Continuous Reduction Research Articles

Energy recovery in automotive systems: A review of regenerative braking, flywheel, thermoelectric, rankin cycle and electric turbo compound

In the backdrop of escalating global vehicle proliferation and the consequent surge in carbon dioxide (CO2) emissions, there is a compelling urgency to innovate energy recovery methods during vehicular operations for heightened energy efficiency and substantial environmental emission reductions. This paper discussed a variety of vehicle technologies to address environmental emissions issues and critically evaluates contemporary energy recovery technologies across three core dimensions: automotive thermal energy conversion, electronic turbine systems (ETC), and kinetic energy recovery systems. By analyzing empirical data encompassing CO2 emission reduction, energy recovery efficiency enhancement, fuel economy improvement, and applicability diversity across vehicle models, the study aims to establish a scientific foundation for continuous vehicular energy efficiency enhancement and emission reduction. This entails a comprehensive investigation of internal combustion engine principles for potential heat energy recovery, juxtaposing conventional and advanced cycles like the Rankine cycle. Moreover, it involves assessing ETC effectiveness in utilizing exhaust energy while acknowledging system complexity and dynamic response challenges. Additionally, the performance disparities of kinetic energy recovery systems like regenerative braking and exhaust energy recovery in distinct operational contexts are examined. By meticulously comparing experimental data, the paper intends to provide a comprehensive assessment of each technologys merits and drawbacks in advancing energy efficiency and emission reduction, try to pick one or more combinations to minimise the impact, thereby guiding future research and application in automotive energy recovery, and contributing to sustainable automotive engineering technology advancement.

Synergistic Effects of Total Ionizing Dose and Single-Event Upset in 130 nm 7T Silicon-on-Insulator Static Random Access Memory

The exposure of spaceborne devices to high-energy charged particles in space results in the occurrence of both a total ionizing dose (TID) and the single-event effect (SEE). These phenomena present significant challenges for the reliable operation of spacecraft and satellites. The rapid advancement of semiconductor fabrication processes and the continuous reduction in device feature size have led to an increase in the significance of the synergistic effects of TID and SEE in static random access memory (SRAM). In order to elucidate the involved physical mechanisms, the synergistic effects of TID and single-event upset (SEU) in a new kind of 130 nm 7T silicon-on-insulator (SOI) SRAM were investigated by means of cobalt-60 gamma-ray and heavy ion irradiation experiments. The findings demonstrate that 7T SOI SRAM is capable of maintaining normal reading and writing functionality when subjected to TID irradiation at a total dose of up to 750 krad(Si). In general, the TID was observed to reduce the SEU cross-section of the 7T SOI SRAM. However, the extent of this reduction was influenced by the heavy ion LET value and the specific writing data pattern employed. Based on the available evidence, it can be proposed that TID preirradiation represents a promising avenue for enhancing the resilience of 7T SOI SRAMs to SEU.

A Protocol to Extract a Specific Genomic Region from a Public Whole-Genome Database and Modify Analytical Bin Length for Population Genetic Studies.

With the advent of "next-generation" sequencing and the continuous reduction in sequencing costs, an increasing amount of genomic data has emerged, such as whole-genome, whole-exome, and targeted sequencing data. These applications are popular not only in mega sequencing projects, such as the 1000 Genomes Project and UK BioBank, but also among individual researchers. Evolutionary genetic analyses, such as the dN/dS ratio and Tajima's D, are demanded more and more for whole-genome-level population data. These analyses are often carried out under a uniform custom bin size across the genome. However, these analyses require subdivision of a genomic region into functional units, such as protein-coding regions, introns, and untranslated regions, and computing these genetic measures for large-scale data remains challenging. In a recent investigation, we successfully devised a method to address this issue. This method requires a multi-sample VCF file containing population data, a reference genome, target regions in the BED file, and a list of samples to be included in the analysis. Given that the targeted regions are extracted in a new VCF file, targeted population genetic analysis can be performed. We conducted Tajima's D analysis using this approach on intact and pseudogenes, as well as non-coding regions.

Long-term safety and effectiveness of lurasidone in adolescents and young adults with schizophrenia: pooled post hoc analyses of two 12-month extension studies

Background and ObjectivesThe aim of this analysis was to evaluate the long-term safety and effectiveness of lurasidone in the treatment of schizophrenia in adolescents and young adults (13–25).MethodsThe 2 pooled studies used similar designs and outcome measures. Patients (13–25) with schizophrenia completed an initial double-blind 6-week trial of lurasidone (40 and 80 mg/day) in the adolescent trial and (80 and 160 mg/day) in the young adult trial. In open-label long-term trials, adolescent patients were treated with 20–80 mg/day lurasidone, and adults were treated with 40–160 mg/day lurasidone. Efficacy was evaluated based on the Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression-Severity Scale (CGI-S).ResultsThe safety population consisted of 306 patients (mean age, 16.2 years; 208 patients (68.0%) who completed 12 months of treatment; 8.2% who discontinued treatment by 12 months due to an adverse event). The mean (SD) changes in the PANSS total score from the extension baseline to months 6 and 12 were − 11.8 (13.9) and – 15.3 (15.0), respectively (OC), and the mean (SD) changes in the CGI-S score were − 0.8 (1.0) and − 1.0 (1.1), respectively (OC). The most frequent adverse events were headache (17.6%), anxiety (11.4%), schizophrenia (9.8%), and nausea (9.8%). No clinically meaningful changes were observed in weight, metabolic parameters, or prolactin.ConclusionsIn adolescents and young adults with schizophrenia, treatment with lurasidone was generally well tolerated and effective. Long-term treatment was associated with a continued reduction in symptoms of schizophrenia. Long-term treatment was associated with minimal effects on weight, metabolic parameters, and prolactin.Clinicaltrials.gov identifiers D1050234, D1050302.

Impacts of artificial intelligence on carbon emissions in China: in terms of artificial intelligence type and regional differences

The influence of artificial intelligence (AI) on carbon emissions has long been contentious, and accurately clarifying this impact is crucial for the realization of sustainable smart cities. This article investigates the impact of AI on carbon emissions, distinguishing between applied and innovative AI types. Analyzing data from 267 Chinese cities between 2008 and 2019, the study reveals that applied AI reduces carbon dioxide emissions by an average of 40,100 tons per unit increase. In contrast, innovative AI initially leads to emissions increases before ultimately decreasing, illustrating an inverted U-shaped relationship. Regional variations in AI's impact on emissions are influenced by each region's developmental focus and stage of AI deployment. Specifically, differences arise due to the continuous carbon reduction (-0.024) associated with applied AI and the initial emission increase (0.129) attributed to innovative AI. The study underscores the significance of tailored regional strategies in AI development for fostering sustainable smart cities. These findings contribute to the ongoing discourse on AI's environmental impact, offering insights to inform targeted approaches in green, sustainable urban planning.

KWH Cost Analysis of Energy Storage Power Station Based on Changing Trend of Battery Cost

Energy storage plays a vital role in enhancing the resilience of the power grid. Utilizing typical capacity and power energy storage application scenarios, coupled with industry research data and technical analysis of energy storage, this study calculates the cost of energy storage per kilowatt-hour and the associated mileage cost. The findings indicate that the current cost per kilowatt-hour of electrochemical energy storage ranges from approximately 0.6 to 0.9 yuan/(kW⋅h), revealing a considerable gap between the target cost for widespread application and the range of 0.3 to 0.4 yuan/(kW⋅h). Therefore, the development of energy storage technologies (EST) should prioritize achieving “low cost, long life, high safety, and easy recycling,” taking into account a comprehensive assessment of system manufacturing, system lifespan, system safety, and recycling. This paper delves into the changing trend of battery costs and their impact on kilowatt-hours, presenting strategic suggestions to reduce the kilowatt-hour cost of ESP stations. The research underscores that a continuous reduction in battery costs will contribute to enhancing the economic benefits of ESP stations and provide robust support for the future development of the energy storage industry.

Associations between device-measured and self-reported physical activity and common mental disorders: Findings from a large-scale prospective cohort study

ObjectivesTo investigate the associations between device-measured and self-reported physical activity (PA) and incident common mental disorders in the general population.Design and settingLarge-scale prospective cohort study.ParticipantsUsing the UK Biobank data, a...

Radiocapitellar joint plasty for missed monteggia fracture with radial head deformity in children: a retrospective study.

The retrospective study reviewed the clinical and radiological outcomes of patients treated with radiocapitellar joint plasty. 10 children with missed Monteggia fracture (MMF) were reviewed. The average time from injury to operation was 20 months. The average age of children who underwent the operation was 10.5 years. 6 flat and 4 domed radial heads were included. 7 type I and 3 type III MMF were identified based on the Bado classification. All children with MMF were treated by open radial head reduction with radiocapitellar joint plasty and ulnar osteotomy (UO). The average union time was 4.9 ± 2.6 months. The average osteotomy angle to reduce the radial head was 15.7 ± 3.5°, and the average lengthening of the ulna was 8.2 ± 3.2 mm. The average preoperative flexion range of motion was 110.5 ± 9.1°, and the postoperative flexion range of motion was 138.8 ± 15.1° (p < 0.05). The average preoperative extension range of motion was 10.1 ± 3.2°, and the postoperative extension range of motion was 5.5 ± 3.3° (p < 0.05). The average preoperative pronation range of motion was 78.8 ± 8.7°, while the postoperative pronation range of motion was 81.1 ± 5.6° (p > 0.05). The average preoperative supination range of motion was 68.3 ± 9.7°, and the postoperative supination range of motion was 80.1 ± 7.8° (p < 0.05). The preoperative Kim score was 66.5 ± 10.9°, and the postoperative Kim score was 88.1 ± 12.6 (p < 0.05). The radial head was completely reduced in 9 patients, and subluxation in 1 patient. Osteoarthritis of the radiocapitellar joint was observed in 2 patients. Radiocapitellar joint plasty is effective surgical intervention for MMF with radial head deformity. It yields favorable functional outcomes while ensuring continued radial head reduction.

Impact of Anthropogenic Activities on Sedimentary Records in the Lingdingyang Estuary of the Pearl River Delta, China

High-intensity anthropogenic activities have greatly altered the estuarine-shelf depositional processes of sediments, and the intensity and frequency of the impacts of human interventions have far exceeded the natural development of estuarine systems. Since the reform and opening up, human activities such as dams, sand mining, channel dredging, and reclamation have already caused anomalous changes in the dynamical–sedimentary–geomorphological processes of the Lingdingyang Estuary (LE). Analyzing the impact of high-intensity anthropogenic activities on sedimentary processes and the hydrodynamic environment through sedimentary records can provide a scientific basis for predicting the evolution of the estuary and the sustainable development of the Guangdong–Hongkong–Macao Greater Bay Area. The aims of this study are to reveal the impact of varying intensity human activities across different periods on depositional pattern and conduct a preliminary investigation into the spatial differences in sedimentary characteristic attributed to human activities. Two cores (LD11 and LD13) located in the LE were selected for continuous scanning of high-resolution XRF, grain size, and 210Pbex dating tests, and scrutinized with the previous studies of the historical process of human activities in the LE. The results show the following: (1) The abrupt alterations in 210Pbex, geochemical indices, and grain size in LD13 happened in close proximity to the 95 cm layer, suggesting a shift in the sedimentary environment during 1994. (2) In the context of the continuous reduction in water and sediment flux into the LE after 1994, the large-scale and high-intensity human activities like sand mining, channel dredging, and reclamation are responsible for the sedimentation rate increase rather than decrease, the coarsening of sediment fractions, the frequent fluctuations in Zr/Rb, Zr/Al, Sr/Fe, and Sr/Al ratios, and the increase in anomalous extremes. (3) Sedimentary records found in locations varying in anthropogenic intensities differ greatly. Compared with the nearshore siltation area, the grain size composition in the channel area is noticeably coarser and exhibits a wider range of grain size variations. The 210Pbex is strongly perturbed and the vertical distribution is disturbed; the phenomenon of multiple inversions from the surface downwards is shown, making it impossible to carry out sedimentation rate and dating analysis, and the geochemical indicators have changed drastically without any obvious pattern. The evidence of the human activities can be retrieved in the sedimentary record of the estuary and provide a different angle to examine the impacts of the human activities.

A reinforcement learning method for two‐layer shipboard real‐time energy management considering battery state estimation

AbstractIncreasing global environmental concerns encourage a continuous reduction in carbon emissions from the shipping industry. It has become an irreversible trend to replace traditional fossil fuels with advanced energy storage technology. However, an improper energy management leads to not only energy waste but also undesired costs and emissions. Accordingly, the authors develop a two‐layer shipboard energy management framework. In the initial stage, a shipboard navigation planning problem is formulated that considers battery state estimation and is subsequently solved using particle swarm optimisation to obtain an optimal speed trajectory. To track the scheduled speed, a reinforcement learning method based on a deep Q‐Network is proposed in the second stage to realise real‐time energy management of the diesel generator and energy storage system. This approach ensures that the state of charge remains within a safe range and that the performance is improved, avoiding excessive discharge from the energy storage systems and further enhancing the efficiency. The numerical results demonstrate the necessity and effectiveness of the proposed method.

An Insight into the Impact of Nano CuCo2O4 Doping on the Optical and Dielectric Performance of PMMA/Carbon Nanoparticles

In the present study, novel functional properties were achieved for polymethyl methacrylate (PMMA) through loading with carbon nanoparticles (CNPs) as well as varying quantities of CuCo2O4 nanoparticles. The blends obtained were subjected to different characterization techniques. Extensive investigations of different optical properties were carried out, covering linear and nonlinear optical properties. After the incorporation of CNPs/CuCo2O4 in the host polymer matrix, the absorbance, reflectance and refractive index exhibited improvements, while continuous reductions in both direct and indirect optical band gap energies were observed. Significant improvements in the linear and nonlinear optical parameters were observed with increasing CuCo2O4 doping levels. Dielectric measurements provided insights into the impact of CuCo2O4 content on the ac conductivity, energy density, dielectric properties, and electric modulus across all blends. The sample doped with 1.5 wt% exhibited the highest dielectric constant. In conclusion, the optical and dielectric properties of the PMMA/CNPs/x wt% CuCo2O4 blends make them promising candidates in optoelectronics and photocatalysis applications.

An Intermittent Fasting Intervention for Black Adults Can Be Feasibly Implemented in Black Churches: A Cluster Randomized Controlled Pilot Study

BackgroundIntensive lifestyle interventions, including modest reductions in daily caloric intake (ie, continuous calorie energy reduction [CER]), are recommended by US national professional health organizations (eg, American Heart Association). However, they are less effective in Black communities. A burgeoning literature has reported the promise of intermittent fasting (IF) as an alternative strategy for weight loss. However, IF studies have been conducted with White participants predominately and provided participant resources not readily available in real-world situations. ObjectiveWeight-loss and weight-related outcomes of a scalable (ie, able to be widely disseminated and implemented) IF intervention developed with and for Black adults were compared with a CER intervention for the purpose of determining IF’s feasibility (ie, initial effectiveness, adherence, and acceptance) in a Black community. DesignA cluster randomized controlled pilot study was conducted. Participants/settingA total of 42 Black adults with a body mass index (calculated as kg / m2) ≥25 were recruited from 5 Black churches (3 IF and 2 CER) in Western New York State from September 2021 to May 2022. Participants were free of medical conditions that might have contraindicated participation in a weight-reduction program and other factors that might affect weight loss. InterventionsCommunity health workers delivered the 6-month, 16-session, faith-based IF and CER interventions. Main outcome measuresThe primary outcome was feasibility, consisting of initial effectiveness on body weight (ie, percent body weight lost from baseline to 6-month follow-up), adherence, and acceptability. Statistical analyses performedDescriptive statistics and linear mixed models accounting for within-church clustering were used. A baseline covariate corresponding to the outcome variable was included in the model. Intent-to-treat analysis was used. ResultsThere was statistically significant weight loss within both arms (IF: –3.5 kg; 95% CI –6 to –0.9 kg, CER: –2.9 kg; 95% CI –5.1 to –0.8 kg) from baseline to 6-month follow-up. Compared with CER, IF led to significantly lower daily energy intake (414.2 kcal; 95% CI 55.2 to 773.2 kcal) and fat intake (16.1 g; 95% CI 2.4 to 29.8 g). IF may result in lower fruit and vegetable intake (–103.2 g; 95% CI –200.9 to –5.5 g) and fiber intake –5.4 g; 95% CI –8.7 to –2 g) compared with CER. Participants in the IF arm completed a mean (SE) of 3.8 (1.4) more self-monitoring booklets compared with those in the CER arm (P = .02). Participants reported high levels of satisfaction with the program. ConclusionsAn IF intervention developed with and for Black adults can be feasibly implemented in Black churches. Larger studies need to be conducted to ascertain the extent IF can serve as a viable weight-loss alternative to CER interventions in Black communities.

Wrinkling of fluid deformable surfaces.

Wrinkling instabilities of thin elastic sheets can be used to generate periodic structures over a wide range of length scales. Viscosity of the thin elastic sheet or its surrounding medium has been shown to be responsible for dynamic processes. We here consider wrinkling of fluid deformable surfaces. In contrast with thin elastic sheets, with in-plane and out-of-plane elasticity, these surfaces are characterized by in-plane viscous flow and out-of-plane elasticity and have been established as model systems for biomembranes and cellular sheets. We use this hydrodynamic theory and numerically explore the formation of wrinkles and their coarsening, either by a continuous reduction of the enclosed volume or bythe continuous increase of the surface area. Both lead to almost identical results for wrinkle formation and the coarsening process, for which a scaling law for the wavenumber is obtained for a broad range of surface viscosity and rate of change of volume or area. However, for large Reynolds numbers and small changes in volume or area, wrinkling can be suppressed and surface hydrodynamics allows for global shape changes following the minimal energy configurations of the Helfrich energy for corresponding reduced volumes.

Degradation of remaining mechanical properties of bainitic 2.25Cr1Mo steel during creep

In this work, the microstructure and remaining mechanical properties of bainitic 2.25Cr1Mo steel plate used in steam generator of sodium cooled fast reactor during creep were systematically examined. Creep tests at 530 °C with a rupture time up to 18800 h reveals that the creep stress correlates linearly with the Larson-Miller parameter (PLM), while the creep plasticity is rather independent on PLM. The remaining strength parameters, such as yield strength (RP0.2), ultimate tensile strength (Rm) and hardness (H), are found to linearly decrease with PLM, while the remaining plasticity is seen to increase. It suggests that the application of creep stress to the steel accelerates the softening of the material. During the creep process, the dislocation density in bainitic matrix decreases, while the number density of carbides increases, sacrificing the solution strengthening and leading to a continual reduction in the lattice parameter. Although abundant fine carbides precipitate after creep rupture, the remaining strength is however reduced. Instead, the weakening effect due to reduction in dislocation and solute content overwhelms the strengthening of precipitation, resulting in a degradation of the remaining strength. The obtained remaining mechanical properties are attempted to be applied in the design and operation assessment of steam generator.

Formal timing analysis of gate-level digital circuits using model checking

Due to the continuous reduction in the transistors sizing ruled by the Moore’s law, digital devices have become smaller, and more complex resulting in an enormous rise in the delay variations. Therefore, there is a dire need of precise and rigorous timing analysis to overcome anomalies during the timing analysis. Timings of digital circuits can be verified using various simulation or static timing analysis (STA) based tools but they provide estimated results due to their inherent in-exhaustive nature or report timing paths corresponding to non-existent functional paths, respectively. Formal verification provides complete and sound analysis results and has widely been used for the functional verification of digital circuits but its application in the timing analysis domain is somewhat limited. We present a generic framework to perform formal timing analysis of digital circuits with the help of Uppaal model-checker. The given digital circuit along with its timing parameters in the form of state transition diagram are modeled using timed automata in the Uppaal model checker. Timing delays are calculated from corresponding technology parameters, and Quartus Prime Pro is used to obtain the information about the circuits’ paths. In order to make the analysis scalable, we also propose a novel path partitioning technique and compare its results with complete path analysis and traditional STA. The formal model is verified with the help of properties to assess the timing characteristics, like time period of a clock, critical path, and propagation delay of the considered circuit. Modeling and verification of ISCAS-85 and ISCAS-89 benchmark circuits is presented for illustration purposes.

Continuous CO2 capture and reduction to CO by circulating transition-metal-free dual-function material in fluidized-bed reactors

To mitigate global warming and achieve a sustainable society, innovative technologies for efficient CO2 utilization are required. Integrated CO2 capture and reduction (CCR) using dual-function materials (DFMs) is favorable owing to its potentially low energy consumption, capital investment, and processing costs. Although numerous studies have focused on catalytic science, continuous and steady-state CCR operations have not been sufficiently addressed from an engineering perspective. In this study, a circulating fluidized bed (CFB) system is investigated for continuous CCR to syngas (CO + H2). In the CFB system, transition-metal-free DFM (Na/Al2O3) particles are circulated between two bubbling fluidized-bed reactors. The DFM captures CO2 in one reactor (CO2 capture reactor) and reduces the captured CO2 to CO by the reaction with H2 in the other reactor (H2 reactor). The effluent gas concentrations from both reactors reach steady state and are maintained for over 8 h. For the product gas from the H2 reactor, the CO2 conversion and CO selectivity exceed 80 % and 99 %, respectively. However, the H2 conversion is <20 %, indicating a potential challenge for the CFB system for integrated CCR. Furthermore, this study confirms that the H2/CO ratio for syngas can be controlled by adjusting the experimental conditions (particularly, the H2 flow rate). Consequently, the CFB system can be modified to facilitate the interaction between H2 gas and the DFM particles.

Growth Characteristics of Ramet System in Phyllostachys praecox Forest under Mulch Management.

The ramet system is a typical structural type in the life history of clonal plants. This massive structure is formed by many similar ramets connected by underground rhizomes, which are independent and mutually influential. Therefore, the ramet system is unique to bamboo forests, and its role in the construction, maintenance, and productivity of bamboo populations is irreplaceable. Mulch management is a high-level cultivation model for bamboo forests that is used to cultivate bamboo shoots. However, the basic conditions of bamboo ramet systems in this managed model are poorly understood. This study analyzed the underground rhizome morphology, bud bank, and branching of bamboo ramets in a Phyllostachys praecox C.D. Chu et C.S. Chao 'Prevernalis' forest to explore the growth patterns of bamboo ramets in high-level management fields. In mulched bamboo forests, the bamboo rhizomes, distributed in intermediate positions of the bamboo ramet system, were long with many lateral buds and branches, and those at the initial and distal ends were short with few lateral buds and branches. The initial end of the ramet system reduced the ramet system, the intermediate part expanded the ramet system, and the distal end promoted ramet system regeneration. Owing to the continuous reduction, expansion, and renewal of ramet systems, the bamboo rhizome system demonstrates mobility and adaptability. This study found that a higher level of bamboo forest management increased the possibility of artificial fragmentation of the ramet system and that improving the efficiency of the ramet system was beneficial for maintaining its high vitality. Thus, this study provides a crucial reference for guiding the precise regulation of bamboo ramet systems in artificial bamboo forests.

Birth-cohort patterns of e-cigarette and other tobacco use among adolescents in the US

BackgroundE-cigarette use has increased considerably among US adolescents. While many studies have described cross-sectional prevalence trends of youth e-cigarette use, less is known about cohort or generational initiation and use patterns. MethodsWe used data from the US National Youth Tobacco Survey (NYTS) from 2014 to 2022 and age-period-cohort models to analyze age-specific patterns of e-cigarette use initiation and prevalence by cohort and calendar. For comparison, we also examined initiation and prevalence for cigarettes, cigars, and smokeless tobacco, using NYTS data from 1999 to 2022. ResultsAge-specific e-cigarette initiation and prevalence varied considerably by calendar year and birth cohort. There was a rapid increase in e-cigarette initiation and prevalence starting with the 1995 birth cohort, peaking with the 2005 birth cohort, and showing signs of decline with more recent cohorts. In contrast, there were substantial continuous reductions in cigarette, cigar, and smokeless use initiation and prevalence by birth cohort. While the reductions in cigarette smoking started with the 1980s birth cohorts, cigar and smokeless initiation and prevalence did not decrease until the 1990–1995 cohorts. ConclusionsDespite their recent emergence, e-cigarette use has varied considerably across US adolescent cohorts. After early increases, e-cigarette use and initiation peaked with the 2005 birth cohort. These patterns are in contrast with the continuous decreases by cohort in cigarette, cigar, and smokeless use and initiation. As the tobacco product landscape continues to evolve, it will be essential to monitor patterns of use of adolescent and young adult cohorts as they age into adulthood.

The jacktree genome and population genomics provides insights for the mechanisms of the germination obstacle and the conservation of endangered ornamental plants.

Sinojackia Hu represents the first woody genus described by Chinese botanists, with all species classified as endangered ornamental plants endemic to China. Their characteristic spindle-shaped fruits confer high ornamental value to the plants, making them favored in gardens and parks. Nevertheless, the fruits likely pose a germination obstacle, contributing to the endangered status of this lineage. Here we report the chromosome-scale genome of S. xylocarpa, and explore the mechanisms underlying its endangered status, as well as its population dynamics throughout evolution. Population genomic analysis has indicated that S. xylocarpa experienced a bottleneck effect following the recent glacial period, leading to a continuous population reduction. Examination of the pericarp composition across six stages of fruit development revealed a consistent increase in the accumulation of lignin and fiber content, responsible for the sturdiness of mature fruits' pericarps. At molecular level, enhanced gene expression in the biosynthesis of lignin, cellulose and hemicellulose was detected in pericarps. Therefore, we conclude that the highly lignified and fibrotic pericarps of S. xylocarpa, which inhibit its seed germination, should be its threatening mechanism, thus proposing corresponding strategies for improved conservation and restoration. This study serves as a seminal contribution to conservation biology, offering valuable insights for the study of other endangered ornamental plants.

Predicting Soil Erosion Using RUSLE and GeoSOS-FLUS Models: A Case Study in Kunming, China

Revealing the relationship between land use changes and soil erosion provides a reference for formulating future land use strategies. This study simulated historical and future soil erosion changes based on the RULSE and GeoSOS-FLUS models and used a random forest model to explain the relative importance of natural and anthropogenic factors on soil erosion. The main conclusions are as follows: (1) From 1990 to 2020, significant changes in land use occurred in Kunming, with a continuous reduction in woodland, grassland, and cropland, being converted into construction land, which grew by 195.18% compared with 1990. (2) During this period, the soil erosion modulus decreased from 133.85 t/(km²·a) in 1990 to 130.32 t/(km²·a) in 2020, with a reduction in soil loss by 74,485.46 t/a, mainly due to the conversion of cropland to construction and ecological lands (woodland, grassland). (3) The expansion of construction land will continue, and it is expected that by 2050, the soil erosion modulus will decrease by 3.77 t/(km²·a), 4.27 t/(km²·a), and 3.27 t/(km²·a) under natural development, rapid development, and ecological protection scenarios, respectively. However, under the cropland protection scenario, the soil erosion modulus increased by 0.26 t/(km²·a) compared with 2020. (4) The spatial pattern of soil erosion is influenced by both natural and anthropogenic factors, and as human activities intensify in the future, the influence of anthropogenic factors will further increase. Traditionally, the expansion of construction land is thought to increase soil loss. Our study may offer a new perspective and provide a reference for future land use planning and soil loss management in Kunming.