compared to control samples (without the electrostatic field). DENBA+ technology was able to reduce of 20% the QI score increment rate with respect to the control sample justified by a better quality of the samples after 7 days of storage. In addition, loads of spoiling microbes were significantly lower in DENBA+ after 9 days of storage. This non‐thermal technology has shown positive effects for long periods of storage.

Thermal performance of a stack cooling radiator coupled with spray cooling for the future fuel cell electric vehicles

Proton-exchange membrane fuel-cell electric vehicles require an appropriate stack cooling radiator (SCR) system to achieve optimal performance and safe operation. However, SCR cannot achieve high heat rejection under high power demands and hot ambient conditions. Hence, either the SCR needs to be enlarged to manage heat rejection or its ability to reject heat should be enhanced. In this study, a novel low pressure drizzling-aided spray cooling system (SCR-DS) is proposed for the first time. The thermal performance results were compared with those of a high-pressure nozzle-aided spray system (SCR-NS) and a conventional SCR system (SCR-CS). Based on the results, the coolant entry temperature to the stack reduced by up to 1.78 °C, and 2.75 °C when SCR-NS and SCR-DS configurations were active, respectively. Among the various operating factors, the spray cooling performance was significantly influenced by air velocity, spray temperature, and spray flow rate. Furthermore, the experienced mean increments in the heat rejection rate were up to 71.7 % and 123.5 % for the SCD-NS and SCR-DS, respectively, compared to SCR-CS. More importantly, these configurations aid in reducing the size of the SCR by 36.2 % and 45.9 %, respectively, under the same overall heat transfer coefficient conditions. Overall, the SCR-DS configuration was more beneficial than the SCR-NS configuration in terms of thermal performance owing to the slow and steady spray on the SCR surface along with more spray coverage, which aided in better liquid convection and film evaporation.

High-temperature oxidation behaviors of Co-free Cr30Fe30Ni30Al5Ti5 dual-phase multi-component alloys with multi-scale nanoprecipitates

In the context of the growing research interest in multi-component alloys (MAs) and their exceptional performance under extreme environments, the high-temperature oxidation resistance and applications of MAs have attracted significant attention in the field of metallic materials. While the cost-effective and mechanical properties of Co-free MAs are of great importance, their oxidation resistance remains insufficiently understood. In this work, we designed multiple heterogeneous structures within a cast dual-phase Cr30Fe30Ni30Al5Ti5 MA by tailoring the Al and Ti ratio, which consists of body-centered-cubic (BCC) grains reinforced by multi-scale nanoprecipitates (i.e., L21, B2, and η phase) and an L12-strengthened face-centered cubic (FCC) skeleton. Isothermal oxidation experiments at 800 °C, 1000 °C, and 1200 °C with varying exposure durations were conducted. The oxidation kinetics at 800 °C and 1000 °C followed a parabolic law, while both low weight increment and oxidation rate confirm remarkable oxidation resistance. At 800 °C, the oxides mainly consist of Cr2O3 and Al2O3, while are dominated by (TiO2 + Cr2O3) and the mixed oxides of Al2O3, TiO2, and Ti2O above 1000 °C. Importantly, the inability to form a continuous Al2O3 oxide scale at higher temperatures led to a deterioration in oxidation resistance. These findings offer valuable insights into underlying mechanisms contributing to oxidation resistance for Co-free MAs.

Prenatal Genome-Wide Sequencing analysis (Exome or Genome) in detecting pathogenic Single Nucleotide Variants in fetal Central Nervous System Anomalies: systematic review and meta-analysis.

Prenatal Exome (pES) or Genome (pGS) Sequencing analysis showed a significant incremental diagnostic yield over karyotype and chromosomal microarray analysis (CMA) in fetal structural anomalies. Optimized indications and detection rates in different fetal anomalies are still under investigation. The aim of this study was to assess the incremental diagnostic yield in prenatally diagnosed Central Nervous System (CNS) anomalies. A systematic review on antenatal CNS anomalies was performed according to PRISMA guidelines, including n = 12 paper, accounting for 428 fetuses. Results were pooled in a meta-analysis fitting a logistic random mixed-effect model. The effect of interest was the incremental diagnostic rate of pES over karyotype/CMA in detecting likely pathogenic/pathogenic Single Nucleotide Variants (SNVs). A further meta-analysis adding the available pGS studies (including diagnostic coding SNVs only) and submeta-analysis on three CNS subcategories were also performed. The pooled incremental diagnostic yield estimate of pES studies was 38% (95% C.I.: [29%;47%]) and 36% (95% C.I.: [28%;45%]) when including diagnostic SNVs of pGS studies. The point estimate of the effect resulted 22% (95% C.I.: [15%;31%]) in apparently isolated anomalies, 33% (95% C.I.: [22%;46%]) in CNS-only related anomalies (≥1) and 46% (95% C.I.: [38%;55%]) in non-isolated anomalies (either ≥ 2 anomalies in CNS, or CNS and extra-CNS). Meta-analysis showed a substantial diagnostic improvement in performing Prenatal Genome-Wide Sequencing analysis (Exome or Genome) over karyotype and CMA in CNS anomalies.

The association between teat shape and bimodal milk ejection in Holstein dairy cows

Our objectives were to investigate the association of teat shape with (1) bimodality (2) incremental milk flow rates (average flow rates during the first 15 s, 15-30 s, 30-60 s, and 60-120 s of milking), and (3) peak milk flow rate in Holstein dairy cows milked 3 times per day. In this prospective cohort study, we analyzed 220,928 milking observations that were collected from 2,520 cows from a single dairy herd over a period of 31 d. Teat shape was visually assessed and classified into 1 of 4 categories as follows: (1) triangular barrel and pointed teat end (TP), (2) square barrel and round teat end (SR), (3) square barrel, round teat end, and flat in the area of the teat orifice (SRF), and (4) square barrel and flat teat end (SF). Individual cow-level milk flow rates were obtained using electronic on-farm milk meters. We considered bimodality to be present if any of the incremental milk flow rates (flow rates during 15-30 s, 30-60 s, or 60-120 s) were lower than any of the previous rates (flow rates during the first 15 s, 15-30 s, or 30-60 s). The frequency distribution of cows with different teat shapes was as follows: TP, 96 (3.8%); SR, 1,751 (69.5%); SRF, 617 (24.5%); and SF, 56 (2.2%). A generalized linear mixed model revealed differences in the odds of bimodality among cows with different teat shapes. Compared with cows in category SR, the odds (95% confidence interval) of bimodality of cows in other categories were as follows: TP, 0.68 (0.48-0.97); SF, 1.96 (1.21-3.19); and SRF, 1.46 (1.23-1.72). General linear mixed models indicated an association between teat shape and all incremental milk flow rates, with higher milk flow rates being present for cows with teat shapes in the SRF and SF categories. The general linear mixed model for the dependent variable peak milk flow rate indicated an association between teat shape and peak milk flow rate. Least squares means and 95% confidence intervals were 5.1 (4.9-5.3) kg/min for TP, 5.8 (5.5-6.1) kg/min for SF, 5.6 (5.5-5.7) for SRF, and 5.3 (5.3-5.4) for SR, respectively. We conclude that in this study cohort, bimodality is more likely to occur in cows with flat teat ends compared with those with a round teat ends. We attribute this relationship to the difference in milking speed across cows with different teat shapes. Teat shape may serve as a useful phenotype to identify cows that are more likely to exhibit bimodality. Because our study population was unique, future studies considering different circumstances such as breed, milking system, and milking routine are needed before results can be extrapolated.

A chaotic selective encryption scheme for H.265/HEVC video with zero bit rate increment

A chaotic selective encryption scheme for H.265/HEVC video with zero bit rate increment

Growth, survival and reproductive traits of chemical induced and tetraploid-derived triploid Hong Kong oysters (Crassostrea hongkongensis)

Chemical induction (inhibition of polar body II release) and crossing between tetraploid and diploid oysters (mating triploids) are 2 distinct and typical methods for obtaining triploids, and systematic comparative analysis on the phenotypic traits of these two triploids is rare. We tracked and compared the growth, survival, reproductive characteristics and ploidy composition of diploids, induced triploids, and mating triploids, and conducted interaction analysis between genotypes and sites. The results showed that the shell height of larvae showed a significant decrease trend of 3 NTD > 3 NCB > 2 N, while the D larval rate and survival rate of 3 NCB were the lowest, which may be related to the long-term effects of CB toxicity. During offshore farming, from the 180th to 700th day, the shell heights of the three groups followed a significantly decreasing order at both sites, namely 3 NTD > 3 NCB > 2 N (except on the 270th day at Beihai site), and the triploid advantage of shell height in 3 NTD was generally higher than that in 3 NCB, with the same trend in the whole weight. Genotypes and sites always had significant effects on shell height, but their interactions were not significant. The incremental survival rates of the 2 triploid groups were higher than that of the diploid at both sites on the 270th and 700th day, while that of the 3 NTD was significantly higher than the 3 NCB only on the 270th day. In addition, both triploids had some individuals fertile and could produce mature gametes, but the proportion was much lower than that of diploids. Triploid gonadal development is characterized by feminization and a high proportion of hermaphroditism. The fertility ratio and gamete production of 3 NTD were higher than that of 3 NCB, but the relatively high fertility of 3 NTD had no significant effect on its growth and survival. Ploidy composition tracking found that the ploidy composition of 2 N and 3 NTD groups was stable, but the ploidy composition of 3 NCB varied over time. These results indicate that 3 NTD has better performance and higher triploid advantages than 3 NCB, making it more suitable for the commercial production and promotion of triploid C. hongkongensis.

Detrimental impacts and QSAR baseline toxicity assessment of Japanese medaka embryos exposed to methylparaben and its halogenated byproducts

Despite the theoretical risk of forming halogenated methylparabens (halo-MePs) during water chlorination in the absence or presence of bromide ions, there remains a lack of in vivo toxicological assessments on vertebrate organisms for halo-MePs. This research addresses these gaps by investigating the lethal (assessed by embryo coagulation) or sub-lethal (assessed by hatching success/heartbeat rate) toxicity and teratogenicity (assessed by deformity rate) of MeP and its mono- and di-halogen derivatives (Cl− or Br−) using Japanese medaka embryos. In assessing selected apical endpoints to discern patterns in physiological or biochemical alterations, heightened toxic impacts were observed for halo-MePs compared to MeP. These include a higher incidence of embryo coagulation (4–36 fold), heartbeat rate decrement (11–36 fold), deformity rate increment (32–223 fold), hatching success decrement (11–59 fold), and an increase in Reactive Oxygen Species (ROS) level (1.2–7.4 fold)/Catalase (CAT) activity (1.7–2.8 fold). Experimentally determined LC50 values are correlated and predicted using a Quantitative Structure Activity Relationship (QSAR) based on the speciation-corrected liposome-water distribution ratio (Dlipw, pH 7.5). The QSAR baseline toxicity aligns well with (sub)lethal toxicity and teratogenicity, as evidenced by toxic ratio (TR) analysis showing TR < 10 for MeP exposure in all cases, while significant specific or reactive toxicity was found for halo-MeP exposure, with TR > 10 observed (excepting three values). Our extensive findings contribute novel insights into the intricate interplay of embryonic toxicity during the early-life-stage of Japanese medaka, with a specific focus on highlighting the potential hazards associated with halo-MePs compared to the parent compound MeP.